KINDAI UNIVERSITY


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KOHAMA Takeshi

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FacultyDepartment of Computational Systems Biology / Graduate School of Biology-Oriented Science and Technology
PositionAssociate Professor
Degree
Commentator Guidehttps://www.kindai.ac.jp/meikan/892-kohama-takeshi.html
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Last Updated :2020/11/25

Education and Career

Academic & Professional Experience

  •   2013 ,  - 2014 , Faculty of Biology-Oriented Science and Technology, Kindai University

Research Activities

Research Areas

  • Manufacturing technology (mechanical, electrical/electronic, chemical engineering), Measurement engineering
  • Informatics, Intelligent informatics
  • Life sciences, Biomaterials
  • Life sciences, Biomedical engineering
  • Informatics, Intelligent robotics
  • Informatics, Perceptual information processing
  • Humanities & social sciences, Educational technology
  • Life sciences, Biophysics
  • Life sciences, Neuroscience - general
  • Life sciences, Neuroscience - general
  • Informatics, Biological, health, and medical informatics
  • Humanities & social sciences, Cognitive sciences
  • Informatics, Intelligent robotics
  • Informatics, Perceptual information processing

Published Papers

  • Evaluating activities of daily living using an infrared depth sensor: KINECTTM., Kusunoki M, Kohama T, Yamada Y, Fujita E, Okada S, Maeda A, Takeshima N, Disability and rehabilitation. Assistive technology, Disability and rehabilitation. Assistive technology, 1 - 11, Mar. 2018 , Refereed
  • Analysis of interactions between lecturers and students., Eiji Watanabe, Takashi Ozeki, Takeshi Kohama, Proceedings of the 8th International Conference on Learning Analytics and Knowledge, LAK 2018, Sydney, NSW, Australia, March 07-09, 2018, Proceedings of the 8th International Conference on Learning Analytics and Knowledge, LAK 2018, Sydney, NSW, Australia, March 07-09, 2018, 370 - 374, 2018 , Refereed
  • Quantitative comparison of cognitive load derived from voice or manual responses based on microsaccade rate analyses, Takeshi Kohama, Yuma Nakai, Shohei Ohtani, Masaya Yamamoto, Shinichi Ueda, Hisashi Yoshida, The Transactions of Human Interface Society, The Transactions of Human Interface Society, 19(2), 189 - 197, May 2017 , Refereed
  • “A microsaccade detection method by using an order-statistic time-window analysis, Shohei Otani, Takeshi Kohama, Sho Kikkawa, Hisashi Yoshida, 18(1), 19 - 25, Dec. 2016 , Refereed
  • 網膜‐外側膝状体間における視覚情報のリマッピング, 久保賢典, 小濱剛, 吉田久, Memoirs of the Faculty of Biology-Oriented Science and Technology of Kinki University, Memoirs of the Faculty of Biology-Oriented Science and Technology of Kinki University, (38), 11‐20, Oct. 31 2016
  • 視覚における注意のしくみとその産業応用 微小な眼球運動の解析に基づく視覚的注意の状態推定, 小濱剛, 光学, 光学, 45(1), 9‐15, Jan. 10 2016
  • Estimation of Attentional State Based on Analyses of Fixation Eye Movements, 小濱 剛, 光学 = Japanese journal of optics : publication of the Optical Society of Japan, 光学 = Japanese journal of optics : publication of the Optical Society of Japan, 45(1), 9 - 15, Jan. 2016
  • Which is better Median Filter or Linear Filter as a Smoother?, KIKKAWA Sho, KOHAMA Takeshi, YOSHIDA Hisashi, Mem Fac Biol Oriented Sci Technol Kinki Univ, Mem Fac Biol Oriented Sci Technol Kinki Univ, (36), 9 - 17, Sep. 2015 , Refereed
  • e‐Learningにおける受講者によるノーティング動作の分析, WATANABE EIJI, OZEKI TAKASHI, KOHAMA TAKESHI, 電子情報通信学会論文誌 D(Web), 電子情報通信学会論文誌 D(Web), J97-D(12), 1725-1728 (WEB ONLY), Dec. 01 2014
  • 網膜神経系数理モデルを対象にした大規模シミュレーションの並列計算手法, NISHINO MAKOTO, KOHAMA TAKESHI, YOSHIDA HISASHI, Mem Fac Biol Oriented Sci Technol Kinki Univ, Mem Fac Biol Oriented Sci Technol Kinki Univ, (34), 35 - 46, Sep. 30 2014
  • Analysis and extraction of behaviors by students in lectures., Eiji Watanabe, Takashi Ozeki, Takeshi Kohama, Proceedings of the 7th International Conference on Educational Data Mining, EDM 2014, London, UK, July 4-7, 2014, Proceedings of the 7th International Conference on Educational Data Mining, EDM 2014, London, UK, July 4-7, 2014, 329 - 330, 2014 , Refereed
  • Analysis of Behaviors by Audience in Lectures by Using Time-series Models., Eiji Watanabe, Takashi Ozeki, Takeshi Kohama, CSEDU 2014 - Proceedings of the 6th International Conference on Computer Supported Education, Volume 1, Barcelona, Spain, 1-3 April, 2014, CSEDU 2014 - Proceedings of the 6th International Conference on Computer Supported Education, Volume 1, Barcelona, Spain, 1-3 April, 2014, 191 - 196, 2014 , Refereed
  • An objective assessment of stimulus-independent thoughts by analyzing near-infrared spectroscopy (NIRS) signals of lateral prefrontal cortex activity, 小濱 剛, 吉田 久, 山脇 伸行, 濱野 友紀, 清水 達央, Memoirs of the Faculty of Biology-Oriented Science and Technology of Kinki University = 近畿大学生物理工学部紀要, Memoirs of the Faculty of Biology-Oriented Science and Technology of Kinki University = 近畿大学生物理工学部紀要, 32(32), 7 - 16, Sep. 30 2013 , Refereed
    Summary:[要旨] 従事すべき作業とは関係の無い考え事に注意が奪われている状態では, 覚醒水準とは無関係に判断や応答といった認知パフォーマンスが低下するため, 判断ミスなどのヒューマンエラーによる事故をもたらす危険性が高くなるが, 作業者がそうした状態に陥っていることを客観的に評価することは極めて困難である. 本研究では, 課題とは無関係な考え事をしている状態を課題非依存性思考状態と定義し, このような課題非依存性思考状態が, 認知パフォーマンスに与える影響の客観的な評価を目的として, あらかじめ提示された8桁の数字の記憶を維持しつつ, 同時に課せられた視覚探索課題を遂行する際の, 目標探索時間や前頭前野外側部の近赤外線スペクトロスコピー(Near-Infrared Spectroscopy: NIRS)信号を解析した. 実験の結果, 複数の視覚属性の組み合わせにより定義された視対象の中から唯一の特徴を持った目標を探索する場合においてのみ, 課題非依存性思考の有無により目標探索時間が影響されることが示された.また, この条件においてはNIRS信号から推定された前頭前野外側部の賦活度が高まることも示唆された.これらのことから, 課題非依存性思考によって前頭前野の情報処理リソースが消費されることが示唆され, こうした状況下では, 認知タスクのパフォーマンスが影響を受ける可能性が示された. [Abstract] Working with stimulus-independent thoughts(SITs) often causes the decline of cognitive performances, such as judgments of signals or response times to certain tasks. It might lead to fatal accidents called "human errors" independently of arousal level. The detection and prediction of these errors is extremely difficult, and the measurement technology of inattentiveness has not yet been established. In this study, we investigate the effect of SITs on the performance of visual search tasks. SITs are the streams of thoughts that are unrelated to immediate situations. The subjects memorized the numeral of eight digits as an SIT while carrying out visual search tasks. The reaction time and the near-infrared spectroscopy signals from the lateral prefrontal cortex(PFC) were analyzed to evaluate the effect of SITs objectively. As a result, the average reaction time for searching targets from distracters only in terms of their feature conjunctions increased when having SITs during the tasks. Also, the SITs in these tasks enhance the activity of the lateral PFC. These results suggest that the SITs occupy the resource of attention and it might affect the performances of certain cognitive tasks under these conditions.【注記】本研究は, 近畿大学生物理工学部戦略的研究NO.11-Ⅰ-3 2012, および, JSPS科研費24560534の助成を受けた.
  • Extraction of relationships between page transition and understanding for contents, Proceedings of IEEE International Conference on TALE 2013, Proceedings of IEEE International Conference on TALE 2013, 18 - 23, Aug. 2013 , Refereed
  • A quantitative evaluation of visual factors of cybersickness by analyzing fixation eye movements and heart rate variability, Memoirs of the Faculty of Biology-Oriented Science and Technology of Kinki University, Memoirs of the Faculty of Biology-Oriented Science and Technology of Kinki University, 30, 1 - 16, Sep. 2012 , Refereed
  • Inhibition of microsaccade rate caused by focus of visual attention, Memoirs of the Faculty of Biology-Oriented Science and Technology of Kinki University, Memoirs of the Faculty of Biology-Oriented Science and Technology of Kinki University, 29, 7 - 15, Mar. 2012
  • Visual search model considering spatial modification of visual attributes and cortical magnification of retinal images., Memoirs of the Faculty of Biology-Oriented Science and Technology of Kinki University, Memoirs of the Faculty of Biology-Oriented Science and Technology of Kinki University, 28, 41 - 52, Oct. 2011 , Refereed
  • “A Binocular Vision Model for Solving Autostereograms”, Takeshi Kohama, Yoshihiro Hirata, Journal of the Institute of Image Electronics Engineers of Japan, Journal of the Institute of Image Electronics Engineers of Japan, 40(5), 801 - 807, 2011
    Summary:This study proposes a binocular vision model that reconstructs 3D structures from autostereograms. Our model is a modified version of the model by Hayashi et al., which cannot resolve the autostereograms, and serves to introduce fusion processes by vergence eye movements in order to obtain depth information from autostereograms. Since autostereograms have a periodic plane as the background, our model starts with the vergence motion of two windows corresponding to the left and right eyes to search maximal output of the binocular energy unit that produces autocorrelation-like patterns of the background. Once the optimum vergence angle has been determined, the model calculates paired or unpaired points using the same procedure employed in the model by Hayashi et al. The results indicate that the model can reconstruct 3D structures even from autostereograms, suggesting that the disparity detection system coordinates with the eye movement system to accurately derive depth perception. © 2011, The Institute of Image Electronics Engineers of Japan. All rights reserved.
  • A statistical analysis of attentional effects on drift eye movements, Takeshi Kohama, Haruka Takenaka, Hisashi Yoshida, Naohiro Toda, Kyokai Joho Imeji Zasshi/Journal of the Institute of Image Information and Television Engineers, Kyokai Joho Imeji Zasshi/Journal of the Institute of Image Information and Television Engineers, 64(12), 1892 - 1898, Dec. 2010
    Summary:Recent studies have demonstrated a close relationship between the frequency of microsaccades and covert attention shift. However, there are no arguments of attentional effect on drift movements during attentive or inattentive fixation. We examined whether visual attention has any influence on drift eye movements using statistical analysis of a time series of fixation eye movements. The results indicated that the power in the 3-4 Hz frequency range was enhanced when visual attention was dispersed over the parafoveal visual field. Furthermore, the amplitudes of the drift eye movements were reinforced immediately after the microsaccades, especially after square-wave jerks. These results suggest that microsaccades and drift eye movements are both controlled by higher order brain functions to acquire detailed visual information from the peripheral vision.
  • Predicting human gaze shifts considering the inhibition of return using a modified saliency map model, Memoirs of The Faculty of B.O.S.T. of Kinki University, Memoirs of The Faculty of B.O.S.T. of Kinki University, 24, 45 - 55, Nov. 2009
  • A verification of enhancement of visual perception caused by miniature eye movements based on a model of neural processing of retina, (22), 61 - 69, Sep. 2008
  • Attentional effects on the microsaccadic eye movements, Takeshi Kohama, Shiro Usui, Current Psychology of Cognition, Current Psychology of Cognition, 21(4-5), 377 - 395, May 2002 , Refereed
  • Quantitatively measuring visual attention by analyzing microsaccades, Takeshi Kohama, Ken Shinkai, Shiro Usui, Kyokai Joho Imeji Zasshi/Journal of the Institute of Image Information and Television Engineers, Kyokai Joho Imeji Zasshi/Journal of the Institute of Image Information and Television Engineers, 52(4), 571 - 576, 1998
    Summary:To evaluate the effects of visual attention (VA) on human involuntary miniature eye movements (MEM), we analyzed the microsaccades (MSC), which are components of MEM, under the following three experimental conditions: 1) VA was focused on the foveal object, 2) VA was dispersed in the parafoveal visual field, and 3) VA was focused on one of the parafoveal objects. The results showed that the VA was not focused on the foveal object, the frequency and amplitude of the MSC increased, and the scatter of fixation widened. The results from 2) and 3) showed that the frequency of the MSC was grater in 2) and the mean amplitude of the MSC was similar for both conditions. When VA is not focused, the MSC occur more frequently, and when VA is focused on the foveal object, the amplitude of the MSC reduces. These results suggest that MEM are influenced by VA, and MSC may be used as an indicator of the attentional state. It will be possible to establish whether VA is focused or not on the basis of the analysis of MEM characteristics.
  • An analysis of saccades during Kanji-recognition tasks, Takeshi Kohama, Ken Shinkai, Tsuyoshi Saitoh, Mitsuho Yamada, Shiro Usui, Tatsuo Yoshida, Kyokai Joho Imeji Zasshi/Journal of the Institute of Image Information and Television Engineers, Kyokai Joho Imeji Zasshi/Journal of the Institute of Image Information and Television Engineers, 51(8), 1308 - 1318, 1997
    Summary:In order to consider the effects of spatial attention on human saccadic eye movements, we analyzed peak velocity, duration, latency and amplitude of saccades during Kanji-recognition tasks. The results suggest that the choice of region allocated for spatial attention has no effect on the characteristics of saccades. The distributions of saccadic latency showed 1 to 3 peaks, and their peak values were consistent with the results of earlier studies. Because of these facts, we consider that there are basic phases for making saccades regardless of the complexity of the tasks. The relation between saccadic latency and amplitude shows that a longer latency leads to a smaller amplitude. This suggests that the state of spatial attention before execution of a saccade affects its amplitude. Based on these results, a schematic model of the brain system for generating of saccades is proposed, and the process of generating saccades is hypothesized using this conceptual model.
  • Analysis of fixation points and spatial attention in the process of visual information integration across a saccade, Takeshi Kohama, Tsuyoshi Saitoh, Ken Shinkai, Mitsuho Yamada, Shiro Usui, Tatsuo Yoshida, Terebijon Gakkaishi (Journal of the Institute of Television Engineers of Japan), Terebijon Gakkaishi (Journal of the Institute of Television Engineers of Japan), 50(11), 1781 - 1789, 1996
    Summary:This study examines a contribution of the visual system to the acquisition of visual information during saccadic eye movements (saccade). In the experiment, when the observer made a saccade, the location of a Kanji character displayed on a CRT screen was transferred a random distance and direction, or was kept at the original position. When the character was transferred to a new position, the recognition rate of the character decreased proportionally to the increase in distance between the fixation point after the saccade and the center of the character, in comparison with the case when the character was kept at the original position. We attempted to control the spatial attention during the same tasks. The result suggests that the spatial attention before a saccade might also be involved in the process of visual information acquisition during saccades and the visual system may integrate the positional information into the visual feature information.
  • Analysis of the Relationship between the Information Acquired by the Visual System and the Location of the Fixation Points., J79(1), 101 - 110, Jan. 1996
  • Development of Objective ADL Assessment Particularly in Frail Older Adults Using a Kinect Sensor, Nobuo Takeshima, Takeshi Kohama, Masanobu Kusunoki, Takashi Ogayu, Soichi Okada, Eiji Fujita, Mohammod M. Islam, William F. Brechue, JOURNAL OF AGING AND PHYSICAL ACTIVITY, JOURNAL OF AGING AND PHYSICAL ACTIVITY, 24, S41 - S41, Jun. 2016 , Refereed
  • Analysis of Non-verbal Behaviors by Students in Cooperative Learning, Eiji Watanabe, Takashi Ozeki, Takeshi Kohama, COLLABORATION TECHNOLOGIES AND SOCIAL COMPUTING, COLLABTECH 2016, COLLABORATION TECHNOLOGIES AND SOCIAL COMPUTING, COLLABTECH 2016, 647, 203 - 211, 2016 , Refereed
    Summary:In this paper, we discuss the relationship between non-verbal behaviors and understandings by students in the cooperative learning. First, we detect non-verbal behaviors by students by using image processing methods. Next, we propose a modeling method for non-verbal behaviors. Furthermore, we discuss the relationship between non-verbal behaviors and understandings by students based on the above models.
  • Relationships between behaviors by applicants and interviewer in interview, Eiji Watanabe, Takashi Ozeki, Takeshi Kohama, Proceedings of 2014 International Conference on Interactive Collaborative Learning, ICL 2014, Proceedings of 2014 International Conference on Interactive Collaborative Learning, ICL 2014, 138 - 143, Jan. 21 2015
    Summary:In interviews, the evaluation by the interviewer is affected by not only the reply but also behaviors (eye and face movements) by applicants. Moreover, the evaluation by the interviewer is communicated with applicant as the behavior by the interviewer. Therefore, the interaction between the behaviors by the interviewer and the applicant occurs. In this paper, we show that the evaluation by the interviewer is strongly influenced by behaviors by applicants and the relationship between the evaluation by the interviewer and the behaviors by applicants.
  • A saliency based motion detection model of visual system considering visual adaptation properties, Mitsuhiro Kodama, Takeshi Kohama, Hisashi Yoshida, 2015 37TH ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY (EMBC), 2015 37TH ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY (EMBC), 2015, 6658 - 6661, 2015 , Refereed
    Summary:The purpose of this study is to construct a mathematical model which predicts saliency regions in high-speed egocentric-motion movies, filmed by an embedded camera in a driving vehicle, by reproducing the characteristics of the area MT and MST neurons' receptive fields with consideration of visual adaptation properties. The area MT neurons integrate from the area V1 activation and respond well to regions where higher motion contrasts exist. While the area MST neurons detect global motions such as expansion, contraction, rotation, and so on. We modeled the area MT neurons' receptive fields as a center-surround spatial summation of counter sided motion vectors of visual scenery. The area MST neurons in our model integrate the responses of the MT neurons by convolving with spacial weight functions of which central portions are biased to preferred direction. Visual adaptations were taken as the primary delay filters for each visual feature channel to deplete the saliency of stationary objects and regions during particular frames. The simulation results for the movies which were taken in a running vehicle indicate that the proposed model detects more salient objects around the vanishing point than the conventional saliency based model. To evaluate the performance of proposed model, we defined the moving-NSS (normalized scan-path salience) scores as the averaged NSS scores in each moving time window. The moving-NSS scores for motion images of our model were higher than those of the conventional model.
  • Relationships between behaviors by applicants and interviewer in interview, Eiji Watanabe, Takashi Ozeki, Takeshi Kohama, 2014 INTERNATIONAL CONFERENCE ON INTERACTIVE COLLABORATIVE LEARNING (ICL), 2014 INTERNATIONAL CONFERENCE ON INTERACTIVE COLLABORATIVE LEARNING (ICL), 138 - 143, 2014 , Refereed
    Summary:In interviews, the evaluation by the interviewer is affected by not only the reply but also behaviors (eye and face movements) by applicants. Moreover, the evaluation by the interviewer is communicated with applicant as the behavior by the interviewer. Therefore, the interaction between the behaviors by the interviewer and the applicant occurs. In this paper, we show that the evaluation by the interviewer is strongly influenced by behaviors by applicants and the relationship between the evaluation by the interviewer and the behaviors by applicants.
  • Quantitative assessments of arousal by analyzing microsaccade rates and pupil fluctuations prior to slow eye movements, Shogo Honda, Takeshi Kohama, Tatsuro Tanaka, Hisashi Yoshida, 2014 36TH ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY (EMBC), 2014 36TH ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY (EMBC), 2014, 2229 - 2232, 2014 , Refereed
    Summary:It is well known that a decline of arousal level causes of poor performance of movements or judgments. Our previous study indicates that microsaccade (MS) rates and pupil fluctuations change before slow eye movements (SEMs) (Honda et al. 2013). However, SEM detection of this study was obscure and insufficient. In this study, we propose a new SEM detection method and analyze MS rates and pupil fluctuations while subjects maintain their gaze on a target. We modified Shin et al.'s method, which is optimized for EOG (electrooculography) signals, to extract the period of sustaining SEMs using a general eye tracker. After SEM detection, we analyzed MS rates and pupil fluctuations prior to the initiation of SEMs. As a result, we were able to detect SEMs more precisely than in our previous study. Moreover, the results of eye movements and pupil fluctuations analyses show that gradual rise of MS rate and longitudinal miosis are observed prior to the initiation of SEMs, which is consistent with our previous study. These findings suggest that monitoring eye movements and pupil fluctuations may evaluate the arousal level more precisely. Further, we found that these tendencies become more significant when they are restricted to the initial SEMs.
  • Quantitative evaluation of arousal level based on the analyses of microsaccade rates and pupil fluctuations, Shogo Honda, Takeshi Kohama, Tatsuro Tanaka, Hisashi Yoshida, 2013 35TH ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY (EMBC), 2013 35TH ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY (EMBC), 2013, 2108 - 2111, 2013 , Refereed
    Summary:In this study, we proposed an objective estimation of decline of arousal level by analyzing microsaccade rate and pupil fluctuation while subjects were continuously gazing a fixation target. Previous studies show that the slow eye movements (SEMs) could be a candidate for an indicator of decline of arousal. However, it is not sufficient to evaluate transition of arousal states since SEMs appear just prior to sleep onset. To establish more objective assessment of arousal, we examined the effects of the transition of arousal on microsaccade rate and pupil fluctuation. The subjects were instructed to indicate by mouse clicks when they were aware of having slept. We have analyzed the eye movement and pupil fluctuation data in advance of the occurrence of SEMs which were detected just before the mouse clicks. In the results, longitudinal pupil diameter shrinking and gradual rise of microsaccade rate were observed prior to SEMs. These results suggest that the arousal level could be evaluated by monitoring eye movements and pupil fluctuations.
  • Extraction of relationships between page transition and understanding for contents, Eiji Watanabe, Takashi Ozeki, Takeshi Kohama, Proceedings of 2013 IEEE International Conference on Teaching, Assessment and Learning for Engineering, TALE 2013, Proceedings of 2013 IEEE International Conference on Teaching, Assessment and Learning for Engineering, TALE 2013, 18 - 23, 2013
    Summary:In this paper, we consider a learning environment, which students solve the problem while reading digital contents. Here, we extract the relationship between the frequency for reading each page and the understanding for given problems. The above relationship can be modeled by using neural networks. Furthermore, we use a learning method with forgetting for neural networks for the purpose of clarification of internal representations. Finally, we have analyzed the relationship between the frequency for each page and the understanding for given contents based on the internal representations of multi-layered neural networks. © 2013 IEEE.
  • Attentional effects on gaze preference for salient loci in traffic scenes, Hiroyuki Sakai, Duk Shin, Takeshi Kohama, Yuji Uchiyama, ERGONOMICS, ERGONOMICS, 55(7), 743 - 751, 2012 , Refereed
    Summary:Alerting drivers for self-regulation of attention might decrease crash risks attributable to absent-minded driving. However, no reliable method exists for monitoring driver attention. Therefore, we examined attentional effects on gaze preference for salient loci (GPS) in traffic scenes. In an active viewing (AV) condition requiring endogenous attention for traffic scene comprehension, participants identified appropriate speeds for driving in presented traffic scene images. In a passive viewing (PV) condition requiring no endogenous attention, participants passively viewed traffic scene images. GPS was quantified by the mean saliency value averaged across fixation locations. Results show that GPS was less during AV than during PV. Additionally, gaze dwell time on signboards was shorter for AV than for PV. These results suggest that, in the absence of endogenous attention for traffic scene comprehension, gaze tends to concentrate on irrelevant salient loci in a traffic environment. Therefore, increased GPS can indicate absent-minded driving. Practitioner Summary: The present study demonstrated that, without endogenous attention for traffic scene comprehension, gaze tends to concentrate on irrelevant salient loci in a traffic environment. This result suggests that increased gaze preference for salient loci indicates absent-minded driving, which is otherwise difficult to detect.
  • Analysis of behaviors by lecturer and students in lectures based on piecewise auto-regressive modeling, Eiji Watanabe, Takashi Ozeki, Takeshi Kohama, Proceedings - 2011 IEEE 7th International Conference on Intelligent Computer Communication and Processing, ICCP 2011, Proceedings - 2011 IEEE 7th International Conference on Intelligent Computer Communication and Processing, ICCP 2011, 385 - 390, 2011 , Refereed
    Summary:In this paper, we discuss the analysis of behaviors by lecturer and students in lectures. In lectures, the relationships between lecturer and students depend on not only contents but also the loudness of speech and gestures by lecturer. The behaviors consisting of head and eye movements by students can often represent how they have the interest with the lecture. First, we extract the loudness of speech and the face direction as behaviors by lecturer and the face direction as behaviors by students. Next, we construct piecewise auto-regressive (AR) models for their behaviors. Here, the piecewise AR models can be constructed based on the residual error. Finally, we show the analysis results for a real lecture based on the piecewise AR modeling. © 2011 IEEE.
  • Restoration for JPEG and Blurred Images Based on Ensemble Learning Algorithm, Eiji Watanabe, Takashi Ozeki, Takeshi Kohama, Journal of the Institute of Image Electronics Engineers of Japan, Journal of the Institute of Image Electronics Engineers of Japan, 40(1), 42 - 51, 2011
    Summary:This paper proposes a restoration method for JPEG and blurred images based on ensemble learning algorithm. Such as a median filter, various restoration filters for these images have been already proposed and applied in real images. However, when images have edge and non-edge regions, it is difficult for single filter having fixed coefficients to reduce both blocky and mosquito noises adequately. Here, new restoration methods for JPEG and blurred images are proposed by introducing multiple muliti-layered neural networks. Each neural network can be adapted for edge, flat, and texture regions in images by ensemble learning. From experimental results, the proposed method can obtain good restoration accuracy compared with conventional filters. Moreover, we have confirmed that the proposed method could automatically assign restoration tasks to each neural network according to the characteristics of each region in given distorted images. © 2011, The Institute of Image Electronics Engineers of Japan. All rights reserved.
  • EXTRACTION OF RELATIONS BETWEEN LECTURER AND STUDENTS BY USING MULTI-LAYERED NEURAL NETWORKS, Eiji Watanabe, Takashi Ozeki, Takeshi Kohama, IMAGAPP & IVAPP 2011: PROCEEDINGS OF THE INTERNATIONAL CONFERENCE ON IMAGING THEORY AND APPLICATIONS AND INTERNATIONAL CONFERENCE ON INFORMATION VISUALIZATION THEORY AND APPLICATIONS, IMAGAPP & IVAPP 2011: PROCEEDINGS OF THE INTERNATIONAL CONFERENCE ON IMAGING THEORY AND APPLICATIONS AND INTERNATIONAL CONFERENCE ON INFORMATION VISUALIZATION THEORY AND APPLICATIONS, 75 - 80, 2011 , Refereed
    Summary:In this paper, we discuss the extraction of relationships between lecturer and students in lectures by using multi-layered neural networks. First, a few features concerning for behaviors by lecturer and students can be extracted based on image processing. Here, we adopt the following features as behaviors by lecturer and students; the loudness of speech by lecturer, face and hand movements by lecturer, face movements by students. Next, the relations among the above features concerning on their behaviors by lecturer and students can be represented by multi-layered neural networks. Next, we use a learning method with forgetting for neural networks for the purpose of extraction of rules. Finally, we have extracted relationships between behaviors by lecturer and students based on the internal representations in multi-layered neural networks for a real lecture.
  • Extraction of relations between behaviors by lecturer and students in lectures, Eiji Watanabe, Takashi Ozeki, Takeshi Kohama, 2011 IEEE International Conference on Automatic Face and Gesture Recognition and Workshops, FG 2011, 2011 IEEE International Conference on Automatic Face and Gesture Recognition and Workshops, FG 2011, 945 - 950, 2011 , Refereed
    Summary:In this paper, we discuss the extraction of relations between lecturer and students in lectures by using multi-layered neural networks. Here, the relations among a few features concerning on the behaviors of the lecturer and students can be represented by multi-layered neural networks with the time-delay. Furthermore, we introduce a structural learning algorithm with forgetting for neural networks for the extraction of rules in the interaction. The above time-series models are analyzed focusing on weights in multi-layered neural networks. Concretely, we analyze which lecturer's behaviors (face and hand movements and loudness of speech) give great influences on behaviors by students (face movements). On the contrary, we analyze which student's behavior (face movement) give great influences on behaviors by lecturer. © 2011 IEEE.

Conference Activities & Talks

  • An evaluation index of fixation scan paths based on the similarity of feature vectors,   2013 12
  • The effects of fixation eye movements on retinal responses for two dimensional spatial frequency patterns,   2013 12
  • An automatic counting algorithm of repetitive exercises captured by general motion sensor and a data management system on the cloud services,   2013 11
  • Evaluation of visual factors of visually induced motion sickness by analyzing fixation eye movements and heart rate variability, 35th European Conference on Visual Perception,   2013 08 , 35th European Conference on Visual Perception
  • Persistent inhibition of microsaccades caused by attentional concentration, 35th European Conference on Visual Perception,   2013 08 , 35th European Conference on Visual Perception
  • 注意集中度の客観的評価 -固視微動解析に基づく注意の統制状態の定量化-,   2013 06
  • A mathematical model for reproducing mean square displacement profile of fixation eye movements, Neuro 2013,   2013 06 , Neuro 2013
  • A saliency map computation for dynamic images based on the receptive field properties of visual area MT,   2012 12
  • A slow eye movement (SEM) detection method for objective evaluations of arousal fluctuations,   2012 12
  • A visual search simulation based on a mathematical model of visual attention system,   2012 11
  • A saliency-based prediction of gaze shifts while driving vehicles, Neuroscience2012 The 35th Annual Meeting of the Japan Neuroscience Society,   2012 09 , Neuroscience2012 The 35th Annual Meeting of the Japan Neuroscience Society
  • A simulation study of retinal enhancement effects caused by fixation eye movements, 35th European Conference on Visual Perception,   2012 09 , 35th European Conference on Visual Perception
  • Analysis of reading and writing behaviors for digital contents, IEEE International Conference onTeaching, Assessment and Learning for Engineering 2012,   2012 08 , IEEE International Conference onTeaching, Assessment and Learning for Engineering 2012
  • A simulation analysis of visual enhancement caused by fixation eye movements on retinal responses,   2012 05
  • Microsaccade detection based on a discrete pulse transform analysis,   2012 05
    Summary:This study proposes a method for detecting microsaccades based on a discrete ulse transform analysis (DPT). The general methods for microsaccade detection need to decide the threshold for a differentiation signal of eye movements after enoising by the median filter. The median filter well maintain sharp edges configured by microsaccades, however, theoretical prediction of the behavior is difficult.Because of this unpredictability, the trial and error process is necessitated to decide the threshold value or the order of the filters. The proposed method is to detect microsaccades based on the features of the pulse series produced by DPT. The eye movement signal is divided into smoothed and detail components by multiple orders of LULU filters, then the pulse series which represents the dynamics of movements is calculated. The results show the detected microsaccades is more precise than general method. Furthermore,the start- and end-point of each microsaccades is clearly discriminated.
  • Analysis of reading and writing behaviors for digital contents, IEEE International Conference onTeaching, Assessment and Learning for Engineering 2012,   2012 , IEEE International Conference onTeaching, Assessment and Learning for Engineering 2012
  • Embedding time tag in handwritten memorandum by using sunglasses type camera, The 2012 International Workshop on Advanced Image Technology (IWAIT 2012),   2012 01 , The 2012 International Workshop on Advanced Image Technology (IWAIT 2012)
  • Analysis of reading behaviors by learners for contents on papers and digital devices, 2011 TERA International Conference on Education,   2011 12 , 2011 TERA International Conference on Education
  • A simulation analysis of the effects of miniature eye movements on retinal responses.,   2011 12
  • Microsaccade detection with a order-statistic low-pass differentiation filter.,   2011 12
  • Inhibition of microsaccade rate caused by increase in visual attention, Neuroscience2011 The 34th Annual Meeting of the Japan Neuroscience Society,   2011 09 , Neuroscience2011 The 34th Annual Meeting of the Japan Neuroscience Society
  • Visual search model considering spatial modication of visual attributes, Neuroscience2011 The 34th Annual Meeting of the Japan Neuroscience Society,   2011 09 , Neuroscience2011 The 34th Annual Meeting of the Japan Neuroscience Society
  • Mathematical model of the visual attention system in the posterior parietal and prefrontal lobes, 34th European Conference on Visual Perception,   2011 09 , 34th European Conference on Visual Perception
  • Analysis of behaviors by lecturer and students in lectures based on piecewise auto-regressive modeling, 2011 IEEE International Conference on Intelligent Computer Communication and Processing (ICCP2011),   2011 08 , 2011 IEEE International Conference on Intelligent Computer Communication and Processing (ICCP2011)
  • サングラス型カメラによる手書きメモに関する検討,   2011 08
  • A mathematical model of the saccadic eye movement system,   2011 05
  • Evaluation of arousal level by microsaccade rate and pupil fluctuation,   2011 04
  • Extraction of relations between lecturer and students by using multi-layered neural networks,   2011 03 , Institute for Systems and Technologies of Information, Control and Communication
  • Analysis of global gaze regions of learners detected by sunglasses camera in e-Learning,   2011 01
  • A visual search simulation by using a top-down feature feedback model, Neuro2010,   2010 09 , Neuro2010
  • Measurement of stress and gaze points in tasks of detection of differences between closely similar images and sentences, 33rd European Conference on Visual Perception,   2010 08 , 33rd European Conference on Visual Perception
  • A binocular vision model considering vergence eye movements for solving autostereograms, 33rd European Conference on Visual Perception,   2010 08 , 33rd European Conference on Visual Perception
  • Effects of motion sickness on fixation eye movements,   2010 06
  • Microsaccade rate varies with arousal level,   2010 06
  • A saliency map model with the inhibition of return feedbacks,   2010 05
  • A Statistical Model Analysis of Attentional Effects on Fixational Drift Eye Movements, International Workshop on Image Media Quality and Its Applications (IMQA2010),   2010 05 , International Workshop on Image Media Quality and Its Applications (IMQA2010)
  • A restoration method for JPEG images based on ensemble learning algorithm, Image Electronics and Visual Computing Workshop,   2010 03 , Image Electronics and Visual Computing Workshop
  • Analysis of eye movements of learners in e-learning, International Workshop on Advanced Image Technology 2010,   2010 01 , International Workshop on Advanced Image Technology 2010
  • Analysis of movements of students in e-Learning -Relations between eyes movements and understanding-,   2009 12
  • Analysis of Movements of Students in e-Learning -Relations among face movements, page changes, and understanding-,   2009 12
  • Stimulus-independent thoughts affect visual search task performances,   2009 09 , Elsevier
  • A neural model of discharge profiles in the midbrain to reproduce express saccades, Neuroscience 2009, The 32nd Annual Meeting of the Japan Neuroscience Society,   2009 09 , Neuroscience 2009, The 32nd Annual Meeting of the Japan Neuroscience Society
  • An ambiguous distracter disrupts the recognition of nonverbal graphic symbols, Neuroscience 2009, The 32nd Annual Meeting of the Japan Neuroscience Society,   2009 09 , Neuroscience 2009, The 32nd Annual Meeting of the Japan Neuroscience Society
  • A gaze prediction model considering the inhibition of return based on the saliency map theory, Neuroscience 2009, The 32nd Annual Meeting of the Japan Neuroscience Society,   2009 09 , Neuroscience 2009, The 32nd Annual Meeting of the Japan Neuroscience Society
  • Attentional effects on drift eye movements before and after microsaccades, 32nd European Conference on Visual Perception,   2009 08 , 32nd European Conference on Visual Perception
  • A neural model of discharge profiles in the mid brain to reproduce express saccades,   2009 07
  • A gaze prediction model considering of inhibition of return based on the saliency map theory,   2009 07
  • An ambiguous distractor disrupts higher order cognitive processes,   2009 04
  • An objective estimation for task independent thought on visual search tasks,   2009 04
  • Attentional effects on power spectra for drift eye movements, The European Conference on Visual Perception 2008,   2008 08 , The European Conference on Visual Perception 2008
  • Evaluation of concentration level of visual attention based on quantitative analysis on fixational eye movements,   2008 05
  • Evaluation of concentration level of visual attention based on statistical analysis on drift eye movements,   2008 05
  • Concentration of visual attention inhibits the generation of microsaccades,   2008 05
  • Attentional effect on small drift eye movements during fixation,   2007 12
  • A mathematical model of saccadic eye movement system based on neuronal activity in superior colliculus and basal ganglia,   2007 12
  • A model of small involuntary eye movements to reproduce square-wave jerks, Neuro2007,   2007 09 , Neuro2007
  • A mathmatical model of square-wave jerks during fixation,   2006 09
  • A model of square-wave jerks during eye fixation in human, The fourth asian conference on vision (ACV2006),   2006 07 , The fourth asian conference on vision (ACV2006)
  • A simulation study of intrasaccadic perception based on an early visual system model,   2004 08
  • Visual information and eye movements,   2003 11
  • Attentional effects on the microsaccadic eye movements, 3rd Conference on sensorimotor controls in men and machines,   2001 10 , 3rd Conference on sensorimotor controls in men and machines
  • Does attention affect the fixational stability?, 26th SEIRIKEN International Symposium,   2000 10 , 26th SEIRIKEN International Symposium

Misc

  • Analysis of interactions between lecturer and students in lectures(Second report), 渡邊 栄治, 尾関 孝史, 小濱 剛, 浜野 裕希, 吉田 賢史, 電子情報通信学会技術研究報告 = IEICE technical report : 信学技報, 117, 509, 35, 40,   2018 03 13 , http://ci.nii.ac.jp/naid/40021522569
  • 片眼弱視症例における両眼視,単眼視での左右の固視微動の比較, 白井久美, 小久保奈津, 大谷尚平, 小濱剛, 雑賀司珠也, 日本眼科学会雑誌, 122, 臨増, 208, 208,   2018 03 09 , http://jglobal.jst.go.jp/public/201802242159937731
  • Analysis of interactions between lecturer and students in lectures (Second report), 渡邊栄治, 尾関孝史, 小濱剛, 浜野裕希, 吉田賢史, 電子情報通信学会技術研究報告, 117, 509(HCS2017 93-118), 35‐40,   2018 03 06 , http://jglobal.jst.go.jp/public/201802253631144655
  • Deep Neural Networkを用いた虚弱高齢者の判定, 高木智弘, 小濱剛, 楠正暢, 岡田荘市, 藤田英二, 竹島伸生, 吉田久, 電子情報通信学会大会講演論文集(CD-ROM), 2018, ROMBUNNO.D‐12‐5,   2018 03 06 , http://jglobal.jst.go.jp/public/201802256220139696
  • Analysis of behaviors of audience in presentations(First report), 渡邊 栄治, 尾関 孝史, 小濱 剛, 電子情報通信学会技術研究報告 = IEICE technical report : 信学技報, 117, 464, 19, 24,   2018 03 01 , http://ci.nii.ac.jp/naid/40021521707
  • A scan-path simulation model based on a probabilistic saliency map with receptive field properties of early visual system, 岡崎 那耶, 小濱 剛, 映像情報メディア学会技術報告 = ITE technical report, 42, 7, 13, 16,   2018 03 , http://ci.nii.ac.jp/naid/40021514999
  • An effect of ocular microtremor on vernier acuity based on retinal neuron circuit model considering sampling properties of photoreceptors, 久保 賢典, 小濱 剛, 吉田 久, 映像情報メディア学会技術報告 = ITE technical report, 42, 7, 9, 12,   2018 03 , http://ci.nii.ac.jp/naid/40021514983
  • The effects of aging on drift eye movements, 大谷 尚平, 堺 浩之, 小濱 剛, 映像情報メディア学会技術報告 = ITE technical report, 42, 7, 5, 8,   2018 03 , http://ci.nii.ac.jp/naid/40021514958
  • A scan-path simulation model based on a probabilistic saliency map with receptive field properties of early visul system, 岡崎那耶, 小濱剛, 映像情報メディア学会技術報告, 42, 7(HI2018 44-49/3DIT2018 1-6), 13‐16,   2018 02 28 , http://jglobal.jst.go.jp/public/201802237916189676
  • An effect of ocular microtremor on vernier acuity based on retinal neuron circuit model considering sampling properties of photoreceptors, 久保賢典, 小濱剛, 吉田久, 映像情報メディア学会技術報告, 42, 7(HI2018 44-49/3DIT2018 1-6), 9‐12,   2018 02 28 , http://jglobal.jst.go.jp/public/201802247661261854
  • The effects of aging on drift eye movements, 大谷尚平, 堺浩之, 小濱剛, 映像情報メディア学会技術報告, 42, 7(HI2018 44-49/3DIT2018 1-6), 5‐8,   2018 02 28 , http://jglobal.jst.go.jp/public/201802294784250510
  • Analysis of behaviors by students and page transition (Second report), 渡邊栄治, 尾関孝史, 小濱剛, 電子情報通信学会技術研究報告, 117, 469(ET2017 89-132), 183‐188,   2018 02 24 , http://jglobal.jst.go.jp/public/201802262950746329
  • Analysis of behaviors of audience in presentations (First report), 渡邊栄治, 尾関孝史, 小濱剛, 電子情報通信学会技術研究報告, 117, 464(LOIS2017 71-94), 19‐24,   2018 02 22 , http://jglobal.jst.go.jp/public/201802217713653140
  • A neuronal network model reproducing modulation of visual attention, 正岡明浩, 小濱剛, 小濱剛, 情報処理学会研究報告(Web), 2018, MPS-117, Vol.2018‐MPS‐117,No.11,1‐6 (WEB ONLY),   2018 02 22 , http://jglobal.jst.go.jp/public/201802278114261865
  • Quantitative evaluation of cognitive load by utterance using a dynamic random-dot steering task, NAGANO KAITO, KADONO AYA, MATSUDA KOHTA, KOHAMA TAKESHI, Transactions of Japanese Society for Medical and Biological Engineering, 56, 0, S63, S63,   2018 , http://ci.nii.ac.jp/naid/130007484056
    Summary:<p>With the rapid development of speech recognition technology, voice operation interfaces have been applied to the medical devices. Since It needs to convert the instruction into language information to operate these devices by voice, the cognitive load is not necessarily reduced. The purpose of this study is to quantify the cognitive load by utterance. We measured the performances of a dynamic random-dot steering task, and evaluated the influence of utterance to steering accuracy by simultaneously appending a verbal fluency task. As a result, the amount of steering error under verbal fluency task was larger than under the conditon in which subjects made saccades to peripheral targets. The results indicate that the influence of utterance on the operation accuracy might be caused by attenuation of attention to the visual target. It suggests that the introduction of the voice operation device needs to be examined according to the usage scene.</p>
  • A microsaccade detection method using a recursive neural network, MIYATAKE KAICHI, KOHAMA TAKESHI, YOSHIDA HISASHI, Transactions of Japanese Society for Medical and Biological Engineering, 56, 0, S198, S198,   2018 , http://ci.nii.ac.jp/naid/130007483697
    Summary:<p>It is well known that microsaccades (MSs) reflect cognitive function such as concentration of attention. To detect MSs, a threshold processing to the velocity component of fixation eye movements is generally used. The detection precision of MSs, however, is influenced by the setting of the threshold value. Recent studies have shown that reccurrent neural networks (RNNs) with deep learnig are effective for pattern recognition in time series data. In this study, we applied an RNN to detect MSs. We used a gated reccurrent unit (GRU) with bidirectional RNN structure to avoid long term dependency problem. After identifying MSs from the differentiation signals of the eye movement data and labeling them, we trained the RNN with these time series data. As a result, time periods which include a MS was able to be extracted, and the MSs were classified with an accuracy of 99.34% for 97920 points eye movement data.</p>
  • Age-related changes in fixation eye movements, 大谷 尚平, 堺 浩之, 小濱 剛, 電子情報通信学会技術研究報告 = IEICE technical report : 信学技報, 117, 259, 61, 64,   2017 10 23 , http://ci.nii.ac.jp/naid/40021374085
  • Scan path simulation in free-viewing condition based on a probabilistic saliency map model, 岡崎 那耶, 小濱 剛, 電子情報通信学会技術研究報告 = IEICE technical report : 信学技報, 117, 259, 57, 60,   2017 10 23 , http://ci.nii.ac.jp/naid/40021374077
  • A linear mathematical model of attentional modulation in visual nervous system, 正岡 明浩, 小濱 剛, 電子情報通信学会技術研究報告 = IEICE technical report : 信学技報, 117, 259, 53, 56,   2017 10 23 , http://ci.nii.ac.jp/naid/40021374063
  • An effect of ocular microtremor on vernier acuity based on retinal cone cell layer model, 久保 賢典, 小濱 剛, 電子情報通信学会技術研究報告 = IEICE technical report : 信学技報, 117, 259, 49, 52,   2017 10 23 , http://ci.nii.ac.jp/naid/40021374056
  • An effect of ocular microtremor on vernier acuity based on retinal cone cell layer model, 久保賢典, 小濱剛, 電子情報通信学会技術研究報告, 117, 259(HIP2017 55-80), 49‐52,   2017 10 16 , http://jglobal.jst.go.jp/public/201702221058423019
  • Age-related changes in fixation eye movements, 大谷尚平, 堺浩之, 小濱剛, 電子情報通信学会技術研究報告, 117, 259(HIP2017 55-80), 61‐64,   2017 10 16 , http://jglobal.jst.go.jp/public/201702234775800008
  • A linear mathematical model of attention modulation in visual nervous system, 正岡明浩, 小濱剛, 電子情報通信学会技術研究報告, 117, 259(HIP2017 55-80), 53‐56,   2017 10 16 , http://jglobal.jst.go.jp/public/201702256335476642
  • Scan path simulation in free-viewing condition based on a probabilistic saliency map model, 岡崎那耶, 小濱剛, 電子情報通信学会技術研究報告, 117, 259(HIP2017 55-80), 57‐60,   2017 10 16 , http://jglobal.jst.go.jp/public/201702259219108775
  • Analysis of hand-written notes by students in lectures and self-studies, 渡邊 栄治, 尾関 孝史, 小濱 剛, 電子情報通信学会技術研究報告 = IEICE technical report : 信学技報, 117, 228, 101, 106,   2017 10 05 , http://ci.nii.ac.jp/naid/40021373469
  • Analysis of hand-written notes by students in lectures and self-studies, 渡邊 栄治, 尾関 孝史, 小濱 剛, 映像情報メディア学会技術報告 = ITE technical report, 41, 33, 101, 106,   2017 10 , http://ci.nii.ac.jp/naid/40021381201
  • Analysis of hand-written notes by students in lectures and self-studies, 渡邊栄治, 尾関孝史, 小濱剛, 電子情報通信学会技術研究報告, 117, 228(IE2017 47-63), 101‐106,   2017 09 28 , http://jglobal.jst.go.jp/public/201702221883775631
  • Simulations of Elderly Drivers' Retinal Responses Based on a Mathematical Model of Retinal Neuron Network, 久保賢典, 堺浩之, 内山祐司, 小濱剛, 自動車技術会論文集, 48, 5, 1135‐1141,   2017 09 25 , 10.11351/jsaeronbun.48.1135, http://jglobal.jst.go.jp/public/201702225550780868
  • Analysis of interactions between lecturer and students in lectures, 渡邊 栄治, 尾関 孝史, 小濱 剛, 電子情報通信学会技術研究報告 = IEICE technical report : 信学技報, 117, 209, 29, 34,   2017 09 09 , http://ci.nii.ac.jp/naid/40021342020
  • Analysis of interactions bweteen lecturer and students in lectures, 渡邊栄治, 尾関孝史, 小濱剛, 電子情報通信学会技術研究報告, 117, 209(ET2017 31-39), 29‐34,   2017 09 02 , http://jglobal.jst.go.jp/public/201702266690958761
  • Analysis of behaviors by students corresponding to behaviors by lecturers in lectures(Second report), 渡邊 栄治, 尾関 孝史, 小濱 剛, 電子情報通信学会技術研究報告 = IEICE technical report : 信学技報, 117, 119, 7, 12,   2017 07 07 , http://ci.nii.ac.jp/naid/40021286327
  • Analysis of behaviors by students corresponding to behaviors by lecturers in lectures (Second report), 渡邊栄治, 尾関孝史, 小濱剛, 電子情報通信学会技術研究報告, 117, 119(ET2017 20-30), 7‐12,   2017 06 30 , http://jglobal.jst.go.jp/public/201702268349670170
  • Analysis of noting behaviors by students in video lectures(Second report), 渡邊 栄治, 尾関 孝史, 小濱 剛, 電子情報通信学会技術研究報告 = IEICE technical report : 信学技報, 117, 30, 37, 42,   2017 05 16 , http://ci.nii.ac.jp/naid/40021215506
  • Analysis of noting behaviors by students in video lectures(Second report), 渡邊 栄治, 尾関 孝史, 小濱 剛, 電子情報通信学会技術研究報告 = IEICE technical report : 信学技報, 117, 29, 37, 42,   2017 05 16 , http://ci.nii.ac.jp/naid/40021214452
  • Analysis of noting behaviors by students in video lectures (Second report), 渡邊栄治, 尾関孝史, 小濱剛, 電子情報通信学会技術研究報告, 117, 29(HCS2017 1-46), 37‐42,   2017 05 09 , http://jglobal.jst.go.jp/public/201702257230756108
  • 静的視野検査の測定中に発生する固視微動の解析, 梅原郁美, 若山曉美, 中井裕馬, 小濱剛, 松本長太, 下村嘉一, 日本眼科学会雑誌, 121, 臨増, 254, 254,   2017 03 08 , http://jglobal.jst.go.jp/public/201702238276191019
  • Hemodynamic response measurment of visual cortex based on general linear model analysis for event-related fNIRS signals, 岡本亮太, 小林葵, 小濱剛, 吉田久, 映像情報メディア学会技術報告, 41, 9(HI2017 53-61/3DIT2017 9-17), 25‐28,   2017 03 01 , http://jglobal.jst.go.jp/public/201702240787912813
  • An analysis of steering accuracy and eye movement properties under language fluent tasks, 中井裕真, 小濱剛, 上田慎一, 松田康太, 角野彩, 吉田久, 映像情報メディア学会技術報告, 41, 9(HI2017 53-61/3DIT2017 9-17), 9‐12,   2017 03 01 , http://jglobal.jst.go.jp/public/201702251747406504
  • A saliency estimation model for egocentric motion patterns considering receptive field properties of early visual system and higher order motion detection mechanisms, 小玉光将, 小濱剛, 映像情報メディア学会技術報告, 41, 9(HI2017 53-61/3DIT2017 9-17), 13‐16,   2017 03 01 , http://jglobal.jst.go.jp/public/201702257377812145
  • Hemodynamic response measurement of visual cortex based on general linear model analysis for event-related fNIRS signals, 岡本 亮太, 小林 葵, 小濱 剛, 吉田 久, 映像情報メディア学会技術報告 = ITE technical report, 41, 9, 25, 28,   2017 03 , http://ci.nii.ac.jp/naid/40021162337
  • A saliency estimation model for egocentric motion patterns considering receptive field properties of early visual system and higher order motion detection mechanisms, 小玉 光将, 小濱 剛, 映像情報メディア学会技術報告 = ITE technical report, 41, 9, 13, 16,   2017 03 , http://ci.nii.ac.jp/naid/40021162303
  • An analysis of steering accuracy and eye movement properties under language fluent tasks, 中井 裕真, 小濱 剛, 上田 慎一, 松田 康太, 角野 彩, 吉田 久, 映像情報メディア学会技術報告 = ITE technical report, 41, 9, 9, 12,   2017 03 , http://ci.nii.ac.jp/naid/40021162289
  • 静的視野検査の測定中に発生する固視微動の解析, 梅原 郁美, 若山 曉美, 中井 裕馬, 小濱 剛, 松本 長太, 下村 嘉一, 日本眼科学会雑誌, 121, 臨増, 254, 254,   2017 03
  • マイクロサッカード頻度解析に基づいた音声応答および身体応答に要する認知負荷の定量的比較, 小濱剛, 中井裕真, 大谷尚平, 山本雅也, 上田慎一, 吉田久, ヒューマンインタフェース学会論文誌(CD-ROM), 19, 1-4, 189‐197,   2017 02 25 , http://jglobal.jst.go.jp/public/201802228273571293
  • Simulations of Elderly Drivers' Retinal Responses Based on a Mathematical Model of Retinal Neuron Network, Kubo Kensuke, Sakai Hiroyuki, Uchiyama Yuji, Kohama Takeshi, Transactions of the Society of Automotive Engineers of Japan, 48, 5, 1135, 1141,   2017 , 10.11351/jsaeronbun.48.1135, http://ci.nii.ac.jp/naid/130006734338
    Summary:To investigate the impacts of aging of the retina on visual perception during driving, we simulated retinal responses to traffic scene movies using a large-scale neuronal network model of the aged retina. The model was able to simulate retinal responses within a visual field of 30 deg in diameter. Aging in the retina was characterized by reduced number of retinal cells. Simulation results indicated that necessary information for traffic scene understanding was, at least partially, degraded in the aged retina. Our findings suggest that elderly drivers receive restricted visual information for traffic scene understanding due to age-related decline in retinal function.
  • Analysis of noting behaviors by students in video lectures(Second report), 渡邊 栄治, 尾関 孝史, 小濱 剛, ヒューマンインタフェース学会研究報告集, 19, 37, 42,   2017 , http://ci.nii.ac.jp/naid/40021527065
  • A mathematical model of dynamical properties of microsaccades, Oku Shinsuke, Ohtani Shohei, Kohama Takeshi, Yosida Hisasi, Trans. jpn. Soc. Med. Bio. Eng, 55, 4, 360, 360,   2017 , http://ci.nii.ac.jp/naid/130006077035
    Summary:<p>In this study, we proposed a mathematical to reproduce the dynamic characteristics of microsaccades (MSs). MS is a component of fixation eye movements and occurs involuntarily even when gazing at a specific visual target. We obtained certain length of segments which contain an MS from fixation eye movements, and calculated ensemble averages of them. Since the amplitude of MS varies widely and also changes depending on the shape of fixation target, we categorized the MS amplitude at intervals of 0.3 deg and calculated ensemble averages for each category. As a result, it is shown that dynamic characteristics of MS are described by combination of nonlinear functions which have amplitude, overshoot, and displacement of line of sight as parameters. By combining with conventional model which reproduces the mean square displacement characteristic of fluctuation of</p>
  • Characteristics of Parameters in a Method of Separating fNIRS Signals into Functional and Systemic Components Based on Hemodynamics, Makoto Wauke, Kohama Takeshi, Yoshida Hisashi, Trans. jpn. Soc. Med. Bio. Eng, 55, 3, 219, 219,   2017 , http://ci.nii.ac.jp/naid/130006076992
    Summary:<p>Functional Near-Infrared Spectroscopy, available for higher time resolution than some other methods like fMRI, is widely used for non-invasive neuroimaging. fNIRS enables us to measure consumption of oxygenation occurred by functional activity as hemoglobin density change. However, observed signal is often contaminated by physiological artifact or systemic blood flow changes. Considering these problems, in this study, we have applied the hemodynamical method introduced by Yamada to the observed signal to separate into two modalities, functional and systemic part. We also modified the method to determine coefficients for functional part dynamically because of significant difference between cortex regions activated or not. The modified method has made some functional parts stable and separated global large changes as the systemic parts. Furthermore, all mutual information has been decreased as compared with prior method. The result of this consideration indicates that ideal functional coefficient may vary depending on region or task.</p>
  • Quantitative evaluation of cognitive function based on the event-related fNIRS measurement, Kobayashi Aoi, Okamoto Ryota, Kohama Takeshi, Yoshida Hisashi, Trans. jpn. Soc. Med. Bio. Eng, 55, 3, 220, 220,   2017 , http://ci.nii.ac.jp/naid/130006076991
    Summary:<p>The purpose of this study is to establish a quantitative evaluation method of cognitive functions of brain by functional near-infrared spectroscopy (fNIRS) measurement based on the event related design experiments to reduce artifacts of skin blood flow due to body movements. We measured fNIRS signals while subjects were attending a Posner task to control their attention foci, and analyzed event-related activations which relate to attention allocation. The results show that activations occur around the temporal parietal junction when giving interrupt processing to detect the targets presented at unpredicted places. These results consistent with a result of conventional fMRI study. On the other hand, the effects of interrupt reduce under the condition that the cue has multiple meanings. These results suggest that the higher-order brain functions like attention are able to be evaluated from fNIRS measurement signal based on the event-related design experiments.</p>
  • 〈Original Papers〉A remapping algorithm of visual information between retina and lateral geniculate nucleus, 久保 賢典, 小濱 剛, 吉田 久, 近畿大学生物理工学部紀要 = Memoirs of the Faculty of Biology-Oriented Science and Technology of Kindai University, 38, 11, 20,   2016 10 31 , http://ci.nii.ac.jp/naid/120005983716
    Summary:[要旨] 大脳皮質で認知される感覚情報は,その大部分が視覚に依存することから,認知過程を理解するためには,視覚情報処理過程を明らかにする必要がある.しかしながら,網膜から大脳皮質に至る初期視覚系においても,その処理様式は未だ十分に理解されていない.本研究では,視神経および視索を経て網膜から大脳皮質へと中継する外側膝状体における視覚情報の投射像を得ることを目的として,神経節細胞の時空間応答特性を再現する網膜神経機構モデルに対し,網膜から外側膝状体への投射像を算出するためのリマッピング・アルゴリズムを提案した.提案アルゴリズムにより,網膜モデル出力の投射像を求めた結果,細胞間の位置関係が保たれたまま中心窩方向への細胞の寄せ集めが実現され,視神経束断面における視覚情報表現の可視化ならびに外側膝状体の入力情報を算出するための手段が得られた.[Abstract]Since the majority of the sensory information to the brain is visual information, it is necessary to elucidate the information processes of the visual system to understand the cognitive functions of the brain. However, the neural coding is not yet understood enough even in the early visual system, from retina to primary visual cortex. In this study, we developed a remapping algorithm to calculate the image projection from retina to lateral geniculate nucleus (LGN), in order to visualize the representation of visual information in the early visual system. We used a mathematical model which replicates the characteristics of the dynamics of retinal ganglion cells, and implemented the proposed algorithm to the output layer of this model. Simulation results suggest that the outputs of ganglion cells are gathered toward the central fovea while keeping the retinotopic representation of the visual field. This indicates that proposed algorithm is able to visualize the responses of the optic nerve bundle, which is equivalent to the input of LGN.
  • 網膜神経回路モデルに基づく高齢ドライバの視覚世界再現, 久保賢典, 堺浩之, 内山祐司, 小濱剛, 自動車技術会大会学術講演会講演予稿集(CD-ROM), 2016, ROMBUNNO.102,   2016 10 17 , http://jglobal.jst.go.jp/public/201602242997026811
  • An analysis of spatial sampling properties of peripheral vision based on a retinal neuron network model, 久保 賢典, 小濱 剛, 吉田 久, 電子情報通信学会技術研究報告 = IEICE technical report : 信学技報, 116, 229, 79, 84,   2016 09 27 , http://ci.nii.ac.jp/naid/40020961218
  • Influence of target patterns on dynamic characteristics of fixation eye movements, 大谷 尚平, 小濱 剛, 吉川 昭, 吉田 久, 電子情報通信学会技術研究報告 = IEICE technical report : 信学技報, 116, 229, 61, 66,   2016 09 27 , http://ci.nii.ac.jp/naid/40020961170
  • Influence of target patterns on dynamic characteristics of fixation eye movements, 大谷尚平, 小濱剛, 吉川昭, 吉田久, 電子情報通信学会技術研究報告, 116, 229(HIP2016 42-60), 61‐66,   2016 09 20 , http://jglobal.jst.go.jp/public/201602214440288774
  • An analysis of spatial sampling properties of peripheral vision based on a retinal neuron network model, 久保賢典, 小濱剛, 吉田久, 電子情報通信学会技術研究報告, 116, 229(HIP2016 42-60), 79‐84,   2016 09 20 , http://jglobal.jst.go.jp/public/201602290051623261
  • 独立成分分析を用いたfNIRS計測信号解析手法の検討, 岡本亮太, 小濱剛, 吉田久, センシングフォーラム資料(CD-ROM), 33rd, ROMBUNNO.1A3‐2,   2016 09 01 , http://jglobal.jst.go.jp/public/201602232599064446
  • マイクロサッカードの動的特性と注視視標形状との関係, 大谷尚平, 小濱剛, 吉川昭, 吉田久, センシングフォーラム資料(CD-ROM), 33rd, ROMBUNNO.1A3‐3,   2016 09 01 , http://jglobal.jst.go.jp/public/201602271850307834
  • Relationship between fixation target patterns and dynamic characteristics of microsaccades, 大谷 尚平, 小濱 剛, 吉川 昭, 吉田 久, センシングフォーラム資料, 33, 66, 69,   2016 09 01 , http://ci.nii.ac.jp/naid/40020949874
  • An analyzing method of fNIRS signals based on independent component analysis, 岡本 亮太, 小濱 剛, 吉田 久, センシングフォーラム資料, 33, 62, 65,   2016 09 01 , http://ci.nii.ac.jp/naid/40020949867
  • Analysis of behaviors by students in cooperative learning for video lectures(Second report), 渡邊 栄治, 尾関 孝史, 小濱 剛, 電子情報通信学会技術研究報告 = IEICE technical report : 信学技報, 116, 126, 61, 66,   2016 07 09 , http://ci.nii.ac.jp/naid/40020906968
  • Analysis of behaviors by students in cooperative learning for video lectures (Second report), 渡邊栄治, 尾関孝史, 小濱剛, 電子情報通信学会技術研究報告, 116, 126(ET2016 21-33), 61‐66,   2016 07 02 , http://jglobal.jst.go.jp/public/201602232647068305
  • Analysis of behaviors by participants in brainstorming(Second report), 渡邊 栄治, 尾関 孝史, 小濱 剛, 電子情報通信学会技術研究報告 = IEICE technical report : 信学技報, 116, 60, 81, 86,   2016 05 20 , http://ci.nii.ac.jp/naid/40020850052
  • Analysis of behaviors by participants in meetings for decision making(Second report), 渡邊 栄治, 尾関 孝史, 小濱 剛, 電子情報通信学会技術研究報告 = IEICE technical report : 信学技報, 116, 32, 1, 6,   2016 05 18 , http://ci.nii.ac.jp/naid/40020849657
  • Analysis of behaviors by participants in meetings for decision making(Second report), 渡邊 栄治, 尾関 孝史, 小濱 剛, 電子情報通信学会技術研究報告 = IEICE technical report : 信学技報, 116, 31, 1, 6,   2016 05 18 , http://ci.nii.ac.jp/naid/40020849113
  • Analysis of behaviors by participants in brainstorming (Second report), 渡邊栄治, 尾関孝史, 小濱剛, 電子情報通信学会技術研究報告, 116, 60(ET2016 1-7), 81‐86,   2016 05 13 , http://jglobal.jst.go.jp/public/201602291630938717
  • Analysis of behaviors by participants in meetings for decision making (Second report), 渡邊栄治, 尾関孝史, 小濱剛, 電子情報通信学会技術研究報告, 116, 32(HIP2016 1-30), 1‐6,   2016 05 11 , http://jglobal.jst.go.jp/public/201602274138393524
  • Relationships between noting behaviors and evaluation for notes taken by students for video lectures, 渡邊 栄治, 尾関 孝史, 小濱 剛, 電子情報通信学会技術研究報告 = IEICE technical report : 信学技報, 115, 492, 81, 86,   2016 03 05 , http://ci.nii.ac.jp/naid/40020790668
  • 不同視弱視症例における左右眼の固視微動の比較, 白井久美, 田中公子, 小久保奈津, 加納悠史, 中井裕真, 小濱剛, 雑賀司珠也, 日本眼科学会雑誌, 120, 臨増, 320, 320,   2016 03 02 , http://jglobal.jst.go.jp/public/201602203093467421
  • A gaze prediction model for scan-path simulation of free-viewing, 吉野宏紀, 小濱剛, 映像情報メディア学会技術報告, 40, 9(HI2016 42-50/3DIT2016 1-9), 17‐20,   2016 03 01 , http://jglobal.jst.go.jp/public/201602205034721112
  • A visual search simulation by a neuron network model of visual attention, 前田侑大, 正岡明浩, 小濱剛, 映像情報メディア学会技術報告, 40, 9(HI2016 42-50/3DIT2016 1-9), 21‐24,   2016 03 01 , http://jglobal.jst.go.jp/public/201602206889391019
  • An analyses of characteristics of fixational eye movements in amblyopia, 加納悠史, 中井裕真, 大谷尚平, 田中公子, 白井久美, 小濱剛, 雑賀司珠也, 吉田久, 映像情報メディア学会技術報告, 40, 9(HI2016 42-50/3DIT2016 1-9), 9‐12,   2016 03 01 , http://jglobal.jst.go.jp/public/201602215199433656
  • Inhibition effects on resting fNIRS signals of prefrontal cortex by dynamic random-dot patterns, 並河弘樹, 岡本亮太, 柴田はるな, 小濱剛, 吉田久, 映像情報メディア学会技術報告, 40, 9(HI2016 42-50/3DIT2016 1-9), 13‐16,   2016 03 01 , http://jglobal.jst.go.jp/public/201602216481086248
  • A visual search simulation by a neuron network model of visual attention, MAEDA Yuta, MASAOKA Akihiro, KOHAMA Takeshi, ITE Technical Report, 40, 9, 21, 24,   2016 03 , http://ci.nii.ac.jp/naid/110010044745
    Summary:In this study, we proposed a mathematical model of neuron network which concerns the control of visual attention, in order to understand the information processing of the visual system during visual search. Since bottom-up and top-down attention cooperatively perform during visual search tasks, the proposed model was constructed to have a network of bottom-up attention and integrate bottom-up and top-down processes to select a visual target based on the previous model which is able to replicate behaviors of top-down attention. Simulation results show that our model replicates the physiological evidence of neuron activities and the characteristic of eye movements during visual search tasks.
  • A gaze prediction model for scan-path simulation of free-viewing, YOSHINO Hiroki, KOHAMA Takeshi, ITE Technical Report, 40, 9, 17, 20,   2016 03 , http://ci.nii.ac.jp/naid/110010044744
    Summary:In the processes of gaze shifts on a visual object, cooperative behaviors of bottom-up attention and top-down attention are concerned. Gaze shifts during free-viewing without a specific purpose depend on the saliency of visual information and show object selections in accordance with visual contexts. This property suggests that there might be a medial processes between bottom-up and top-down attention. In this study, a gaze prediction model was proposed in order to understand a mechanism of gaze shifts in free-viewing. We extended a previous model which considers conditional provability to have a weighting based on a principal component analysis of scan-path data while viewing natural images freely, and evaluated prediction accuracy of gaze position in free-viewing. Simulation results indicate that the accuracy of prediction of proposed model is better than that of previous model, which suggest the ability of the model to provide gaze prediction considering individual differences.
  • An analyses of characteristics of fixational eye movements in amblyopia, KANOH Yuji, NAKAI Yuma, OHTANI Shohei, TANAKA Hiroko, SHIRAI Kumi, KOHAMA Takeshi, SAIKA Shizuya, YOSHIDA Hisashi, ITE Technical Report, 40, 9, 9, 12,   2016 03 , http://ci.nii.ac.jp/naid/110010044742
    Summary:It is known that amblyopia could be improved by sight training such as visual attention concentration tasks. However, the effectiveness of sight training could not evaluate objectively because amblyopia is not fully understood so far. Since visual attention influences on fixation eye movements, which are involuntary miniature movements of the eye, there is a possibility that the properties of fixation eye movements would change by sight training. In order to investigate the characteristics of fixation eye movements of amblyopic eye, we carried out an experiment which maintain visual fixation during focal attention tasks. The results of analyses of fixation eye movements suggest that microsaccade rate and microsaccade amplitude are both higher than those of normal eyes. Moreover, frequency analysis of drift eye movements indicate that the amplitude of fluctuation in low frequency component of amblyopic eyes is larger than that of normal eyes.
  • Inhibition effects on resting fNIRS signals of prefrontal cortex by dynamic random-dot patterns, NAMIKAWA Hiroki, OKAMOTO Ryota, SHIBATA Haruna, KOHAMA Takeshi, YOSHIDA Hisashi, ITE Technical Report, 40, 9, 13, 16,   2016 03 , http://ci.nii.ac.jp/naid/110010044743
    Summary:In the measurement of the functional near-infrared spectroscopy (fNIRS), the difference between resting state and task-performing state is often evaluated as an index of brain activities. However, since the definition of resting-state is ambiguous, the experimental conditions of resting state are not controlled, and this makes individual differences of experimental data enlarged. In this study, we investigate the condition to be recovered to resting state earlier during a recovery process after brain activation. We compared the brain activity of prefrontal cortex (PFC) while gazing at a low-passed dynamic random-dot pattern (DRD) or a fixation crosshair after performing a 3-back task. The results suggest that the averaged activities of PFC in the DRD condition were significantly lower than the FT condition.
  • Relationships between noting behaviors and evaluation for notes taken by students for video lectures, 渡邊栄治, 尾関孝史, 小濱剛, 電子情報通信学会技術研究報告, 115, 492(ET2015 93-147), 81‐86,   2016 02 27 , http://jglobal.jst.go.jp/public/201602253065142122
  • 個人利用を目的とした音楽の印象に適した画像の選定:設計システムの改良, 長谷川優, 武田昌一, 小濱剛, 吉田久, 日本感性工学会大会予稿集(CD-ROM), 18th, ROMBUNNO.A33,   2016 , http://jglobal.jst.go.jp/public/201602249830923212
  • 個人利用を目的とした音楽の印象に適した画像の選定:システム設計とテスト運用, 長谷川優, 武田昌一, 小濱剛, 吉田久, 日本感性工学会春季大会予稿集(CD-ROM), 11th, ROMBUNNO.G6‐7,   2016 , http://jglobal.jst.go.jp/public/201602278765204032
  • Inhibition effects of fNIRS signals of prefrontal cortex by low-passed dynamic random-dot patterns, Kohama Takeshi, Namikawa Hiroki, Okamoto Ryota, Yoshida Hisashi, Transactions of Japanese Society for Medical and Biological Engineering, 54, 28, S273, S273,   2016 , http://ci.nii.ac.jp/naid/130005285428
    Summary:<p>In the measurement techniques of cortical activity by using the functional near-infrared spectroscopy (fNIRS), the differences between resting state and task-performing state is often evaluated. However, the experimental conditions of resting state are not controlled. In this study, we investigated the effects of the low-passed dynamic random-dot patterns (LPDRDs) on the resting-state activities. We measured fNIRS signals from prefrontal cortex (PFC) and right-lateral temporal cortex (rLTC) during a block design paradigms, which is constructed of resting-state block with a LPDRD or a fixation crosshair (FT) after performing a 3-back task. We compared which condition is to be recovered to resting-state earlier after brain activation by the task. The results suggest that the average activity of PFC in the LPDRD condition was significantly lower than in the FT condition, indicating that gazing at the LPDRD in resting-state could be attenuated cortical activity more efficiently.</p>
  • The effects of fixation target pattern on dynamic characteristics of microsaccades, Ohtani Shohei, Nakai Yuma, Kanoh Yuji, Kohama Takeshi, Kikkawa Sho, Yoshida Hisashi, Transactions of Japanese Society for Medical and Biological Engineering, 54, 26, S43, S43,   2016 , http://ci.nii.ac.jp/naid/130005285102
    Summary:<p>Microsaccades are rapid and involuntary fixation eye movements. Previous studies have shown that shapes of fixation targets affect microsaccades rate. However, other characteristics of microsaccades have not been analyzed. Here, we investigated the relationship between target shapes and characteristics of microsaccades. Subjects gazed at one of the seven targets, which was composed from a point, a circle, and a cross, for 10 sec. The results indicate that the relationship between amplitude and peak-velocity of microsaccade had no correlation with target shapes, while there were some pairings that have significant differences in the relation between amplitude and frequency. The differences between point-only or point-and-cross target and circle target were salient. When point-only or point-and-cross target was presented, amplitude became small and frequency increased. They were reversed when circle target was presented. These results suggest that microsaccades are controlled to maintain the integration value of amplitude and frequency.</p>
  • An examination of application technique of independent component analysis for fNIRS signals, Okamoto Ryota, Namikawa Hiroki, Shibata Haruna, Kohama Takeshi, Yoshida Hisashi, Transactions of Japanese Society for Medical and Biological Engineering, 54, 26, S42, S42,   2016 , http://ci.nii.ac.jp/naid/130005285096
    Summary:<p>A measurement technique of brain activity using fNIRS is drawing attention. The contamination of skin blood flow (SBF) is often interpreted as brain activities in fNIRS measurements, which makes the reliability of fNIRS studies uncertain. The independent component analysis (ICA) is frequently applied to decrease the SBF artifacts. However, there is not an appropriate criterion to determine which independent components contain meaningful features. Here, we proposed a criterion based on a cross-correlation coefficient (CCC) and a coefficient of spatial uniformity (CSU). fNIRS signals were measured while subjects utter vowels rhythmically while measuring SBF simultaneously. The result indicates that many channels contain SBF artifacts and show strong correlation with uttering. We applied an ICA to pseudo fNIRS signals, which generated by using SBF signals measured in an uttering task. The results suggest that brain activity is properly extracted by using CCC and CSU, unless SBF has a correlation with brain activities.</p>
  • Relationships between understandings and non-verbal behaviors by students for video lectures, 渡邊 栄治, 尾関 孝史, 小濱 剛, 電子情報通信学会技術研究報告 = IEICE technical report : 信学技報, 115, 352, 1, 6,   2015 12 04 , http://ci.nii.ac.jp/naid/40020701100
  • Relationships between understandings and non-verbal behaviors by students for video lectures, 渡邊 栄治, 尾関 孝史, 小濱 剛, 電子情報通信学会技術研究報告 = IEICE technical report : 信学技報, 115, 351, 1, 6,   2015 12 04 , http://ci.nii.ac.jp/naid/40020700753
  • 汎用モーションセンサーによる要介護高齢者のトレーニングでのADL基本動作の変容, 藤田英二, 岡田壮市, 小濱剛, 楠正暢, 長谷川太一, 竹島伸生, 体力科学, 64, 6, 735, 735,   2015 12 , http://jglobal.jst.go.jp/public/201602215797884158
  • デイケア利用者の油圧マシントレーニングによる運動効果, 岡田壮市, 岡田壮市, 岡田壮市, 藤田英二, 小濱剛, 楠正暢, 成田誠, 加藤芳司, 竹島伸生, 竹島伸生, 体力科学, 64, 6, 730, 730,   2015 12 , http://jglobal.jst.go.jp/public/201602221160530131
  • 虚弱高齢者のためのADL客観的指標の作成に関する研究(その1), 竹島 伸生, 岡田 壮市, 楠 正暢, 小濱 剛, 藤田 英二, 長谷川 太一, 体力科学, 64, 6, 729, 729,   2015 12 , 10.7600/jspfsm.64.729, http://jglobal.jst.go.jp/public/201602205497206101
  • 汎用モーションセンサによる虚弱高齢者のADL評価システム開発のための情報取得時の測定誤差に関する検討, 楠 正暢, 小濱 剛, 岡田 壮市, 藤田 英二, 竹島 伸生, 体力科学, 64, 6, 729, 729,   2015 12 , 10.7600/jspfsm.64.729, http://jglobal.jst.go.jp/public/201602206316972882
  • Relationships between understandings and non-verbal behaviors by students for video lectures, 渡邊栄治, 尾関孝史, 小濱剛, 電子情報通信学会技術研究報告, 115, 351(SITE2015 41-55), 1‐6,   2015 11 27 , http://jglobal.jst.go.jp/public/201602204437915271
  • Analysis of behaviors by participants in meetings for decision making, 渡邊 栄治, 尾関 孝史, 小濱 剛, 電子情報通信学会技術研究報告 = IEICE technical report : 信学技報, 115, 237, 89, 94,   2015 10 02 , http://ci.nii.ac.jp/naid/40020649937
  • A mathematical model of retina considering the characteristics of the distribution of photoreceptor and ganglion cells, 久保 賢典, 小濱 剛, 吉田 久, 電子情報通信学会技術研究報告 = IEICE technical report : 信学技報, 115, 232, 55, 60,   2015 09 28 , http://ci.nii.ac.jp/naid/40020617243
  • Analysis of behaviors by participants in meetings for decision making, 渡邊栄治, 尾関孝史, 小濱剛, 電子情報通信学会技術研究報告, 115, 237(HCS2015 55-58), 89‐94,   2015 09 25 , http://jglobal.jst.go.jp/public/201502205976740425
  • The effects of cognitive loads derived from voice or manual responses on microsaccade rate, NAKAI YUUMA, OTANI SHOHEI, KANO YUJI, YAMAMOTO MASAYA, UEDA SHIN'ICHI, KURIHARA MASAYUKI, KOHAMA TAKESHI, YOSHIDA HISASHI, 電子情報通信学会技術研究報告, 115, 232(HIP2015 72-87), 79, 84,   2015 09 21 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201502209473210726
  • A mathematical model of retina considering the characteristics of the distribution of photoreceptor and ganglion cells, KUBO KENSUKE, KOHAMA TAKESHI, YOSHIDA HISASHI, 電子情報通信学会技術研究報告, 115, 232(HIP2015 72-87), 55, 60,   2015 09 21 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201502211079079694
  • Analysis of behaviors by participants in brainstorming, WATANABE EIJI, OZEKI TAKASHI, KOHAMA TAKESHI, 映像情報メディア学会技術報告, 39, 31(AIT2015 98-105), 9, 12,   2015 08 24 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201502212953875460
    Summary:In brainstorming, participants have to keep some important rules; (i) do not deny any proposals, (ii) do propose more proposals. Therefore, the evaluation by the participant for proposals can be represented by the non-verbal behaviors by participants. In this report, we propose image processing methods for the detection of non-verbal behaviors by participants. Moreover, we propose an evaluation method for the activity of the brainstorming. Finally, we discuss the relationship between the proposed activity and the review result by the participant.
  • Relationships between understandings and noting behaviors by students for video lectures, 渡邊 栄治, 尾関 孝史, 小濱 剛, 電子情報通信学会技術研究報告 = IEICE technical report : 信学技報, 115, 149, 25, 30,   2015 07 18 , http://ci.nii.ac.jp/naid/40020557351
  • Recording and reproducing of noting behaviors by image processing, 渡邊 栄治, 尾関 孝史, 小濱 剛, 電子情報通信学会技術研究報告 = IEICE technical report : 信学技報, 115, 138, 1, 6,   2015 07 13 , http://ci.nii.ac.jp/naid/40020557804
  • Relationships between understandings and noting behaviors by students for video lectures, WATANABE EIJI, OZEKI TAKASHI, KOHAMA TAKESHI, 電子情報通信学会技術研究報告, 115, 149(HIP2015 41-71), 25, 30,   2015 07 11 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201502203946761190
  • Recording and reproducing of noting behaviors by image processing, WATANABE EIJI, OZEKI TAKASHI, KOHAMA TAKESHI, 電子情報通信学会技術研究報告, 115, 138(LOIS2015 9-17), 1, 6,   2015 07 06 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201502211933921310
  • Analysis of writing behaviors by learners in solving process for problems, 渡邊 栄治, 尾関 孝史, 小濱 剛, 電子情報通信学会技術研究報告 = IEICE technical report : 信学技報, 115, 127, 1, 6,   2015 07 04 , http://ci.nii.ac.jp/naid/40020557574
  • Analysis of writing behaviors by learners in solving process for problems, WATANABE EIJI, OZEKI TAKASHI, KOHAMA TAKESHI, 電子情報通信学会技術研究報告, 115, 127(ET2015 23-31), 1, 6,   2015 06 27 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201502202722992522
  • Relations between behaviors and evaluation by interviewer in interviews, 渡邊 栄治, 尾関 孝史, 小濱 剛, 聴覚研究会資料 = Proceedings of the auditory research meeting, 45, 4, 329, 334,   2015 06 18 , http://ci.nii.ac.jp/naid/40020533053
  • Relations between behaviors and evaluation by interviewer in interviews, 渡邊 栄治, 尾関 孝史, 小濱 剛, 電子情報通信学会技術研究報告 = IEICE technical report : 信学技報, 115, 100, 125, 130,   2015 06 18 , http://ci.nii.ac.jp/naid/40020524717
  • Relations between behaviors and evaluation by interviewer in interviews, 渡邊 栄治, 尾関 孝史, 小濱 剛, 電子情報通信学会技術研究報告 = IEICE technical report : 信学技報, 115, 99, 125, 130,   2015 06 18 , http://ci.nii.ac.jp/naid/40020524259
  • Relations between behaviors and evaluation by interviewer in interviews, 渡邊 栄治, 尾関 孝史, 小濱 剛, 電子情報通信学会技術研究報告 = IEICE technical report : 信学技報, 115, 98, 125, 130,   2015 06 18 , http://ci.nii.ac.jp/naid/40020523497
  • Relations between behaviors and evaluation by interviewer in interviews, WATANABE EIJI, OZEKI TAKASHI, KOHAMA TAKESHI, 電子情報通信学会技術研究報告, 115, 100(WIT2015 1-35), 125, 130,   2015 06 11 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201502205724957294
  • Analysis of behaviors by students corresponding to behaviors by lecturers in lectures, 渡邊 栄治, 尾関 孝史, 小濱 剛, 電子情報通信学会技術研究報告 = IEICE technical report : 信学技報, 115, 36, 85, 90,   2015 05 19 , http://ci.nii.ac.jp/naid/40020491784
  • Analysis of behaviors by students corresponding to behaviors by lecturers in lectures, 渡邊 栄治, 尾関 孝史, 小濱 剛, 電子情報通信学会技術研究報告 = IEICE technical report : 信学技報, 115, 35, 85, 90,   2015 05 19 , http://ci.nii.ac.jp/naid/40020491296
  • Analysis of behaviors by students corresponding to behaviors by lecturers in lectures, WATANABE EIJI, OZEKI TAKASHI, KOHAMA TAKESHI, 電子情報通信学会技術研究報告, 115, 36(HIP2015 1-40), 85, 90,   2015 05 12 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201502209502782432
  • Relationships between the behaviors by lecturer and students in lectures, WATANABE Eiji, OZEKI Takashi, KOHAMA Takeshi, IEICE technical report. Education technology, 114, 513, 33, 38,   2015 03 14 , http://ci.nii.ac.jp/naid/110010021570
    Summary:In this report, we discuss the influence on the behavior by lecturer. First, we extract the face movements by lecturer and students from movies. Next, the relations among the above features concerning on the behaviors by the lecturer and students can be approximated by multi-layered neural networks. Finally, we extract the influence on the behavior by the lecturer based on the internal representations of neural networks.
  • Relationships between the behaviors by lecturer and students in lectures, WATANABE EIJI, OZEKI TAKASHI, KOHAMA TAKESHI, 電子情報通信学会技術研究報告, 114, 513(ET2014 85-117), 33, 38,   2015 03 07 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201502279948192083
  • Quantitative assessments of arousal level by analyzing fixation eye movements and pupil fluctuations, HONDA SHOGO, KOHAMA TAKESHI, YOSHIDA HISASHI, 映像情報メディア学会技術報告, 39, 11(HI2015 45-55/3DIT2015 11-21), 25, 28,   2015 03 03 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201502298928131112
    Summary:Previous studies have shown that microsaccade (MS) rates increase and pupil diameters continuously constrict antecedent to the occurrence of slow eye movements (SEMs). Since SEMs occur in connection with the depression of arousal, fixation eye movements and pupil fluctuations are candidate indicators to monitor arousal states. However, SEM detection methods of these studies are not sufficiently accurate. In this study, we propose a new SEM detection method to extract SEMs as sections and analyze MS rates and pupil fluctuations before the starting point of each SEM section. The results clearly show that gradual rise of MS rate and longitudinal miosis are observed prior to the initiation of SEMs, and these properties become more distinctive when they are restricted to primal SEMs. Moreover, we performed similar experiment using more precise equipment and the results show that periodical MS rate heave associated with nystagmus appears approximately two minutes prior to SEMs. This indicates that these profiles might be able to be used to estimate arousal states quantitatively.
  • A verification of moduration of visual perception caused by fixation eye movements based on a model of retinae, NISHINO Makoto, KOHAMA Takeshi, YOSHIDA Hisashi, ITE Technical Report, 39, 11, 17, 20,   2015 03 03 , http://ci.nii.ac.jp/naid/110009923293
    Summary:In this study, we performed a simulation experiments using a mathematical model of a wide-scale retinal network considering the receptive fields' properties in parafovea. Vertical sinusoidal grating patterns and random dot patterns, which consist of particular spacial frequencies, were given as input patterns. We computed the retinal ganglion cells responses which were composed of either a high or a low spacial frequency. Simulation results of grating pattern input suggest that microsaccades enhance the membrane potential of ganglion cells for the low-frequency pattern, and as for the high-frequency patten, it is influenced by drifts and tremor, particularly on the responses of M-type cells under both conditions. On the other hand, they do not influence the activity of M- or P-type cells when any random dot pattern inputs was given. These results suggest that the strength of the effects derived by fixation eye movements on the retinal responses depend on the nature of the input patterns.
  • A mathematical model for reproducing stochastic properties of fixation eye movements, TOKUDOME Ken, KOHAMA Takeshi, KIKKAWA Sho, YOSHIDA Hisashi, ITE Technical Report, 39, 11, 21, 24,   2015 03 03 , http://ci.nii.ac.jp/naid/110009923294
    Summary:In this study, we propose a mathematical model of fixation eye movements controlled by visual attention mechanisms to establish an index for quantitative evaluation of higher-order cognitive functions. It is known that Mean Square Displacement (MSD) profiles of fixation eye movements show a crossover phenomenon (Engbert & Kliegl. 2004), which indicates that multiple external factors contribute to control of movements. We formulated a model based on a hypothesis that stable gazing is controlled by rectifying retinal errors by drifts and microsaccades. Simulation results suggest that fractional Brownian motion and continuous feedback to correct gaze positions yield the MSD profile of fixation eye movements. Furthermore, microsaccades contribute to modulate the MSD profile during short-range lags.
  • 汎用モーションセンサを用いた高齢者のADL評価システムの試み, KOHAMA TAKESHI, KUSUNOKI MASANOBU, OKADA SOICHI, TAKESHIMA NOBUO, 体力科学, 64, 1, 12, 12,   2015 02 , 10.7600/jspfsm.64.12, http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201502231666991029
  • Relations between behaviors by interviewee and interviewer in interviews, WATANABE Eiji, OZEKI Takashi, KOHAMA Takeshi, IEICE technical report. Life intelligence and office information systems, 114, 390, 97, 102,   2015 01 15 , http://ci.nii.ac.jp/naid/110010009858
    Summary:In interviews, the evaluation by the interviewer is affected by not only the reply by the interviewee but also behaviors (eye and face movements) by interviewee. Moreover, the evaluation by the interviewer is communicated with the interviewee and the interaction between the behaviors by the interviewer and the interviewee occurs. In this paper, we show that the evaluation by the interviewer is strongly influenced by behaviors by interviewee.
  • Relations between behaviors by interviewee and interviewer in interviews, WATANABE Eiji, OZEKI Takashi, KOHAMA Takeshi, IEICE technical report. Information and communication management, 114, 389, 97, 102,   2015 01 15 , http://ci.nii.ac.jp/naid/110010001761
    Summary:In interviews, the evaluation by the interviewer is affected by not only the reply by the interviewee but also behaviors (eye and face movements) by interviewee. Moreover, the evaluation by the interviewer is communicated with the interviewee and the interaction between the behaviors by the interviewer and the interviewee occurs. In this paper, we show that the evaluation by the interviewer is strongly influenced by behaviors by interviewee.
  • Relations between behaviors by interviewee and interviewer in interviews, WATANABE EIJI, OZEKI TAKASHI, KOHAMA TAKESHI, 電子情報通信学会技術研究報告, 114, 389(ICM2014 32-53), 97, 102,   2015 01 08 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201502274908256435
  • マイクロサッカード潜時解析に基づく音声および身体応答による認知負荷の客観的評価, 中井裕真, 加納悠史, 上田慎一, 栗原正幸, 岩崎健二, 小濱剛, 吉田久, 日本生体医工学会大会プログラム・論文集(CD-ROM), 54th, 391‐392,   2015 , http://jglobal.jst.go.jp/public/201602241335654010
  • NIRSによる安静時機能的結合推定のための計測条件の検討, 岡本亮太, 並河弘樹, 小濱剛, 吉田久, 日本生体医工学会大会プログラム・論文集(CD-ROM), 54th, 377‐378,   2015 , http://jglobal.jst.go.jp/public/201602276490854448
  • An objective evaluation of cognitive loads of voice and manual responses based on the analysis of microsaccade latencies, NAKAI YUMA, KANOH YUJI, UEDA SHINICHI, KURIHARA MASAYUKI, IWASAKI KENJI, KOHAMA TAKESHI, YOSHIDA HISASHI, Transactions of Japanese Society for Medical and Biological Engineering, 53, 0, S166_03, S166_03,   2015 , http://ci.nii.ac.jp/naid/130005163738
    Summary:Applications of voice recognition technologies redound to carnavigation systems or mobile phones. However, cognitive-loads of voiceoperations are not discussed sufficiently. Because it is necessary totranslate a command to a verbal phrase, cognitive-loads of voiceoperations for simple tasks may become higher than those of manualoperations. In this study, we analyzed microsaccades, which are an indicator of by cognitive-loads such as attention concentration, to compare the loads between voice and manual operations objectively. Subjects performed a peripheral transition detection taskof a geometry pattern in which they responded by their voice or mouseclicks. Subjects were instructed to respond with the voice of &ldquo;A&rdquo; or &ldquo;I&rdquo; correspond to the transformation of the peripheral pattern. Theresults suggest that accuracy of detection and averaged response timeshow no significant difference between two conditions. On the otherhand, the distributions of latency of the first microsaccades showbiases immediately before or after the responses only on a voiceresponse condition. These results suggest that visual attention mightbe disengaged at the timings of response under the oral condition.
  • A measurement condition for estimation of resting-state functional connectivity using NIRS, OKAMOTO RYOTA, Namikawa Hiroki, Kohama Takeshi, Yoshida Hisashi, Transactions of Japanese Society for Medical and Biological Engineering, 53, 0, S163_03, S163_03,   2015 , http://ci.nii.ac.jp/naid/130005163728
    Summary:Functional connectivity in resting state has became the dominant way of understanding brain functions. However, the definition of resting states is ambiguous. A previous study have shown that low-passed dynamic random-dot patterns (DRDs) have some effects on controlling resting state, but it has not been verified enough. The purpose of this study is to define the brain activity derived from observation of DRDs. We measured NIRS signals from subjects' prefrontal cortex (PFC) and right-lateral temporal cortex (rLTC) during a block design paradigm which composed from iteration of cross hairs target and a DRD. Subjects were instructed to maintain their gaze on the cross target and to think nothing as much as possible. The DRDs were filtered by three types of Gaussian filters. As a result, the activities of ventrolateral PFC and rLTC significantly decreased when the display had been switched from the cross target to the DRD, and the effects were more intense as blurriness of DRDs increased. This suggests that observation of DRDs could be able to inhibit mind wandering and to derive attention disengagement, because these brain areas are associated with default mode network and working memory.
  • A measurement condition for estimation of resting-state functional connectivity using NIRS, OKAMOTO Ryota, NAMIKAWA Hiroki, KOHAMA Takeshi, YOSHIDA Hisashi, Transactions of Japanese Society for Medical and Biological Engineering, 53, 0, S377, S378,   2015 , http://ci.nii.ac.jp/naid/130005157998
    Summary:Functional connectivity in resting state has became the dominantway of understanding brain functions. However, the definition of resting states is ambiguous. A previous study have shown that low-passed dynamic random-dot patterns (DRDs) have some effects on controlling resting state, but it has not been verified enough. The purpose of this study is to define the brain activity derived from observation of DRDs. We measured NIRS signals from subjects' prefrontal cortex (PFC) and right-lateral temporal cortex (rLTC) during a block design paradigm which composed from iteration of cross hairs target and a DRD. Subjects were instructed to maintain their gaze on the cross target and to think nothing as much as possible. The DRDs were filtered by three types of Gaussian filters. As a result, the activities of ventrolateral PFC and rLTC significantly decreased when the display had been switched from the cross target to the DRD, and the effects were more intense as blurriness of DRDs increased. This suggests that observation of DRDs could be able to inhibit mind wandering and to derive attention disengagement, because these brain areas are associated with defaultmode network and working memory.
  • An objective evaluation of cognitive loads of voice and manual responses based on the analysis of microsaccade latencies, NAKAI Yuma, KANOH Yuji, UEDA Shinichi, KURIHARA Masayuki, IWASAKI Kenji, KOHAMA Takeshi, YOSHIDA Hisashi, Transactions of Japanese Society for Medical and Biological Engineering, 53, 0, S391, S392,   2015 , http://ci.nii.ac.jp/naid/130005157992
    Summary:Applications of voice recognition technologies redound to car navigation systems or mobile phones. However, cognitive-loads of voice operations are not discussed sufficiently. Because it is necessary to translate a command to a verbal phrase, cognitive-loads of voice operations for simple tasks may become higher than those of manual operations. In this study, we analyzed microsaccades, which are an indicator of by cognitive-loads such as attention concentration, to compare the loads between voice and manual operations objectively. Subjects performed a peripheral transition detection task of a geometry pattern in which they responded by their voice or mouse clicks. Subjects were instructed to respond with the voice of "A" or "I" correspond to the transformation of the peripheral pattern. The results suggest that accuracy of detection and averaged response time show no significant difference between two conditions. On the other hand, the distributions of latency of the first microsaccades show biases immediately before or after the responses only on a voice response condition. These results suggest that visual attention might be disengaged at the timings of response under the oral condition.
  • 個人の音楽嗜好に着目した音楽に適合した画像の選定に関するフィルタ設計, HASEGAWA YU, TAKEDA SHOICHI, KOHAMA TAKESHI, YOSHIDA HISASHI, 日本感性工学会大会予稿集(CD-ROM), 17th, ROMBUNNO.F32,   2015 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201502215910475629
  • パーソナルユースを目的とした音楽に適した画像の選定に関する概念モデル, HASEGAWA YU, TAKEDA SHOICHI, KOHAMA TAKESHI, YOSHIDA HISASHI, 日本感性工学会春季大会予稿集(CD-ROM), 10th, ROMBUNNO.2C-02,   2015 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201502244572771062
  • 11-14 A saliency estimation model for motion images with visual adaptation property, KODAMA Mitsuhiro, KOHAMA Takeshi, ITE Winter Annual Convention, 2014, 2014, 11, 14-1"-"11-14-1",   2014 12 17 , http://ci.nii.ac.jp/naid/110009933767
  • 8-5 Quantitative evaluation of cognitive loads of voice or manual responses based on eye fixation analyses, NAKAI Yuma, KANOH Yuji, UEDA Shinichi, KURIHARA Masayuki, IWASAKI Kenji, KOHAMA Takeshi, ITE Winter Annual Convention, 2014, 2014, 8, 5-1"-"8-5-1",   2014 12 17 , http://ci.nii.ac.jp/naid/110009933735
  • 視覚的順応特性を考慮した動画像に対する顕著性推定モデル, KODAMA MITSUHIRO, KOHAMA TAKESHI, 映像情報メディア学会冬季大会講演予稿集(CD-ROM), 2014, ROMBUNNO.11-14,   2014 11 26 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201502203479950226
  • 固視微動解析に基づく音声応答および身体応答に対する認知負荷の客観的評価, NAKAI YUUMA, KANO YUJI, UEDA SHIN'ICHI, KURIHARA MASAYUKI, IWASAKI KENJI, KOHAMA TAKESHI, 映像情報メディア学会冬季大会講演予稿集(CD-ROM), 2014, ROMBUNNO.8-5,   2014 11 26 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201502228713591955
  • Analysis of behaviors by lecturer in lectures, WATANABE Eiji, HIGASHI Takuya, OZEKI Takashi, KOHAMA Takeshi, ITE Technical Report, 38, 46, 61, 64,   2014 11 21 , http://ci.nii.ac.jp/naid/110009885413
    Summary:In this report, we discuss the influence on the behavior by the lecturer. First, we extract the face movements by lecturer and students from movies. Next, the relations among the above features concerning on the behaviors by the lecturer and students can be approximated by multi-layered neural networks. Finally, we extract the influence on the behavior by the lecturer based on the internal representations of neural networks.
  • Analysis of nodding behaviors by interviewer and interviewee in interviews, WATANABE EIJI, OZEKI TAKASHI, KOHAMA TAKESHI, 電子情報通信学会技術研究報告, 114, 273(HCS2014 60-72), 7, 12,   2014 10 16 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201402218169118555
  • Analysis of nodding behaviors by interviewer and interviewee in interviews, WATANABE Eiji, OZEKI Takashi, KOHAMA Takeshi, Technical report of IEICE. HCS, 114, 273, 7, 12,   2014 10 16 , http://ci.nii.ac.jp/naid/110009959573
    Summary:In interviews, the evaluation by the interviewer is affected by not only the reply by the interviewee but also behaviors (eye and face movements) by interviewee. Especially, the nodding behavior has the function for the confirmation of the reply and the question for the interviewer and the interviewee. In this paper, we discuss the relation between the evaluation of the interview and the nodding behaviors by the interviewer and the interviewee.
  • Quantitative measurements of attentional concentration based on analyses of microsaccades and drift eye movements, KOHAMA Takeshi, KIKKAWA Sho, YOSHIDA Hisashi, Technical report of IEICE. HIP, 114, 226, 87, 92,   2014 09 25 , http://ci.nii.ac.jp/naid/110009950336
    Summary:The purpose of this study is to evaluate the effect of visual attention on the dynamics of fixation eye movements objectively. We carried out experiments which control the subjects' focal attention. A signal processing method was proposed to separate microsaccades and drift eye movements from fixation eye movements, and compared the properties of microsaccade rate and dynamics of drift eye movements among the conditions of atten-tional intensities. The results show that the microsaccade rate was suppressed and the histogram of latencies of microsaccades have two peaks when higher concentration was required. These results suggest that microsaccades are inhibited when attention is concentrated in foveal region, and disinhibited when attention is disengaged. On the other hand, drift eye movements were not influenced by the foveal attention allocation, rather affected by dif-fusing attention to the peripheral visual field, indicating that drift eye movements might be involved in the visual perception.
  • Analysis of eye movements by interviewer and interviewee in interviews, WATANABE Eiji, OZEKI Takashi, KOHAMA Takeshi, Technical report of IEICE. HIP, 114, 226, 1, 6,   2014 09 25 , http://ci.nii.ac.jp/naid/110009950320
    Summary:In interviews, the evaluation by the interviewer is affected by not only the reply by the interviewee but also behaviors (eye and face movements) by interviewees. In this report, we focus on the eye movement by the interviewer and the interviewee. Concretely, the eye movement can be detected by image processing methods for the movie recorded in a mock interview for job hunting. From experimental results, we discuss the relation between the eye movement and the content of the interview by the interviewer and the interviewee.
  • Quantitative measurements of attentional concentration based on analyses of microsaccades and drift eye movements, KOHAMA TAKESHI, KIKKAWA SHO, YOSHIDA HISASHI, 電子情報通信学会技術研究報告, 114, 226(HIP2014 43-59), 87, 92,   2014 09 18 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201402218096220534
  • Analysis of eye movements by interviewer and interviewee in interviews, WATANABE EIJI, OZEKI TAKASHI, KOHAMA TAKESHI, 電子情報通信学会技術研究報告, 114, 226(HIP2014 43-59), 1, 6,   2014 09 18 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201402295261921261
  • A parallel computing method of large-scale simulations for a mathematical model of retinal neuron networks., 西野 誠, 小濱 剛, 吉田 久, 近畿大学生物理工学部紀要 = Memoirs of the Faculty of Biology-Oriented Science and Technology of Kinki University, 34, 35, 46,   2014 09 01 , http://ci.nii.ac.jp/naid/120005735162
    Summary:[要旨] 本研究では, 周辺視野の特性を考慮した網膜数理モデルを対象に, 計算資源の制限の中で計算処理を最大限に効率化することを目的として, 種々の並列計算アルゴリズムを適用し, 富士通製並列計算機PRIMEHPC FX10と汎用のパーソナルコンピュータとの間で計算時間の比較を行った. その結果, 各種の神経細胞層を個別のモジュールとして扱うことで,メッセージ通信によるサイクリック分割とパイプライン通信が実装可能であり,微分方程式の回帰参照の問題が回避できることが示された. また, メッセージ通信が困難な部分にマルチスレッド並列を適用することにより, 効率的な並列処理が実現できた. これらのことから, FX10の性能を最大限に引き出すためには, MPI(Message Passing Interface)を用いたメッセージ通信と, マルチスレッド処理とのハイブリッド並列化が有効であり, これにより高効率で高速な並列計算が可能となることが示された. [Abstract] The purpose of this study is to develop effective methods to compute a mathematical model of the retina which considers peripheral properties of retinal cells in the restriction of computation resources. We compared the machine time with regard to several parallel processing algorithms between the Fujitsu PRIMEHPC FX10 supercomputer system and general personal computers. The results indicate that the implementation of cyclically divided blocks and a pipeline processing with a message passing interface, by dealing with each cell layer as a module, is able to avoid problems of the regression reference of calculation of differential equations. For program codes which are difficult to implement message passing interfaces, we obtained a practical solution by applying multithread processing instead. Furthermore, these results suggest that the performance of the FX10 system is maximized by using a hybrid parallel processing method with message passing interfaces and multithread processing.
  • Embedding of movies in hand-written notes using a wearable camera, WATANABE EIJI, KOIKE KEI, OZEKI TAKASHI, KOHAMA TAKESHI, 映像情報メディア学会技術報告, 38, 33(AIT2014 102-112), 1, 4,   2014 08 18 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201402214266499363
    Summary:In lecturers with writing on the blackboard, the timing of the behaviors (noting and listening) by students plays important roles on the evaluation of the understanding and interest for given contents. In this report, we discuss the embedding of movies in hand-written notes using a wearable camera for the purpose of the analysis of the sequence of behaviors by students. Concretely, we describe image processing methods for the classification of behaviors by students and the detection of the pen position from the movie recorded by a wearable camera. Moreover, we describe a method for the correspondence the movie to the contents in notes based on the time.
  • Digitalization of handwritten contents in handout with a wearable camera, WATANABE Eiji, KOIKE Kei, OZEKI Takashi, KOHAMA Takeshi, IEICE technical report. Life intelligence and office information systems, 114, 150, 17, 21,   2014 07 24 , http://ci.nii.ac.jp/naid/110009945953
    Summary:In lecturers, the handout is an important document for the support of lectures. Moreover, students can effectively understand the lecture by the memorandum in the handout. Furthermore, it is very important for lecturer and students to extract the hand-written memorandum including the writing time in the handout. In this report, we discuss the digitalization of handwritten contents in handout with a wearable camera.
  • Digitalization of handwritten contents in handout with a wearable camera, WATANABE EIJI, KOIKE KEI, OZEKI TAKASHI, KOHAMA TAKESHI, 電子情報通信学会技術研究報告, 114, 150(LOIS2014 11-16), 17, 21,   2014 07 17 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201402296845243172
  • Analysis of behaviors by students in lectures, WATANABE Eiji, OZEKI Takashi, KOHAMA Takeshi, IEICE technical report. Education technology, 113, 482, 177, 182,   2014 03 08 , http://ci.nii.ac.jp/naid/110009862087
    Summary:In this report, we discuss the influence the following three behaviors on the behavior by a specific student in lecturers; (i) the behavior by the lecturer, (ii) the behaviors by other students, and (iii) the behavior by oneself. First, we adopt the following features as behaviors by lecturer and students; (i) the face movement and the head position by lecturer, and face movements by students. Next, the relations among the above features concerning on the behaviors by the lecturer and students can be approximated by multi-layered neural networks. Furthermore, we use a learning method with forgetting for neural networks for the purpose of extraction of rules. Finally, we have analyzed the interaction between behaviors by lecturer and students based on the internal representations.
  • A saliency estimation model for motion images based on receptive field properties of the visual area MST, MORIMOTO Yuzuru, KOHAMA Takeshi, ITE Technical Report, 38, 10, 57, 60,   2014 03 , http://ci.nii.ac.jp/naid/110009807463
    Summary:The purpose of this study is to construct a mathematical model which predicts saliency regions in high-speed egocentric-motion movies by reproducing the properties of the area MST neurons' receptive fields. MST neurons detect global motions such as expansion, contraction, rotation, and so on. Our proposed model is based on a previous model which reproduces center-surround properties of the area MT neurons' receptive fields. MST neurons in the model integrate the responses of the MT neurons by convolving with spacial weight functions of which central portions are biased to particular direction. The simulation results suggest that the modeled MST neurons can detect expansive motions from dynamic random-dot patterns and behave like the effective field of view. The results for the movies which were taken in a running vehicle indicate that the proposed model detects more salient objects around the vanishing point than the previous model. Furthermore, salient regions computed by our model are well similar to our experiential impression of the input movies.
  • A stereo saliency map model considering the disparity energy computation, Konishi Teruki, KOHAMA Takeshi, ITE Technical Report, 38, 10, 53, 56,   2014 03 , http://ci.nii.ac.jp/naid/110009807462
    Summary:Previous saliency-based visual attention models dealt with the mechanism underlying attentional shifts in the early visual system. The data from psychophysical experiments indicate that singletons defined by depth easily pop out, indicating that the saliency of depth information is implicated in visual information processes. However, depth information is not considered in the calculations for saliency maps. In this study, we modified a saliency-based model with regard to using depth information by using the disparity energy computation for calculating the saliency maps for stereo images. Simulation results indicate that proposed model can calculate disparity distribution maps to discriminate objects which pop out in depth. Furthermore, the results for a stereo image input which has multiple depth objects, the proposed model searches each object by referring to the region of shared depth and shift the gaze points from object to object on the basis of depth saliency.
  • Analysis of behaviors by applicants in mock interview, WATANABE Eiji, OZEKI Takashi, KOHAMA Takeshi, ITE Technical Report, 38, 10, 41, 44,   2014 03 , http://ci.nii.ac.jp/naid/110009807459
    Summary:In various interviews, the evaluation by the interviewer is affected by not only the reply by the applicant but also the behavior by the applicant. Moreover, the evaluation by the interviewer is communicated with the applicant and the interaction between the behaviors by the interviewer and the applicant occurs. In this report, we discuss the relation between the evaluation by the interviewer and the behavior by the applicant.
  • Analysis of behaviors by students in lectures, WATANABE EIJI, OZEKI TAKASHI, KOHAMA TAKESHI, 電子情報通信学会技術研究報告, 113, 482(ET2013 92-135), 177, 182,   2014 03 01 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201402267355893691
  • Analysis of behaviors by applicants in mock interview, WATANABE EIJI, OZEKI TAKASHI, KOHAMA TAKESHI, 映像情報メディア学会技術報告, 38, 10(HI2014 28-43/3DIT2014 1-16), 41, 44,   2014 02 25 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201402240944216491
  • A stereo saliency map model considering the disparity energy computation, KONISHI TERUKI, KOHAMA TAKESHI, 映像情報メディア学会技術報告, 38, 10(HI2014 28-43/3DIT2014 1-16), 53, 56,   2014 02 25 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201402251712166090
  • A saliency estimation model for motion images based on receptive field properties of the visual area MST, MORIMOTO YUZURU, KOHAMA TAKESHI, 映像情報メディア学会技術報告, 38, 10(HI2014 28-43/3DIT2014 1-16), 57, 60,   2014 02 25 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201402281189363401
  • A quantitative evaluation of attentional concentration based on drift eye movement analyses, NOGUCHI Daisuke, KOHAMA Takeshi, KIKKAWA Sho, YOSHIDA Hisashi, ITE Technical Report, 38, 10, 45, 48,   2014 02 25 , http://ci.nii.ac.jp/naid/110009807460
    Summary:The purpose of this study is to evaluate the effect of visual attention on the dynamics of drift eye movements objectively. We proposed a signal processing method to separate drift eye movements and microsaccades from fixation eye movements in the experiments which control attentional concentration to the foveal region, and compared the properties of extracted drift eye movements between the conditions of attentional intensities. In our method, microsaccades are detected by using an order-statistic low-pass differentiation filter. The start- and end-point of each microsaccades is discriminated by a discrete pulse transform analysis, then microsaccades are removed from the data. These gaps are filling through the use of an autoregressive model to extract pure drift eye movements. After the extraction of drift eye movements, we analyzed the frequency components and mean-square displacements to examine the fluctuation properties of the drifts. As results, drift eye movements were not influenced by the foveal attention allocation, rather affected by diffusing attention to the peripheral visual field.
  • 8-5 Quantitative evaluation of cognitive loads of voice or manual responses based on eye fixation analyses, NAKAI Yuma, KANOH Yuji, UEDA Shinichi, KURIHARA Masayuki, IWASAKI Kenji, KOHAMA Takeshi, PROCEEDINGS OF THE ITE WINTER ANNUAL CONVENTION, 2014, 0, 8, 5-1_-_8-5-1_,   2014 , http://ci.nii.ac.jp/naid/130005689190
  • 11-14 A saliency estimation model for motion images with visual adaptation property, KODAMA Mitsuhiro, KOHAMA Takeshi, PROCEEDINGS OF THE ITE WINTER ANNUAL CONVENTION, 2014, 0, 11, 14-1_-_11-14-1_,   2014 , http://ci.nii.ac.jp/naid/130005689181
  • 帯域制限された動的ランダムドット観察時の安静時脳活動のNIRS信号解析, NAMIKAWA HIROKI, KOHAMA TAKESHI, YOSHIDA HISASHI, 日本生体医工学会大会プログラム・論文集(CD-ROM), 53rd, 0, ROMBUNNO.O3-10-7, 383-O-384,   2014 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201402227712266372
    Summary:Recent brain science studies have focused on functional connectivity in functional networks. However, experimental conditions are not sufficiently controlled to reduce individual differences in order to make experimental data stable because the definition of resting states is ambiguous. The purpose of this study is to investigate a more stable method of measuring restiong state brain activity. Subjects performed a 2-back task to facilitate activity of the prefrontal cortex temporally. As half-closed eyes help induce a meditative state, we presented low-passed dynamic random-dot patterns (DRD) in the background to make subjects' vision similar to what they would see if their eyes were half-closed. We measured subjects' brain activity with a NIRS device while subjects observed DRDs for 180 seconds. As a result, prefrontal activity decreased earlier as DRDs increased in blurriness. Moreover, brain activity reactivated immediately after reaching the baseline. This suggests that our method may induce stable resting states effectively.
  • 視覚的注意の集中度合いとマイクロサッカード潜時分布の関係, KANO YUJI, KOHAMA TAKESHI, KIKKAWA SHO, YOSHIDA HISASHI, 日本生体医工学会大会プログラム・論文集(CD-ROM), 53rd, 0, ROMBUNNO.O1-05-5, 53-O-54,   2014 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201402247449902537
    Summary:Recent studies have indicated that mechanisms of microsaccades, involuntary small shifts in gaze, are affected by attention. Most studies have shown that mocrosaccade rates increase with a shift of attention, while others have shown that occurrence of mocrosaccades is inhibited when attention is in foveal region. In this study, we calculated latencies of microsaccades and analyzed the relationship between the spatial extent of attention and latencies of microsaccades. Subjects performed rapid serial visual presentation tasks. Targets were defined by differences in luminance contrast from distractors. We controlled focal attention under two conditions: high-contrast (HC) and low-contrast (LC). Results show that the histogram of latencies of microsaccades have two peaks only in the LC. The second peak was delayed approximately 0.3 sec from the peak of the HC. These results suggest that microsaccades are inhibited when attention is concentrated in foveal region, and disinhibited when attention is disengaged.
  • Analysis of behaviors by students in solving for given problems, WATANABE Eiji, OZEKI Takashi, KOHAMA Takeshi, ITE Technical Report, 37, 56, 69, 72,   2013 12 02 , http://ci.nii.ac.jp/naid/110009686767
    Summary:In this report, we consider a learning environment, which students solve the problem while reading contents. Here, we analyze the relationship among the behaviors (reading and writing), the frequency for reading each page and the understanding for contents. Concretely, we analyze the influence the frequency for the objective page and the behaviors for solving on the score for given problems.
  • Analysis of behaviors by speaker and audience in lectures, ITE Technical Report, 37, 55, 41, 44,   2013 12
  • Analysis of behaviors by speaker and audience in lectures, WATANABE Eiji, OZEKI Takashi, KOHAMA Takeshi, ITE Technical Report, 37, 55, 41, 44,   2013 11 29 , http://ci.nii.ac.jp/naid/110009686760
    Summary:In this paper, we discuss the analysis of the interaction between the lecturer and audience in the lecture by using multi-layered neural networks. Here, we adopt the following features as behaviors by lecturer and audience; face and head movement by lecturer, and face movement by audience. The relations among the above features concerning on the behaviors by the lecturer and audience can be approximated by multi-layered neural networks. Furthermore, we use a learning method with forgetting for neural networks for the purpose of extraction of rules. Finally, we have analyzed the interaction between behaviors by lecturer and audience based on the internal representations in multi-layered neural networks for a real lecture.
  • 特徴ベクトルの類似度を考慮した注視履歴の評価指標, YOSHINO HIROKI, KOHAMA TAKESHI, 映像情報メディア学会冬季大会講演予稿集(CD-ROM), 2013, ROMBUNNO.7-2,   2013 11 27 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201402242776612796
  • 2次元空間周波数パターンに対する網膜応答への固視微動の効果, NISHINO MAKOTO, KOHAMA TAKESHI, 映像情報メディア学会冬季大会講演予稿集(CD-ROM), 2013, ROMBUNNO.7-1,   2013 11 27 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201402246589870191
  • 汎用モーションセンサによる反復的運動の自動計数アルゴリズムとデータ管理システムの構築, MAEDA YUTA, NAMIKAWA HIROKI, ONIZUKA MASATOSHI, HASHISHITA NAOYA, MORIMOTO YUZURU, NISHINO MAKOTO, KOHAMA TAKESHI, KUSUMOTO YOSHIKI, ATARASHI YURI, KUSUNOKI MASANOBU, 医療情報学連合大会論文集, 33rd, 974, 975,   2013 11 20 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201402253277751949
  • Analysis of behaviors by students and page transition, WATANABE EIJI, OZEKI TAKASHI, KOHAMA TAKESHI, 電子情報通信学会技術研究報告, 113, 316(ET2013 57-67), 1, 6,   2013 11 15 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201402245182312694
  • Analysis of behaviors by students and page transition, WATANABE Eiji, OZEKI Takashi, KOHAMA Takeshi, IEICE technical report. Education technology, 113, 316, 1, 6,   2013 11 15 , http://ci.nii.ac.jp/naid/110009889300
    Summary:In this report, we consider a learning environment, which students solve the problem while reading contents. Here, we analyze the relationship among the behaviors (reading and writing), the frequency for reading each page and the understanding for contents. Concretely, we analyze the influence the frequency for the objective page and the behaviors on the score for given problems.
  • Digitalization of handwritten notes using a wearable camera, WATANABE Eiji, OZEKI Takashi, KOHAMA Takeshi, 電気学会研究会資料. CMN, 通信研究会, 2013, 25, 19, 23,   2013 09 12 , http://ci.nii.ac.jp/naid/10031200595
  • Digitization of handwritten notes using a wearable camera, WATANABE Eiji, OZEKI Takashi, KOHAMA Takeshi, IEICE technical report. Image engineering, 113, 211, 19, 23,   2013 09 12 , http://ci.nii.ac.jp/naid/110009817850
    Summary:In taking hand-written memorandum, the taking process plays often important roles for recalling related information in addition of notations (words and figures) in the memorandum. In this report, we discuss image processing methods for the reproduction of the process through taking hand-written memorandum from the movie recorded by a wearable camera.
  • Digitalization of handwritten notes using a wearable camera, WATANABE EIJI, OZEKI TAKASHI, KOHAMA TAKESHI, 電子情報通信学会技術研究報告, 113, 210(LOIS2013 10-24), 19, 23,   2013 09 05 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201302216080545549
  • Digitalization of handwritten notes using a wearable camera, WATANABE Eiji, OZEKI Takashi, KOHAMA Takeshi, 電子情報通信学会技術研究報告. EMM, マルチメディア情報ハイディング・エンリッチメント, 113, 212, 19, 23,   2013 09 05 , http://ci.nii.ac.jp/naid/110009783184
    Summary:In taking hand-written memorandum, the taking process plays often important roles for recalling related information in addition of notations (words and figures) in the memorandum. In this report, we discuss image processing methods for the reproduction of the process through taking hand-written memorandum from the movie recorded by a wearable camera.
  • Digitalization of handwritten notes using a wearable camera, WATANABE Eiji, OZEKI Takashi, KOHAMA Takeshi, IEICE technical report. Life intelligence and office information systems, 113, 210, 19, 23,   2013 09 05 , http://ci.nii.ac.jp/naid/110009784515
    Summary:In taking hand-written memorandum, the taking process plays often important roles for recalling related information in addition of notations (words and figures) in the memorandum. In this report, we discuss image processing methods for the reproduction of the process through taking hand-written memorandum from the movie recorded by a wearable camera.
  • Digitization of handwritten notes using a wearable camera, 渡邊 栄治, 尾関 孝史, 小濱 剛, 映像情報メディア学会技術報告 = ITE technical report, 37, 38, 19, 23,   2013 09 , http://ci.nii.ac.jp/naid/40019885528
  • Analysis of behaviors by speaker and audience by using time series model, WATANABE Eiji, OZEKI Takashi, KOHAMA Takeshi, ITE Technical Report, 37, 35, 59, 62,   2013 07 25 , http://ci.nii.ac.jp/naid/110009660676
    Summary:In this report, the dominant behaviors of the speaker and audience in the lecture are analyzed by using the time-series model. First, we detect as a feature for behavior the number of skin-colored pixels in face region of the speaker and audience. Next, we construct time series models for these features for the speaker and audience. Furthermore, we analyze the synchronization phenomena in the speaker and audience by comparing time series models.
  • A study on the relationship between page transition and understanding for contents, WATANABE EIJI, OZEKI TAKASHI, KOHAMA TAKESHI, 電子情報通信学会技術研究報告, 112, 500(ET2012 82-117), 43, 48,   2013 03 22 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201302269182945971
  • A study on the relationship between page transition and understanding for contents, WATANABE Eiji, OZEKI Takashi, KOHAMA Takeshi, IEICE technical report. Education technology, 112, 500, 43, 48,   2013 03 22 , http://ci.nii.ac.jp/naid/110009713187
    Summary:In this report, we consider a learning environment, which students solve the problem while reading contents. Here, we analyze the relationship between the frequency for reading each page and the understanding for contents. The above relationship can be modeled by neural networks. Furthermore, we use a learning method with forgetting for neural networks for the purpose of extraction of rules. Finally, we have analyzed the relationship between the frequency for each page and the understanding for contents by using the internal representations of multi-layered neural networks.
  • Analysis of face direction by participants in Indian-poker game (Part 2), Technical Report of IEICE HCS, 112, 455, 167, 171,   2013 03
  • Continuous inhibition of microsaccades in attentional concentration, ITE Technical Report, 37, 12, 51, 54,   2013 03
  • A saliency map model for dynamic images based on receptive field properties of visual area MT, ITE Technical Report, 37, 12, 39, 42,   2013 03
  • A visual search model based on the spatio-temporal properties of visual attention in different feature domains, ITE Technical Report, 37, 12, 35, 38,   2013 03
  • A model for predicting gaze shifts considering scanned log of gazed positions, ITE Technical Report, 37, 12, 31, 34,   2013 03
  • A mathematical model of working memory system in higher order visual processing, ITE Technical Report, 37, 12, 27, 30,   2013 03
  • A saliency map model for dynamic images based on receptive field properties of visual area MT, TSUDA KODAI, KOHAMA TAKESHI, 映像情報メディア学会技術報告, 37, 12(HI2013 41-56/3DIT2013 9-24), 39, 42,   2013 02 26 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201302214001169801
    Summary:Saliency map models are mathematical expressions of the characteristics of bottom-up attention processing (Itti & Koch, 2000). The saliency maps are calculated by weighting to the distribution of color and the orientation of input images on the bases of the physiological knowledge of early visual system. In late years, saliency-based models were modified to predict gaze positions for moving objects. However, these models have not been taken into the neural response characteristics of motion detection area in the brain, such as the area MT. The purpose of this study is to calculate the saliency maps for the motion components in moving images by reproducing the properties of the area MT neurons' receptive fields involved in motion perception. To evaluate the performance of proposed model, we conducted simulation experiments for the motion pop-out stimulus. The simulation results suggest that the proposed model can pick up the pop-out region more sensitively than the previous model. Furthermore, the simulation results for the movies of natural scenery, our model persistently responds to the region in which certain motion contrasts are contained whereas the previous model responds intermittently.
  • Continuous inhibition of microsaccades in attentional concentration, ENDO SHO, KOHAMA TAKESHI, NOGUCHI DAISUKE, 映像情報メディア学会技術報告, 37, 12(HI2013 41-56/3DIT2013 9-24), 51, 54,   2013 02 26 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201302257714695156
    Summary:Recent studies show that the mechanism responsible for the occurrence of microsaccades, which are small involuntary shifts in the eye-gaze position, is related to the visual attention system. These studies report that the microsaccade rate increases with shift of attention allocation. In contrast, other studies show that the occurrence of microsaccades is inhibited when visual attention is intensely applied on a fixed target. It has not yet been established as to which of these conclusions is correct. In this study, we hypothesized that microsaccade rate decreases with the degree of attentional concentration. Subjects performed RSVP tasks with instructions to maintain their fixation on the alphabet characters which were displayed on the center of a CRT monitor. The degree of attention engagement of the subjects was controlled by changing the contrast of target characters. Then we analyzed the relationship between the microsaccade rate and the degree of attention engagement. The results show that the microsaccade rate was suppressed from just before the target objects were displayed, and increased after the target was extinguished. When higher concentration was required, this inhibition of microsaccade occurrence was prolonged. These results suggest that the microsaccade rate is inhibited with the concentration of visual attention in the foveal region.
  • A mathematical model of working memory system in higher order visual processing, NISHIDA NAOKI, KOHAMA TAKESHI, 映像情報メディア学会技術報告, 37, 12(HI2013 41-56/3DIT2013 9-24), 27, 30,   2013 02 26 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201302263852616356
    Summary:The purpose of this study is to understand the function of working memories while seeking a target during visual search tasks by using a neuron network model. A previous study indicated that the model which can reproduce gaze shifts while searching a target must contain a mechanism with which allocating attention to the visual attributes dynamically shifts (Sugimoto & Kohama, 2011) and maintaining inhibition to a past gazed position for several steps. However, the target information must set as a parameter before initiation of searching tasks, and also implementation of the inhibition of return in this model was not based on the physiological evidence. In this study, we proposed a modified version of Sugimoto & Kohama's model with considering the working memories for the visual attributes derived by PF and IT network. Furthermore, we added a network which assumed TPJ between V4 and LIP to memorize the locus of past gazed regions for the use of the inhibition of return. The visual search simulation results suggest that the target detection rate of our model, without giving any target information, is significantly higher than that of the previous model.
  • A model for predicting gaze shifts considering scanned log of gazed positions, YAMASAKI MAYO, KOHAMA TAKESHI, 映像情報メディア学会技術報告, 37, 12(HI2013 41-56/3DIT2013 9-24), 31, 34,   2013 02 26 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201302273718183112
    Summary:In late years, the distribution of gaze on the media, such as Web contents, are applied to evaluate the attractiveness of users attention. Mathematical models which computes the most likely target location based on the saliency maps is frequently used to predict gaze shifts in the visual scenery. However, these models can not reproduce temporal transition of gaze positions; the history of scanned regions. The purpose of this study is to predict the gaze shifts with temporal transition in the visual search tasks. Our model reproduces gaze shifts for searching targets by using conditional probability considering scanned logs of gaze positions. The probability map is calculated from the saliency distribution. To test the performances of our model, we compared the efficiency of target detection between our model and Itti & Koch's original model in some visual search simulations. The results show that the proposed model can shift gaze positions without applying a winner-take-all process which is needed for the original model to select gaze targets. Moreover, the proposed model improves the accuracy of target detection rate, and also it can detect targets in the fewer steps than the original model. We computed the averaged diffusivity and similarity for the use of the indexes to evaluate the scan path profile of simulated gazed positions. These indexes indicate that the gaze distributions produced by the proposed model contain the temporal transition of scanned logs of the gazed positions.
  • A visual search model based on the spatio-temporal properties of visual attention in different feature domains, YANO KATSUYA, KOHAMA TAKESHI, 映像情報メディア学会技術報告, 37, 12(HI2013 41-56/3DIT2013 9-24), 35, 38,   2013 02 26 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201302295180789248
    Summary:Previous saliency-based visual attention models dealt with the mechanism underlying attentional shifts in the early visual system. Such models can predict the distribution of gaze movements on the basis of saliency maps (Itti&Koch, 2000). Saliency maps are calculated by weighting to the distribution of color and the orientation of input images. Since predicted gaze positions using the previous saliency map models are deterministically selected by tracing the peaks of saliency distribution, the simulated trajectories of gaze positions show non-contextual and unnatural patterns. In this study, we purposed a mathematical model to reproduce more realistic gaze distributions. We have carried out an extension of the saliency map taking into account the spatio-temporal characteristics of attention for the visual attributes, and also image projection from retina to V1; cortical magnification factor. To evaluate the performance of our model, we conducted visual search task simulations. The results indicate that the target detection rate of our model are higher than that of Itti & Koch's model and simulated gaze distributions show contextual patterns while searching for the target.
  • Analysis of face direction by participants in Indian-poker game (Part 2), WATANABE EIJI, OZEKI TAKASHI, KOHAMA TAKESHI, 電子情報通信学会技術研究報告, 112, 455(HCS2012 76-110), 167, 171,   2013 02 25 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201302220870803570
  • Analysis of face direction by participants in Indian-poker game (Part 2), WATANABE Eiji, OZEKI Takashi, KOHAMA Takeshi, Technical report of IEICE. HCS, 112, 455, 167, 171,   2013 02 25 , http://ci.nii.ac.jp/naid/110009703350
    Summary:In this report, we discuss the analysis of the interaction among the participants in the Indian-poker game. In this game, the participant can see other participants' cards and the participant can not see ones own card. Therefore, the participants compare other participants' cards and turn their eyes. Here, we propose an image processing methods which can detect the face direction from moving images through an USB camera. Finally, we show results for the analysis of the participants' behaviors based on detected face direction. Here, we divide the process for the final decision into the processes for the estimation of own card and the match. Especially, we focus on the diflFerence between the change of face direction by each participant in the above two processes.
  • 7-2 An evaluation index of fixation scan paths based on the similarity of feature vectors, YOSHINO Hiroki, KOHAMA Takeshi, PROCEEDINGS OF THE ITE WINTER ANNUAL CONVENTION, 2013, 0, 7, 2,   2013 , http://ci.nii.ac.jp/naid/110009725986
    Summary:The saliency based mathematical models are frequently used to predict observer's gaze shifts. However, evaluation methods of scan path for several gaze steps do not exist. In this study, we proposed a new index by which the similarity of feature vectors on the passed gazed locations were veraged. The results suggest that our index is effective to compare the similarity of simulated scan path and human eye movements.
  • 7-1 The effects of fixation eye movements on retinal responses for two dimensional spatial frequency patterns, NISHINO Makoto, KOHAMA Takeshi, PROCEEDINGS OF THE ITE WINTER ANNUAL CONVENTION, 2013, 0, 7, 1,   2013 , http://ci.nii.ac.jp/naid/110009725985
    Summary:In this study, we propose a mathematical model of the retinal network considering the characteristics of peripheral vision to evaluate the influence of fixation eye movements on the visual perception. Simulation results show that microsaccades enhance the responses of M-type ganglion cells for a vertically sinusoidal gratings, but maintain their resting state for a random dot pattern which consists of a particular spacial frequency.
  • MT野の受容野特性を考慮した動画像に対する顕著性マップの算出, TSUDA KODAI, KOHAMA TAKESHI, 映像情報メディア学会冬季大会講演予稿集(CD-ROM), 2012, ROMBUNNO.9-12,   2012 11 27 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201202204396802041
  • 覚醒水準変動の客観的評価のためのSEM検出手法, HONDA SHOGO, KOHAMA TAKESHI, YOSHIDA HISASHI, 映像情報メディア学会冬季大会講演予稿集(CD-ROM), 2012, ROMBUNNO.9-8,   2012 11 27 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201202256847714303
  • 視覚的注意機構の数理モデルによる視覚探索のシミュレーション, KOHAMA TAKESHI, 自動制御連合講演会(CD-ROM), 55th, ROMBUNNO.1E101,   2012 11 17 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201202249080348342
  • 固視微動と心拍変動の解析に基づく映像酔いをもたらす映像要素の定量的分析, 小濱剛, 吉田久, 北林勇弥, 兵藤宏紀, Mem Fac Biol Oriented Sci Technol Kinki Univ, 30, 1, 15,   2012 09 30 , http://jglobal.jst.go.jp/public/201202246034986475
  • 〈Original Papers〉A quantitative evaluation of visual factors of cybersickness by analyzing fixation eye movements and heart rate variability, 小濱 剛, 吉田 久, 北林 勇弥, 兵藤 宏紀, Memoirs of the Faculty of Biology-Oriented Science and Technology of Kinki University = 近畿大学 生物理工学部 紀要, 30, 1, 15,   2012 09 01 , http://ci.nii.ac.jp/naid/120005735140
    Summary:[要旨]手振れのような振動や回転を含んだ映像は, 吐気や目眩などの乗り物酔いと同様の症状を引き起こす. この症状を映像酔いと呼ぶ. 本研究では, 映像酔を誘発する映像要素を特定することを目的として, 特定の運動成分からなる映像を観察中の主観的な酔いの程度と固視微動および心拍変動の解析を行った. 映像が水平方向に移動するパン, 回転方向に変移するロール, 拡大と縮小により生じるズームの3種の映像要素により構成される運動するランダムドットパターン(ダイナミックランダムドット)を観察中に計測された固視微動データに対して周波数解析を行った結果, 実験の進行に伴って徐々に視線の揺らぎが増し, 注視の維持が困難になることが示された. また, パンまたはロール成分のみからなる動画を観察する際の心拍変動を解析した結果, パン成分のみの映像の方が, 心拍変動のHRV(HF/LF)が低い値となることが明らかとなり, パン成分が交感神経の亢進をもたらすことが示唆された. これらの結果から, 水平方向の運動成分を持った映像を長時間視聴することによって生じる視覚系と前庭系および体性感覚系との矛盾の蓄積が, 映像酔いをもたらしているものと推察され, 固視微動や心拍変動から酔いの進行の定量化が可能であることが示された. [Abstract] Videos with camera shake containing strong vibrational or rotational motion may cause some symptoms similar to motion sickness such as nausea, dizziness and headache. It is called cybersickness, or visually induced motion sickness. In this paper, we have evaluated cybersickness by analyzing fixation eye movements and heart rate variability of subjects viewing videos of which content was restricted to certain visual factors in order to identify the effective motion component for cybersickness. Firstly, fixation eye movements while subjects were watching random dots which consist of each of three visual factors, such as Pan, Roll and Zoom were measured and evaluated by spectral analysis. The results show that variability of the eye movements is increased as the experiment session progresses and it suggests that it is difficult to maintain the attention of fixation as cybersickness progresses. Secondly, we have evaluated the heart rate variability while subjects were watching the motion pictures which are not random dots but well-controlled motion pictures of an indoor scene and an out outdoor scene. Spectral analysis of the heart rate variability demonstrates that HF/LF measure in the Pan condition has lower values than in the Roll condition and it suggests that Pan motion in the video increases sympathetic nerve activity. These results indicate that cybersickness is caused by cumulative inconsistencies among visual, vestibular, and somatosensory systems for a long time while watching videos. Also, we have shown that progression of sickness can be quantified by analyzing fixation eye movements and heart rate variability.本研究は近畿大学生物理工学部戦略的研究No.07-I-02, 2007の助成を受けた.
  • Noise reduction for images by ensemble learning, WATANABE EIJI, OZEKI TAKASHI, KOHAMA TAKESHI, 電子情報通信学会技術研究報告, 112, 168(NC2012 13-35), 13, 18,   2012 07 23 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201202258011621982
    Summary:This report discusses a restoration method for JPEG images based on ensemble learning algorithm for multiple multi-layered neural networks. When images have edge and non-edge regions, it is difficult for single filter having fixed coefficients to reduce both blocky and mosquito noises adequately. Here, new restoration methods for JPEG images are proposed by introducing multiple muliti-layered neural networks. Each neural network can be adapted for edge, flat, and texture regions in images by ensemble learning. From experimental results, the proposed method can obtain good restoration accuracy compared with conventional filters. Moreover, we have confirmed that the proposed method could automatically assign restoration tasks to each neural network according to the characteristics of each region in given distorted images.
  • 網膜数理モデルに基づく固視微動の視知覚増強効果, KOHAMA TAKESHI, FUKUOKA TAKUYA, システム制御情報学会研究発表講演会講演論文集(CD-ROM), 56th, ROMBUNNO.M14-3,   2012 05 21 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201202230218667115
  • 視覚的注意の集中がもたらすマイクロサッカードの抑制効果, ENDO SHO, KOHAMA TAKESHI, Mem Fac Biol Oriented Sci Technol Kinki Univ, 29, 7, 15,   2012 03 31 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201202254042203679
  • 〈Original Papers〉Inhibition of microsaccade rate caused by focus of visual attention, 遠藤 翔, 小濱 剛, Memoirs of the Faculty of Biology-Oriented Science and Technology of Kinki University = 近畿大学 生物理工学部 紀要, 29, 7, 15,   2012 03 01 , http://ci.nii.ac.jp/naid/120005735137
    Summary:[要旨] 注視時に不随意に発生するマイクロサッカードの発生機序と, 視覚的注意機構との関与を示す報告が相次いでいる. 先行研究の多くは, 注意の移動に伴ってマイクロサッカード発生頻度が増加することを指摘しているが, 一方では, 注意の集中によってマイクロサッカード発生頻度が低下する可能性を示唆する報告もあり, いずれの見解が妥当であるのか結論は得られていない. そこで本研究では, 注意の集中によりマイクロサッカードの発生頻度が減少することを仮定し, 注視を維持した状態で注意の集中度を制御する実験を行い, このときのマイクロサッカードの発生頻度について解析を行った. 実験課題は, モニタ中央に連続的に表示される英字を妨害刺激とし, ランダムなタイミングで表示される明るさの異なる英字を目標刺激として読み取るものであり, 輝度コントラストが高い場合をHigh Contrast 条件 (HC), 低い場合をLow Contrast 条件(LC), 文字の読み取りを課さない場合をControl条件とした. これら3つの条件で注意の集中度をコントロールし, このときの眼球運動を計測してマイクロサッカード発生頻度の解析を行った. 注意の集中度合いを検証するため, 文字の読み取りと同時に, 周辺視野に配置した低い空間周波数のガボールパッチを一定速度で左右いずれかに回転運動させ, 回転方向の検出を課した. 実験の結果, LC条件においてマイクロサッカードの発生が抑制される傾向が示され, ガボールパッチの検出率から, この条件において注意がより集中されていたことが確認された. このことから, 注意の集中によりマイクロサッカードが抑制されることが示唆された. [Abstract] Recent studies show that the mechanism responsible for the occurrence of microsaccades, which are small involuntary shifts in the eye-gaze position, is related to the visual attention system. Some of these studies show that the microsaccade rate increases with attention shift. In contrast, the other studies indicate that the occurrence of microsaccades is inhibited when visual attention is focused around a fixed target. It has not yet been established as to which of these conclusions is correct. In this study, we hypothesized that the microsaccade rate decreases with focal attention and carried out experiments to control the focus of subjects' attention when they were maintaining their fixation. Using a rapid serial visual presentation (RSVP) paradigm, we displayed alphabets at the center of a CRT display. Subjects were instructed to detect randomly displayed blackish letters from among the gray letters on the screen. The contrast between the target and distractor letters was adjusted to either high contrast (HC task) or low contrast (LC task) in order to control the degree of focal attention. As a control, no target letters were displayed (Control task). While subjects were pursuing these tasks, their fixation eye movements were measured. To verify the degree of focal attention, we tested the subjects on a rotation direction detection task; this task involved the detection of a low-spatial-frequency Gabor patch that rotated clockwise or counterclockwise at a uniform speed in the subject's peripheral vision. The results indicate that microsaccade rate was more inhibited in the LC tasks. The results of the Gabor-patch rotation detection show that the subjects' visual attention was more intense around the fovea in the LC tasks than in the HC tasks. These results suggest that the microsaccade rate varies with the degree of focal attention around the foveal region.
  • Discrimination between reading and writing behaviors and analysis for transition of page number, WATANABE EIJI, OZEKI TAKASHI, KOHAMA TAKESHI, 電子情報通信学会技術研究報告, 111, 470(LOIS2011 73-114), 43, 48,   2012 03 01 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201202201496683890
    Summary:In this report, we discuss the change of page number and image processing methods for discrimination between behaviors in reading contents and taking notes for contents on the display. First, scene images for contents can be recorded by a sunglasses-type camera. Next, a few features can be extracted based on color information from these images and the discrimination procedure can be executed by the discrimination analysis and the classification method by using multi-layered neural networks. Finally, we evaluate the discrimination precision and discuss the relations among page transition, behaviors by students and their notes.
  • 〈Original Papers〉Inhibition of microsaccade rate caused by focus of visual attention, 遠藤 翔, 小濱 剛, Memoirs of the Faculty of Biology-Oriented Science and Technology of Kinki University, 29, 7, 15,   2012 03 , http://ci.nii.ac.jp/naid/120004009247
    Summary:[要旨] 注視時に不随意に発生するマイクロサッカードの発生機序と, 視覚的注意機構との関与を示す報告が相次いでいる. 先行研究の多くは, 注意の移動に伴ってマイクロサッカード発生頻度が増加することを指摘しているが, 一方では, 注意の集中によってマイクロサッカード発生頻度が低下する可能性を示唆する報告もあり, いずれの見解が妥当であるのか結論は得られていない. そこで本研究では, 注意の集中によりマイクロサッカードの発生頻度が減少することを仮定し, 注視を維持した状態で注意の集中度を制御する実験を行い, このときのマイクロサッカードの発生頻度について解析を行った. 実験課題は, モニタ中央に連続的に表示される英字を妨害刺激とし, ランダムなタイミングで表示される明るさの異なる英字を目標刺激として読み取るものであり, 輝度コントラストが高い場合をHigh Contrast 条件 (HC), 低い場合をLow Contrast 条件(LC), 文字の読み取りを課さない場合をControl条件とした. これら3つの条件で注意の集中度をコントロールし, このときの眼球運動を計測してマイクロサッカード発生頻度の解析を行った. 注意の集中度合いを検証するため, 文字の読み取りと同時に, 周辺視野に配置した低い空間周波数のガボールパッチを一定速度で左右いずれかに回転運動させ, 回転方向の検出を課した. 実験の結果, LC条件においてマイクロサッカードの発生が抑制される傾向が示され, ガボールパッチの検出率から, この条件において注意がより集中されていたことが確認された. このことから, 注意の集中によりマイクロサッカードが抑制されることが示唆された. [Abstract] Recent studies show that the mechanism responsible for the occurrence of microsaccades, which are small involuntary shifts in the eye-gaze position, is related to the visual attention system. Some of these studies show that the microsaccade rate increases with attention shift. In contrast, the other studies indicate that the occurrence of microsaccades is inhibited when visual attention is focused around a fixed target. It has not yet been established as to which of these conclusions is correct. In this study, we hypothesized that the microsaccade rate decreases with focal attention and carried out experiments to control the focus of subjects' attention when they were maintaining their fixation. Using a rapid serial visual presentation (RSVP) paradigm, we displayed alphabets at the center of a CRT display. Subjects were instructed to detect randomly displayed blackish letters from among the gray letters on the screen. The contrast between the target and distractor letters was adjusted to either high contrast (HC task) or low contrast (LC task) in order to control the degree of focal attention. As a control, no target letters were displayed (Control task). While subjects were pursuing these tasks, their fixation eye movements were measured. To verify the degree of focal attention, we tested the subjects on a rotation direction detection task; this task involved the detection of a low-spatial-frequency Gabor patch that rotated clockwise or counterclockwise at a uniform speed in the subject's peripheral vision. The results indicate that microsaccade rate was more inhibited in the LC tasks. The results of the Gabor-patch rotation detection show that the subjects' visual attention was more intense around the fovea in the LC tasks than in the HC tasks. These results suggest that the microsaccade rate varies with the degree of focal attention around the foveal region.
  • Simulation analysis of enhancement of visual perception caused by fixation eye movements based on a mathematical model of retina, ITE Technical Report HI, 36, 13, 55, 58,   2012 03
  • Arousal evaluation based on the analysis of microsaccade rate and pupil fluctuation, ITE Technical Report HI, 36, 13, 51, 54,   2012 03
  • Quantitative assessment of visually induced motion sickness based on the analysis of fixation eye movements, ITE Technical Report HI, 36, 13, 47, 50,   2012 03
  • Analysis of interaction between speaker and audience in lectures, Technical Report of IEICE HCS, 111, 464, 89, 84,   2012 03
  • Analysis of face direction by participants in Indian-poker game, Technical Report of IEICE HCS, 111, 464, 85, 88,   2012 03
  • 銚子市内におけるゲンジボタル生息域と水質に関する研究, KOHAMA TAKESHI, HAYASHI MIYUKI, 千葉科学大学紀要, 5, 29, 34,   2012 02 28 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201202204339986624
  • Simulation analysis of enhancement of visual perception caused by fixation eye movements based on a mathematical model of retina, FUKUOKA TAKUYA, KOHAMA TAKESHI, 映像情報メディア学会技術報告, 36, 13(HI2012 47-62/3DIT2012 16-31), 55, 58,   2012 02 28 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201202211720305915
    Summary:In this study, we performed a simulation experiments using a mathematical model of retina considering peripheral characteristics to evaluate the influence of fixation eye movements. Recent studies indicate that drifts and tremor enhance particular spacial frequency components, and microsaccades emphasize the difference of contrast on the visual stimuli. However, the influence of fixation eye movements on the retina, especially on the peripheral retina, is not elucidated. The proposed model considers the distribution function of cone cells and reproduces the property of increase in the size of peripheral receptive fields of ganglion cells. The simulation results show that drifts and tremor enhance the response of ganglion cells for high spatial frequency input, and microsaccades enhance the response for low spatial frequency inputs. These trends are more prominent for in the M-type ganglion cells at some distance from fovea. Furthermore, it suggests that fixation eye movements might derive a synchronous fluctuation on the response of ganglion cells.
  • Quantitative assessment of visually induced motion sickness based on the analysis of fixation eye movements, NAKAGAWA KEI, KOHAMA TAKESHI, YOSHIDA HISASHI, KIKKAWA SHO, 映像情報メディア学会技術報告, 36, 13(HI2012 47-62/3DIT2012 16-31), 47, 50,   2012 02 28 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201202292665908958
    Summary:In this study, we analyzed fixation eye movements immediately after watching certain length of movie contents which contain some factors to induce motion sickness. Motion sickness is defined as nausea, dizziness, vomiting and related symptoms caused by repetitive viewing of highly tremble movies. This symptom is caused by visual exposure; however, there is no evidence that motion sickness affects the dynamics of fixation eye movements. We apply a microsaccade rate analysis, a fluctuation energy analysis, and a random walk analysis to fixation eye movements for the purpose of evaluate the effects of motion sickness on the behavior of subjects objectively. The results show that the microsaccade rate and the fluctuation energy defined by root mean square of eye movements increase, and the dispersion of two-dimensional fixation paths varies widely in connection with deterioration of the symptoms. These results suggest that fixation eye movements could be a quantitative measure of motion sickness.
  • Arousal evaluation based on the analysis of microsaccade rate and pupil fluctuation, TANAKA TATSURO, KOHAMA TAKESHI, YOSHIDA HISASHI, 映像情報メディア学会技術報告, 36, 13(HI2012 47-62/3DIT2012 16-31), 51, 54,   2012 02 28 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201202298347794356
    Summary:It is well known that decline of arousal level causes of poor performance of movements or judgments, while doing VDT work, driving cars, and so on, and also reduces productivity and safety. Previous studies show the slow eye movements (SEM) could be a candidate for an indicator of decline of arousal. However, since SEMs appear just prior to sleep onset, it is not sufficient to evaluate transition of arousal states. In this study, we examine the effects of the transition of arousal on microsaccade rate and pupil fluctuation while subjects are continuously gazing a fixation crosshair. The subjects are instructed to indicate by mouse-licks when they are aware of having slept. The eye movement and pupil fluctuation data are analyzed for the former period from SEMs, which are detected immediately before the mouse-clicks. The results show that longitudinal miosis of pupil diameter and gradual rise of microsaccade rate are observed in advance of the occurrence of SEMs. These resu Its suggest that the arousal level could be evaluated by monitoring eye movements and pupil fluctuations.
  • Analysis of interaction between speaker and audience in lectures, WATANABE EIJI, OZEKI TAKASHI, KOHAMA TAKESHI, 電子情報通信学会技術研究報告, 111, 464(HCS2011 65-87), 89, 94,   2012 02 27 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201202223571011197
    Summary:In this paper, we discuss the analysis of the interaction between the speaker and audience in the lecture by using multi-layered neural networks. Here, we adopt the following features as behaviors by speaker and audience; the loudness of speech by speaker, face and hand movements by speaker, face movements by audience. The relations among the above features concerning on the behaviors by the speaker and audience can be approximated by multi-layered neural networks. Furthermore, we use a learning method with forgetting for neural networks for the purpose of extraction of rules. Finally, we have analyzed the interaction between behaviors by speaker and audience based on the internal representations in multi-layered neural networks for a real lecture.
  • Analysis of face direction by participants in Indian-poker game, WATANABE EIJI, OZEKI TAKASHI, KOHAMA TAKESHI, 電子情報通信学会技術研究報告, 111, 464(HCS2011 65-87), 85, 88,   2012 02 27 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201202244675361030
    Summary:In this report, we discuss the analysis of the interaction among the participants in the Indian-poker game. In this game, the participant can see other participants' cards and the participant can not see ones own card. Therefore, the participants compare other participants' cards and turn their eyes. Here, we propose an image processing methods which can detect the face direction from moving images through an USB camera. Finally, we show results for the analysis of the participants' behaviors based on detected face direction.
  • 9-8 A slow eye movement (SEM) detection method for objective evaluations of arousal fluctuations, HONDA Shougo, KOHAMA Takeshi, YOSHIDA Hisashi, PROCEEDINGS OF THE ITE WINTER ANNUAL CONVENTION, 2012, 0, 9, 8-1,   2012 , http://ci.nii.ac.jp/naid/110009669676
    Summary:Recent studies indicate that microsaccades increase before occurrence of slow eye movements (SEM). However, their SEM detection methods were not perfection. In this study, we proposed a new SEM detection technique based on the SEM detector for EOG data. The results suggest that our method can pick up the start and end points of SEM periods precisely.
  • 9-12 A saliency map computation for dynamic images based on the receptive field properties of visual area MT, TSUDA Kodai, KOHAMA Takeshi, PROCEEDINGS OF THE ITE WINTER ANNUAL CONVENTION, 2012, 0, 9, 12-1,   2012 , http://ci.nii.ac.jp/naid/110009669680
    Summary:In this study, we propose a receptive field model of visual area MT, which relates with motion perception, to compute saliency maps of motion components in dynamic images. The proposed model can reproduce center-surrounding feature of the responses of MT neurons. The results show that the responses of the model enhance in the region of higher motion contrasts.
  • 離散パルス変換解析(DPT)によるマイクロサッカードの検出, NOGUCHI DAISUKE, KIKKAWA SHO, KOHAMA TAKESHI, YOSHIDA HISASHI, 日本生体医工学会大会プログラム・論文集(CD-ROM), 51st, ROMBUNNO.O1-10-7,   2012 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201202247154842171
  • 12-2 Microsaccade detection with a order-statistic low-pass differentiation filter, NOGUCHI Daisuke, KOHAMA Takeshi, KIKKAWA Sho, YOSHIDA Hisashi, ITE Winter Annual Convention, 2011, 2011, 12, 2-1,   2011 12 21 , http://ci.nii.ac.jp/naid/110009598325
    Summary:In this study, we propose a new method to detect microsaccades using a order-statistic low-pass differentiation filter.The usual method need to trial and error processes to decide the threshold value. Our method can detect microsaccades over 90%accuracy by applying a dynamic threshold technique without any parameter tuning separately for each data.
  • 12-3 A simulation analysis of the effects of miniature eye movements on retinal responses, FUKUOKA Takuya, KOHAMA Takeshi, ITE Winter Annual Convention, 2011, 2011, 12, 3-1,   2011 12 21 , http://ci.nii.ac.jp/naid/110009598326
    Summary:This study proposes a mathematical model of retinal ganglion cells considering peripheral characteristics to evaluate the influence of miniature eye movements. Simulation results show that microsaccades enhance the response of M type ganglion cells at some distance from central fovea. This indicate that microsaccades play important roles in peripheral perception.
  • 固視微動が網膜像に及ぼす影響のシミューレーション解析, FUKUOKA TAKUYA, KOHAMA TAKESHI, 映像情報メディア学会冬季大会講演予稿集(CD-ROM), 2011, ROMBUNNO.12-3,   2011 11 30 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201102230272364430
  • 順序統計低域微分フィルタを用いたマイクロサッカードの検出, NOGUCHI DAISUKE, KOHAMA TAKESHI, KIKKAWA SHO, YOSHIDA HISASHI, 映像情報メディア学会冬季大会講演予稿集(CD-ROM), 2011, ROMBUNNO.12-2,   2011 11 30 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201102255225147866
  • 視覚属性に対する注意の影響と網膜像の皮質における写像を考慮した視覚探索モデル, YANO KATSUYA, KOHAMA TAKESHI, Mem Fac Biol Oriented Sci Technol Kinki Univ, 28, 41, 52,   2011 09 30 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201102288067199840
  • 〈Original Papers〉Visual search model considering spatial modification of visual attributes and cortical magnification of retinal images., 矢野 勝也, 小濱 剛, Memoirs of the Faculty of Biology-Oriented Science and Technology of Kinki University = 近畿大学 生物理工学部 紀要, 28, 41, 52,   2011 09 01 , http://ci.nii.ac.jp/naid/120005735132
    Summary:[要旨] 初期視覚神経系の情報処理の特徴を定式化した顕著性マップモデルは, 顕著さの勾配に従って走査することで視線の移動を再現することができるが, 特定の候補点の中から視線の移動先が選出されるために, ある程度長時間のシミュレーションでは循環が生じてしまう. 本研究では, 同じ視対象を繰り返し注視することを防ぐ復帰抑制と, 周辺視野において生じる目標対象と同じ属性への応答を強化させる復帰増強と呼ばれる現象に着目し, 従来の顕著性マップモデルに対して, これらの緒特性についての拡張を行った. さらに, 網膜上の錐体細胞の密度分布に起因する第1次視覚野における皮質拡大を考慮し, 視線移動のたびに生じる大脳皮質における網膜像の表象の変化を実装した. 提案モデルによる視覚探索のシミュレーションを行った結果, 従来モデルよりもターゲットの発見率が向上され, また, 視線移動の軌跡が一定の戦略を持った探索時の視線移動に似たパターンとなることが示された. [Abstract] The saliency map model is a mathematical expression of the characteristics of early visual information processing systems, which calculates the distribution of the saliency of a visual scene. Such models can predict the distribution of gaze positions (Itti & Koch 2000). However, the simulated gaze patterns show iterating profiles for long-range simulations. In order to avoid these unrealistic gaze patterns, the abstraction of inhibition of return (IOR) is important; TOR refers to the suppression of processing of objects that have recently been gazed. In peripheral vision, there is a phenomenon called facilitation of return (FOR), which refers as an enhancement of the visibility of particular visual attributes to make a search more efficient. Furthermore, the heterogeneous distribution of cone cells on the retina, which are extremely concentrated in the fovea, might affect the target search process. In this study, we modified the TOR operation using a Gaussian function proportion decrement with random peak value and the FOR operation by filtering with DOG (difference of Gaussians) functions during the early-stage processing of saliency map calculation. Moreover, input images were remapped to represent the cortical magnification in visual area 1. We tested the proposed model by the target detection rate in a visual search task simulation. The results indicate that the target detection rate was higher than that of the previous model, and the simulated scan-paths show similar profiles with the scan-path of visual search under certain strategy.本研究は近畿大学生物理工学部戦略的研究No.09-IV-10, 2010の助成を受けた.
  • サングラス型力メラによる手書きメモに関する検討, WATANABE EIJI, OZEKI TAKASHI, KOHAMA TAKESHI, 映像情報メディア学会年次大会講演予稿集(CD-ROM), 2011, ROMBUNNO.2-8,   2011 08 01 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201102253407741892
  • 注意の集中に伴うマイクロサッカード発生頻度の抑止, ENDO SHO, KOHAMA TAKESHI, Vision, 23, 3, 162, 163,   2011 07 20 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201102248542258740
  • 視覚属性に対する注意の修飾を考慮した視覚探索モデル, YANO KATSUYA, KOHAMA TAKESHI, Vision, 23, 3, 162, 162,   2011 07 20 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201102252800528193
  • サッカード眼球運動神経系の数理モデル, KOHAMA TAKESHI, YAMASHITA TERUHIKO, KAMIYAMA YOSHIMI, システム制御情報学会研究発表講演会講演論文集(CD-ROM), 55th, ROMBUNNO.H25-4,   2011 05 17 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201102283189857421
  • Saliency map model for visual attention in depth, GOUCHI TAIKI, KOHAMA TAKESHI, 映像情報メディア学会技術報告, 35, 16(HI2011 29-62/3DIT2011 17-50), 31, 34,   2011 03 08 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201102236205663065
    Summary:Previous saliency-based visual attention models dealt with the mechanism underlying attentional shifts in the early visual system. Such models can predict the distribution of gaze movements on the basis of saliency maps (Itti & Koch, 2000). Saliency maps are calculated on the basis of the distribution of color in and the orientation of input images. In recent studies, saliency-based models were modified to predict the gaze positions for moving objects. The data from psychophysical experiments indicate that singletons defined by depth easily pop out, indicating that the saliency of depth information is implicated in visual information processes. However, depth information is not considered in the calculations for saliency maps. In this study, we modified a saliency-based model with regard to using depth information for calculating the saliency map and deciding the gaze position. Our model can discriminate each object in the visual scene by referring to the region of shared depth and shift the gaze points from object to object on the basis of depth saliency. We analyzed the results for the visual search tasks in which some objects distributed to the depth space and obtained the scan order of objects by tracking the mouse cursor. The predicted scan orders for objects were found to be very similar to those obtained in the experimental results for the early selection phase. This indicates that the saliency of depth information may play an important role in visual search in depth space.
  • Ambiguous distractor that disrupts the control of fixation eye movements and attentional modulation, IRIE KUNIKO, KOHAMA TAKESHI, 映像情報メディア学会技術報告, 35, 16(HI2011 29-62/3DIT2011 17-50), 27, 30,   2011 03 08 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201102238249193271
    Summary:In this study, we conducted a numerical detection task involving the number of gaps in double rings, with dynamic random dot displays used as background motion stimuli. We controlled the intensive level of attention by regulating the contrast between the target rings and distractor rings. The task performance rates of the subjects were estimated as a relation of the percentage of coherence dots. Furthermore, we measured fixation eye movements during the tasks and analyzed the influence of subthreshold coherent motion information on involuntary eye movements such as microsaccades. Subthreshold coherent motion was found to deteriorate performance with regard to counting the gaps in the rings and the frequency of microsaccades regardless of the intensive level of attention concentration. This indicates that even if the top-down processes are sufficiently effective, bottom-up motion information can affect the control of attention and eye movements.
  • Embedding time tag in handwritten memorandum by using sunglasses type camera, WATANABE EIJI, OZEKI TAKASHI, KOHAMA TAKESHI, 映像情報メディア学会技術報告, 35, 16(HI2011 29-62/3DIT2011 17-50), 63, 66,   2011 03 08 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201102240499630612
    Summary:In taking hand-written memorandum, the taking process plays often important roles for recalling related information in addition of notations (words and figures) in the memorandum. In this report, we focus on the process through taking hand-written memorandum. Here, we propose image processing methods for embedding time tag in handwritten memorandum by using sunglasses type camera.
  • Neuronal network model of saccadic eye movement control system, YAMASHITA TERUHIKO, KOHAMA TAKESHI, KAMIYAMA YOSHIMI, 映像情報メディア学会技術報告, 35, 16(HI2011 29-62/3DIT2011 17-50), 23, 26,   2011 03 08 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201102241052295030
    Summary:In this study, we propose a mathematical model of the saccadic eye movement system based on the neuronal network characteristics of the substantia nigra pars reticulata (SNr), the intermediate layer of the superior colliculus (SC), and the brainstem neurons, all of which are deeply involved in the generation of saccades. The frontal eye field (FEF) is involved in the planning of the direction and amplitude of saccades, and the SC is involved in the generation of the commands for saccades and transmits them to the brainstem; subsequently, the ocular muscles contract to produce saccades. These cortices contain many functionally distinct cell types such as fixation neurons, buildup neurons, and burst neurons. The fixation neurons discharge while maintaining fixation. The buildup neurons become active during the preparatory stages of saccadic eye movements, and the burst neurons become active while executing the saccades. The firing properties of these types of cells have been well described. However, detailed information regarding their network, that is, how they communicate with each other through neural pulses, is not available. Our model can reproduce the properties of neural responses of saccade-related areas in express saccade tasks. In addition, the model can also reproduce the activity of the intermediate-layer neurons of the SC in antisaccade tasks. These results indicate the validity of the mathematical model for the mechanism underlying saccade generation.
  • Mathematical model of the visual attention system in the posterior parietal and prefrontal lobes, SUGIMOTO KEISUKE, KOHAMA TAKESHI, 映像情報メディア学会技術報告, 35, 16(HI2011 29-62/3DIT2011 17-50), 35, 38,   2011 03 08 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201102294348381222
    Summary:In this study, we formulated the activity of the lateral intraparietal (LIP) area neurons in the posterior parietal cortex, which controls the allocation of spatial attention. The LIP unit was integrated into the dorsal process of Hamker's model. We modified the dynamics of the frontal eye field (FEF) in the prefrontal cortex of the model in order to control the trigger for engaging or disengaging the focus of spatial attention; we assumed that the FEF is one of the pivotal areas for the inhibition of return (IOR) to the most recent fixation position. Our model reproduced the responses of the LIP neurons and oculomotor scanning behavior during the visual search tasks. The target detection rate of our model was 72%; the simulated scan paths obtained using our model closely resemble the experimental data obtained in monkeys.
  • Analysis of behaviors by lecturer and students in lecture based on image processing, WATANABE EIJI, OZEKI TAKASHI, KOHAMA TAKESHI, 電子情報通信学会技術研究報告, 110, 383(HCS2010 44-55), 53, 58,   2011 01 14 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201102292148129879
    Summary:In lectures, the relation between lecturer and students depend on not only contents but also speech and gestures by lectures. Moreover, the behaviors by students often represent how they have the interests for contents in the lecture and their behaviors have often a great influence on behaviors by lecturer. In this report, we discuss the analysis of behaviros by lecturer and students based on image processing at the initial stage. Here, the face and this direction by lecturer and students are detected by image processing methods. Furthermore, the behaviors are analyzed based on these features. Finally, we discuss the analysis results for a real lecture.
  • 2-8 A study on hand-written memorandum by using a sunglasses camera, WATANABE Eiji, OZEKI Takashi, KOHAMA Takeshi, PROCEEDINGS OF THE ITE ANNUAL CONVENTION, 2011, 0, 2, 8-1-_2-8-2_,   2011 , http://ci.nii.ac.jp/naid/130005674902
    Summary:In taking hand-written memorandum, the taking process plays often important roles for recalling related information in addition of notations in the memorandum. In this report, we focus on the process through taking hand-written memorandum. Here, we propose image processing methods for tracking the pen-position in handwritten memorandum by using sunglasses type camera.
  • 2-8 A study on hand-written memorandum by using a sunglasses camera, WATANABE Eiji, OZEKI Takashi, KOHAMA Takeshi, Proceedings of the ... ITE annual convention, 2011, 0, 2, 8-1-"2-8-2",   2011 , http://ci.nii.ac.jp/naid/110009598655
    Summary:In taking hand-written memorandum, the taking process plays often important roles for recalling related information in addition of notations in the memorandum. In this report, we focus on the process through taking hand-written memorandum. Here, we propose image processing methods for tracking the pen-position in handwritten memorandum by using sunglasses type camera.
  • マイクロサッカードと瞳孔径変動の解析に基づく覚醒水準の客観的評価, TANAKA TATSURO, KOHAMA TAKESHI, YOSHIDA HISASHI, 日本生体医工学会大会プログラム・論文集(CD-ROM), 50th, ROMBUNNO.O2-1-1,   2011 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201102297133738960
  • “A Binocular Vision Model for Solving Autostereograms”, Takeshi Kohama, Yoshihiro Hirata, Journal of the Institute of Image Electronics Engineers of Japan, 40, 5, 801, 807,   2011 , 10.11371/iieej.40.801, http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201102264654526858
    Summary:This study proposes a binocular vision model that reconstructs 3D structures from autostereograms. Our model is a modified version of the model by Hayashi et al., which cannot resolve the autostereograms, and serves to introduce fusion processes by vergence eye movements in order to obtain depth information from autostereograms. Since autostereograms have a periodic plane as the background, our model starts with the vergence motion of two windows corresponding to the left and right eyes to search maximal output of the binocular energy unit that produces autocorrelation-like patterns of the background. Once the optimum vergence angle has been determined, the model calculates paired or unpaired points using the same procedure employed in the model by Hayashi et al. The results indicate that the model can reconstruct 3D structures even from autostereograms, suggesting that the disparity detection system coordinates with the eye movement system to accurately derive depth perception. © 2011, The Institute of Image Electronics Engineers of Japan. All rights reserved.
  • Analysis of Behaviors by Students in e-Learning-Discrimination between reading and writing behaviors by image processing-, WATANABE EIJI, OZEKI TAKASHI, KOHAMA TAKESHI, 電子情報通信学会技術研究報告, 110, 334(ET2010 65-78), 15, 20,   2010 12 03 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201102270962385785
    Summary:In this report, we discuss image processing methods for discrimination between behaviors in reading contents and taking notes in e-Learning. First, scene images for contents can be recorded by a sunglasses-type camera. Next, a few features can be extracted based on color information from these images and the discrimination procedure can be executed by the discrimination analysis and the classification method by using multi-layered neural networks Finally, we evaluate the discrimination precision and discuss the relations among page transition, behaviors by students and their notes.
  • A statistical analysis of attentional effects on drift eye movements, Takeshi Kohama, Haruka Takenaka, Hisashi Yoshida, Naohiro Toda, Kyokai Joho Imeji Zasshi/Journal of the Institute of Image Information and Television Engineers, 64, 12, 1892, 1898,   2010 12 , 10.3169/itej.64.1892, http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201002284178960742
    Summary:Recent studies have demonstrated a close relationship between the frequency of microsaccades and covert attention shift. However, there are no arguments of attentional effect on drift movements during attentive or inattentive fixation. We examined whether visual attention has any influence on drift eye movements using statistical analysis of a time series of fixation eye movements. The results indicated that the power in the 3-4 Hz frequency range was enhanced when visual attention was dispersed over the parafoveal visual field. Furthermore, the amplitudes of the drift eye movements were reinforced immediately after the microsaccades, especially after square-wave jerks. These results suggest that microsaccades and drift eye movements are both controlled by higher order brain functions to acquire detailed visual information from the peripheral vision.
  • 視覚的注意の神経機構を考慮した視覚探索モデル(A visual search simulation by using a top-down feature feedback model), 杉本 圭佑, 小濱 剛, 神経化学, 49, 2-3, 765, 765,   2010 08
  • 抑制性フィードバックを考慮した顕著性マップ理論に基づく視線予測, KOHAMA TAKESHI, GOUCHI TAIKI, システム制御情報学会研究発表講演会講演論文集(CD-ROM), 54th, 0, ROMBUNNO.F12-2, 218,   2010 05 19 , 10.11509/sci.SCI10.0.218.0, http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201002274059040095
    Summary:我々の視線は,視野内の視覚的特徴量の分布(顕著性マップ)に基づいて予測できることが示されている.しかしながら,ボトムアップ処理のみによる予測は,実際の視線分布と大きく異なる場合が生じる.本研究では,繰り返し同じ場所を注視することを防ぐ復帰抑制のフィードバックにより,視線移動のたびに顕著性マップが更新されることを仮定して視線予測を行った.その結果,予測された視線分布は実測データとよく一致することが示された.
  • A binocular vision model considering vergence eye movements for solving autostereograms, HIRATA YOSHIHIRO, KOHAMA TAKESHI, 映像情報メディア学会技術報告, 34, 11(HI2010 49-73/3DIT2010 1-25), 39, 42,   2010 03 01 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201002219808511481
    Summary:This study proposes a binocular vision model that reconstructs 3D structures from autostereograms, single-image stereograms that connote disparity information into a single image. The previous binocular vision models involved inputting two images for the right and left eyes, and cannot detect depth information from the autostereograms. Our model is a modified version of the stereo model by Hayashi et al. and serves to introduce fusion processes by vergence eye movements in order to obtain depth information from autostereograms (Hayashi et al., 2004). Since autostereograms have a periodic plane as the background, our model starts with the vergence motion of two windows corresponding to the left and right eyes to search maximal output of the binocular energy unit that produces autocorrelation-like patterns of the background. Once the optimum vergence angle has been determined, the model calculates paired or unpaired points using the same procedure employed in the model by Hayashi et al. The results indicate that the model can reconstruct 3D structures even from autostereograms, suggesting that the disparity detection system coordinates with the eye movement system to accurately derive depth perception.
  • Characteristics of eye movements during visual search tasks with stimulus-independent thoughts, NISHIDA AYA, KOHAMA TAKESHI, 映像情報メディア学会技術報告, 34, 11(HI2010 49-73/3DIT2010 1-25), 35, 38,   2010 03 01 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201002297189018873
    Summary:Working inattentively often causes fatal accidents, and these are called "human errors." The detection and prediction of these errors is extremely difficult, and the measurement technology of inattentiveness has not yet been established. In this study, we investigate the effect of stimulus-independent thoughts (SITs) on the performance of visual search tasks. SITs are the streams of thoughts that are unrelated to immediate situations. In this study, the subjects memorized a combination of three numerical characters and their colors presented in advance, and the reaction time and the eye movements were measured while the subjects carried out visual search tasks after having maintained memories of the characters. The influence on reaction time and characteristics of eye movements was evaluated as a function of the number of distracters. As a result, the average reaction time and inter-saccadic intervals increased, and frequency of saccades decreased for saccades in the SIT condition on a naive subject, when compared to the No-SIT condition. The average frequency of microsaccades in the SIT condition slightly increased on all subjects. This suggests the possibility of an objective assessment of the potential danger of the human errors.
  • 視覚的注意の神経機構を考慮した視覚探索モデル, SUGIMOTO KEISUKE, KOHAMA TAKESHI, Vision, 22, 1, 113,   2010 01 20 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201002222343451151
  • Analysis of movements of students in e-Learning-Relations between eyes movements and understanding-, WATANABE EIJI, WATANABE NAOKI, KOHAMA TAKESHI, 電子情報通信学会技術研究報告, 109, 335(ET2009 51-91), 79, 84,   2009 12 04 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201002200356256354
    Summary:In this report, we discuss the relation between students' behaviour and their understanding for given contents in e-Learning. Here, we detect face eyes movements as the local features of students in each page. First, image processing methods for detection of eyes movements are proposed. Next, we discuss the relation between eyes movements and unserstanding for contents. Finally, we show some realations from experimental results.
  • Analysis of Movements of Students in e-Learning-Relations among face movements, page changes, and understanding-, WATANABE EIJI, WATANABE NAOKI, OZEKI TAKASHI, MUNEYASU MITSUJI, KOHAMA TAKESHI, 電子情報通信学会技術研究報告, 109, 335(ET2009 51-91), 73, 78,   2009 12 04 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201002268419897979
    Summary:In this report, we discuss the relation between students' behaviour and their understanding for given contents in e-Learning. Here, we detect face movements and page transition as the global features of students through all pages. First, image processing methods for detection of face movements are proposed. Next, we discuss the relation among face movements, page transition, and unserstanding for contents. Finally, we show some realations from experimental results.
  • 復帰抑制の特性を考慮した顕著性マップモデルの拡張による視線予測, GOUCHI TAIKI, KOHAMA TAKESHI, Mem Fac Biol Oriented Sci Technol Kinki Univ, 24, 45, 55,   2009 09 30 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=200902244551823758
  • Predicting human gaze shifts considering the inhibition of return using a modified saliency map model, 郷地 大紀, 小濱 剛, Memoirs of the Faculty of Biology-Oriented Science and Technology of Kinki University = 近畿大学 生物理工学部 紀要, 24, 45, 55,   2009 09 01 , http://ci.nii.ac.jp/naid/120005735098
    Summary:Departmental Bulletin Paper
  • 復帰抑制効果を考慮した顕著性マップ理論に基づく視線予測モデル, GOUCHI TAIKI, KOHAMA TAKESHI, Vision, 21, 3, 208,   2009 07 20 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=200902239658122694
  • エクスプレスサッカードの神経活動を再現する中脳神経系の数理モデル, YAMASHITA TERUHIKO, KOHAMA TAKESHI, KAMIYAMA YOSHIMI, Vision, 21, 3, 209, 210,   2009 07 20 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=200902287023025336
  • A statistical model analysis of attentional effects on drift eye movements before and after microsaccades, TAKENAKA HARUKA, KOHAMA TAKESHI, YOSHIDA HISASHI, TODA NAOHIRO, 映像情報メディア学会技術報告, 33, 17(HI2009 68-89/3DIT2009 17-38), 61, 64,   2009 03 18 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=200902242247639085
    Summary:Resent studies have demonstrated the important roles of involuntary fixation eye movements in visual perception. While microsaccades and drift eye movements maintain fixation, they are modulated by the visual attention system, and emphasize high spatial-frequency components of the visual information. In this study, employing a parametrical approach involving the use of a statistical autoregressive model, we analyzed the characteristics of frequency-domain properties of the drift eye movements before and after the occurrence of microsaccades. The results indicated that the low frequency components of the drift eye movements were reinforced immediately after the microsaccades. This tendency was more prominent when visual attention was dispersed over the parafoveal visual field. These results suggest that microsaccades and drift eye movements are controlled by higher order brain functions so as to acquire details of the visual information from the peripheral vision.
  • 脈絡のない考え事が目標探索時間に与える影響の客観的評価, NISHIDA AYA, KOHAMA TAKESHI, 日本生体医工学会大会プログラム・論文集(CD-ROM), 48th, ROMBUNNO.25AMO-25-5,   2009 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=200902201610459380
  • 弁別閾値以下の運動情報による高次の認知プロセスへの影響, IRIE KUNIKO, KOHAMA TAKESHI, 日本生体医工学会大会プログラム・論文集(CD-ROM), 48th, ROMBUNNO.25AMO-26-4,   2009 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=200902203846873201
  • 網膜神経細胞ネットワークモデルを用いた固視微動による知覚増強効果の検証, KOHAMA TAKESHI, YONEZAWA EIJI, Mem Sch Biol Orient Sci Technol Kinki Univ, 22, 61, 69,   2008 09 30 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=200902246337396322
  • Evaluation of concentration level of visual attention based on quantitative analysis on fixational eye movements, KOHAMA TAKESHI, システム制御情報学会研究発表講演会講演論文集(CD-ROM), 52nd, 0, 425, 426,   2008 05 16 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=200902280186491836
    Summary:本研究では,固視微動の発生機序における視覚的注意機構の関与の考察を目的として,注視点上に連続的に表示される文字の読み取り課題を実施し,このときの固視微動の統計解析を行った.その結果,注視位置の微小なジャンプであるマイクロサッカードは,注視位置への注意の集中度が高まるほど,発生頻度が抑制されることが示された.また,注視位置の揺らぎであるドリフト運動は,注意が散漫になるほど,特定の周波数帯域に増強が生じることが示された.
  • A verification of enhancement of visual perception caused by miniature eye movements based on a model of neural processing of retina, 米澤 瑛二, 小濱 剛, ITE technical report, 32, 15, 41, 44,   2008 03 06 , http://ci.nii.ac.jp/naid/40015986651
  • A mathematical model of saccadic eye movements based on neuronal activity in intermediate layers of superior colliculus, 藤川 淳平, 小濱 剛, ITE Technical Report, 32, 15, 45, 48,   2008 03 06 , http://ci.nii.ac.jp/naid/40015986652
  • A varification of enhancement of visual perception caused by miniature eye movements based on a model of neural processing of retina, ITE Technical Report, 32, 15, 41, 44,   2008 03
  • ドリフト眼球運動の統計解析に基づく視覚的注意の集中度の評価, TAKENAKA HARUKA, KOHAMA TAKESHI, TODA NAOHIRO, 日本生体医工学会大会プログラム・論文集(CD-ROM), 47th, ROMBUNNO.PS1-1-16,   2008 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=200902222854396000
  • 視覚的注意の集中がもたらすマイクロサッカードの抑制効果, HANDA TETSUYA, KOHAMA TSUYOSHI, 日本生体医工学会大会プログラム・論文集(CD-ROM), 47th, ROMBUNNO.PS1-1-15,   2008 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=200902262564494271
  • 上丘及び脳幹神経系細胞の応答特性を考慮したサッカード眼球運動系の数理モデル, FUJIKAWA JUMPEI, KOHAMA TAKESHI, KAMIYAMA YOSHIMI, 映像情報メディア学会冬季大会講演予稿集(CD-ROM), 2007, ROMBUNNO.10-3,   2007 11 27 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=200902200793186348
  • ドリフト眼球運動に見られる視覚的注意の影響, TAKENAKA HARUKA, KOHAMA TAKESHI, TODA NAOHIRO, 映像情報メディア学会冬季大会講演予稿集(CD-ROM), 2007, ROMBUNNO.10-4,   2007 11 27 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=200902274497924230
  • 10-3 A mathematical model of saccadic eye movement system based on neuronal activity in superior colliculus and basal ganglia, FUJIKAWA Jumpei, KOHAMA Takeshi, Kamiyama Yoshimi, ITE Winter Annual Convention, 2007, 2007, "10, 3-1",   2007 11 27 , http://ci.nii.ac.jp/naid/110009485282
    Summary:In this study, we propose a mathematical model of the saccadic system based on neuronal activity in superior colliculus and basal ganglia. Fixation neurons and build-up neurons in superior colliculus show antagonistic action and build-up neurons start to discharge sharply after termination of fixation neurons' activity. Our model can reproduce these properties of neural responses.
  • 10-4 Attentional effect on small drift eye movements during fixation, TAKENAKA Haruka, KOHAMA Takeshi, TODA Naohiro, ITE Winter Annual Convention, 2007, 2007, "10, 4-1",   2007 11 27 , http://ci.nii.ac.jp/naid/110009485283
    Summary:We examined whether the visual attention influenced the drift eye movement based on the statistical analysis. The results show that the frequency component of about 3-4[Hz] significantly decreased when attention was concentrated in the foveal area. This suggests that the concentration of attention onto the gazing object might enhance the stability of fixation.
  • A Development of the Miniature-Eye-Movement Model Accounting for the Influence of Visual Attention, 11, 27, 30,   2005
  • A Stady on an Objective Estimation of the Visual Stress based on a Miniature Eye Movement Model, 19, 25,   2005
  • 8-7 A simulation study of intrasaccadic perception based on an early visual system model, SHINOJIMA Ryota, KOHAMA Takeshi, KAMIYAMA Yoshimi, Proceedings of the ... ITE annual convention, 2004, 2004, "8, 7-1"-"8-7-2",   2004 08 02 , http://ci.nii.ac.jp/naid/110009469190
    Summary:Moving gratings which are invisible under fixation can be detected by executing saccades. We investigated the intrasaccadic visual processing by using an early visual system model which simulates retina-V1 projection. Our results show that contrast sensitivity of simulated V1 neurons was increased by executing sacades, indicating that intrasaccadic perception might occur on the early stage of visual processing.
  • 8-7 A simulation study of intrasaccadic perception based on an early visual system model, SHINOJIMA Ryota, KOHAMA Takeshi, KAMIYAMA Yoshimi, PROCEEDINGS OF THE ITE ANNUAL CONVENTION, 2004, 0, _8, 7-1_-_8-7-2_,   2004 , http://ci.nii.ac.jp/naid/130005673788
    Summary:Moving gratings which are invisible under fixation can be detected by executing saccades. We investigated the intrasaccadic visual processing by using an early visual system model which simulates retina-V1 projection. Our results show that contrast sensitivity of simulated V1 neurons was increased by executing sacades, indicating that intrasaccadic perception might occur on the early stage of visual processing.
  • 視覚的注意の影響を考慮した不随意性微小眼球運動モデルとそのシミュレーション解析, KOHAMA TAKESHI, 立石科学技術振興財団助成研究成果集, 11, 27, 30,   2002 09 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=201102133395777785
  • Population Dynamics of Sessile Bivalves Mytilus galloprovincialis and Xenostrobus securis in Hyper Eutrophicated Bay, Japan, KOHAMA Takeshi, MONTANI Shigeru, KAJIWARA Youko, YAMADA Machiko, Takeshi Kohama, Shigeru Montani, Youko Kajiwara, Machiko Yamada, Department of Life, Sciences Kagawa University, Department of Life, Sciences Kagawa University, Aqua Research Center Kitakyusyu City, Institute of Environmental Sciences, Aqua Research Center Kitakyusyu City, Institute of Environmental Sciences, NSUGAF, 67, 4, 664, 671,   2001 07 15 , 10.2331/suisan.67.664, http://ci.nii.ac.jp/naid/110003145321
    Summary:This study was conducted to clarify the population dynamics of the two predominant bivalves, Mytilus galloprovincialis and Xenostrobus securis, in Dokai Bay, Japan. Quantitative sampling of sessile animals and monitoring of water quality in Dokai Bay, were carried out from 1991 to 1992. We applied cohort allometry to these species to evaluate their population dynamics. These bivalves predominated on the vertical walls of the intertidal zone, and its maximum standing stock reached 18.3kg/m<SUP>2</SUP> for M. galloprovincialis and 10.6kg/m<SUP>2</SUP> for X. securis. With respect to M. galloprovincialis, it is suggested that most of the population inhibiting the inner bay will be spoiled by anoxic water in summer, and the population which is inhabiting the bay-mouse will act as a source population to support the whole population in Dokai bay. On the other hand, X. securis dominated the inner part of the bay, and a negative relationship was found between X. securis biomass and the number of sessile animal species in Dokai Bay. In this study, we found typical population dynamics of the sessile animal community in the eurtophicated area.
  • Image recognizability estimation based on eye movements analysis, 15, 149, 152,   2000 11
  • Image recognizability estimation based on eye movements analysis, KOHAMA Takeshi, ZHANG Jing, YAMAJI Kazutsuna, ISHIGURE Yasuo, SAKAI Hiroyuki, USUI Shiro, 生体・生理工学シンポジウム論文集, 15, 149, 152,   2000 10 13 , http://ci.nii.ac.jp/naid/10016711023
  • Quantitative Measurement of Visual Attention by Analyzing Human Miniature Eye Movements,   2000
  • Effects of the Blurred Images on Human Eye Movements, ZHANG Jing, KOHAMA Takeshi, YAMAJI Kazutsuna, ISHIGURE Yasuo, SAKAI Hiroyuki, USUI Shiro, IEICE technical report. ME and bio cybernetics, MBE99, 122, 53, 58,   1999 12 11 , http://ci.nii.ac.jp/naid/110003288299
    Summary:As multimedia equipment diverses, we have come to use the digital devices, such as over-head digital cameras, frequently. However, the blurred images produced by low-resolution digital equipment redounded the mischief on observer's visual system. In this paper, we attempt to evaluate the effects of blurred images by analyzing human eye movements during reading the blurred Japanese composition. The results showed that reading rate and amplitude of saccade increased, while fixations and their duration, Saccades and their amplitude and regressions saccades decreased depending on blurring level. Our findings suggest that the influence of blurred images on observer's visual system could be evaluated objectively by monitoring eye movements.
  • 古賀一男「眼球運動実験 ミニ・ハンドブック」, 臼井 支朗, 小濱 剛, 日本神経回路学会誌, 6, 1, 134, 134,   1999 03 , http://ci.nii.ac.jp/naid/130000439593
  • Quantitative Measurement of Visual Attention by Analyzing Human Miniature Eye Movements,   1999
  • Quantitatively Measuring Visual Attention by Analyzing Microsaccades ( Human Visual and Auditory Information), Kohama Takeshi, Shinkai Ken, Usui Shiro, The journal of the Institute of Image Information and Television Engineers, 52, 4, 571, 576,   1998 04 20 , 10.3169/itej.52.571, http://ci.nii.ac.jp/naid/110003692201
    Summary:To evaluate the effects of visual attention (VA) on human involuntary miniature eye movements (MEM), we analyzed the microsaccades (MSC), which are components of MEM, under the following three experimental conditions : 1) VA was focused on the foveal object, 2) VA was dispersed in the parafoveal visual field, and 3) VA was focused on one of the parafoveal objects. The results showed that the VA was not focused on the foveal object, the frequency and amplitude of the MSC increased, and the scatter of fixation widened. The results from 2) and 3) showed that the frequency of the MSC was grater in 2) and the mean amplitude of the MSC was similar for both conditions. When VA is not focused, the MSC occur more frequently, and when VA is focused on the foveal object, the amplitude of the MSC reduces. These results suggest that MEM are influenced by VA, and MSC may be used as an indicator of the attentional state. It will be possible to establish whether VA is focused or not on the basis of the analysis of MEM characteristics.
  • Quantitative measurement of visual attention by analysing microsaccades, T. Kohama, K. Shinkai, S. Usui, PERCEPTION, 27, 63, 64,   1998
  • A quantification of Visual Attention by Analyzing bf Human Microsaccades, 12, 193, 196,   1997 10
  • A quantification of Visual Attention by Analyzing Human Microsaccades, KOHAMA Takeshi, SHINKAI Ken, NAKAUCHI Shigeki, KAMIYAMA Yoshimi, TODA Naohiro, YAMADA Mitsuho, USUI Shiro, 生体・生理工学シンポジウム論文集, 12, 193, 196,   1997 09 04 , http://ci.nii.ac.jp/naid/10016711968
  • The Effect of Visual Attention on Miniature Eye Movement, KOHAMA Takeshi, SHINKAI Ken, NAKAUCHI Shigeki, KAMIYAMA Yoshimi, TODA Naohiro, YAMADA Mitsuho, USUI Shiro, ITE Technical Report, HIR97, 67, 39, 44,   1997 06 19 , http://ci.nii.ac.jp/naid/110003690707
    Summary:In order to consider the effects of the visual attention (VA) on human involuntary miniature eye movements (MEM), we analyzed the microsaccade (MSC) which is a component of MEM, under the following three experimental conditions : 1) VA was focused on the foveal object, 2) VA was dispersed in the parafoveal visual field, and 3) VA was focused on one of the parafoveal objects. As the result, when VA was not focused on the foveal object, both frequency and amplitude of MSC increased and the scatter of fixation became more widely. By comparison between the experimental condition 2) and 3), frequency of MSC was more often in 2) and mean amplitude of MSC was almost equal in both conditions. This is, when VA is not focused, MSC occurs more frequently, and when VA is focused on the foveal object, the amplitude of MSC become smaller. These results suggest that MEM is influenced by VA and MSC may be used as an indicator of attentional state. It will be possible to observe whether VA is focused or not on the basis of the analysis of MEM acceleration.
  • The Effect of Visual Attention on Miniature Eye Movement, KOHAMA Takeshi, SHINKAI Ken, NAKAUCHI Shigeki, KAMIYAMA Yoshimi, TODA Naohiro, YAMADA Mitsuho, USUI Shiro, ITE Technical Report, 21, 0, 39, 44,   1997 , http://ci.nii.ac.jp/naid/130005701792
    Summary:In order to consider the effects of the visual attention (VA) on human involuntary miniature eye movements (MEM), we analyzed the microsaccade (MSC) which is a component of MEM, under the following three experimental conditions : 1) VA was focused on the foveal object, 2) VA was dispersed in the parafoveal visual field, and 3) VA was focused on one of the parafoveal objects. As the result, when VA was not focused on the foveal object, both frequency and amplitude of MSC increased and the scatter of fixation became more widely. By comparison between the experimental condition 2) and 3), frequency of MSC was more often in 2) and mean amplitude of MSC was almost equal in both conditions. This is, when VA is not focused, MSC occurs more frequently, and when VA is focused on the foveal object, the amplitude of MSC become smaller. These results suggest that MEM is influenced by VA and MSC may be used as an indicator of attentional state. It will be possible to observe whether VA is focused or not on the basis of the analysis of MEM acceleration.
  • The relation between attention and saccadic latency during the visual information integration process across a saccade, Shinkai Ken, Kohama Takeshi, Saitoh Tsuyoshi, Yamada Mitsuho, Usui Shiro, Yoshida Tatsuo, テレビジョン学会年次大会講演予稿集, 32, 32, 413, 414,   1996 07 17 , http://ci.nii.ac.jp/naid/110004779180
    Summary:The relation between attention and the visual information integration process across a saccade was analyzed. A chinese character was exposed briefly twice. In the second exposure, the location of the square frame exposed in advance to attract attention and that of the character were varied in four ways. As a result, saccadic latency tended to take bimodal distribution, suggesting that attention plays an important role in the visual information integration.
  • An Analysis of Fixation Points Decideed in Aquisition Process of Visual Information, Kohama Takeshi, Saitoh Tsuyoshi, Shinkai Ken, Yamada Mitsuho, Usui Shiro, Yoshida Tatuo, IEICE technical report. ME and bio cybernetics, 95, 404, 19, 24,   1995 12 09 , http://ci.nii.ac.jp/naid/110003287099
    Summary:This study examined a contribution of visual system to the aquisition of visual information across saccades. In the experiment, when the observer made a saccade, the location of a Kanji character displayed on the CRT screen, was transferred at random distance and direction, or was kept at the original position. When the character was kept at the original position, the recognition rate of the character was high irrespective of the next fixation point. On the other hand, as the character was transferred from the original position, the rate was higher when the fixation point was landed around the center of the character than it landed on the other peripheral area, that is, decreased proportionally to the increase of distance between the gaze point and the center of the character. This suggests that the spatial attention before saccade might also involve in the process and the visual system may integrate the positional information into the visual feature information at somewhere in the process of visual information during saccade.
  • An analysis of fixation points during the character recognition process, SAITOH Tsuyoshi, KOHAMA Takeshi, YOSHIDA Tatsuo, テレビジョン学会年次大会講演予稿集, 31, 31, 321, 322,   1995 07 26 , http://ci.nii.ac.jp/naid/110004774449
    Summary:The role of the fixation points during character recognition process was analyzed when a Chinese character was briefly exposed twice in a trial. The second exposure position of the character was transferred from the first. As the displacement of the second exposure position increases, probability of correct recognition declines.
  • Analysis of visual systems's information acquisition ability before and after a saccade, Saitoh Tsuyosi, Shinkai Ken, Kohara Takeshi, Hatano Tomoyuki, Yoshida Tatsuo, Proceedings of the IEICE General Conference, 1995, 1,   1995 03 27 , http://ci.nii.ac.jp/naid/110003267316
    Summary:人間の視覚系は、150〜300msecの固視と数10msecの素早い眼球の運動(saccade)を繰り返して外界の情報を処理している。視覚系の情報獲得能力はsaccade中に低下することが一般的に知られている。また、視覚系は、中心視以外の周辺部分に何らかの変化が生じた際、実際にsaccadeが発生する以前の段階で新たに予定された注視点を中心として情報を獲得することが明らかになっている。しかし、saccade発生前後における視覚系の情報獲得能力の時間的推移に関して定量的な解析はなされていなかった。そこで本研究では、光学的な方法により注視点の位置を客観的に測定する装置と画像を短時間呈示するシステムとを組合わせ、saccadeの発生前後のある時刻に1文字の平仮名を一定の期間だけ短時間呈示する実験を行なった。この時の呈示時刻と平仮名の認識率との関係を求め、saccade発生前後の視覚系の情報獲得能力の時間的推移について考察した。
  • An analysis of eye movements on charactor recognition, Kohama Takeshi, Hatano Tomoyuki, Saitoh Tsuyoshi, Yoshida Tatsuo, IEICE technical report. Image engineering, 94, 96, 9, 16,   1994 06 16 , http://ci.nii.ac.jp/naid/110003195171
    Summary:The relationship between the position of the fixation point and the position of recognized letters was analyzed during several letters were briefly exposed.,While the fixation point is fixed and no eye movement is planned letters around the fixation point are correctly recognized.While the fixation point is fixed but a′s accade is planned,letters around the next fixation point are recognized.After a saccade,the recognition of letters around the new fixation point is continued in the visual system.
  • An analysis of eye movements on character recognition, Kohama Takeshi, Hatano Tomoyuki, Saitoh Tsuyoshi, Yoshida Tatsuo, ITEJ Technical Report, 18, 32, 9, 16,   1994 06 16 , http://ci.nii.ac.jp/naid/110003679080
    Summary:The relationship between the position of the fixation point and the position of recognized letters was analyzed during several letters were briefly exposed. While the fixation point is fixed and no eye movement is planned letters around the fixation point are correctly recognized. While the fixation point is fixed but a saccade is planned, letters around the next fixation point are recognized. After a saccade, the recognition of letters around the new fixation point is continued in the visual system.
  • Measurement of fixation points on briefly exposed characters, Nomura Takuya, Kohama Takeshi, Yoshida Tatsuo, テレビジョン学会年次大会講演予稿集, 28, 28, 189, 190,   1992 07 28 , http://ci.nii.ac.jp/naid/110004778325
    Summary:To clarify the role of fixation points in human character recognition, subject's eye movements were measured while he was observing a briefly exposed character. It was found that more than 100ms exposure time was necessary to recognize a character. However, it is still not clear whether the result of recognition affects the fixation points.
  • Analysis of Behaviors of Participants in Meetings, Eiji Watanabe, Takashi Ozeki, Takeshi Kohama, Advances in Intelligent Systems and Computing, 715, 427, 438,   2018 , 10.1007/978-3-319-73210-7_52, https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85040197378&origin=inward
    Summary:In this paper, we analyze the behaviors of participants in two types of meetings (brainstorming and decision-making). First, we introduce the use of participant behavior based on facial movement. Next, we propose a method for modeling the behaviors of participants based on multi-layered neural networks. Lastly, based on our experimental results, we discuss the relationships between the meeting phase, participant behaviors, and the model parameters in these two types of meetings. Our results show the parameters in the above models to be strongly related to the behaviors and ideas of the participants in these two types of meetings.
  • Analysis of pupil response and event-related potential during a fast-paced cognitive and attention task, Hisashi Yoshida, Takeshi Kohama, PERCEPTION, 44, 113, 113,   2015 08 , Refereed
  • A simulation study of the effects of fixation eye movements on retinal responses, Takeshi Kohama, Makoto Nishino, Hisashi Yoshida, PERCEPTION, 44, 166, 166,   2015 08 , Refereed
  • An analysis of resting-state NIRS responses evoked by low-passed dynamic randam-dot patterns, Hiroki Namikawa, Takeshi Kohama, Hisashi Yoshida, Transactions of Japanese Society for Medical and Biological Engineering, 52, 383, O-384,   2014 08 17 , 10.11239/jsmbe.52.O-383, http://www.scopus.com/inward/record.url?partnerID=HzOxMe3b&scp=84939424058&origin=inward
    Summary:Recent brain science studies have focused on functional connectivity in functional networks. However, experimental conditions are not sufficiently controlled to reduce individual differences in order to make experimental data stable because the definition of resting states is ambiguous. The purpose of this study is to investigate a more stable method of measuring restiong state brain activity. Subjects performed a 2-back task to facilitate activity of the prefrontal cortex temporally. As half-closed eyes help induce a meditative state, we presented low-passed dynamic random-dot patterns (DRD) in the background to make subjects' vision similar to what they would see if their eyes were half-closed. We measured subjects' brain activity with a NIRS device while subjects observed DRDs for 180 seconds. As a result, prefrontal activity decreased earlier as DRDs increased in blurriness. Moreover, brain activity reactivated immediately after reaching the baseline. This suggests that our method may induce stable resting states effectively.
  • The relationship between spatial extent of focal attention and latencies of microsaccades, Yuji Kanoh, Takeshi Kohama, Sho Kikkawa, Hisashi Yoshida, Transactions of Japanese Society for Medical and Biological Engineering, 52, 53, O-54,   2014 08 17 , 10.11239/jsmbe.52.O-53, http://www.scopus.com/inward/record.url?partnerID=HzOxMe3b&scp=84939421280&origin=inward
    Summary:Recent studies have indicated that mechanisms of microsaccades, involuntary small shifts in gaze, are affected by attention. Most studies have shown that mocrosaccade rates increase with a shift of attention, while others have shown that occurrence of mocrosaccades is inhibited when attention is in foveal region. In this study, we calculated latencies of microsaccades and analyzed the relationship between the spatial extent of attention and latencies of microsaccades. Subjects performed rapid serial visual presentation tasks. Targets were defined by differences in luminance contrast from distractors. We controlled focal attention under two conditions: high-contrast (HC) and low-contrast (LC). Results show that the histogram of latencies of microsaccades have two peaks only in the LC. The second peak was delayed approximately 0.3 sec from the peak of the HC. These results suggest that microsaccades are inhibited when attention is concentrated in foveal region, and disinhibited when attention is disengaged.
  • The effects of attentional concentration on dynamic characteristics of drift eye movements, Takeshi Kohama, Daisuke Noguchi, Sho Kikkawa, Hisashi Yoshida, I-PERCEPTION, 5, 4, 310, 310,   2014 , Refereed
  • Paper analysis of reading and writing behaviors for digital contents, Eiji Watanabe, Takashi Ozeki, Takeshi Kohama, Proceedings of IEEE International Conference on Teaching, Assessment, and Learning for Engineering, TALE 2012, C4, C9,   2012 , 10.1109/TALE.2012.6360403, http://www.scopus.com/inward/record.url?partnerID=HzOxMe3b&scp=84871522684&origin=inward
    Summary:In this paper, we discuss the change of page number and image processing methods for discrimination between behaviors in reading contents and taking notes for contents on the display. First, scene images for contents can be recorded by a sunglasses-type camera. Next, a few features can be extracted based on color information from these images and the discrimination procedure can be executed by the discrimination analysis and the classification method by using multi-layered neural networks. Finally, we evaluate the discrimination precision and discuss the relations among page transition, behaviors by students and their notes. This electronic document is a "live" template. The various components of your paper (title, text, heads, etc.) are already defined on the style sheet, as illustrated by the portions given in this document. © 2012 IEEE.
  • Inhibition of microsaccade rate caused by increase in visual attention, Sho Endo, Takeshi Kohama, NEUROSCIENCE RESEARCH, 71, E351, E351,   2011 , Refereed, 10.1016/j.neures.2011.07.1538
  • Visual search model considering spatial modification of visual attributes, Katsuya Yano, Takeshi Kohama, NEUROSCIENCE RESEARCH, 71, E256, E256,   2011 , Refereed, 10.1016/j.neures.2011.07.1116
  • Analysis of behaviors by lecturer and students in lectures based on piecewise auto-regressive modeling, Eiji Watanabe, Takashi Ozeki, Takeshi Kohama, Proceedings - 2011 IEEE 7th International Conference on Intelligent Computer Communication and Processing, ICCP 2011, 385, 390,   2011 , 10.1109/ICCP.2011.6047902, http://www.scopus.com/inward/record.url?partnerID=HzOxMe3b&scp=80755142960&origin=inward
    Summary:In this paper, we discuss the analysis of behaviors by lecturer and students in lectures. In lectures, the relationships between lecturer and students depend on not only contents but also the loudness of speech and gestures by lecturer. The behaviors consisting of head and eye movements by students can often represent how they have the interest with the lecture. First, we extract the loudness of speech and the face direction as behaviors by lecturer and the face direction as behaviors by students. Next, we construct piecewise auto-regressive (AR) models for their behaviors. Here, the piecewise AR models can be constructed based on the residual error. Finally, we show the analysis results for a real lecture based on the piecewise AR modeling. © 2011 IEEE.
  • A visual search simulation by using a top-down feature feedback model, Keisuke Sugimoto, Takeshi Kohama, NEUROSCIENCE RESEARCH, 68, E434, E435,   2010 , Refereed, 10.1016/j.neures.2010.07.1926
  • Stimulus-independent thoughts affect visual search task performances, Aya Nishida, Takeshi Kohama, NEUROSCIENCE RESEARCH, 65, S193, S193,   2009 , Refereed, 10.1016/j.neures.2009.09.1048
  • A gaze prediction model considering the inhibition of return based on the saliency map theory, Taiki Gochi, Takeshi Kohama, NEUROSCIENCE RESEARCH, 65, S109, S109,   2009 , Refereed, 10.1016/j.neures.2009.09.497
  • A neural model of discharge profiles in the midbrain to reproduce express saccades, Teruhiko Yamashita, Takeshi Kohama, Yoshimi Kamiyama, NEUROSCIENCE RESEARCH, 65, S171, S171,   2009 , Refereed, 10.1016/j.neures.2009.09.895
  • An ambiguous distracter disrupts the recognition of nonverbal graphic symbols, Kuniko Irie, Takeshi Kohama, NEUROSCIENCE RESEARCH, 65, S193, S193,   2009 , Refereed, 10.1016/j.neures.2009.09.1047
  • Attentional effects on microsaccadic eye movements, T Kohama, S Usui, CAHIERS DE PSYCHOLOGIE COGNITIVE-CURRENT PSYCHOLOGY OF COGNITION, 21, 4-5, 377, 395,   2002 10 , http://www.scopus.com/inward/record.url?partnerID=HzOxMe3b&scp=0038505854&origin=inward
    Summary:Visual attention (VA) greatly influences saccadic eye movements. However, little is known about the effect of VA on fixational eye movements. To address this problem, we analyzed microsaccades, small involuntary saccadic eye movements, under the following three experimental conditions: (i) VA focused on a foveal object, (ii) VA dispersed over a parafoveal visual field, and (iii) VA focused on a parafoveal object. Results from a study of four subjects showed that the frequency and mean amplitude of microsaccades were notably reduced under condition (i). Microsaccades were more frequent under condition (ii) than under condition (iii), although the mean microsaccade amplitudes were similar under the two conditions. This suggests that microsaccades occur more frequently when VA is not focused on a particular point in the visual field, and that the mean amplitude of microsaccades decreases when VA is focused on the foveal area of the visual field. The mean peak velocity of microsaccades was significantly greater under condition (i) than under conditions (ii) or (iii), indicating that attentional focus in the foveal area influences the dynamics of the eye movement system. Our findings suggest that focusing attention on the foveal area may affect fixation stability.
  • Quantitatively measuring visual attention by analyzing microsaccades, Takeshi Kohama, Ken Shinkai, Shiro Usui, Kyokai Joho Imeji Zasshi/Journal of the Institute of Image Information and Television Engineers, 52, 4, 571, 576,   1998 , 10.3169/itej.52.571, http://www.scopus.com/inward/record.url?partnerID=HzOxMe3b&scp=0032043241&origin=inward
    Summary:To evaluate the effects of visual attention (VA) on human involuntary miniature eye movements (MEM), we analyzed the microsaccades (MSC), which are components of MEM, under the following three experimental conditions: 1) VA was focused on the foveal object, 2) VA was dispersed in the parafoveal visual field, and 3) VA was focused on one of the parafoveal objects. The results showed that the VA was not focused on the foveal object, the frequency and amplitude of the MSC increased, and the scatter of fixation widened. The results from 2) and 3) showed that the frequency of the MSC was grater in 2) and the mean amplitude of the MSC was similar for both conditions. When VA is not focused, the MSC occur more frequently, and when VA is focused on the foveal object, the amplitude of the MSC reduces. These results suggest that MEM are influenced by VA, and MSC may be used as an indicator of the attentional state. It will be possible to establish whether VA is focused or not on the basis of the analysis of MEM characteristics.
  • An analysis of saccades during Kanji-recognition tasks, Takeshi Kohama, Ken Shinkai, Tsuyoshi Saitoh, Mitsuho Yamada, Shiro Usui, Tatsuo Yoshida, Kyokai Joho Imeji Zasshi/Journal of the Institute of Image Information and Television Engineers, 51, 8, 1308, 1318,   1997 , 10.3169/itej.51.1308, http://www.scopus.com/inward/record.url?partnerID=HzOxMe3b&scp=3943083539&origin=inward
    Summary:In order to consider the effects of spatial attention on human saccadic eye movements, we analyzed peak velocity, duration, latency and amplitude of saccades during Kanji-recognition tasks. The results suggest that the choice of region allocated for spatial attention has no effect on the characteristics of saccades. The distributions of saccadic latency showed 1 to 3 peaks, and their peak values were consistent with the results of earlier studies. Because of these facts, we consider that there are basic phases for making saccades regardless of the complexity of the tasks. The relation between saccadic latency and amplitude shows that a longer latency leads to a smaller amplitude. This suggests that the state of spatial attention before execution of a saccade affects its amplitude. Based on these results, a schematic model of the brain system for generating of saccades is proposed, and the process of generating saccades is hypothesized using this conceptual model.
  • Analysis of fixation points and spatial attention in the process of visual information integration across a saccade, Takeshi Kohama, Tsuyoshi Saitoh, Ken Shinkai, Mitsuho Yamada, Shiro Usui, Tatsuo Yoshida, Terebijon Gakkaishi (Journal of the Institute of Television Engineers of Japan), 50, 11, 1781, 1789,   1996 , 10.3169/itej1978.50.1781, http://www.scopus.com/inward/record.url?partnerID=HzOxMe3b&scp=0030288918&origin=inward
    Summary:This study examines a contribution of the visual system to the acquisition of visual information during saccadic eye movements (saccade). In the experiment, when the observer made a saccade, the location of a Kanji character displayed on a CRT screen was transferred a random distance and direction, or was kept at the original position. When the character was transferred to a new position, the recognition rate of the character decreased proportionally to the increase in distance between the fixation point after the saccade and the center of the character, in comparison with the case when the character was kept at the original position. We attempted to control the spatial attention during the same tasks. The result suggests that the spatial attention before a saccade might also be involved in the process of visual information acquisition during saccades and the visual system may integrate the positional information into the visual feature information.

Research Grants & Projects

  • Ministry of Education, Culture, Sports, Science and Technology, Grants-in-Aid for Scientific Research(基盤研究(C)), An objective evaluation of the influence of ``undetectable motions'' on cognitive functions by the analyses of fixation eye movements, The purpose of this study is to evaluate the influence of ``undetectable motions'', the motion information under the perception threshold, on cognitive functions by statistical analyses of the property of fixation eye movements. Subjects performed rapid serial visual presentation (RSVP) tasks with undetectable or ambiguous motions in the background while maintaining their fixation. We evaluated the influence of these motions on top-down attention mechanism by analyzing fixation eye movements. The results suggest that microsaccade rates were correlated with subliminal motion information, and fluctuations of drift eye movements were modulated by low-contrast motions in the peripheral vision.