Taya, Shuichiro



Faculty of Law (Hiyoshi)


Associate Professor

Career 【 Display / hide

  • 2005

    Kanazawa University, 技術員・研究員

  • 2008

    University of Southampton, School of Psychology

  • 2009

    University of Surrey, Research Fellow

  • 2010.12

    Queen Mary University of London, Research Fellow

  • 2012.04

    Taisho University, 専任講師

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Academic Background 【 Display / hide

  • 1996.04

    Kyushu University, 文学部, 心理学専攻

    University, Graduated

  • 2000.04

    Kyushu University, 人間環境学府, 行動システム心理学コース

    Graduate School, Completed, Master's course

  • 2002.04

    Kyushu University, 人間環境学府, 行動システム心理学コース

    Graduate School, Withdrawal after completion of doctoral course requirements, Doctoral course

Academic Degrees 【 Display / hide

  • 修士(人間環境学), Kyushu University, Coursework, 2002.03

  • 博士(心理学), Kyushu University, 2007.07


Research Areas 【 Display / hide

  • Humanities & Social Sciences / Experimental psychology

  • Humanities & Social Sciences / Experimental psychology

Research Keywords 【 Display / hide

  • 両眼立体視

  • Individual difference

  • 奥行き知覚

  • Experimental Psychology

  • 眼球運動

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Books 【 Display / hide

  • 図説視覚の事典

    日本視覚学会, 朝倉書店, 2022.11,  Page: vi, 357p

  • 有斐閣現代心理学辞典

    有斐閣, 2021.02,  Page: 996

  • 感性認知: アイステーシスの心理学

    田谷修一郎, 北大路書房, 2016.03,  Page: 215

    Scope: 第2章 絵画における三次元空間の表現と知覚

  • 感覚知覚心理学(朝倉心理学講座 6)

    中溝幸夫・田谷修一郎, 朝倉書店, 2008.05,  Page: 260

    Scope: 第6章「3次元空間の知覚」

  • 錯視の科学ハンドブック

    三浦佳世, 田谷修一郎, 東京大学出版会, 2005.02,  Page: xvii, 599p, 図版[24]p

    Scope: 第5章「錯視の応用」

Papers 【 Display / hide

  • The bumpy circle illusion: Apparent shape-distortion of filled circles placed on a checkered patter

    Shuichiro Taya, Masaya Ishikawa

    Journal of Illusion 4 2024.01

    Research paper (scientific journal), Joint Work, Lead author, Corresponding author, Accepted

     View Summary

    A new visual illusion in which circles placed on the checkered-pattern background appear to be polygons is reported. In this article, we first demonstrated that the apparent distortion of circles in this ‘bumpy circle illusion (BCI)’ depends on the luminance difference between the circles and the components of the background. Then, with the aim of clarifying the mechanism that causes this phenomenon, the ‘low-pass filtering theory’ the ‘segmentation theory’, the ‘corner effect theory’, and the ‘completion theory’ were investigated. As a result, the low-pass filtering theory and the completion theory were rejected because they predicted the occurrence of the illusion in some modulated BCI figures that produced no illusion. The ‘segmentation theory’, which postulated that the same mechanism as in the curvature blindness illusion produces BCI, was also rejected because the same luminance assignment as for BCI image components does not produce the curvature blindness illusion. In addition, the curvature of lines appears to deform in the curvature blindness illusion, whereas the BCI does not produce an illusion of line circles, which also shows the difference between the two phenomena. The ‘corner effect theory’ is the most promising because it correctly predicts (1) how the apparent distortion of the circles appears and (2) the presence/absence of illusion with the outline circles depending on the checkerboard luminance alteration cycles inside and outside of the circles. However, the corner effect theory can only be justified if it is assumed that the strength of the effect is different depending on whether the checkered pattern is applied to the inside or outside of the circles. Whether such asymmetry does exist and the reason why the asymmetry occurs needs further investigation.

  • Do observers use their own interpupillary distance in disparity scaling?.

    Shuichiro Taya

    Optical Review 30 ( 1 ) 41 - 49 2023.01

    Research paper (scientific journal), Single Work, Lead author, Last author, Corresponding author, Accepted,  ISSN  13406000

     View Summary

    This study investigated whether the individual difference in the observer’s interpupillary distance (IPD) could cause the individual difference in perceived depth in binocular stereopsis. The horizontal retinal disparity (HRD) is one of the most potent depth cues, but the visual system could not uniquely estimate the metric depth from HRD alone. This is because the size of HRD is determined as a function not only of the size of external depth but also of the viewing distance and IPD. Thus to perceive depth veridically from HRD, observers need to adjust the scaling gain (i.e. the magnification factor when converting HRD to perceived depth), taking their IPD into account. To investigate whether the visual system performs such gain calibration, we examined the relationship between IPD size and perceived depth when observing stereograms (i.e. the visual stimulus of fixed HRD) at a fixed viewing distance with 54 observers. The results showed a significant correlation between perceived depth and IPD. This is consistent with the prediction based on the geometric relationship between depth, HRD, IPD, and viewing distance, suggesting that the visual system does calibrate the scaling gain based on the observer’s IPD. However, the measured results did not fully agree with the predictions from the geometry. The results were discussed, focusing on the errors in the estimation of scaling distance.

  • Orientation-specific learning of the prior assumption for 3D slant perception

    Shuichiro Taya, Masayuki Sato

    Scientific Reports 8 ( 1 )  2018.12

    Research paper (scientific journal), Joint Work, Lead author, Accepted

     View Summary

    We usually interpret a trapezoidal image on our retina as a slanted rectangle rather than a frontoparallel trapezoid, because we use a statistical assumption (i.e. rectangles are more common than trapezoids), called a ‘prior’, for recovering the 3D world from ambiguous 2D images. Here we report that the shape prior for recovering 3D slant can be updated differently depending on the slant axis orientation (horizontal vs. vertical). The participants were exposed to a variety of trapezoidal images surrounded by a stereoscopic reference plane. The perspective transformation of the images was interpreted as 2D shape, rather than 3D slant because the surrounding plane enhanced disparity. We found that, after continuous exposure to such images, the participants relied less on the shape information for recovering 3D slant, suggesting the update of priors via experience (i.e., rectangles are less common than trapezoids). Importantly, the learning effect was context (slant-axis) specific although partially transferred across contexts; the training with horizontal-axis slant reduced the reliance on perspective even in vertical-axis slant estimation but not vice versa. The results suggest that context-specific training is vital to update the prior for the horizontal-axis slant, whereas it is not required to update the prior for a vertical-axis slant.

  • The influence of simultaneous multiple exposure on the mere exposure effect

    Taiichiro Uechi, Shuichiro Taya

    International Journal of Affective Engineering 15 ( 3 ) 343 - 349 2016.07

    Research paper (scientific journal), Last author, Corresponding author, Accepted,  ISSN  2187-5413

  • The individual differences in spatial perception caused by the differences in our bodily features

    Shuichiro Taya

    The Japanese Journal of Psychonomic Science 34 ( 2 ) 269 - 275 2016.04

    Research paper (conference, symposium, etc.), Single Work, Lead author, Last author, Corresponding author

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Papers, etc., Registered in KOARA 【 Display / hide

Reviews, Commentaries, etc. 【 Display / hide

  • 「新宿東口の猫」はなぜ立体的に見えるのか?


    Vision (The Vision Society of Japan)  34 ( 3 ) 84 - 87 2022.07

    ISSN  09171142

  • Increase in numerical magnitude from left-to-right shortens perceived time

    Kyoshiro Sasaki, Shuichiro Taya, Kayo Miura

    2013 International Conference on Biometrics and Kansei Engineering (ICBAKE) (IEEE)     113 - 116 2013

     View Summary

    The present study examined the effect of viewing spatially ordered numbers on time perception. Five single digits were presented as the test stimuli. The digits were chosen from 1 to 9 and presented in a horizontal line. We tested the arrangement of the digits in three conditions, where numerical magnitude of the digits increased from left to right (Small-Large condition), decreased from left to right (Large-Small condition), or in a random order (Random condition). Observers were asked to reproduce the presentation duration of the stimuli by pressing the spacebar for as long as the stimulus had been presented. The results showed that the reproduced time was shorter in the Small-Large condition than the other two conditions. The effect of numerical order on time perception is discussed from the perspective of the mental representation of numbers and fluency of cognitive processing.

  • Numbers in our mental space

    TAYA Shuichiro, SENO Takeharu, PASQUALOTTO Achille, PROULX Michael, SUNAGA Shoji, ITO Hiroyuki

    ITE Technical Report (The Institute of Image Information and Television Engineers)  36 ( 52 ) 1 - 4 2012.11

    ISSN  1342-6893

     View Summary

    Numbers are represented as increasing from left to right in our mental space (mental number line). Here we report two studies which investigated the number-line representation in our mental space. In the first study, we tested how numbers are represented in the depth dimension with using forward/backward vection (illusory self-motion sensation). The results suggest that numbers were represented as they increase from front to back. In the second study, by asking congenital blinds the random number generation task, we examined whether the mental number line is inherently incorporated in our cognitive system. The results suggest that the mental number line was developed via past visual experience.

  • Learning in stereopsis: effects of a reference frame on weighting of stereo and perspective depth cues

    佐藤 雅之, 小田崎 光雄, 田谷 修一郎

    ITE technical report (映像情報メディア学会)  32 ( 15 ) 81 - 83 2008.03

    ISSN  1342-6893

  • Hemodynamic responses corresponding to the stimulated visual field : measurements with 24 channel NIRS

    TAYA Shuichiro, MAEHARA Goro, KOJIMA Haruyuki

    IEICE technical report (The Institute of Electronics, Information and Communication Engineers)  106 ( 328 ) 49 - 52 2006.10

    ISSN  0913-5685

     View Summary

    We measured the hemodynamic responses in the occipital regions during visual stimulation with near-infrared spectroscopy (NIRS). The stimulus was a radial checker pattern (12 deg in radius) of which contrast reversed at 7.5Hz, and was presented to the whole or one quadrant of the visual field. In each measurement session, a 15s stimulating period and a 30s resting period were repeated five times. Hemodynamic changes at the occipital regions were measured with 4×4 probes which were separated from each other by 3cm. The results of the two-session measurements for each visual field showed that oxy-hemoglobin (Hb) concentration increased whereas deoxy-Hb concentration decreased during the stimulating period. Those changes in the Hbs were corresponding to the stimulated visual field, but only when the lower quadrants were stimulated.

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Research Projects of Competitive Funds, etc. 【 Display / hide

  • Geometrical illusion as anamorphosis


    Keio University, Keio University Academic Development Funds for Individual Research, Principal investigator

  • A psychophysical study on functional aspects of visual filling phenomena


    MEXT,JSPS, Grant-in-Aid for Scientific Research, Shuichiro Taya, Grant-in-Aid for Scientific Research (C), Principal investigator

  • 先行マスク刺激が誘発する視覚的充填現象:「気づきの欠如」説の検討


    Keio University, Keio University Academic Development Funds, Principal investigator

  • 奥行き情報の矛盾が生み出す超立体感:「二重否定仮説」の検討


    MEXT,JSPS, Grant-in-Aid for Scientific Research, Shuichiro Taya, Grant-in-Aid for Scientific Research (C), Principal investigator

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  • 先行マスク刺激が誘発する視覚的充填現象の空間特性分析


    Keio University, Keio University Academic Development Funds, Shuichiro Taya, Principal investigator

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Awards 【 Display / hide

  • 第15回 錯視・錯聴コンテスト 入賞

    石川将也・臼井健太郎・田谷修一郎, 2023.12, 幻の集中線と円の歪み:拡大・縮小する円配列に現れる二種の錯視

  • 第15回 錯視・錯聴コンテストグランプリ

    臼井健太郎・石川将也・田谷修一郎, 2023.12, 重ね市松回転錯視 -回転によって変形する主観的輪郭-

  • President's Award for Good Practice in Online Courses

    田谷修一郎, 2021.03, Tokyo University

    Type of Award: Other

  • Best illusion of the year 2017 top 10 finalist

    Shuichiro Taya, 2017, Mask Induced Filling-out

  • 第7回錯視コンテストグランプリ

    田谷修一郎, 2015

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Other 【 Display / hide

  • 小学館『小学一年生』2020年11月号巻頭特集 「さくしのせかい」監修


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  • NHK Eテレ0655&2355 おはようソング・おやすみソング『錯視のなぞめき』監修


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Courses Taught 【 Display / hide











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Committee Experiences 【 Display / hide

  • 2017.04

    幹事, 日本基礎心理学会

  • 2015.11

    委員長, 日本基礎心理学会若手研究者特別委員会

  • 2013.12

    委員, 日本基礎心理学会若手研究者特別委員会