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Solving visual correspondence between the two eyes via domain-based population encoding in nonhuman primates

  1. Anna W. Roea,b,c,d,e,h
  1. aInterdisciplinary Institute of Neuroscience and Technology, Qiushi Academy for Advanced Studies, Zhejiang University, Hangzhou 310029, China;
  2. bCollege of Biomedical Engineering and Instrument Science, Key Laboratory of Biomedical Engineering of Ministry of Education, Zhejiang University, Hangzhou 310027, China;
  3. cSchool of Medicine, Zhejiang University, Hangzhou 310058, China;
  4. dCollege of Biomedical Engineering and Instrument Science, Zhejiang Provincial Key Laboratory of Cardio-Cerebral Vascular Detection Technology and Medicinal Effectiveness Appraisal, Zhejiang University, Hangzhou 310027, China;
  5. eDepartment of Psychology, Vanderbilt University, Nashville, TN 37203;
  6. fState Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing 100875, China;
  7. gDepartment of Physiology, Niigata University, School of Medicine, Chuo-ku, Niigata 951-8510, Japan;
  8. hDivision of Neuroscience, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006
  1. Edited by Tony Movshon, New York University, New York, NY, and approved November 6, 2017 (received for review August 31, 2016)


A long-standing problem in visual depth perception is how corresponding features between the two eyes are matched (the “binocular correspondence problem”). Here, we show, using optical imaging in monkey visual cortex, that this computation occurs in the near and far disparity domains of V2, and that functional organization in V2 might facilitate the pooling of disparity signals that can reduce false matches to solve the binocular correspondence problem.


Stereoscopic vision depends on correct matching of corresponding features between the two eyes. It is unclear where the brain solves this binocular correspondence problem. Although our visual system is able to make correct global matches, there are many possible false matches between any two images. Here, we use optical imaging data of binocular disparity response in the visual cortex of awake and anesthetized monkeys to demonstrate that the second visual cortical area (V2) is the first cortical stage that correctly discards false matches and robustly encodes correct matches. Our findings indicate that a key transformation for achieving depth perception lies in early stages of extrastriate visual cortex and is achieved by population coding.


  • ?1To whom correspondence should be addressed. Email: dr_gangchen{at}zju.edu.cn.

This is an open access article distributed under the PNAS license.

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