Processing of motion-boundary orientation in macaque V2
Human and non-human primates are good at identifying an object based on its motion, a task that is believed to be carried out by the ventral visual pathway. However, the neural mechanisms underlying such ability remains unclear. We trained macaque monkeys to do orientation discrimination for motion-boundaries (MB) and recorded neuronal response in area V2 with microelectrode arrays. We found 10.9% of V2 neurons exhibited robust orientation-selectivity to MBs, and their responses correlated with monkeys' orientation-discrimination performances. Furthermore, the responses of V2 direction-selective neurons recorded at the same time showed correlated activity with MB neurons for particular MB stimuli, suggesting that these motion-sensitive neurons made specific functional contributions to MB discrimination tasks. Our findings support the view that V2 plays a critical role in MB analysis and may achieve this through a neural circuit within area V2.
Data and codes are available in Mendeley dataset.http://dx.doi.org/10.17632/fjy37kc8pd.3
Processing of motion-boundary orientation in macaque V2Mendeley Data, DOI 10.17632/fjy37kc8pd.3.
Article and author information
National Natural Science Foundation of China (31530029)
- Haidong D Lu
National Natural Science Foundation of China (31625012)
- Haidong D Lu
National Natural Science Foundation of China (31371111)
- Haidong D Lu
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Animal experimentation: Four hemispheres from two adult male macaque monkeys (Macaca mulatta) were used in this study. All procedures were performed in accordance with the National Institutes of Health Guidelines and were approved by the Institutional Animal Care and Use Committee of the Beijing Normal University (protocol number: IACUC(BNU)-NKCNL2013-13).
- Kristine Krug, University of Oxford, United Kingdom
- Received: July 22, 2020
- Accepted: March 24, 2021
- Accepted Manuscript published: March 24, 2021 (version 1)
- Version of Record published: April 7, 2021 (version 2)
- Version of Record updated: April 13, 2021 (version 3)
© 2021, Ma et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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