Specialized contributions of mid-tier stages of dorsal and ventral pathways to stereoscopic processing in macaque
Abstract
The division of labor between the dorsal and ventral visual pathways has been well studied, but not often with direct comparison at the single-neuron resolution with matched stimuli. Here we directly compared how single neurons in MT and V4, mid-tier areas of the two pathways, process binocular disparity, a powerful cue for 3D perception and actions. We found that MT neurons transmitted disparity signals more quickly and robustly, whereas V4 or its upstream neurons transformed the signals into sophisticated representations more prominently. Therefore, signaling speed and robustness were traded for transformation between the dorsal and ventral pathways. The key factor in this tradeoff was disparity-tuning shape: V4 neurons had more even-symmetric tuning than MT neurons. Moreover, the tuning symmetry predicted the degree of signal transformation across neurons similarly within each area, implying a general role of tuning symmetry in the stereoscopic processing by the two pathways.
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Author details
Funding
Ministry of Education, Culture, Sports, Science and Technology (2324007)
- Ichiro Fujita
Ministry of Education, Culture, Sports, Science and Technology (15H01437)
- Ichiro Fujita
Ministry of Education, Culture, Sports, Science and Technology (17H01381)
- Ichiro Fujita
Ministry of Education, Culture, Sports, Science and Technology (18H05007)
- Ichiro Fujita
Ministry of Internal Affairs and Communications
- Ichiro Fujita
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All experimental procedures in this study were approved by the Animal Experiment Committee (Permit Numbers: FBS-12-016, FBS-13-003-1) of Osaka University, and conformed to the Guide for the Care and Use of Laboratory Animals issued by the National Institutes of Health, USA.
Copyright
© 2021, Yoshioka 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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