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bioRxiv · 10.1101/2023.02.08.527666

Out of sight, out of mind: Responses in primate ventral visual cortex track individual fixations during natural vision

Abstract

During natural vision, primates shift their gaze several times per second with large, ballistic eye movements known as saccades. Open questions remain as to whether visual neurons retain their classical retinotopic response properties during natural vision or whether neurons integrate information across fixations and predict the consequences of impending saccades. Answers are especially wanting for vision in complex scenes relevant to natural behavior. We let 13 monkeys freely view thousands of large natural images, recorded over 883 hours of neuronal responses throughout the ventral visual pathway across 4.7 million fixations, and designed flexible analyses to reveal the spatial, temporal, and feature selectivity of the responses. Ventral visual responses followed each fixation and did not become gaze-invariant as monkeys examined an image over seconds. Computational models revealed that neuronal responses corresponded to eye-centered receptive fields. The results suggest that ventral visual cortex remains predominantly retinotopic during natural vision and does not establish a gaze-independent representation of the world.

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Xiao, W., Sharma, S., Kreiman, G., Livignstone, M.. 2023-02-09. Out of sight, out of mind: Responses in primate ventral visual cortex track individual fixations during natural vision. https://doi.org/10.1101/2023.02.08.527666

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