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V1 neurons respond differently to object motion versus motion from eye movements.

ABSTRACT: How does the visual system differentiate self-generated motion from motion in the external world? Humans can discern object motion from identical retinal image displacements induced by eye movements, but the brain mechanisms underlying this ability are unknown. Here we exploit the frequent production of microsaccades during ocular fixation in the primate to compare primary visual cortical responses to self-generated motion (real microsaccades) versus motion in the external world (object motion mimicking microsaccades). Real and simulated microsaccades were randomly interleaved in the same viewing condition, thereby producing equivalent oculomotor and behavioural engagement. Our results show that real microsaccades generate biphasic neural responses, consisting of a rapid increase in the firing rate followed by a slow and smaller-amplitude suppression that drops below baseline. Simulated microsaccades generate solely excitatory responses. These findings indicate that V1 neurons can respond differently to internally and externally generated motion, and expand V1's potential role in information processing and visual stability during eye movements.

SUBMITTER: Troncoso XG

PROVIDER: S-EPMC4579399 | biostudies-literature | 2015 Sep

REPOSITORIES: biostudies-literature

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V1 neurons respond differently to object motion versus motion from eye movements.

Troncoso Xoana G XG McCamy Michael B MB Jazi Ali Najafian AN Cui Jie J Otero-Millan Jorge J Macknik Stephen L SL Costela Francisco M FM Martinez-Conde Susana S

Nature communications 20150915

How does the visual system differentiate self-generated motion from motion in the external world? Humans can discern object motion from identical retinal image displacements induced by eye movements, but the brain mechanisms underlying this ability are unknown. Here we exploit the frequent production of microsaccades during ocular fixation in the primate to compare primary visual cortical responses to self-generated motion (real microsaccades) versus motion in the external world (object motion m ...[more]

PMID: 26370518

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Dataset Information

V1 neurons respond differently to object motion versus motion from eye movements.

Publications

V1 neurons respond differently to object motion versus motion from eye movements.

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