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A Causal Role for the Cortical Frontal Eye Fields in Microsaccade Deployment.

ABSTRACT: Microsaccades aid vision by helping to strategically sample visual scenes. Despite the importance of these small eye movements, no cortical area has ever been implicated in their generation. Here, we used unilateral and bilateral reversible inactivation of the frontal eye fields (FEF) to identify a cortical drive for microsaccades. Unexpectedly, FEF inactivation altered microsaccade metrics and kinematics. Such inactivation also impaired microsaccade deployment following peripheral cue onset, regardless of cue side or inactivation configuration. Our results demonstrate that the FEF provides critical top-down drive for microsaccade generation, particularly during the recovery of microsaccades after disruption by sensory transients. Our results constitute the first direct evidence, to our knowledge, for the contribution of any cortical area to microsaccade generation, and they provide a possible substrate for how cognitive processes can influence the strategic deployment of microsaccades.

SUBMITTER: Peel TR

PROVIDER: S-EPMC4980061 | biostudies-literature | 2016 Aug

REPOSITORIES: biostudies-literature

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A Causal Role for the Cortical Frontal Eye Fields in Microsaccade Deployment.

Peel Tyler R TR Hafed Ziad M ZM Dash Suryadeep S Lomber Stephen G SG Corneil Brian D BD

PLoS biology 20160810 8

Microsaccades aid vision by helping to strategically sample visual scenes. Despite the importance of these small eye movements, no cortical area has ever been implicated in their generation. Here, we used unilateral and bilateral reversible inactivation of the frontal eye fields (FEF) to identify a cortical drive for microsaccades. Unexpectedly, FEF inactivation altered microsaccade metrics and kinematics. Such inactivation also impaired microsaccade deployment following peripheral cue onset, re ...[more]

PMID: 27509130

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