| Literature DB >> 25568118 |
Golbarg T Saber1, Franco Pestilli2, Clayton E Curtis3.
Abstract
Saccade planning may invoke spatially-specific feedback signals that bias early visual activity in favor of top-down goals. We tested this hypothesis by measuring cortical activity at the early stages of the dorsal and ventral visual processing streams. Human subjects maintained saccade plans to (prosaccade) or away (antisaccade) from a spatial location over long memory-delays. Results show that cortical activity persists in early visual cortex at the retinotopic location of upcoming saccade goals. Topographically specific activity persists as early as V1, and activity increases along both dorsal (V3A/B, IPS0) and ventral (hV4, VO1) visual areas. Importantly, activity persists when saccade goals are available only via working memory and when visual targets and saccade goals are spatially disassociated. We conclude that top-down signals elicit retinotopically specific activity in visual cortex both in the dorsal and ventral streams. Such activity may underlie mechanisms that prioritize locations of task-relevant objects.Entities:
Keywords: antisaccade; fMRI; retinotopy; saccade; spatial cognition; working memory
Mesh:
Year: 2015 PMID: 25568118 PMCID: PMC4287145 DOI: 10.1523/JNEUROSCI.1687-14.2015
Source DB: PubMed Journal: J Neurosci ISSN: 0270-6474 Impact factor: 6.167