Top-down feedback controls spatial summation and response amplitude in primate visual cortex.

ABSTRACT: Sensory information travels along feedforward connections through a hierarchy of cortical areas, which, in turn, send feedback connections to lower-order areas. Feedback has been implicated in attention, expectation, and sensory context, but the mechanisms underlying these diverse feedback functions are unknown. Using specific optogenetic inactivation of feedback connections from the secondary visual area (V2), we show how feedback affects neural responses in the primate primary visual cortex (V1). Reducing feedback activity increases V1 cells' receptive field (RF) size, decreases their responses to stimuli confined to the RF, and increases their responses to stimuli extending into the proximal surround, therefore reducing surround suppression. Moreover, stronger reduction of V2 feedback a

SUBMITTER: Nurminen L 

PROVIDER: S-EPMC5995810 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature