Suppressing feedback signals to visual cortex abolishes attentional modulation

• DOI: 10.1126/science.ade1855
• Publication Date: 2023-02-02T18:58:31Z
• Authors: Samantha R. Debes; Valentin Dragoi
• Keywords: Feed forward; Sensory cortex

Attention improves perception by enhancing the neural encoding of sensory information. A long-standing hypothesis is that cortical feedback projections carry top-down signals to influence coding. However, this has never been tested establish causal links. We used viral tools label connections from area V4 targeting early visual cortex (area V1). While monkeys performed a visual-spatial attention task, inactivating axonal terminals in V1 without altering local intracortical and feedforward inputs reduced response gain single cells impaired accuracy populations for external stimuli. These effects are primarily manifested superficial layers propagate downstream V4. enhances coding across specifically strength corticocortical layer-dependent manner.