Abstract
A previous study showed a novel form of feedback in the visual system – foveal retinotopic cortex conveys information about stimuli presented in the periphery (Williams et al., 2008). However, the behavioral relevance of this feedback representation remains unclear – does it provide a benefit to processing of the peripheral stimuli? To address this question, we measured subjects’ visual discrimination performance in the periphery while interrupting foveal representation. During each trial, subjects reported the orientation of a grating (left-tilted or right-tilted) briefly presented in a peripheral location while fixating at the center. At the same time, another grating with the same orientation as, or different orientation from, the peripheral target grating was briefly presented at the fovea and masked (to render it invisible). When the foveal grating’s orientation differed from that of the peripheral grating, subjects showed impaired visual discrimination in the periphery, compared with when the two gratings’ orientation matched each other. This occurred even though subjects did not consciously perceive the foveal grating. These results indicate that interrupting foveal feedback information can impair our ability to discriminate peripheral visual stimuli, suggesting functional significance of foveal feedback representation.
Meeting abstract presented at VSS 2012