The fovea is essential for peripheral vision: The effect of foveal distractors on extra-foveal perception

Abstract

Neuroimaging evidence indicates that visual information about objects in the periphery is fed back to foveal retinotopic cortex in a new and separate representation. Additionally, delayed disruption of foveal confluence via transcranical magnetic stimulation impairs discrimination of objects in the periphery, suggesting this feedback mechanism is essential for extra-foveal perception. In this study, we developed a behavioural paradigm to further explore the nature of this feedback mechanism and provide a behavioural measure. Participants performed a discrimination task on objects in the periphery while fixating centrally. A visual distractor presented at the fovea 100ms after presentation of the peripheral stimulus disrupted perceptual discrimination more than visual distractors presented at other stimulus onset asynchronies (SOAs). In a control experiment, a visual distractor presented elsewhere in the periphery at the same SOAs did not impair behavioural performance. These results corroborate previous research showing foveal retinotopic cortex is essential for extra-foveal perception. This study also demonstrates a new paradigm for investigating the nature of the foveal feedback phenomenon.

Meeting abstract presented at VSS 2015