Lily Turkstra

Presentation Title

Neural Correlates of Visual Working Memory in Early Visual Cortex of a Blind Human.

Abstract

Visual working memory (VWM) has been studied extensively across the cortices of primates and humans, yet the contribution of spiking activity in human early visual cortex (EVC) remains unclear. Along with their central goal of restoring useful vision to blind individuals, cortical visual prostheses (CVP) offer a unique platform to explore such neuroscientific theories. Our research leverages the bidirectional capabilities of a CVP implanted in EVC of a blind individual to electrically evoke visual percepts while simultaneously recording spiking activity. The participant performed a 3 percept delayed matching task, reporting whether one percept matched a second percept after a 5 second delay. A behavioral accuracy of 90% was achieved across 450 trials, and patterns of recorded spiking activity were significantly different across each task period. Each remembered visual percept was uniquely encoded in the local spiking activity during the delay period with a decoding accuracy significantly above chance. Our results highlight, for the first time, the role of spiking EVC activity in maintaining information over delay periods, and may aid in improving prosthesis integration with ongoing essential cognitive processes.