Nicole C Rust

Wednesday 7th February 2018

Time: 4.00pm

Ground Floor Seminar Room

25 Howland Street, London, W1T 4JG

Beyond identification: how your brain signals whether you’ve seen it before

Our visual memory percepts of whether we have encountered specific objects or scenes before are hypothesized to manifest as decrements in neural responses in inferotemporal cortex (IT) with stimulus repetition. To evaluate this proposal, we recorded IT neural responses as two monkeys performed a single-exposure visual memory task designed to measure the rates of forgetting with time. We found that a weighted linear read-out of IT was a better predictor of the monkeys’ forgetting rates and reaction time patterns than a strict instantiation of the repetition suppression hypothesis, expressed as a total spike count scheme. Behavioral predictions could be attributed to visual memory signals that were reflected as repetition suppression and were intermingled with visual selectivity, but only when combined across the most sensitive neurons.

Bio:

Nicole Rust is an Associate Professor in the Department of Psychology and a member of the Computational Neuroscience Initiative at the University of Pennsylvania. She received her Ph.D. in neuroscience from New York University, and trained as a postdoctoral researcher at Massachusetts Institute of Technology before joining the faculty at Penn in 2009. Research in her laboratory is focused on understanding the neural basis of visual memory, including how we remember the objects and scenes that we have encountered, even after viewing thousands, each only for few seconds. To understand visual memory, her lab employs a number of different approaches, including investigations of human and animal visual memory behaviors, measurements and manipulations of neural activity, and computational modeling. She has received a number of awards for both research and teaching including a McKnight Scholar award, an NSF CAREER award, a Alfred P. Sloan Fellowship, and the Charles Ludwig Distinguished teaching award. Her research is currently funded by the National Eye Institute at the National Institutes of Health, the National Science Foundation, and the Simons Collaboration on the Global Brain.