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Russell De Valois Memorial Lecture Series

We hope you can join us for our upcoming Russell De Valois Memorial Lecture on Thursday June 1, 2017 (4pm in 489 Minor) with Dr. William T. Newsome.

The Russell De Valois Memorial Lectures series commemorates our beloved friend and colleague Russell De Valois, who pioneered the systematic analysis of color and spatial vision while he was a faculty member at UC Berkeley. Established in 2005, this lecture series brings outstanding vision scientists to the Berkeley campus to discuss their recent research. The series is funded by generous contributions to the School of Optometry in memory of Professor De Valois.


Thursday, June 1, 2017 at 4:00pm – 5:00pm in 489 Minor Hall. Reception to follow.


Monitoring Covert Visual Decisions via Neural Population Dynamics in Frontal Cortex

Presented by

William T. Newsome, PhD
Harman Family Provostial Professor
Vincent V.C. Woo Director of the Stanford Neurosciences Institute
Professor of Neurobiology and, by courtesy, of Psychology


The neural mechanisms underlying visual decisions are typically examined by statistical analysis of large numbers of trials from sequentially recorded single neurons. Averaging across sequential recordings, however, obscures important aspects of decision-making such as ‘changes of mind’ (CoM) that occur at variable times on different trials. I will show that the covert decision variables (DV) can be tracked dynamically on single behavioral trials via simultaneous recording of large neural populations in prefrontal cortex. Vacillations of the visual DV, in turn, identify candidate CoM in monkeys, and show that they closely match the known properties of human CoM. Thus simultaneous population recordings can provide insight into transient, internal cognitive states that are otherwise undetectable.