Where do correlations between neuronal activity and sensory decisions originate?
Dr. Bruce Cumming (National Institutes of Health) Venue: Room 218, Henry Wellcome Building Date: 6th April 2009 Time: 10:00 – 11:00 Simultaneous use of single unit recording and threshold psychophysics has revealed correlations between perceptual choice and firing rate, that cannot be explained by the visual stimulus (Choice Probability, CP). Quantitative modeling studies have explained the observed magnitudes with a bottom-up scheme, in which CP reflect an effect of random fluctuations in firing rate upon choice. In order to test this interpretation further, we measured CP using a stimulus which simultaneously allowed the use of white noise analysis to infer how fluctuations in the stimulus content affected (1) neuronal activity and (2) psychophysical choices. Two monkeys performed a disparity identification task while we recorded the activity of disparity selective neurons in V2. The stimulus was a random dot stereogram in which the disparity was chosen at random (from a discrete dis
