May 26, 2017 -
3:15pm to 4:30pm
Jordan Hall (Building 420), Room 050
A common neural basis of contrast and motion coherence perception in human visual cortex
Contrast and coherence are two fundamental visual attributes that control the visibility of motion in random dot displays. Past studies of the perception of these attributes in humans have examined only a few specific cortical regions and have used manipulations in which both contrast and motion coherence changed simultaneously. We independently varied the contrast and coherence of random-dot displays while measuring changes in the BOLD response. Using that data we fit an estimate of the underlying neural response functions across visual cortex and find that sensitivity to each feature varies systematically across cortical regions. To test whether these neural responses might be sufficient to account for human perception we used our model to make predictions about human performance in a perceptual discrimination task. Comparing these predictions to data from human observers suggests a common neural basis for contrast and motion coherence where each feature is read out for perception in a similar manner, but from distinct cortical regions.
Department of Psychology