Title: Assembly of receptive fields in cat visual cortex
Speaker: Professor D. Ferster
Speaker Info: Northwestern U.
The neurons of the visual cortex are remarkably sensitive to detailed properties of image elements. They will not respond unless stimulus has the correct orientation, direction of motion, depth and size. Yet the thalamic neurons that provide information about the visual image to the cortex are insensitive to these parameters, responding to almost any change in image contrast. Currently, there are two competing models for how cortical selectivity arises. One relies on feed-forward connections from the thalamus to the cortex that act as linear filters. The other relies on feedback connections that selectively amplify the thalamic inputs nonlinearly. I will outline these models and present some of the data from our lab that bear on them.Date: Friday, April 23, 1999