Single unit recordings were made from cat optic tract fibers while varying the luminance and size of spots placed in the center of a cell's receptive field. Both transient and steady state stimulus-response curves could be divided into two segments: a monotonic increasing portion for low contrast levels and a non-monotonic decreasing segment for high contrast levels. Three conclusions were made: 1. (1) that the cat retinal ganglion cell gives a more precise representation of intensity changes in the low contrast range than in the high contrast range; 2. (2) that the intensity code is non-linear for the low contrast range; 3. (3) that more information about intensity changes is signalled during the transient phase than during the steady state phase of the response.
ASJC Scopus subject areas
- Sensory Systems