Relationship between response latency and amplitude for ganglion and geniculate X- and Y-cells in the cat

This study investigates the relationship between visual response latency and amplitude in the retina and dorsal lateral geniculate nucleus (dLGN) of the anesthetized, paralyzed cat. The discharge rate profiles of retinal ganglion and dLGN X- and Y-cells were measured on a trial by trial basis during repeated stimulation with sinusoidal grating patterns. Latencies of response onsets and peaks were regressed linearly against different measures of response amplitude to determine the extent of covariance. In general, response amplitude was a poor predictor of response latency for both retinal ganglion and geniculate cells. The results suggest that response latency, which changes systematically with stimulus spatial frequency and/or contrast, is not a trivial consequence of discharge rate at either level of the visual system.