Contribution of linear spatiotemporal receptive field structure to velocity selectivity of simple cells in area 17 of cat.
We have examined the spatiotemporal structure of simple receptive fields in the cat's striate cortex by cross-correlating their spike trains with an ensemble of stimuli consisting of stationary bright and dark spots whose position was randomized on each 50 msec frame. Receptive fields were found to be either separable or inseparable in space-time and responses to moving stimuli were predicted from the spatiotemporal structure of the cell under study. Most simple cells with separable spatiotemporal receptive fields were not direction selective. All simple cells with inseparable spatiotemporal receptive fields were found to prefer movement in one direction. The optimal speed and direction were estimable from the slope of individual subregions observed in the space-time plane. The results are consistent with a linear model for direction selectivity.
McLean
J
J
David Mahoney Institute of Neurological Sciences, School of Medicine, University of Pennsylvania, Philadelphia 19104.
Palmer
L A
LA
D000818:Animals; D002415:Cats; D009039:Motion Perception / Q000502:physiology*; D009474:Neurons / Q000502:physiology; D010775:Photic Stimulation; D014793:Visual Cortex / Q000166:cytology / Q000502:physiology*; D014796:Visual Perception / Q000502:physiology*