[Post-synaptic responses of cat visual cortex neurons to stimulation of the lateral geniculate body]

Intracellular responses of 50 neurons in the striate cortex to lateral geniculate body stimulation were studied in cats immobilized with d-tubocurarine. Activation without subsequent inhibition was determined in 22 per cent of the cells. Initial activation was followed by inhibition in 32 per cent of the cells and primary inhibition was found in 46 per cent of the cells. The difference between the shortest latencies of IPSP and EPSP was 0.9 ms. A conclusion is made that in the striate cortex there exists a mechanism of afferent inhibition. The neurons responding with primary activation may play the role of inhibitory cells in such inhibition.