[Layer-by-layer analysis of transcallosal responses in the cat sensomotor cortex]

Transcallosal responses to stimulation of the cortex at the depth of 0.5 mm had the least phase I and the greatest phase II as compared with their values at a deeper stimulation. The maximal phase II occurred at the 1 mm stimulation. At a fixed depth of stimulation the maximal amplitude of the phase I coincided with the depth of stimulation. At 1 and 2 mm stimulations, the second maximum of the responses occurred at the depth of 2 and 1 mm, resp. The data obtained suggest that the callosal connections are organized in a "layer--to--layer" way, and that there are some cross--connections between the layers III and V ("one layer--another layer").