A certain dynamics of changes in intrahemisphere contrast was revealed in the process of development of the transcallosal response: in the beginning of the response the right hemisphere is more focal, then the left one and afterwards again the right hemisphere. In males, the main changes of focality are related to the left hemisphere whereas in females--to the right one. The focality of a greater value is characteristic of the males' transcallosal responses whereas the distribution of the EPs is more diffuse in females. A specifics of the contrast gradient dynamics is described for the projection and associative cortical areas. A zonal specifics of the intrahemisphere contrast was shown in animals of different sex.