[Spatial organization of the interaction between transcallosal and thalamocortical flows of excitation]

In 10 immobilized cats, the interaction between transcallosal potentials and responses to stimulation of the n. ischiadicus was studied in 85 points of the sensomotor cortex. The interaction effect of these responses is determined by their configuration in a given point as well as by time interval between them. The interaction has an obvious spatial-temporal character. Facilitating influences localized mainly in the area of overlapping of EP focuses whereas peripheral areas of the cortex were under a greater depressing effect of the transcallosal flow. The intermediate areas were subject alternately to facilitating and depressing influences. The above effects of interaction seem to reveal a modulating function of transcallosal flow which actualizes the concentration and contrasting of the excitation spreading over ascending projections.