Dynamic propagation of seizure discharges in the motor cortical kindling

Applying a multidimensional autoregressive model to an ictal discharge, a dynamic propagation of seizure discharge was investigated in cats kindled by motor cortical stimulations. By means of this method, the reactive discharge peculiar to each brain structure and projected activity could be separately described in terms of a new measure, i.e., power contribution which defines a degree of participation of each reactive activity in discharges at a given brain structure. The results showed that six phases could be distinguished during the process of generalization and that electrically induced discharge on the motor cortex might propagate as follows, first, a system including the ventral nuclei of the thalamus and perhaps the caudate nucleus are involved. After participation of more dorsal systems within homolateral brain structures, contralateral structures begin to participate in the generation of seizure discharges and finally become dominant in the maturated seizure.