Cortical modification of an epileptogenic focus.

The influence of cerebral cortex on penicillin-induced spikes in striate cortex was studied with the technique of hypothermic block. Direct cooling of the involved or contralateral striate cortex markedly reduced seizure activity. Significant reduction in seizure activity was also seen with cooling of ipsilateral and contralateral visual association cortex. None of the other cortical areas tested had a reproducible effect on the frequency of seizures. These findings are discussed in term of local and remote factors influencing the epileptogenic focus.