[Complex characteristics of an epileptogenic focus in intracerebral space-occupying processes according to the findings of electrocorticography, polarographic studies and electron microscopy].

The work discusses the results of a study of the overall electric activity of the cerebral cortex, its frequency analysis and integration in brain tumors attended with epileptic seizures. The changes in electric activity are correlated with the cortical ultrastructure and the oxygen balance in the brain tissue. The possible mechanisms responsible for the development, cessation or absence of epileptic seizures in the clinical picture of brain tumors are analysed. Data are presented in evidence of the important role of hypoxia of various degrees in these mechanisms. It is established that activation of the synaptic apparatus may be considered as an ultrastructural correlator of hyperexcitation in the epileptic focus.