Comparative characteristics of spatial hearing of patients with different forms of cortical epilepsy

Perception of signals modeling directed movement of a sound source by three groups of patients with (1) temporal epilepsy, (2) epileptic foci in the frontal region, and (3) the epileptic syndrome due to local organic lesions in the temporal or frontal lobes was studied. It was established that the features and degree of spatial (binaural) hearing disorders in temporal epilepsy were determined not only by the localization and the extent of a lesion in the temporal lobe, but also by the areas beyond it that were involved in the epileptic process. Patients with organic lesions (tumors, cysts) involving the temporal lobe cortex may reveal more severe spatial hearing disorders than temporal epilepsy patients with the same localization of the foci of convulsive activity. A relatively isolated lesion of the frontal region cortex does not influence the assessment of the parameters of moving sound signals used. Possible neurophysiological mechanisms underlying the found spatial hearing disorders as well as the possibility of using the results obtained to solve the problems of differential diagnosis are considered.