Abstract: | The results are outlined of a comparative estimation of averaged EP recorded in response to simultaneous and separate presentation of photic and acoustic stimuli on EEG of fifteen healthy subjects and twelve patients with focal lesions of the diencephalic structures. Investigation of the EP components and integral-temporal parameters has revealed that in healthy subjects EP to a combined heteromodal stimulation considerably exceeded by amplitude the one recorded in response to a separate presentation of stimuli. In case of lesion of the diencephalic formations, the converging effect of polysensory stimulation for the main waves of the response was less pronounced than in healthy subjects. At the same time, in pathological cases the summation effect of the afteraction potential (recorded after the main EP components as a slow negative oscillation) was manifested most distinctly, especially in the central zone of the cortex. |