[Changes in evoked slow cerebral potential (contingent-negative variation) in epilepsy]

Contingent negative variation (CNV) was examined in 14 epileptic patients (5 with generalized and 9 with partial fits) both before and after 24 hours of sleep deprivation. Background CNV indices differed significantly by higher amplitudes of nearly all CNV components from the ones of healthy individuals. Amplitudes of postimperative negative waves (PINW) and general waves differed most of all. After sleep deprivation there was an PINW increase as well as the tendency to the late CNV component amplitude's increase. Elevation of CNV amplitudes after sleep deprivation was more pronounced in patients in which the deprivation provoked development of epileptic fits in comparison with patients which endured sleep deprivation rather favourably. The changes revealed in CNV components of the patients with epilepsy were considered in terms of disorders in regulatory mechanisms at the level of apical dendrites of cortical neurons' excitation.