Clinical response to sleep deprivation and auditory-evoked potentials--preliminary results

The biological substrate of the antidepressant effect of total sleep deprivation (TSD) has not yet been elucidated. Furthermore, electrophysiological predictors for the response to TSD have not been studied extensively. The aim of present study was to examine the changes in acoustically evoked potentials (N1, P2, N2, P300) after a night of sleep deprivation and to analyze differences between responders and nonresponders. 17 depressive inpatients were studied. The most prominent changes in auditory evoked potentials (responders and nonresponders) were found for the amplitude of the P300 component. Differences between responders and nonresponders could be established for the amplitude and latencies in the N1 component. Responders showed smaller N1 amplitudes before TSD but a higher increase after TSD than nonresponders.