Psychoacoustics and Neurophysiological Alterations after 30-36 Hours of Sleep Deprivation.

BACKGROUND AND AIM: Sleep deprivation (SD) may result in perceptual and cognitive alterations in healthy subjects. Our objective was to compare whether psychoacoustics and neurophysiological variables in healthy subjects were altered after SD of 30-36 h.

METHOD: We examined 22 subjects by means of several psychoacoustics tests, P300 and mismatch negativity (MMN) recordings, and brainstem auditory evoked potentials (BAEP) before and after 30-36 h of SD.

RESULTS: In the psychoacoustics tests, we found that after SD, difficulties were experienced by the left ear in the discrimination of words in noise and by the right ear in music discrimination. In the neurophysiological tests, we found delayed latencies of P300 and MMN wave; there was a delay of wave I in both ears, and wave V in the right ear in BAEP. We found significant correlations with positive direction between P300 latency and words in noise and music discrimination in the right ear.

CONCLUSIONS: SD results in alterations of central auditory processing perception and delays of brain neurophysiological responses, with some correlations between the psychoacoustics and neurophysiological tests. These alterations may relate to other cognitive alterations that deserve more research in future studies.