Experimental Investigation

Auditory Evoked Potentials in Sleep

  • Sibel KOCAASLAN
  • Adile ÖNIZ
  • Murat ÖZGÖREN

Received Date: 29.12.2009 Accepted Date: 26.04.2010 Meandros Med Dent J 2010;11(3):49-56

OBJECTIVE:

The aim of the present study is to investigate the responses to auditory stimulations during different sleep stages.

MATERIALS and METHODS:

Twelve subjects (mean age: 24.5±4.1; 2 female) participated in the study. Data collection was performed with 40 channel NuAmps [Electroencephalography (EEG), electrooculography (EOG), chin electromyography (EMG)] recording system, auditory stimulation unit, video and Bispectral Index (BIS) monitorization. The records were scored according to Rechtschaffen and Kales (R&K) scoring system. Auditory evoked potentials (AEP) were analyzed in each sleep stage [Non-REM (N1, N2, N3 and N4) and REM]. N100, P200, N300, P450, N550 and P900 (P750) components were examined in Cz electrode. One-wayANOVA was applied to compare amplitudes and latencies of AEP components in different sleep stages. Post-hoc comparisons were conducted with Bonferroni method.

RESULTS:

The results showed that by deepening of sleep N100 decreased, N300 and P900 increased. The changes and interactions in the waveforms pointed at a dynamic information processing in the brain throughout different stages (and also microstates) of sleep.

CONCLUSION:

The auditory stimulations serve as a plausible study method providing a scope for brain functioning from early sensory potentials to very late processes (as late as 900 ms post-stimulus). These electrophysiological hints may be utilized for future sleep research studies as well as clinical applications.

Keywords: Sleep, auditory evoked potentials, electroencephalography, cognitive information processing, P900