This study was designed to determine if the K-Complex reflects an arousal f
rom sleep or a sleep protection mechanism. Ten participants were presented
auditory stimuli every 20 s while asleep. Trials were sorted according to t
he presence or absence of a K-Complex. A fast Fourier Transformation of the
data was computed on EEC; segments prior to and following stimulus onset.
The log power of activity in delta, theta, alpha, sigma, and beta bandwidth
s was computed. When a K-Complex was elicited, there were no differences in
EEG activity prior to and following the stimulus. However, during slow wav
e sleep, when a K-Complex was not elicited, there was a significant overall
increase in theta, alpha, sigma, and beta activity following stimulus. The
se results tend to support the notion that the K-Complex appears to prevent
arousal.