Event-Related Potentials During the Wake/Sleep Transition In Adults With and Without Primary Insomnia

Date of Award


Degree Type


Degree Name

Doctor of Philosophy (PhD)



First Advisor

John Harsh

Advisor Department



This study examined auditory event-related potentials (ERPs) during wake, sleep, and the wake-sleep transition in good sleepers and insomniacs. Subjects were instructed to attend to an infrequently presented stimulus (target) and to ignore a more frequently presented (non-target) stimulus. Differences in parietal P300 amplitude were found during wakefulness, with P300 amplitude larger for the Insomnia Group immediately prior to lights out. By Stage 1 and throughout Stage 2 sleep, the parietal positivity identified as P300 was absent and the morphology of the event-related potential (ERP) waveform changed from a prominent parietal positivity in wakefulness to a prominent central negativity (N350) during sleep. During Stage 2b sleep, N350 amplitude (a component of the sleep ERP) was significantly lower for the Insomnia Group than the Good Sleep Group. The findings suggest decreased inhibition of cortical activation/arousal in the Insomnia Group, increased inhibition of cortical activation/arousal in the Good Sleep Group, or some combination of these.