Slow wave activity and slow oscillations in sleepwalkers and controls: effects of 38 h of sleep deprivation

Summary Sleepwalkers have been shown to have an unusually high number of arousals from slow wave sleep and lower slow wave activity ( SWA ) power during the night than controls. Because sleep deprivation increases the frequency of slow wave sleep ( SWS ) arousals in sleepwalkers, it may also affect the expression of the homeostatic process to a greater extent than shown previously. We thus investigated SWA power as well as slow wave oscillation ( SWO ) density in 10 sleepwalkers and nine controls at baseline and following 38 h of sleep deprivation. There was a significant increase in SWA during participants' recovery sleep, especially during their second non‐rapid eye movement ( NREM ) period. SWO density was similarly increased during recovery sleep's first two NREM periods. A fronto‐central gradient in SWA and SWO was also present on both nights. However, no group differences were noted on any of the 2 nights on SWA or SWO . This unexpected result may be related to the heterogeneity of sleepwalkers as a population, as well as our small sample size. SWA pressure after extended sleep deprivation may also result in a ceiling effect in both sleepwalkers and controls.