Non Rapid Eye Movement (NREM) sleep parasomnias (sleepwalking and sleep terrors) are frequent
and disabling sleep disorders characterized by arousal specifically from slow wave sleep
(SWS) with dissociated brain activity that may be related to lower nociceptive state. The
investigators recently reported frequent subjective complaints of chronic pain, migraine and
headache during wakefulness in adult sleepwalkers. They also described frequent analgesia
during severe and injuring episodes, suggesting a relationship between dissociated brain
activity and nociceptive dysregulation. However, this study did not included objective
nociceptive measures and the retrospective assessment of perceived pain during parasomnia
episodes over a lifetime span might also introduce a recall bias.
The aims of the present study are to measure objective pain sensitivity in patients with NREM
parasomnias and matched controls during 1) parasomniac episodes, 2) light NREM sleep and SWS,
and 3) wakefulness.
Fifteen adults with severe NREM parasomnia and 15 age and sex-matched controls will be
recruited. A 25 hours (8 AM to 9 AM) sleep deprivation protocol followed by auditory
stimulations during SWS will be used to trigger parasomniac episodes. Thermoalgic
stimulations of graduate intensity will be applied during wakefulness (8 PM) to determine the
nociceptive threshold. During the recovery sleep following the sleep deprivation, the
investigators will apply repeated subthreshold thermoalgic stimulations in NREM stage 2, SWS
and triggered parasomniac episodes and report the behavioural/neurophysiologic nociceptive
The investigators hypothesized a lower nociceptive threshold during wakefulness in
sleepwalkers and a decrease of the arousabiliy during SWS and parasomniac episodes. This
study may help to better understand the etiology and mechanisms underlying the clinical
enigma of the nociceptive dysregulation in NREM sleep parasomnias.