Contribution of brainstem circuits in pathophysiology of NREM-sleep parasomnias

Neurosci Lett. 2021 Aug 24:760:136075. doi: 10.1016/j.neulet.2021.136075. Epub 2021 Jun 18.

Abstract

Objective: We aimed to investigate the brainstem circuits to reveal if there was any abnormality in these circuits in clinically diagnosed patients with NREM parasomnias during wakefulness.

Methods: Twelve patients with NREM-sleep parasomnia diagnosed according to ICSD-3 criteria and a control group of 16 healthy subjects were enrolled into our study. We analyzed the auditory startle reflex (ASR), blink reflex (BR), prepulse inhibition (PPI) of BR and recovery excitability of BR.

Results: There was a trend for longer responses from orbicularis oculi and sternocleidomastoid muscles after auditory stimulation in the patients compared to those in the healthy subjects. The recovery percentages at 200 ms and 300 ms showed a borderline significance in the patients. No significant difference was found in the R2-PPI between the patients and healthy subjects.

Conclusions: Our results suggest a mildly enhanced ASR and relatively early facilitation of BR excitability in patients with NREM-sleep parasomnia during daytime. Although our findings suggest involvement of brainstem networks in NREM-sleep parasomnia during wakefulness, it would be better to study these networks at night and during daytime to see if there is any contribution.

Keywords: Auditory startle reflex; Blink reflex recovery excitability; NREM-sleep parasomnia; Prepulse inhibition of blink reflex.

Publication types

  • Observational Study

MeSH terms

  • Adult
  • Blinking / physiology
  • Brain Stem / physiopathology*
  • Case-Control Studies
  • Electroencephalography
  • Female
  • Healthy Volunteers
  • Humans
  • Male
  • Nerve Net / physiology
  • Parasomnias / diagnosis
  • Parasomnias / physiopathology*
  • Polysomnography
  • Prepulse Inhibition / physiology
  • Reflex, Startle / physiology
  • Sleep Stages / physiology*
  • Wakefulness / physiology
  • Young Adult