Britannica Sources used in this answer

What can trigger sleepwalking and other NREM parasomnias?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

Hear how scientists are studying the sleep-related brain activity of animals and migratory birds — sleep Find out how scientists are studying the sleep activity of migratory birds.

NREM parasomnias, which include sleepwalking and sleep terrors, are disruptive sleep-related disorders that typically occur during the deepest stage of NREM sleep (N3). These episodes are characterized by EEG patterns that reflect a mix of sleep and wakeful states, leaving the individual generally unresponsive to external stimuli and often without memory of the event.12

Several factors can trigger these parasomnias, including:

Sleep deprivation or fragmented sleep1
Stress1
Fever1
Alcohol consumption1
Medications1

Additionally, some individuals may have a genetic predisposition to these disorders. Research into sleepwalking, for instance, suggests it often runs in families, with studies identifying potential links to specific regions of chromosome 20. While the exact mechanisms are not fully understood, these triggers likely disrupt the stability of the sleep cycle, leading to the partial arousals that define NREM parasomnias.13