Rick Wassing, MSc, PhD-C: Restless REM Sleep Contributes to Hyperarousal In Insomnia

“The total time that people spent in REM sleep periods was predictive of the decrease of the amygdala response."

Research has identified hyperarousal as a key factor in the cause of chronic insomnia but mechanisms underlying hyperarousal have remained elusive, preventing targeted treatment.

At the 24^th Congress of the European Sleep Research Society, NeurologyLive spoke with Rick Wassing, MSc, PhD Candidate, Netherlands Institute for Neuroscience, to discuss present findings that suggest hyperarousal can result from an inadequate resolution of emotional distress, which is more likely due to restless rapid-eye-movement (REM) sleep.

Restless REM sleep reflects a process that affects overnight resolution of distress, and the accumulation of distress may promote the development of chronic hyperarousal giving clinical relevance to the role of REM sleep in emotion regulation in insomnia, depression and posttraumatic stress disorder. Those with chronic insomnia and restless REM sleep may never fully accomplish functional reorganization of emotional salience circuits because of overnight distress dissipation.

It’s important, according to Wassing, to asses in greater detail the fragmentation of REM sleep and how it impacts the regulation of emotional distress. Wassing adds that the more time patients were able to spend in the transition to REM sleep, the better subsequent REM sleep was able to de-potentiates the amygdala response, however, the inverse was also true in that with more arousals during REM sleep, the less that REM sleep was able to de-potentiates the amygdala response.

The findings conclude that overnight resolution of distress from shame is compromised in those with insomnia, contributing to hyperarousal, which is partly due to a high density of arousals and eye movements in REM sleep, and concomitant thought-like nocturnal mentation.