Poor REM Sleep Linked to Depression & Anxiety

Sharon Moore February 23, 2016

Rapid eye movement (REM) is the most important stage of sleep in which dreams take place. It is characterised by random movement of the eyes, low muscle tone, and rapid low-voltage desynchronized brain waves.

In a new study by the U.S. National Institute of Neurological Disorders and Stroke, the bad and "restless" REM sleep experienced by insomnia patients may, in turn, undermine their ability to overcome emotional distress, raising their risk for chronic depression or anxiety.

Researchers found that when REM is underway, key arousal hormones such as serotonin, adrenaline and dopamine are inactive. This, he added, may indicate that it is during good REM sleep when the emotional impact of memories is properly processed and resolved. But when it is disturbed, emotional distress may accumulate. Over time this accumulation eventually leads to a "vicious cycle" of over-arousal, during which insomnia promotes distress, which promotes arousal, which promotes ongoing insomnia.

To demonstrate the importance of REM sleep in emotional regulation, the researchers conducted a two-part study. In the first one, nearly 1,200 respondents were asked to self-report the severity of their insomnia, as well as their emotional distress, and troubling night-time thoughts. The second part of the study involved 19 women and 13 men who were subjected to two nights of lab-monitored sleep, during which their electrical brain activity was recorded.

In both the studies, REM sleep was disturbed, the more trouble participants had in putting aside emotional distress. According to Rick Wassing, lead author of the study and a doctoral candidate in the Department of Sleep and Cognition at the Netherlands Institute for Neuroscience in Amsterdam, “while REM is underway, key arousal hormones such as serotonin, adrenaline and dopamine are inactive. This, he added, may indicate that it is during good REM sleep when the emotional impact of memories is properly processed and resolved.”

The findings were published in the Proceedings of the National Academy of Sciences journal.

Source of this article:

Slow dissolving of emotional distress contributes to hyperarousal