REM sleep crucial for emotional health: study


July 5, 2022 – REM sleep is the darling of the sleep world. Short for “rapid eye movement,” REM fascinates us because it’s when we do most of our dreams — when, supposedly, all our inner fears, frustrations, and passions are at play.

We already have compelling evidence that REM sleep helps us process those emotions, but a new study reveals how.

It turns out that neurons (messenger cells) at the front of the brain may be busy amplifying positive emotions, while also dampening our most negative and traumatic emotions, say researchers from the University of Bern and University Hospital Bern in Switzerland. . It is a protective mechanism, they believe.

The findings not only reinforce the importance of sleep for mental health, but may also lead to new therapies for some mental illnesses.

How sleep helps us process emotions

The researchers came to their conclusions after studying brain activity in mice during wakefulness, REM and non-REM sleep.

They wanted to know why the front of the brain — the prefrontal cortex — actively integrates many emotions when you’re awake, but appears inactive during REM sleep, said lead study author Mattia Aime, a postdoctoral researcher in the Department of Biomedical Research at the University of Bern. . It is a mind-boggling phenomenon, the authors note in their study in the journal Science

Neurons have three main parts, Aime explains: dendrites, axons, and the cell body (soma). Dendrites receive information and send it to the cell body. Then the information is transferred to axons that help to send it to other neurons. So dendrites pull information in and axons send it out.

But the researchers found that during REM, emotional content was stored at the dendritic level and the “output” part of the cell stopped communicating.

“This means that the dendrites, active during REM sleep, formed a substrate for consolidation,” says Aime, blocking all outgoing messages related to danger. Think of it as a “whisper on the track” game that ends when someone receives a scary or negative whisper and doesn’t pass it on to the next person.