Why Deep Sleep Is Important For Mental Health

There is new evidence that REM (rapid eye movement) sleep helps us process our inner fears, frustrations, and passions.

Previous research already provided evidence that REM sleep helps us process these emotions. But the new study published in Science and conducted by researchers from the University of Bern and University Hospital Bern in Switzerland tells us how it happens.

According to the researchers, our neurons in front of the brain may be busy reinforcing positive emotions while cushioning our most negative and traumatic ones as a protective mechanism. Our neurons also act as the messenger cells of our brains.

The study findings reinforce how important sleep is for our mental health. They may also lead to new therapies for a number of mental health conditions.

The findings came after the researchers studied brain activity in mice during wakefulness, REM, and non-REM sleep. Study author Mattia Aime, a post-doctoral researcher in the Department of Biomedical Research at the University of Bern, said they wanted to find out why the prefrontal cortex, or the front of the brain, actively integrates many emotions when we’re awake but is mostly inactive while we’re asleep.

The neurons have three key parts – the dendrites, axons, and the cell body. Dendrites receive information and pass it to the cell body. The cell body transfers that information to the axons that then help send it to other neurons.

The researchers discovered that during REM, the cells stopped transferring information, and the emotional content was stored at the dendritic level.

“This means that the dendrites, active during REM sleep, provided a substrate for consolidation,” Aime said, noting that they block any outgoing information related to danger. “This is essential to optimize the consolidation of emotional memories. Dendrites store information, cell bodies [become] inactive to avoid over-storage.”

In the future, the findings may help with the treatment of mental health conditions related to sleep, such as posttraumatic stress disorder, or PTSD.

“These findings pave the way to a better understanding of the processing of emotions during sleep in the mammalian brain and open new perspectives for new therapeutic targets,” Aime added.