Deep sleep helps the brain cope with stress: Scientists identify a possible mechanism

The quality of deep sleep may affect the body’s ability to cope with stress, according to U.S. scientists who studied brain activity in mice during sleep.

The findings were published in the scientific journal Journal of Neuroscience.

Researchers from Morehouse School of Medicine focused on the prelimbic cortex, a brain region that helps link emotional responses to the context in which events occur. In mice that were better able to cope with stressful social situations, neurons in this region showed greater suppression of activity during deep sleep.

The slow-wave sleep period, considered the deepest stage of sleep, appeared to be particularly important. The pattern of neuronal suppression during this stage helped predict how resilient an animal would be to stress.

After exposure to a stressful experience, the organization of neural activity in the prelimbic cortex also changed, with the rate of neuronal activity being redistributed. According to the researchers, deep sleep may provide a kind of “tuning” of brain mechanisms that help regulate emotional responses to stress.

“It appears that sleep quality determines how the prelimbic cortex suppresses emotional responses,” said study leader Christopher Ellen.

The researchers suggest that animals that are more vulnerable to stress may experience less deep sleep, while deep sleep may help preserve the brain’s ability to respond effectively to stressful situations.

As a next step, the researchers plan to investigate whether the activity of the prelimbic cortex changes in stress-resilient mice when they are deprived of sleep. In the longer term, the findings could help identify neurobiological markers of increased resilience — or vulnerability — to stress in humans.