How essential is sleep health for our mental health?

We often talk about how essential sleep is for our physical wellness, from repairing injuries to digestion. But sleep is also a vital part of maintaining our mental health too. From a more obvious angle, the better-quality sleep we get the more we can manage stress, but researchers from the University of Bern and University Hospital Bern have now also found that dream sleep triages emotions, allowing us to store positive emotions and dampen the impact of negative ones.

Written by Bryony Porteous-Sebouhian

How dream sleep allows us to process emotion

Researchers at the University of Bern observed how emotions are processed during the state of sleep known as rapid eye movement (REM). This state is where the majority of our dreams occur as well as the experiencing of intense emotion.

On the University of Bern’s website , they state that the prefrontal cortex integrates many of our emotions, both positive and negative while we are awake, yet it appears surprisingly dormant during REM sleep.

“Our goal was to understand the underlying mechanism and the functions of such a surprising phenomenon.” Said Professor Antoine Adamantidis, lead researcher of the study from the Department of Biomedical Research at Bern University.

How we as humans and mammals process our emotions is vital in how we distinguish between what is safe and what is dangerous. When we are exposed to excessive negative emotions and stimuli we develop responses such as severe anxiety, or disorders such as post-traumatic stress disorder (PTSD).

Researchers at the University of Bern state that roughly 15% of the European population is affected by ‘persistent’ anxiety and severe mental illness.

Using two sets of stimuli, one associated with safety and another associated with danger, researchers observed brain activity in mice to determine how emotional memories are processed and transformed during REM sleep.

Through observing this process, researchers in the study found that, when in REM sleep, the mammalian brain favours the processing and consolidating of positive emotions – or those associated with safety – while negative emotions are blocked and not processed as deeply.

What does this mean for anxiety disorders or PTSD?

The findings of the study allude to the fact that if this discrimination is not present in the brain – aka favouring the deep processing of positive emotions versus negative – this can lead to excessive fear reactions. Researchers said the findings are particularly relevant to post-traumatic stress disorders because exposure to trauma – particularly repeated trauma – can mean memories of trauma etc. are ‘over consolidated’ in the prefrontal cortex, and this can happen day after day during sleep.

A breakthrough for the future of sleep medicine

The findings could help researchers and practitioners to create new therapeutic targets that treat the maladaptive processing of traumatic memories, through sleep. Patients who experience this lack of a discrimination for positive over negative emotions during REM may experience chronic stress, anxiety, depression, panic and even anhedonia, an inability to feel pleasure, researchers said.

Addressing how we sleep and what we do and do not process when we sleep is an innovative way to treat an underlying factor of what are some of the most complex mental health conditions, and brain functioning issues, such as PTSD and complex PTSD.

The University of Bern has a long history with sleep research and sleep medicine, lead researcher, Prof. Adamantidis said:

“We hope that our findings will not only be of interest to patients, but also to the broad public.”

You can read the full study here .