What they discovered was that during sleep, both the positive and negative emotions reappeared in the brain – however, the negative emotions associated with fear were effectively uncoupled and blocked during REM sleep. As the study puts it, “The brain favours the discrimination of safety versus danger in the dendrites, but blocks the over-reaction to emotion, in particular danger.”

“This bi-directional mechanism is essential to optimize the discrimination between dangerous and safe signals,” said researcher Mattia Aime.

In other words, during our dreams, our brains appear to process and understand negative emotion without ‘blowing it out of proportion’ or exaggerating it. So, when we wake from our dreams, we should have a proportional, measured understanding of our own fear and negativity.

Negative emotions? New research shows how sleep can help you feel more positive