Bad dreams can help people react better to frightening situations when they're awake, a finding that could lead to dream-based therapies for anxiety, Swiss researchers say.
They analyzed the dreams of 18 people and pinpointed which brain areas were activated when participants experienced fear in their dreams.
"For the first time, we've identified the neural correlates of fear when we dream and have observed that similar regions are activated when experiencing fear in both sleep and wakeful states," said Lampros Perogamvros, a researcher in the Sleep and Cognition Laboratory at the University of Geneva in Switzerland.
His team also found that after the volunteers woke up from a bad dream, brain areas that control emotions responded to frightening situations much more effectively, according to the study published recently in the journal Human Brain Mapping.
"We identified two brain regions implicated in the induction of fear experienced during the dream: the insula and the cingulate cortex," Perogamvros said in a university news release.
When a person is awake, the insula automatically activates when someone feels afraid, while the cingulate cortex assists in motor and behavioral reactions to threats.
In further tests with 89 volunteers, researchers found a strong link between emotions while dreaming and while awake. They said this reinforces a theory that people simulate frightening situations while dreaming in order to better react to them when they're awake.
"Dreams may be considered as real training for our future reactions and may potentially prepare us to face real-life dangers," Perogamvros said.
Based on their findings, the researchers plan to assess a new form of dream therapy to treat anxiety disorders.
They noted that bad dreams - in which the level of fear is moderate - differ from nightmares, which cause high levels of fear, disrupt sleep and have a negative effect when a person awakens.
"We believe that if a certain threshold of fear is exceeded in a dream, it loses its beneficial role as an emotional regulator," Perogamvros said.