A European Science Foundation (ESF) workshop has found similarities in brain activity during lucid dreaming and psychosis, which could mean that dream therapy may be useful in psychiatric treatment.
Lucid dreaming, when a person is aware that he/she is dreaming, is a hybrid state between sleeping and being awake. It creates distinct patterns of electrical activity in the brain that have similarities to the patterns made by psychotic conditions, such as schizophrenia.
Ursula Voss, from the University of Frankfurt in Germany, points out that confirming links between lucid dreaming and psychotic conditions offers potential for new therapeutic routes based on how healthy dreaming differs from the unstable states associated with neurological and psychiatric disorders.
According to Voss, dissociation involves losing conscious control over mental processes, such as logical thinking or emotional reaction.
In some psychiatric conditions this state is also known to occur while people are awake, Voss adds.
"In the field of psychiatry, the interest in patients' dreams has progressively fallen out of both clinical practice and research.
But this new work seems to show that we may be able to make comparisons between lucid dreaming and some psychiatric conditions that involve an abnormal dissociation of consciousness while awake, such as psychosis, depersonalisation and pseudoseizures."said the workshop's convenor Silvio Scarone, from the Universita degli Studi di Milano in Milan, Italy.
The new findings have revived clinicians' interest in the previously discredited idea of treating some conditions with dream therapy-for example, people suffering from nightmares can sometimes be treated by training them to dream lucidly so that they can consciously wake up.
"On the one hand, basic dream researchers could now apply their knowledge to psychiatric patients with the aim of building a useful tool for psychiatry, reviving interest in patients' dreams. On the other hand, neuroscience investigators could explore how to extend their work to psychiatric conditions, using approaches from sleep research to interpret data from acute psychotic and dissociated states of the brain-mind," says Scarone.
The research team also studied the idea that paranoid delusions and other hallucinatory phenomena occur when the dissociative dreaming state involving replay of threatening situations is carried through into wakefulness.
"Exposure to real threatening events supposedly activates the dream system, so that it produces simulations that are realistic rehearsals of threatening events in terms of perception and behaviour.
This theory works on the basis that the environment in which the human brain evolved included frequent dangerous events that posed threats to human reproduction. These would have been a serious selection pressure on ancestral human populations and would have fully activated the threat simulation mechanisms," said Scarone.
However, dreaming is unlikely to have evolved purely to recreate threats, as Allan Hobson, a psychiatrist and dream researcher who recently retired from Harvard University in the US, insists that it may also have a role in the learning process.
Contents are added while you are awake and integrated with the automatic program of dream consciousness during sleep. This works with observations that daytime learning is consolidated by night-time sleeping, leading to the phenomenon where people remember facts better the day after they have learnt them than at the time.