A small biological switch located in the brain has been controlling our forays into the world of dreams and has now been identified by a group of researchers at McGill University who may have also discovered how to activate it, which would have important repercussions on the brain. sleep medicine. Their findings have been published in the Journal of Neuroscience and will help improve understanding of the sleep mechanism and contribute to developing new treatments for sleep disorders and associated neuropsychiatric conditions.
REM sleep is essential for dreaming, consolidating memory, and regulating emotions. In addition, serious diseases such as Parkinson’s and dementia with Lewy bodies, which currently lack effective treatments, are related to disturbances in REM sleep. These scientists have identified the melatonin receptor MT1 as a crucial regulator of REM sleep.
In the brain, the melatonin receptor MT1 influences a type of neurons that synthesize the neurotransmitter and the hormone norepinephrine, located in a region known as the Locus Coeruleus or ‘blue spot’ in Latin. During REM sleep, these neurons reduce their activity, and the study reveals that activation of MT1 receptors in this region can trigger this calming effect, essentially flipping the switch to REM sleep.
“This discovery not only expands our knowledge of sleep mechanisms, but also has great clinical potential,” said Gabriella Gobbi, professor of psychiatry at McGill University, clinical scientist at the University Health Center Research Institute. McGill University, holder of the Canada Research Chair in Mental Health Therapeutics, and principal investigator of this study.
The Impact of REM Sleep on Cognitive Function
Human sleep follows a precise sequence of non-REM and REM phases, each with distinct physiological functions. REM sleep plays a key role in memory consolidation and emotional regulation, while non-REM sleep supports physical recovery and repair processes. Disruptions in this cycle can impair cognitive function and increase the risk of developing neuropsychiatric diseases.
Until now, scientists had not been able to identify the specific receptor that triggers REM sleep. This new study has revealed that the melatonin receptor MT1 is an important regulator of this phase of sleep. By using a novel drug targeting MT1 receptors, researchers were able to increase the duration of REM sleep in experimental animals, while reducing neuronal activity.
“Currently, there are no drugs that specifically target REM sleep. Most hypnotic medications on the market, although they prolong the total duration of sleep, tend to negatively affect REM sleep,” explained Dr. Stefano Comai, co-lead author of the study, professor at the University of Padua and adjunct professor at McGill University.
According to researchers, it is essential to continue delving into the neurobiology and pharmacology of REM sleep to develop specific treatments that improve the quality of life of patients affected by these debilitating diseases. As scientists continue to explore the complexities of sleep regulation, hope grows for effective interventions for neurological disorders.
