Brain neurons identified in pre-sleep routine
Newswise – When we’re stressed or excited, it can be hard for us to fall asleep – and finding ways to unwind before sleep is a habit for many.
For people with chronic difficulty initiating and maintaining sleep, adopting a regular pre-sleep behavioral routine has been shown to be more effective in facilitating sleep than medication, but the biological link between the pre-sleep phase -sleep and sleep initiation was until recently a mystery.
Now, a new study from the University of Michigan provides new insights into the mechanisms that control pre-sleep behaviors and subsequent sleep initiation.
The findings, which are published in Current Biology, could have important implications for insomniacs, who chronically struggle to fall asleep and maintain sleep.
Humans, as well as many other animals, including mice, engage in routine behaviors before sleep initiation, including maintaining personal hygiene and preparing a space in which to sleep. It has long been suggested that these pre-sleep behaviors promote tranquilization and de-energize the brain, but causal evidence has been lacking.
In the recently published study, UM researchers characterized mice’s pre-sleep routine and demonstrated that if mice are not able to engage in pre-sleep nesting behavior, they need more time to fall asleep and the quality of their sleep is reduced.
The researchers used newly developed state-of-the-art methods to label neurons activated during the pre-sleep phase and then modulate their activity. They succeeded in identifying neurons or brain cells in the lateral hypothalamus – which is a brain structure located in the forebrain and responsible for many behaviors, including hunger, fear and thirst – which not only control the behavior of nesting before sleep, but also the intensity of sleep.
The findings could eventually lead to the development of alternative drugs to treat sleep disorders, other than currently available prescription drugs that pose many health risks.
“A better understanding of the neural mechanism facilitating the natural transition from wakefulness to sleep could have important implications for many humans for whom this transition is not trivial, for example for people suffering from insomnia,” said Ada. Eban-Rothschild, assistant professor. of psychology and neuroscience and lead author of the study.
The study’s co-authors are Maria Ines Sotelo, Jean Tyan, Chelsea Markunas, Bibi Sulaman, Lorraine Horwitz, Hankyu Lee, Joshua Morrow, Gideon Rothschild and Bo Duan, all from the University of Michigan.
Study: Lateral hypothalamic neural ensembles regulate pre-sleep nest building behavior