New Study Says Bedtime Routines are Part of Our Survival Instinct

Updated October 17, 2023

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Since the 1800s, sleep experts have recommended healthy sleep hygiene habits. Trusted Source National Library of Medicine, Biotech Information The National Center for Biotechnology Information advances science and health by providing access to biomedical and genomic information. View Source These sleep tips often include advice to practice a calming bedtime routine each night. Trusted Source Medline Plus MedlinePlus is an online health information resource for patients and their families and friends. View Source

A recent study by researchers at the Imperial College London in England published in Nature Neuroscience suggests that practicing a bedtime routine might be even more critical than experts once thought. Preparing for sleep may be a tendency embedded in the brains of all mammals, including humans, and is part of the survival instinct.

Kyoko Tossell, Ph.D., one of the study’s lead researchers, told Sleep Foundation that the inclination to prepare for sleep is likely a “hard-wired process in the brain.” But, we “often neglect [maintaining a bedtime routine] as we grow older.”

To understand how mammals prepare for sleep, the research team looked at the brains and actions of mice. First, they made the mice feel sleepier by showing them unusual items, like Legos and other toys, to keep them awake for five hours beyond their regular bedtimes.

As the mice became sleepier, the researchers watched how they acted and what happened in their brains. The study team used methods called optogenetics and chemogenetics to watch the mice’s brain activity.

Mice took more actions to prepare for sleep as they became more tired. Tossell shared that these preparation activities included seeking a safe location and building a comfortable and hygienic nest near the water and food supply.

As the mice prepared for sleep, nerve cells in the front of their brains (the prefrontal cortex) sent messages to the base of the brain (the hypothalamus), which controls many actions related to survival, like sleeping and eating.

“When tiredness starts to wash over the mouse, the top part of the brain decides to implement behavior to make sure the mouse is in a safe and comfortable place before going to sleep,” Tossell says.

Tossell explained in a university news release that “It is very likely that the same wiring exists in the human brain as the mouse brain [and] we are probably governed by unconscious urges to prepare for bed as mice are.”

William Wisden, Ph.D., Chair of Molecular Neuroscience at Imperial College London and another researcher on the study, told the university’s news team that preparing for sleep is “a survival feature.” Wisden also suggests that many humans likely ignore this natural tendency.

Both Tossell and Wisden encourage people to take good sleep hygiene seriously. Examples Wisden gave include going to bed at a set time, avoiding digital devices before bedtime, and sleeping on a good mattress with nice sheets and blankets.

More research is needed to determine exactly how this tendency to prepare for sleep affects humans, but following regular bedtime routines and optimizing our bedroom environments so we feel safe and comfortable can help us get quality rest.

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Written By

Jay Summer, Staff Writer

Jay Summer is a health content writer and editor. She holds a B.S. in psychology and master's degrees in writing and public policy.

Learn more about our Editorial Team

References
4 Sources

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https://pubmed.ncbi.nlm.nih.gov/22752854/
Changing your sleep habits. (2022, May 12). MedlinePlus Medical Encyclopedia.
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Tossell, K., Yu, X., Giannos, P., Soto, B. A., Nollet, M., Yustos, R., Miracca, G., Vicente, M. C., Miao, A., Hsieh, B., Ma, Y., Vyssotski, A. L., Constandinou, T. G., Franks, N. P., & Wisden, W. (2023). Somatostatin neurons in prefrontal cortex initiate sleep-preparatory behavior and sleep via the preoptic and lateral hypothalamus. Nature Neuroscience, 26(10), 1805–1819.
https://www.nature.com/articles/s41593-023-01430-4
Dunning, H. (2023, September 21). Getting ready for bed controlled by specific brain wiring in mice. Imperial News.
https://www.imperial.ac.uk/news/247873/getting-ready-controlled-specific-brain-wiring/