Why do we fall asleep when bored?

Why do we fall asleep when bored?
Credit: University of Tsukuba

Humans often defy sleepiness and stay awake when attention is necessary,yet experience an inescapable desire to sleep in boring situations. The brain mechanisms governing the regulation of sleep by cognitive and emotional factors are not well understood. A new paper published in the journal Nature Communications finds that a part of the brain that is associated with motivation and pleasure, the nucleus accumbens, can also induce sleep. The new findings may explain why we have a tendency to fall asleep in the absence of motivating stimuli, i.e., when bored.

Researchers at the University of Tsukuba's International Institute for Integrative Sleep Medicine (WPI-IIIS) and Fudan University's Department of Pharmacology in the School of Basic Medical Sciences used chemo-genetic and optical techniques to remotely control the activities of accumbens neurons and the behaviors they mediate. As a result, the Japanese-Chinese team discovered that nucleus accumbens neurons have a strong ability to induce that is indistinguishable from the major component of natural sleep, known as , as it is characterized by slow and high-voltage brain waves.

"The classic somnogen adenosine is a strong candidate for evoking the sleep effect in the nucleus accumbens," says Yo Oishi, the lead author on this project. Adenosine has long been known to represent a state of relative energy deficiency and to induce sleep via . A specific subtype of adenosine receptors, the A2A receptors, are densely expressed in the nucleus accumbens. Caffeine, the most widely consumed psychostimulant in the world, produces its arousal effect in the nucleus accumbens by blocking A2A receptors. Compounds that activate A2A receptors in the may open safe therapeutic avenues for treating insomnia, which is one of the most common sleep problems with an estimated prevalence of 10 to 15 percent in the general population and 30 to 60 percent in the older population.

More information: Yo Oishi et al, Slow-wave sleep is controlled by a subset of nucleus accumbens core neurons in mice, Nature Communications (2017). DOI: 10.1038/s41467-017-00781-4

Journal information: Nature Communications
Citation: Why do we fall asleep when bored? (2017, September 29) retrieved 19 June 2024 from https://medicalxpress.com/news/2017-09-fall-asleep.html
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.

Explore further

New role of adenosine in the regulation of REM sleep discovered


Feedback to editors