Beijing: Do you experience an inescapable desire to sleep in boring situations? A part of your brain linked to motivation and pleasure may be to blame!
Researchers at the University of Tsukuba in Tokyo and Fudan University in China used chemo-genetic and optical techniques to remotely control the activities of neurons in nucleus accumbens - associated with motivation and pleasure - and the behaviours they mediate.
The team found that nucleus accumbens neurons have an extremely strong ability to induce sleep that is indistinguishable from the major component of natural sleep, known as slow-wave sleep, as it is characterised by slow and high-voltage brain waves.
"The classic somnogen adenosine is a strong candidate for evoking the sleep effect in the nucleus accumbens," said Yo Oishi, lead author of the research published in the journal Nature Communications.
Adenosine has long been known to represent a state of relative energy deficiency and to induce sleep via adenosine receptors.
A specific subtype of adenosine receptors, the A2A receptors, are densely expressed in the nucleus accumbens.
Caffeine, the most widely consumed stimulant in the world, produces its arousal effect also in the nucleus accumbens by blocking A2A receptors, researchers said.
Compounds that activate A2A receptors in the nucleus accumbens may open safe therapeutic avenues for treating insomnia, which is one of the most common sleep problems with an estimated prevalence of 10-15 per cent in the general population and 30-60 per cent in the older population, they said.