OXFORD University researchers say they have found the “switch” in the brain that sends people to sleep.
The findings, reported in the journal Neuron, could pave the way for new drugs to treat insomnia and other sleep disorders.
While the discovery was made on fruit flies, the team says the mechanism — which controls a handful of nerve cells in the brain — is also likely to operate in human brains, which have a similar group of nerve cells.
“When you’re tired, these neurons shout loud and send you to sleep,” said co-author Gero Miesenböck of Oxford’s Centre for Neural Circuits and Behaviour.
Scientists have long known about the neurons, which are switched on by general anaesthetics, but have not understood how they are activated under normal circumstances.
The body clock, which attunes creatures to the cycle of day and night, is not enough in itself to put them to sleep, Professor Miesenböck said. A “homeostat” in the brain also keeps track of waking hours and triggers sleep when it is time to “reset”.
He said the homeostat acted like household thermostats which turn on heaters when the temperature drops.
“The sleep homeostat measures how long a fly has been awake and switches on a small group of specialised cells in the brain if necessary,” he said.
“It’s the electrical output of these nerve cells that puts the fly to sleep.”
The team pinpointed the homeostat’s location by studying “mutant” fruit flies. A fault in a molecular component of the flies’ brains left the sleep-inducing neurons permanently switched off, causing insomnia.
The researchers said the flies could not catch up on their sleep after being kept awake all night. They exhibited the same sorts of learning and memory problems seen in sleep-deprived humans, and were “prone to nodding off”.
“The big question now is to figure out what internal signal the sleep switch responds to,” said co-author Diogo Pimentel.
The answer could provide insights into the “big unanswered question” of why animals needed sleep in the first place.
Source: The Australian
Comment: We hope you are not reading this to solve your sleep problem, because it doesn’t. It appreciates more about the mechanisms of sleep, but does not address the “why” factor, which even the researchers acknowledge.
So, finding other avenues of drug management as a consequence of this may help you get sleep, but not help restore a normal sleep pattern… and even prevent it happening.