British researchers discovered a molecular switch in the brain of fruit flies tells them when it’s time for some shut-eye – and they believe that humans have a similar brain function.
Considering how essential good sleep is for our overall health, and that 50 to 70 million Americans suffer from a sleep or wakefulness disorder of some kind, the findings could be very important if they help us learn more about the brain functions that make sure we get a good night’s rest. Low-quality or inadequate sleep has been tied to health-related consequences like weight gain and depression.
In explaining the research, it helps to understand how the brain functions when it comes to sleep. Our brains have two mechanisms related to sleep: One monitors our external environment, and the other monitors the internal. For this study, researchers looked at the internal environment – specifically, the University of Oxford researchers looked at a homeostatic mechanism in the brain that tracks the number of waking hours in order to let the body know when it’s time to go to sleep and recharge.
One researcher compared the mechanism to a thermostat, which measures temperature in our homes and switches on if it’s too cold, or off once it’s warm enough. Similarly, in the flies they studied, the sleep homeostatic would switch on the cells that would get the fly to sleep if needed. The findings give us more information about the regulatory system in our bodies and brains that helps us match the intensity and quality of our sleep to meet our needs.
The study was conducted using mutated flies that had a non-functioning variant of the neurons related to sleep. The flies with the mutation became more and more sleep deprived; by contrast, the regular fruit flies were able to sleep when their brains got the internal signal.
In their research, the study authors discovered that the switch in the brain functions by controlling neurons that are active when we’re tired and in need of rest, and quiet when we’re caught up on sleep. The discovery was made in the brains of flies, but human brains have a similar group of neurons that is also active while we’re sleeping, and helps us to sleep.
The work is not without its caveats. Most importantly, the study was done on fruit flies and not humans; though the researchers have good reason to believe the same principles apply to human brain function, it’s not known for sure.
Though the research is still in the early stages, the researchers are hopeful that their findings could lead to new developments in treatments for sleep disorders, like insomnia. They also plan to expand the research to look at the brain function that flips the “switch” to begin with, and what those cells are monitoring while we’re awake.