Scientists know we need sleep, but they don't know exactly why, and they've been pretty clueless about how the brain decides when to sleep.
Some of the mystery has been put to rest. A new study of mice finds that brain cells called astrocytes fuel the urge to sleep by releasing adenosine, a chemical known to have sleep-inducing effects that can be inhibited by caffeine.
The longer a person or animal is awake, the stronger the urge to sleep becomes. This is known as sleep pressure. Prior studies pointed to adenosine as a trigger for sleep pressure. The chemical accumulates in the brain during waking hours, eventually helping to stimulate the unique patterns of brain activity that occur during sleep.
The new study found "adenosine from astrocytes clearly regulates sleep pressure," said study team member Michael Halassa of Tufts University School of Medicine in Boston.
complete article at Livescience
No comments:
Post a Comment