The blog of Xeno, a slightly mad scientist
Image: Brainwashing. When mice sleep, fluid-filled channels (pale blue) between neurons expand and flush out waste.
It’s no secret that too little shut-eye can drain your brain, but scientists haven’t fully understood why.
Now, a new study suggests that a good night’s sleep leaves you feeling sharp and refreshed because a newly discovered system that scrubs away neural waste is mostly active when you’re at rest.
It’s a revelation that could not only transform scientists’ fundamental understanding of sleep, but also point to new ways to treat disorders such as Alzheimer’s disease, which are linked to the accumulation of toxins in the brain.
“We have a cleaning system that almost stops when we are awake and starts when we sleep. It’s almost like opening and closing a faucet – it’s that dramatic,” says Dr. Maiken Nedergaard, co-director of the Center for Translational Neuromedicine at the University of Rochester Medical Center.
Nedergaard is the lead author of the study published Thursday in the journal Science. She and her colleagues first reported last year their discovery of the brain’s unique waste removal system, dubbed the glymphatic system. It works like a neural trash truck, clearing away toxic by-products that build up when you’re awake.
The scientists had used two-photon microscopy – a new imaging technology that allows scientists to see deep inside living tissue – to peer into the brains of mice, which are remarkably similar to human brains. …