Rochester Medicine

A Clean Sleep

Jun. 23, 2014

sleeping people

NPR, the BBC, and NBC are among the many national and international news outlets reporting on a recent study led by University of Rochester researcher Maiken Nedergaard, M.D., D.M.Sc.

Click here to listen to the NPR story, Brains Sweep Themselves Clear of Toxins During Sleep, by Jon Hamilton

Click here to read Sleep 'cleans' the brain of toxins by BBC health and science reporter James Gallagher

Click here to see the NBC report, A good night's sleep scrubs your brain clean, researchers find

Nedergaard's team investigation showed a recently discovered system that flushes waste from the brain is primarily active during sleep. This revelation could transform scientists’ understanding of the biological purpose of sleep, and point to new ways to treat neurological disorders.

“This study shows that the brain has different functional states when asleep and when awake,” says Nedergaard, co-director of the URMC Center for Translational Neuromedicine. “In fact, the restorative nature of sleep appears to be the result of the active clearance of the by-products of neural activity that accumulate during wakefulness.”

The study, which was published in the journal Science, revealed that the brain’s unique method of waste removal – dubbed the glymphatic system – is highly active during sleep, clearing away toxins contributing to Alzheimer’s disease and other neurological disorders. Furthermore, the researchers found the brain’s cells reduce in size during sleep, allowing waste to be removed more effectively.