A good night’s sleep not only recharges the body, but also cleans and clears the mind of disease-causing agents, researchers have found.
The study embarked at the University of Rochester Medical Centre, researchers found that a good night’s sleep allowed the brain cells to shrink, leading to opening up of gaps between neurons that flushed fluid to wash away the waste toxins accumulated during a hard day’s work.
“The brain only has limited energy at its disposal and it appears that it must choice between two different functional states – awake and aware or asleep and cleaning up,” study’s lead researcher, Maiken Nedergaard, co-director of the University of Rochester Medical Center (URMC) Center for Translational Neuromedicine said.
Explaining the concept of the study, Nedergaard added, “You can think of it like having a house party. You can either entertain the guests or clean up the house, but you can’t really do both at the same time.”
The findings of the study are based on experiments conducted on lab mice. As their brains are remarkably similar to humans, they were the best pick for the analysis.
Lab experiments on mice unfolded a brain’s unique method of waste removal, called the glymphatic system.
The glymphatic system which is 10 times more effective during sleep helped clear away toxins built up during the day’s task. This was possible when brain’s cells size reduced by almost 60 percent during sleep. This space between the cells allows cerebral spinal fluid (CSF) to flow through the brain tissue allowing waste to be scrubbed away more effectively.
A sleeping brain was more effective in removing amyloid-beta than an awake brain, the researchers highlighted. Accumulation of damaged amyloid-beta cells in the brain fuels neurological conditions like Alzheimer’s and Parkinson’s disease.
“This study shows that the brain has different functional states when asleep and when awake,” Nedergaard said. “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 significance is that, yet again, it shows sleep may contribute to the restoration of brain cell function and may have protective effects,” the team concluded.
The findings of the study are reported in the current issue of the journal Science.