According to research, getting enough Z’s could also help keep your brain healthy. A 2013 study found that during the overnight hours, the brain uses the time we sleep to flush out harmful toxins that build up over the course of the day. This study was conducted by researchers from the University of Rochester Medical Center (URMC), who relied on laboratory mice to conduct their research.

The authors of this report observed that mice had a system in place to expel waste from their brains. Specifically, surrounding the mice’s brains were a series of channels found adjacent to blood vessels. Through these channels flowed cerebrospinal fluid, which works to gobble up toxins and flush them out of the brain.

To put this theory to the test, the URMC team injected dye into the cerebrospinal fluid of a group of mice. This allowed the team to track the fluid as it moved through the brain. During the day, there was little in the way of movement, as the dye remained essentially stationary when the mice were awake. The story was quite different, however, when the mice slept. While the mice were catching some Z’s, the cerebrospinal fluid flowed freely and rapidly.

The researchers believe that better understanding this cleaning system could prove highly useful, potentially helping those struggling from long-term dementia. “These findings have significant implications for treating ‘dirty brain’ diseases like Alzheimer’s,” stated Dr. Maiken Nedergaard, the study’s senior author.