We’ve known for some time that sleep is important for the restoration and strengthening specific functions in the brain linked to memory, regulating emotions, decision-making, and even creativity. But scientists are now discovering the processes through which sleep also cleans the brain like a plumbing system, in the process changing its cellular structure.

This research has led to an increasingly sophisticated understanding of the brain’s internal workings—and is one more reminder of why it’s so essential that humans make sure they get the proper amount of sleep. Previously, scientists thought the brain only cleaned itself by trickling toxins through brain tissues, but researchers now believe wastes are forcefully pushed through the brain at a much faster and higher pace, according to Maiken Nedergaard, co-director of the Center for Translational Neuromedicin at the University of…