What’s more, research has proven that our brains can only clean up after themselves during sleep. When we use our brains intensively, metabolic waste builds up—just like it does in our muscles. In our brains, however, this waste causes those feelings of fogginess, pressure, and irritability that we all know too well. What most of us don’t know is that our brains, unlike our muscles, are completely unable to clear this metabolic waste while we’re awake.
