Sleeping cleans your brain!
"Neuroscientists peeked into the brains of conscious and unconscious mice using a technique called two-photon microscopy. When the mice drifted off, their brain cells actually shrank, expanding the spaces between them by 60 percent. That’s when cerebral spinal fluid flowed in and cleaned the pipes."
According to Maiken Nedergaard, the study’s lead author, "One of the waste products removed from the brain during sleep is beta amyloid, the substance that forms sticky plaques associated with [Alzheimer's] disease. That’s probably not a coincidence.
“Isn’t it interesting that Alzheimer’s and all other diseases associated with dementia, they are linked to sleep disorders,” she says.More information is at http://blogs.discovermagazine.com/d-brief/2013/10/18/sleep-flushes-toxins-from-the-brain/