The brain has an internal clock that controls the rhythm of the day. Small areas in the brain stem and hypothalamus are responsible for telling the rest of the brain when it's time to sleep. These areas may be more active during sleep in people with insomnia.
U.S. News's featured content providers were not involved in the selection of advertisers appearing on this website, and the placement of such advertisement in no way implies that these content providers endorse the products and services advertised. Disclaimer and a note about your health.
