http://articles.mercola.com/sites/articles/archive/2007/03/01/why-skipping-sleep-harms-your-brain.aspxLack of sleep may cause the brain to stop producing new cells. A study on rats showed that lack of sleep caused a stress hormone to affect the hippocampus, a brain region involved in forming memories. Rats who were deprived of sleep for 72 hours had higherenCommunityServer 2008.5 SP1 (Build: 31106.3070)