Lack of Sleep: What It Does to Your Brain

Behind the controls of the Metro-North train that derailed in New York earlier this week was a tired driver, according to new reports that engineer William Rockefeller fell asleep at the wheel.
Could lack of sleep cause such a fatal mistake?
Biologically speaking, experts said, yes. Sleep deprivation affects the brain in multiple ways that can impair judgment, slow reaction times and increase the likelihood of drifting off during monotonous tasks.