What happens when your body is awake, but your brain goes to sleep? It’s called microsleep, and it involves doing normal tasks or activities, such as driving, but not being able to recall doing them. You can’t remember if the light was red or green when you went through the intersection or if you checked your mirrors before you merged. Microsleep is a brief, involuntary episode of unconsciousness lasting anywhere from a moment to several seconds. It happens without warning and occurs most often when you are sleep deprived. It can be dangerous because you can make critical mistakes during these brief moments. In fact, the 2016 London tram derailment and 1986 Chernobyl nuclear accident have been linked to microsleep. Read more about the causes, dangers, and ways of preventing microsleep.