Although not everyone sleepwalks, enough of the general population (around 30 percent) has sleepwalked at least once in their lives to include it on this list. Also called somnambulism, sleepwalking is technically a sleep disorder in which the brain is in a semiconscious state, performing complex tasks such as getting out of bed, going to the kitchen, even driving.
Obviously, this can be very dangerous. But sleepwalking is relatively common, especially among children. Parents, roommates, and friends often report that the somnambulist in question will act dazed and confused while performing bizarre behaviors such as preparing a meal, only to return to bed.
Scientists still are not sure why people sleepwalk, although research has shown that it may be genetic. Sleepwalking usually occurs during slow-wave sleep, in which the brain is busy processing the day’s memories.
This may explain why a sleepwalker’s short-term memory is not very active while in this trancelike state. In fact, the person in question will have no memory whatsoever of the previous night’s events when they wake up in the morning.