Parasomnia refers to a sleep disorder characterized by abnormal behavior during sleep or during a semi-sleep state.  The quality or quantity of one’s sleep is not necessarily affected by these events. The first part of the word (para) denotes a partial sleep, because most episodes occur during partial arousal or partial sleep states. Examples of parasomnia are sleepwalking (somnambulism), sleep talking (somniloquy), sleep eating, sleep driving, nightmares, night or sleep terrors, and bedwetting.