Introduction to parasomnias

Parasomnias are undesirable behaviours or experiences that occur while falling asleep, sleeping or waking.

Parasomnias are classified into 3 broad groups according to the stage of sleep in which they occur:

• non–rapid eye movement (non-REM) parasomnias (eg sleep terrors, confusional arousals, sleepwalking)
• rapid eye movement (REM) parasomnias (eg nightmares, REM sleep behaviour disorder)
• parasomnias occurring in either or both non-REM or REM sleep (eg sleep-related eating disorder, sleep-related enuresis).