The term parasomnia covers a variety of unusual physiological and behavioural phenomena which can occur during sleep, ranging from unusual movements and behaviours to dreams/nightmares, night terrors, sleep-walking and sleep-talking. Most parasomnias are intermittent and benign; however, some can pose a significant problem to an individual’s health and safety.
Parasomnias can be classified as primary (occurring in their own right), or as secondary (meaning that they occur because of another medical condition). Most parasomnias are disorders of arousal, partial arousal or sleep-stage transition and have a strong genetic basis. There are a number of ways to diagnose parasomnias and a range of treatments available.