Other parasomnias

**Definition:** Other parasomnias include Hypnogogic exploding head syndrome, Sleep-related hallucinations, and abnormal sleep related complex movements, behaviours, emotions, perceptions, dreams, or autonomic nervous system activity related to a medical condition or due to a medication or substance. The experiences are sufficiently severe to result in significant distress or significant impairment in personal, family, social, educational, occupational or other important areas of functioning or significant risk of injury to the individual or to others.