Night terrors (sleep terror or pavor nocturnus) are a sleep disorder characterized by sudden crying, screaming, sweating, apparent fear and hysteria while asleep. A person experiencing a night terror is not awake and may often go back to sleep without recollecting the events. However a sufferer may awaken and continue to display the symptoms of a night terror for a few minutes after waking. Night terrors often occur in the non-REM (Rapid Eye Movement) stage of sleep.
A night terror differs from a nightmare and can affect any age group (infants, toddlers, young children, teens and adults) although it is more common in children under 5 years of age.
Nightmares are scary and disturbing dreams or ‘bad dreams’ that may induce symptoms similar to night terrors. Many sufferers can recall the nightmare and are aware that they had a nightmare upon waking. A nightmare occurs during REM (Rapid Eye Movement) stage of sleep or ‘deep sleep’ and will usually end immediately upon waking.
Parasomnia : Night Terror (Sleep Terror/Pavor Nocturnus) Disorder
Night terrors or sleep terrors are disorders categorized as a parasomnia. Usually in sleep, the body’s ‘sleep chemicals’ cause muscle atonia meaning that the body cannot move or act out dreams. This is often lacking in a parasomnia disorder where unnatural or abnormal body movements, emotions and behavior may be displayed while asleep. Other parasomnia disorders include sleepwalking disorder and nightmare disorder.
Parasomnia should not be not be confused with other sleep disorders like dyssomnia where the amount, quality and timing of sleep are affected. Common examples of dyssomnia are insomnia (difficult falling asleep or maintaining sleep) or hypersomnia (excessive sleepiness).