Click here to view next page of this article

 

Sleep terrors

Sleep terrors are characterized by a sudden arousal from slow-wave sleep with a piercing scream or cry, accompanied by autonomic and behavioral manifestations of intense sleep terrors.

The condition may be closely related to sleepwalking, as the polysomnographic recordings of the two conditions are similar. Like sleepwalking, sleep terror is an arousal from slow-wave sleep in the first half of the night, accompanied by a piercing scream and behavioral manifestations of nightmares and parvor nocturnus. 

Before a sleep terror episode, the EEG delta waves may be higher in amplitude than usual, and respiration and heart rates may slow. During the attack, however, an alpha pattern appears, and there is tachycardia. The person typically sits up in bed, appears agitated and frightened, and may perspire and exhibit automatism, mydriasis, and tachypnea. Full consciousness is gained after five or ten minutes and the episode is rarely remembered.

More common in boys, sleep terror is experienced by at least 1 to 4 percent of all children (parvor nocturnus). Its onset is frequently between the ages of 4 years and 12 years, disappearing in early adolescence. The disorder occasionally does not begin until the second or third decade of adulthood (incubus), but rarely commences.

Psychophysiological functioning in children with sleep terrors is within normal limits and such children are not more predisposed to mental illness in later life. Adults with the disorder, however, are prone to disturbances.

Sleep terrors are often misrepresented as sleep anxiety attacks (nightmares), but are easily differentiated by the timing of episodes in the sleep cycle (earlier in the night), a marked degree of sympathetic arousal, and the lack of vivid dream recall. They may also resemble the hypnagogic hallucinations of narcoleptics and depressed patients.

Treatment often is not necessary. Reassurance of the events' generally benign nature, lack of psychological significance, and their usual tendency to diminish over time, often is sufficient. Benzodiazepines (clonazepam) or tricyclic antidepressants (imipramine) may be effective, and should be administered if the behaviors are dangerous to person or property or extremely disruptive to family members. Paroxetine and trazodone have been reported effective in single cases.

Nonpharmacologic treatment such as psychotherapy, progressive relaxation, hypnosis, or anticipatory awakening is recommended for long-term management. Avoidance of potential triggering factors such as drugs, alcohol, and sleep deprivation.