Parasomnias are phenomena, either behavioral or physiological, that intrude into the sleep process and by themselves, are not primarily disorders of sleep and wake states. These disorders are manifestations of central nervous system activation usually transmitted through skeletal muscle or autonomic, or involuntary, nervous system channels. They include nightmares/night terrors, sleepwalking, REM behavior disorder (RBD), clenching or grinding of the teeth (bruxism), bedwetting and others. Although these disorders can be normal in children or adults (if they occur only occasionally), parasomnias can be disruptive to the sleeper, bed partner or other family members when the episodes become frequent or particularly intense.
A careful sleep history and sometimes an overnight sleep study are needed to diagnose and treat parasonmias.
Nightmares are frightening dreams that usually awaken the sleeper during REM sleep. Night terrors are characterized by sudden arousal from slow wave sleep with a piercing scream or cry, followed by manifestations of intense fear and a temporary inability to regain full consciousness. The person is usually inconsolable, and will not remember the event in the morning.
Sleepwalking consists of a series of complex behaviors that are initiated during slow wave sleep and result in walking during sleep. There may be difficulty in arousing the patient during a sleepwalking episode and amnesia afterward is common.
REM Behavior Disorder (RBD)
During REM sleep a person is paralyzed except for the eyes and breathing muscles. This is called atonia. In Rem Behavior Disorder (RBD) muscle atonia does not occur and the sleeper is free to exhibit elaborate motor activity associated with dreaming. These behaviors may be violent or injurious to the sleeper and may disrupt sleep continuity.
Bruxism is a movement disorder characterized by grinding or clenching of the teeth during sleep. Bruxism may cause abnormal wear of the teeth or jaw muscle discomfort. Bruxism may increase in severity during times of stress or when another sleep disorder such as Obstructive Sleep Apnea (OSA) is present.
Bedwetting or sleep enuresis, is the recurrent and involuntary voiding of urine during sleep. Bedwetting can be associated with other medical conditions such as diabetes, urinary tract infection or epilepsy. These conditions need to be properly treated before other treatments for bedwetting can be explored.