Identifying bizarre behaviors in sleep

While sleep should be quiet and restful, in many it is marred by bizarre behavior including screaming, sleepwalking, feeling paralyzed or even acting out dreams or nightmares. These phenomena have fascinated scientists and artists for centuries, including Hippocrates, Aristotle, Galen and Shakespeare. Prior to 1968, it was assumed sleepwalking or sleep behaviors occurred during intense dreaming. However, some of these sleep behaviors are now better known as arousal disorders (from sleep).

Arousal disorders occur when an individual wakes up from a deep stage of sleep, known as slow wave sleep, during which alertness and cognition are at their lowest. Arousal disorders occur in predisposed individuals in response to a stimulus which causes an arousal or awakening and reflects an impaired transition into wakefulness from sleep. These stimuli could originate from a number of sources, including a noise, the urge to urinate or pain. Some of the most common arousal disorders are confusional arousals, sleepwalking and night terrors. Confusional arousals, often start with the individual sitting up in bed and looking about in a confused manner. When the patient leaves the bed, sleepwalking has been initiated. Sleepwalking is frequently associated with confusion, and the individual walks around with eyes open. Frequently, the individual can be redirected to get back in bed, in other instances the individual may become frightened and combative. Night terrors are characterized by a blood curdling scream which awakens an individual and causes them to be terrified. During this time, the individual appears scared, may resist being comforted, and may be combative and violent. With all arousal parasomnias, quiet sleep ensues shortly after the awakening and there is little or no memory of the event the next day.

Arousal disorders are common in children and most outgrow them. At times, this disorder may persist into adulthood. Sleeping pills, alcohol, stress and sleep deprivation are known triggers and causes of arousal disorders. Arousal disorders whenever severe or violent may result in psychological and social distress altering quality of life and causing daytime fatigue and sleepiness. Conservative approaches to protect the individual from injury may be all that is needed whenever the disorder is mild. In adults, the disorder may take a more dramatic form with complex behavior. This may include cooking and eating without being aware of one’s activities only to wake up the next day and find evidence of these activities. Sleep related eating disorders can lead to significant weight gain and related health problems. Sexual type behaviors have also been reported in parasomnic disorders. Nocturnal frontal lobe epilepsy, which is characterized by behavioral and motor activity, may mimic an arousal parasomnia and needs to be considered in some individuals; this requires completion of diagnostic sleep studies.

Although sleepwalking and night terrors are not dream enactment behaviors, REM Sleep Behavior Disorder often seem to represent vivid dream enactment. Most people dream during Rapid Eye Movement sleep, and the body is normally paralyzed during this time to protect itself from acting out its dreams. However, REM sleep behavior disorder is a parasomnia whereby the normal sleep paralysis of REM does not occur, and the individual exhibits motor activity during sleep with dream mentation. Although most of those patients are not abnormally aggressive during wake, the peculiar feature of dreams associated with RBD are usually aggressive. However, milder forms of RBD may only manifest in unusual but non-aggressive behavior. Frequently, there are early milder symptoms that may precede RBD for many years. These may be persistent sleeptalking, yelling, limb twitching and gross limb and body jerking. RBD is more common in older males but may be precipitated by a number of medications, including the very commonly used antidepressants such as Zoloft, Prozac and Paxil. Awareness of this unwanted effect of these medications is especially important since RBD may be mistaken as a symptom of a psychiatric disorder such as depression and may be made worse by such treatment. Since subclinical RBD may be an early sign of the disorder, both patients and clinicians should be aware that it may carry a risk for worsening of the symptoms as well as development of Parkinsonism or other neurological disorders in the future. Therefore, it is important that patients with symptoms of RBD discuss this with their physicians and undergo a thorough evaluation.

The diagnosis of parasomnias is mostly clinical, however, sleep studies performed with video monitoring and EEG analysis helps differentiate benign incidents from the more serious parasomnias. It is not always necessary for an incident to be recorded during a sleep study, as the abnormal sleep physiologic signals can be seen and recorded on a sleep study irrespective of parasomnic behavior. This is especially true in adults where it is crucial to identify the true nature of the disorder to ensure proper treatment as well as counseling regarding possible future progression of the disorder.

Article provided by The Neurology and Sleep Clinic.