Symptoms
Sleep-related behavior disorders are classified according to the stage of sleep in which the abnormal behavior primarily occurs.
Hallucinations
The most common hallucination, which also occurs in healthy individuals, is the strong feeling of a stranger in the bedroom.
Sleep paralysis
Sensation of completely paralyzed muscles during normal wakefulness, may cause fear of death the first time. Also occurs in healthy individuals (often familial).
Speaking in sleep
(Somniloquy)
More or less intelligible speech during sleep; rarely patients can answer questions during this process.
Moaning in sleep (Catathrenia)
When exhaling, the affected person makes repeated, prolonged moaning sounds, sometimes very loud, which they themselves do not perceive, but which can wake up their bed partner.
Sleepwalking and confusional awakening
Sleepwalking typically occurs during deep sleep. It is assumed that certain brain centers for motor function are already awake, while the brain areas controlling memory and rational behavior are still asleep. This often leads to accidents, e.g. falling down stairs, falling out of a window, eating inedible or toxic substances, and even alleged suicide. Sleepwalkers develop inexplicable strength, move furniture around and feel much less pain than when awake.
Confusional awakening, in which patients have not yet left the bed, only sit up and look around with a blank stare or mumble something. This is a preliminary stage. Upon awakening, the affected persons appear confused for several minutes and typically do not remember their actions or dreams in concrete terms.
Bedwetting
Often bedwetting happens during deep sleep, when the urge to urinate is not enough to wake the sleeper.
Sleep-related eating
Sleepwalkers tend to go to the refrigerator infrequently (Sleep-related Eating Disorder). This must be distinguished from the more frequent nocturnal eating while awake (Nocturnal Eating Syndrome). Both forms can lead to weight gain.
Sex-Somnia
Predominantly male sufferers may sexually assault a partner in the bed during a sleepwalk episode.
Sleep-Driving
During a sleepwalking episode, sufferers may get into a car and drive away, but accidents are more common.
Sleep crime
During a sleepwalking episode, sufferers may attack their partner in the bed, sometimes seriously injuring or even killing them. A famous case was that of Ken Parks, who drove a long distance in a car during a sleepwalking episode and shot his mother-in-law in a distant town. As sleepwalking was proven to be the most likely cause, he was initially acquitted. However, he was later criticized for not having effectively prevented access to the car keys and a gun while aware of his sleepwalking.
Nightmares
Dreams during REM sleep, which are fearful and long-lasting, are called nightmares. Such nightmares occur particularly frequently after psychological trauma in the context of a post-traumatic stress reaction. Upon awakening, the affected persons are very quickly oriented and remember the dreams in detail. The fear of further nightmares may mean that affected persons and especially children often suffer from difficulties in falling asleep.
Dream-Sleep-Behavior Disorder
During REM sleep, dreamers perform wild movements that lead to self-injury or injury to their partner in the bed because they have to defend themselves in the dream against a supposed burglar or against wild animals. In the sleep laboratory, it can be shown that the muscles in these patients are not completely paralyzed during REM sleep as in healthy dreamers.
Causes
In the case of sleep-related behavior disorders, a dissociation between the different sleep-wake states is suspected. In contrast to the normal sleeper, in which the whole brain is in the same state, it is assumed that parts of the brain are in the awake state, while at the same time other areas are still in deep sleep or in dream sleep. Besides a strong genetic component, various triggering factors are considered that can lead to deeper sleep, such as a previous lack of sleep, alcohol consumption in the evening or consumption of sleeping pills. Various waking factors are also considered as triggers, such as obstructive sleep apnea syndrome, periodic leg movements during sleep, psychosocial stress, but also external disturbances by the partner in the bed, pets or street noise.
It has been known for several years that dream-sleep behavior disorder is in many cases a harbinger of Parkinson’s disease or dementia. In other cases, it masks chronic alcohol consumption, narcolepsy, or severe restless legs syndrome.
What we can offer
Treatment/progression
Treatment of sleep-related behavior disorders focuses on counseling regarding protective measures and behavioral therapy. Sleepwalkers should close doors and windows as well as possible and access to poisons, weapons, other sharp objects or car keys should be made impossible. All factors that promote deeper sleep as well as waking factors should be avoided. This can be achieved by having a regular and sufficiently long sleep at night, but also by clarification and possible treatment of disturbed sleep (sleep apnea syndrome, periodic leg movements during sleep, neck myoclonus, insomnia due to psychosocial stress, etc.). Many neurological diseases such as epilepsy, Parkinson’s disease or dementia should be considered as differential diagnosis or as cause of the nocturnal behavioral disorders.
One final approach is to consider the use of certain drugs: a rather weak effect is attributed to melatonin and a stronger effect is observed with clonazepam. However, worsening of sleep-related behavioral disorder has been reported with other benzodiazepines.
