Walk around or sleepwalking? Unconsciousness or crime?

There is a general assumption that walking during sleep means having somnambulism. It is an erroneous assumption that often leads to diagnostic errors and huge delays towards consulting a physician.

Why? Because walking during sleep may have several causes, and henceforth several possible treatments.

It can be due to somnambulism. Somnambulism is a well-defined illness: it is the most frequent in boys, it is familiar; it begins around 5 – 6 years of age and tends to disappear during adolescence. The occurrences usually appear during the Delta stage of sleep, known as Slow Wave Sleep, about one hour after falling asleep and won’t happen again in the same night. The sleepwalker scarcely remembers – if at all – what happened, walks around the house in an orderly but unconscious manner, which can amount to accidents, like falling through stairs, or through a window, breaking objects, etc. Usually he isn’t aggressive, but can become aggressive if forced or vexed.

Somnambulism can be provoked by certain psychoactive pills, and become worsened by alcohol, drugs, excessive exercise, fever or sleep deprivation.

Knowledge concerning this is very ancient. In Homer’s Odyssey happens to appear the first described case, and alcohol worsened, wherein Elpenor, Trojan war-hero, drunk some wine after a battle and climbed to a roof, where he slept. In the following morning, when he was called for boarding, he woke up, walked around the roof, and fell to his death. The Elpenor Syndrome is based on these events, and on the risks of roaming episodes when you are asleep or when you suddenly wake up in a confusional arousal.

Recently the movie “Side Effects” dealt about this matter, describing a crime perpetrated in a pseudo sleep walking episode, provoked by an antidepressant, and which would have been “perfect” if a psychiatrist had not been investigated through the policeman’s reasoning.

The psychiatrist could have used a more clinical approach, which means that whenever facing a case of nocturnal violence, one must investigate thoroughly and with exemption, performing tests, polysomnography and whatever is required to reproduce the violent episode, in order to achieve clear conclusions: is it a crime, does it result from illness or foul-play.

Violence during Sleep?

Yes, of course. Violence can exist during sleep and is, in that case, particularly dangerous. Why? Because who performs it is unconscious and the intensity of the acts can be enormous.

What are the causes?

Somnambulism, night terrors and the confusional arousals can be the cause of sleep related violence or accidents.

Another case is nocturnal epilepsy. Some epilepsies appear only or mostly during sleep, and manifest themselves through episodes with simple behaviours (limb movement, screams, etc.) or complex behaviours (walking, sitting on the bed, falling from the bed, aggression, striking, etc.). Mistaken for somnambulism, they are not treated. What are the differences? The epilepsies may appear at different hours of the night, or while falling asleep, they may occur repeatedly during the same night, the behavior is stereotyped and there is no recollection on the following day or when waking up. Waking up tends to be arduous, with pain through the body, headaches or confusion. Epilepsies can appear in children, adults, in the elderly, and some of them can even be familiar.

Other cases, while classically appearing mostly in elderly men, are the REM behavior disorder. What is this? It includes episodes that occur in a dream context, during which someone is attacking either the patient or a relative. The patient defends himself and, in that dreamy defense, violently assaults who’s closest, jumps from the bed as if he were flying, etc. When he wakes, with some difficulty, often because someone is screaming or because he injures himself, he stumbles upon what he has caused and shivers: blackened eyes, strangled necks, blood and gore, broken arms, etc. Those who suffer from this usually are peaceful and sane, and isn’t expressing violence in any way, on the contrary: was rather defending himself from it.

What happened? Dreams where he is the victim of violence, and during which he did not have the classical, normal and protective REM atonia, that transiently paralyses us, and he executed exactly what he was dreaming about.

Both epilepsies and REM behavior disorder require an efficient and urgent treatment, by Sleep Medicine specialists or Neurologists. Somnambulism, in most cases, requires protective and prophylactic measures.

Therefore, never mistake one for the others, because most of the times walking around while asleep is not sleepwalking. 

Professor Teresa Paiva,

Lisbon April 26^th 2013