Sleep-walking. (See SLEEP.)
n. sleep-walking: walking about and performing other actions in a semiautomatic way during sleep without later memory of doing so. It is common during childhood and may persist into adult life. It can arise spontaneously or as the result of stress or hypnosis; it may also be a side-effect of a hypnotic drug. —somnambulistic adj.
The performance of acts without conscious will, as, for example, after an attack of epilepsy or concussion of the brain. In such conditions the person may perform acts of which he or she is neither conscious at the time nor has any memory afterwards. It is especially liable to occur when persons suffering from epilepsy, mental subnormality, or concussion consume alcoholic liquors. It may also occur following the taking of barbiturates or PSYCHEDELIC DRUGS. There are, however, other cases in which there are no such precipitatory factors. Thus it may occur following hypnosis, mental stress or strain, or conditions such as FUGUE or somnambulism (see SLEEP). The condition is of considerable importance from a legal point of view, because acts done in this state, and for which the person committing them is not responsible, may be of a criminal nature. According to English law, however, it entails complete loss of consciousness, and only then is it a defence to an action for negligence. A lesser impairment of consciousness is no defence.... automatism
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