automatism

Automatism refers to actions performed without conscious volition or awareness, often arising from disturbed mental states or external stimuli. The term is used in both legal and medical contexts, though with different emphases: in law it concerns whether an act was involuntary and thus not punishable as a crime; in medicine it refers to automatic behaviors or cognitive processes that occur with reduced awareness.

In criminal law, automatism is typically divided into external (non-insane) automatism and internal (insane) automatism. External automatism results from an external factor that overrides voluntary control, such as sleepwalking, a concussion, hypnotic trance, a seizure, or intoxication. When the act is truly involuntary, the defendant may be acquitted. Internal automatism stems from an internal factor, typically a mental disorder, and is treated as insanity; verdicts often lead to hospital treatment rather than discharge.

In psychiatry and neurology, automatism describes automatic or semiautomatic actions carried out with little or no conscious awareness. Temporal lobe epilepsy, for example, can produce automatisms such as lip-smacking, dazed wandering, or mumbling during seizures. Other forms occur in dissociative disorders, where a person carries out complex actions with impaired recall of the event. Automatism can involve memory gaps about the act and may be triggered by medication, stress, or hypnosis, but it is not itself a disease.

Because the concept spans legal and medical domains, assessment and outcomes differ accordingly. Legal determinations focus on voluntariness and mens rea, while medical evaluations emphasize underlying causes, such as seizure control, dissociation, or stress-related conditions, and appropriate treatment.