Alien Hand Syndrome

Alien Hand Syndrome (AHS) is a condition that involves uncontrollable hand or limb movement. Named after the title character in the classic 1964 film, the syndrome is also called Dr Strangelove syndrome. The afflicted person experiences his or her limb acting involuntarily, i.e., without conscious control; and therefore, when one hand is engaged, the other hand would begin and do something counter to the former. The person with AHS may sometimes reach for objects and manipulate them without intending to do so, even to the point of having to use the other hand (normal one) to bring the alien hand under control. AHS may occur in cases of tumor, stroke, or surgery affecting the corpus callosum, which connects the two hemispheres of the brain. It may also present in cases where a person has had the two hemispheres of their brain surgically separated—a procedure performed in extreme cases of epilepsy and epileptic psychosis to allay the symptoms. While damage to the left hemisphere of the brain affects the right hand, damage to the right hemisphere affects the left hand because each side of the brain controls movement on the body’s opposite side.