Alien Hand Syndrome

Alien Hand Syndrome is defined as the feeling you get that your hand is being possessed by a force outside your control. It often comes about following a trauma to the brain, after brain surgery or after a stroke or brain infection.

Affected people generally have feelings in the hand, but believe that it is not part of their body, and thus that they have no control over it - such that it belongs to an alien.

This paper outlines the origins and neurology of the condition, with some early observations.

The authors take us back to the famous Stanley Kubrick film Dr Strangelove, where the main character shows a bizarre movement disorder. His hand seems to have a life of it’s own, once saluting under it’s own will and even clutching at his own throat while he restrains it with the other hand.

Although this seems a bit far-fetched, it’s in fact not all that far from the truth, and the disorder (a type of neurologic disease) is often called alien hand syndrome.

The movement of a limb without the person’s intention is quite alarming and frustrating of course, and patients can find themselves snatching at objects and not being able to let go of items in their grasp or trying to pry objects out of their grip with the other hand.

Hand(y) facts:

The phrase “rule of thumb” apparently comes from an old English law, which stated that you could not beat your wife with anything wider than your thumb. However, it may be older than that, and come from Rome, when gladiators’ fates were decided using the thumb up or down.

The phrase “to win hands down” comes from horse racing, where a jockey who is on the way to a comfortable win would lower his hands, thus allowing the horse to run on without his control.

An ant will always fall over towards its right hand side when drunk.

[Biran, I. and Chatterjee, A. (2004). Alien Hand Syndrome. Archives of Neurology 61, 292-294. ]