In one of Stanley Kubrick’s weirdest movies (even by Kubrick standards), “Dr. Strangelove or: How I Learned to Stop Worrying and Love the Bomb (1964)“, one of the characters played by Peter Sellers is tormented by the irresistible and convulsive urge of lifting his right arm in a Nazi salute. He can’t control it, it’s like it has a mind of its own. In most respects, the movie is hilarious if you have taste for cynical and exaggerated humour. What’s far from being hilarious is the real life condition that plagues some people. Yes, there are some people out there who can’t control one of their hands – the phrase “a mind of its own” is no figure of speech for these individuals. In popular literature this conditions is referred to as the alien hand syndrome.

Imagine sitting in line at your local convenience store and all of a sudden some guy starts pinching you for no reason, only for the guy to immediately start punching his arm with his other, while frantically apologizing “sorry, sorry. I can’t control it! Sorry!”. Cases have been reported – although its difficult to attribute to alien hand syndrome or some conscious action taking advantage of the condition – in which the alien hand would grab a nearby breast or start masturbating, with little to any control from the ‘hand owner’. These are deepening embarrassing situations, but it’s even frightening to hear accounts of people being attacked by their own alien hand, which is actually no longer their own to call.

Scientists describe it as a “complex, goal-directed activity in one hand that is not voluntarily initiated,” and unfortunately due to the rarity of the phenomenon, it is yet poorly understood. What we know for certain is that it’s due to some malfunction in communication between the two hemispheres of the brain. For instance, the alien hand is always in the non-dominant half. If a person is right handed (left hemisphere dominant), then almost always the left hand (controlled by the right hemisphere of the brain. In this case non-dominant) will be the one at risk of becoming alienated.

Though it may occur due to a naturally occuring brain dysfunction, most of the cases surface following brain surgery, namely after some patients had their corpus callosum sectioned – the band of nervous fibres which keeps the two halves of the brain in constant contact. This radical procedure is used as a last resort to treat epilepsy patients. Sometimes, however side effects may include losing one’s non-dominant hand, leaving it to the control of an impulsive and unconscious part of one’s brain.

‘I can’t make it listen to me!’

55-year-old Karen Byrne from New Jersey had such a procedure performed on her brain, after battling epilepsy for as long as she could remember. She was cured, but now she faces another torment.

“Dr O’Connor said ‘Karen what are you doing? Your hand’s undressing you’. Until he said that I had no idea that my left hand was opening up the buttons of my shirt.

“So I start rebuttoning with the right hand and, as soon as I stopped, the left hand started unbuttoning them. So he put an emergency call through to one of the other doctors and said, ‘Mike you’ve got to get here right away, we’ve got a problem’.”

And more.

“I’d light a cigarette, balance it on an ashtray, and then my left hand would reach forward and stub it out. It would take things out of my handbag and I wouldn’t realise so I would walk away. I lost a lot of things before I realised what was going on.”

Extreme cases have occurred where the hand has attacked, and even tried to strangle with a cord, the person to which it’s attached.

What happens here: the nervous band that connects the two hemisphere being sectioned, communication between the halves of the brain becomes deleterious. In a normal, healthy brain the two halves coexist peacefully and share functions which are asymmetrically located, although physically the brain is symmetrical. What these cases potentially reveal however is that each half of our brains contain separate consciousnesses.

Two hands, two brains, two wills

In one experiment, neurobiologist Roger Sperry asked a participant who had his hemisphere split through the same surgery to perform a puzzle, which implied rearranging blocks so they matched the pattern on a picture. The person in question was left handed, meaning his right hemisphere was dominant. When attempting to complete the puzzle using his left hand only, the man was making good progress. When asked to perform the same task using his right hand, surprise; he had no clue what so ever where to begin and what to do next. The participant then tried using his left hand, the hand that could actually start fitting at least two pieces of the puzzle, only to have his right hand block it – the hands were actually fighting each other. Experiments like this led Sperry to conclude that “each hemisphere is a conscious system in its own right, perceiving, thinking, remembering, reasoning, willing, and emoting”. Powerful!

Sadly, there is no cure for the alien hand syndrome, yet some people manage to control their hands to a degree, but even then with great difficulty and imprecision in actions. For instance, while trying to touch the tip of the nose, they touch the shoulder instead. Most people suffering from the syndrome have learned that keeping their alien hand occupied (holding a cane) will offer them some peace for a time. What this startling condition reveals, in truth, is that there might be two personalities nested inside each of us.

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