It’s like something straight out of a horror movie. You wake up in the middle of the night. You can’t breath. Someone is strangling you, trying to choke the life out of you. Desperately, you attempt to fend off your attacker, only to find that you can only fight back with one hand. You turn on the lights and discover their identity, only to discover it is yourself. More specifically, your other hand. With vigor it squeezes at your windpipe until, just as suddenly as it had started, it stops.
No, you haven’t been teleported into Sam Raimi’s horror classic, The Evil Dead. And no, you’re probably not possessed. But the answer, while a bit more mundane, is equally mysterious. It’s called Alien Hand Syndrome, and, to a growing number of Americans, this nightmare is becoming a terrifying reality.
Alien Hand Syndrome, or more mundanely referred to as Anarchic Hand Syndrome, is a rare condition in which the sufferer loses awareness and control of one of his or her hands. The hand then behaves erratically, exhibiting random behavior. But instead of merely twitching or suffering muscle spasms, as is frequently associated with isolated paralysis, the rogue appendage begins to exhibit behavior that is far more unusual. The maverick hand seems to develop a mind of its own; instead of acting randomly, its actions seem to betray a complex intelligence, often allowing it to complete complicated actions, such as stroke or pat the owner affectionately, button or unbutton clothing, manipulate objects or tools, or, more sinisterly, strike out at the owner or other hapless victims within reach.
In some cases, the owner is entirely aware of the hands behaviors and retains full sensation in the limb. In these cases, the hand will behave normally most of the time and the owner will retain a degree of control, suffering occasional “attacks” of onset behavior with the hand, usually manifesting itself by grasping something without the knowledge or intent of the owner, such as a table edge, a door handle, or an object, sometimes not relinquishing it until it grows weak or the owner physically “peels” the fingers off. This is what has led some researchers to compare it to Parkinson’s disease. In these cases, treatment is relatively simple: simply give the hand a sustained activity, such as grasping something, to keep it occupied.
In other, more drastic cases, the hand’s behavior is far less easily managed and guided by far more alien designs.
While the hand works meticulously to an objective of its own design, the “owner” is completely unaware of its actions. Sensation is entirely lost in the appendage, and therefore it is frequently up to helpful observers to point out the peculiar actions of the alien hand. This can be socially awkward at best, or downright embarrassing or harmful to the owner at worst. Focused behaviors such as driving or operating machinery can be hazardous to those suffering from this rare dysfunction if not impossible.
The causes of this rare disorder are equally mysterious. While there is no clear origin of the hand’s peculiar behavior, there are a few common denominators amongst people afflicted with AHS. Usually the sufferer has had some former brain dysfunction, such as a stroke, epilepsy, paralysis, or even just peculiar spasms that have developed over time. Sometimes this condition develops after brain surgery, particularly if the surgery involves separating the hemispheres of the brain, altering motor control centers, or damage to the medulla oblongata.
What alarms some researchers, however, is the discovery of more and more of these cases cropping up across the world. Since the 1980’s, the number of documented cases of Alien Hand Syndrome has tripled. Who knows? Maybe one night soon you’ll wake up to find that your hand has joined the alien hand rebellion. And while the odds are statistically stacked against your hand developing a sudden urge to mildly inconvenience you or obtain murderous impulses (currently roughly one in 500,000), it never hurts to keep a chainsaw handy. Just make sure you can use it one-handed.