Alien Hand Syndrome

Alien Hand Syndrome sounds like a funny name for a disorder in humans but it is the most intriguing one! The term alien means something that is foreign and does not belong to oneself. So Alien Hand Syndrome by that definition would mean the syndrome where the hand feels foreign to the host body and that’s exactly what it is. To put it simply, the person loses control of one of their hands which lets it act on its own accord in a fashion alien to the host body. Sounds perplexing, doesn’t it?


AHS is also anarchic hand. When a person suffers from epilepsy, Alzheimer’s, stroke, or any other brain surgeries which lead to the separation of both the hemispheres of the brain, they’re at risk for Alien Hand Syndrome or AHS. Due to the surgery, the communication between both hemispheres is damaged which leads to a lot of miscommunication due to which the signal for movement just reaches from one-half of the hemisphere to the hand, the rest of the body is unaware of this command. This leads to involuntary gasping, choking, shaking the hand. Usually, it is the left hand that is affected by this disorder as the majority of the people are right handed. AHS is prominent in the less dominant hand.

AHS presents itself in a way that the patient needs to hold or grab everything in their vicinity and this is out of their control. The bilateral frontal lobe is damaged which leads to the body responding to external stimuli rather than internal ones. For example, seeing a toothbrush or a mug would be connected to holding it to brush your teeth or drink your coffee so the hand responds to this external stimulus rather than the one that reasons and stops the hand from grabbing it.

AHS is not as creepy as it sounds.

Some of the symptoms are:

  1. Lack of awareness of arm movement or actions
  2. Lack of control over arm movement
  3. Inability to feel control over hand(s) movements

There is no treatment for AHS except for ways of getting around it like by keeping the “alien” hand busy by making it hold an object at all times. It is very difficult to recognize this as it usually doesn’t have severe symptoms. The host body also tries to restrain the alien hand during times of movement, by holding it tightly, thus restraining it. In very bad cases, the alien hand tries to choke the host body or someone in front of them which brings in a lot of shame and guilt but otherwise, AHS is difficult to diagnose and more difficult to treat.

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