Alien Hand Syndrome: Causes and Effects

Alien Hand Syndrome or AHS is a neurological disorder that causes the patient's hand to move involuntarily. The individual has no control over the movement of the hand and sometimes, he or she may not even be aware of the action! The patients often report feeling like their hand does not belong to them anymore. The disease has no cure but the symptoms can be treated and reduced. Usually the hand is kept occupied constantly by holding a light object. 

Causes of Alien Hand Syndrome: 
Though the exact causing factor of AHS is unknown, there are a number of instances which have been shown to influence the development of the condition. The chief factors are: 

1. Brain injury: Injury caused to the brain by blunt force trauma or faulty surgery can lead to Alien Hand Syndrome. This is particularly seen if the frontal lobe (the brain center of voluntary movement) or the corpus callosum (the bundle of nerve fibers connecting the left and right hemispheres of the brain) is affected. These are the areas that regulate motor functioning and the neural pathways to execute the actions. 
2. Brain tumor: A tumor (a mass of abnormal cells) pressing on the motor centers of the brain can cause involuntary movements of the left hand in a right handed person. This is because the right hemisphere of the brain controls the left side of the body and vice versa. Tumors blocking the neural pathways usually cause errant movements of the predominant hand. 
3. Neurodegenerative conditions: Diseases like Alzheimer's disease and Creutzfeld & Jakob Disease are characterized by memory loss, rapid changes in personality and growing defects in the central nervous system. AHS could be a complication of such disorders. Effects of Alien Hand Syndrome This is an extremely rare condition. There have been less than 80 known cases around the world since 1908. 

The disorder is often unreported because it is mistaken for a psychiatric problem due to its unusual symptoms and effects. 

1. The patient may not even be aware of what his 'alien hand' is doing. The hand may even begin functioning of its own accord when the patient is asleep. 
2. AHS can result in feelings of guilt and shame because of the embarrassing actions of the hand that the patient has absolutely no control over. The hand is often said to be governed by primal animalistic urges of hitting others, tearing clothes off etc. 
3. The condition often leads to social anxiety, depression and paranoia.