Alien Hand Syndrome may sound like something from a sci-fi movie, but it’s a very real (and rare) neurological condition.
People with AHS experience involuntary hand movements that feel completely separate from their own intentions, almost as if the hand has a mind of its own.
While it sounds unusual, it’s a medically recognised condition often linked to brain injuries, surgeries, or neurological disorders.
Let’s take a closer look at what causes this condition, what it feels like, and what science says about it.
Alien Hand Syndrome Explained
Alien Hand Syndrome is a neurological disorder in which one hand functions involuntarily, performing purposeful movements without the individual’s conscious intent. The person is aware that the hand is their own but feels like it behaves autonomously. This can lead to confusion, frustration, and even fear.
AHS typically affects the non-dominant hand and is most commonly associated with brain injuries or surgeries, especially those involving the corpus callosum (which connects the two hemispheres of the brain), frontal lobes, or parietal lobes.
Signs of Alien Hand Syndrome
This disorder was first documented by Dr. Hugo Liepmann in 1908. He observed a female patient having involuntary movements in the left hand, trying to strangle herself. This incident started after she suffered a stroke.
After studies, it was found that it is a neurological disorder, not a mental illness or psychological problem. It mainly affects the left hand.
A person with AHS might exhibit the following symptoms:
- Involuntary limb movements: At times, the hand (or the leg) will move, reach for objects, or do anything without the person intending to do so.
- Poor hand coordination: It can be difficult to perform tasks that require the coordination of both hands, such as zipping a jacket, tying a shoe lace, or doing the dishes.
- Having a feeling of alienation with the hand: The affected hand might feel like it does not belong to you or seem to have a mind of its own.
Along with these symptoms, the person will feel:
- Weakness in the hand
- Not able to recognise the texture of the object being touched
- Difficulty understanding sensory signals from the affected/alienated hand
Alien Hand Syndrome Causes
This neurological disorder happens when there is damage to the part of the brain that is responsible for limb movement and awareness. The causes are elaborated below:
Brain Surgery
People who have had brain surgery, corpus callosotomy, after epilepsy, are often afflicted by this condition. In this surgery, the connection between the two brain hemispheres is cut off to prevent seizures. As a downside, this can also cut off the brain’s command connection to one hand, causing it to work independently.
Stroke
When the stroke affects the parts of the brain like the parietal lobe, frontal lobe, or corpus callosum, it can lead to AHS. All of these areas of the brain help with body movements.
Brain Tumours or Aneurysms
Tumours or aneurysms (abnormal bulges in the blood vessels) in the brain can disrupt the nerve connection and hinder limb movement. This can lead to disruption of motor or sensory pathways, and thus AHS.
Neurodegenerative Diseases
According to an NCBI study, Issues related to cognitive decline, such as Alzheimer’s disease, Creutzfeldt-Jakob disease, or corticobasal syndrome, can lead to alien hand syndrome, inducing a feeling of foreignness with a limb.
Alien Hand Syndrome Cure
There is no cure for this syndrome because it is caused by damage to certain parts of the brain that can not be undone.
However, several strategies, as listed below, can help manage the symptoms or make the person feel more at ease with this disorder:
Mirror therapy
This therapy uses visual feedback to retrain the brain into thinking that the movement was caused voluntarily by you and to accept it as a part of your body.
Botulinum Toxin Injections
These injections can temporarily prevent muscle movement in the affected area. This can be useful in preventing limb movement, and its effect lasts for 3 to 4 months.
Cognitive Behavioural Therapy (CBT)
CBT or occupational therapy can help individuals change negative thinking patterns and improve daily functional activities. These therapies are used as coping mechanisms and do not treat the condition.
Clenching an Object
Giving the alien hand something to hold, such as a stress ball or a soft object, can reduce involuntary motion.
Read More: Effective Carpal Tunnel Syndrome Treatment: Your Path to Pain-Free Hands
To Sum Up
Alien hand syndrome is a neurological condition in which a person’s hand acts independently. It is a rare disorder affecting only a small number of people. It is caused by the damage in some parts of the brain due to surgery, stroke, tumours, or neurodegenerative disease. Although there is no cure, several therapies and behavioural tricks can help reduce and cope with the symptoms.
