The ability to sense our environment is something that many of us take for granted. It's the simple, general things that we encounter every day; this pillow feels soft, the concrete is hard, snow is cold. But what if you were feeling things with a part of you that wasn't there?
No, this isn't something from a science fiction show, it's a real disorder that often occurs in amputees called phantom limb syndrome. And it's more common than you probably think; 80 percent of amputees will experience this phenomenon at some point.
The symptoms are very straight forward – if a person can feel something from a part of the body where a limb is not present, then they have phantom limb. The types of sensations are divided between non-painful and painful. Non-painful sensations are very much like the feelings described above. They can range from feeling differences in temperature to itching. The latter subdivision includes pains such burning and prickling.
The painful feelings are unfortunately the most common sensations related to phantom limb syndrome. Oftentimes the pain is intrusive and debilitating. It can severely interfere with daily life and is difficult to effectively cure.
Normally the body is able to interpret sensations through sensory receptors under the skin. These receptors create electrical signals that are able to be carried from the peripheral nervous system to the central nervous system, where it can be interpreted and responded to accordingly.
Amputees obviously do not have these receptors. So what’s triggering the brain’s response?
Scientist Vilayanur S. Ramachandran believes that the syndrome has something to do with neurons changing connections in the brain (a process called neuroplasticity). Basically, certain sections of the brain are used for specific areas of sensory input. When area is lacking any sort of stimulation because of the amputation, other parts of the brain are connected to this area.
For example, in one of Ramachandran’s experiments he discovered that an arm amputee was receiving signals from sensory receptor in the face. The section of the brain used for interpreting messages from the arm was not receiving any input, so neurons connected to the sensory receptors for the face.
A very basic form of relief for those that suffer from the painful effects of phantom limb is pain medication. Of course this is not very helpful for those that suffer from non-painful effects and even those on medication may not fully be pain free.
An interesting outlet for relief can be found in a very specific type of acupuncture. This traditional medical technique has been used for thousands of years for a variety of ailments and disease. In phantom limb specifically, a small, precise prick of the ear has been known to alleviate pain. There are also a few pin pricks on the scalp, but the ear is the key. This treatment is usually supplemental to medication.
A newer treatment that is now commonly associated with phantom limb relief is mirror-box therapy. It requires patients to insert their intact limb in a box with a mirror where they cannot see their amputated limb. The effectiveness is questionable, but has been noted to help at least 60 percent of patients in two different studies.