agrability University

Blogging with Becky

When we visit a farmer with an amputation it doesn’t take long until they mention phantom pain sensations. After a part of the body, like an arm or leg is amputated by an accident or from surgery, the person sometimes feels that the arm or leg is still there. Phantom limb pain may occur because the brain sends signals to a missing limb as if it were still there but doesn’t get feedback and keeps resending and amplifying the signals.

Many people with amputations have a sensation that they are able to ‘move’ their missing limbs voluntarily but others experience the missing limb as ‘paralyzed’ in a painfully awkward position. Until recently, the only remedy was a series of strong medications. New approaches, based on a better understanding of the brain’s role in pain, are opening the way for more innovative treatments.

Dr. V.S. Ramachandran, a researcher at the University of California, San Diego, devised a seemingly simple experiment to explore phantom pain. One of Ramachandran’s patients complained that he was suffering from an excruciating cramping in his phantom arm. He felt that his phantom hand was clenched so tightly, he could feel his fingernails digging into his phantom palm. Ramachandran came up with an unusual treatment. He placed a mirror in a cardboard box and instructed the patient to place his existing hand inside the box, next to the mirror. When the patient looked down at the mirror, the reflection of his existing hand stood in as a visual replacement of his phantom limb. The patient was told to imagine that the reflection was in fact the lost limb, and to practice clenching and unclenching his hand while looking in the mirror. To the patient’s surprise — and Ramachandran’s — the illusion worked. After two weeks, the patient’s pain vanished, along with his perception of a phantom arm. Other researchers are looking at virtual reality video games that are based on the same concept of the mirror therapy. The video games give a person the perception that their missing limb is still there. These therapies are also effective for stroke victims. Click here for more information.

Below are two videos from YouTube that are portions of a BBC special entitled “Phantoms in the Brain”