The phantom limb and mirror box therapy

The Ghost member, term entered Silas Weir Mitchell In 1872, he refers to a syndrome suffered by some people who have lost an arm, a leg or an organ and who continue to experience the sensations of amputated limbs.

Patients who suffer from this syndrome feel as if they are making a gesture, feel itching or intense pain.

The brain and the body

According to the neurologist of the Brain and cognition center from the University of California, San Diego, Vilayanur S. Ramachandran, nearly 70 percent of amputees continue to experience intermittent pain in the missing limb even decades after being amputated, producing devastating consequences in the lives of patients that suffer.

Unfortunately, for many years, the treatment had been ineffective because its biological bases were not sufficiently clear. Phantom limb sensations may appear immediately after limb amputation or late, but pain usually appears in the first week after postamputation. It usually evolves with a reduction in both the frequency and the pain crises, but sometimes the pain can persist for years. In addition, it should be noted that phantom limb syndrome can cause psychological disorders such as

depression, anxiety or stress in those who suffer it.

What is the cause of phantom limb syndrome?

There are several theories that try to explain the cause of the phantom limb. Not long ago there was a simple and unambiguous relationship between injury and pain, but a current of thought recently has located the genesis of the phantom limb in the brain since the cognitive and affective.

Investigations of Ronald melzack gave rise to the neuromatrix theory, in which the diffusion of pain and its transmission through the body are attributed due to a complex system in which various areas of the system intervene central and peripheral nervous, autonomic nervous system and endocrine system, directly influenced by various psychological, emotional, genetic and social. This theory explains that we can feel sensations of pain in the body caused from within, that is, from our own organism, and through this system we ourselves can make these sensations increase, modify or decrease in a moment determined. If this matrix is ​​activated in the absence of peripheral sensory information (amputated limb), it would produce the sensation of having a limb present after the loss.

Another line of research is that of the scientist Ramachandran, that in his book "Brain ghosts"He gives an amazing explanation. A patient with a phantom limb complained of itching in his missing hand. Doctor Ramachandran, with a cotton swab for the ears, scratched the patient on the face relieving the itchiness of his hand. What is the explanation for this? The explanation is found in the Penfield homunculus. In the 1950s, Penfield and Rasmussen demonstrated the existence of a cortical map of body representation in two aspects: motor and somatosensory.

East Neurological map has particular characteristics: each part of the body is represented according to its sensorimotor importance (for example: the lips or hands have more cortical representation than the trunk, so they are more sensitive), that is, one thing is the body and another is the representation of the body in the brain. If a person loses a leg, an arm or an organ, the representation of him in the Penfield homunculus ceases to be receive information from that effector, but then that area of ​​the map can be invaded by the representation adjacent. In the case of the amputated hand, the adjacent representation is that of the face. In this way, stimulation to the face can make a hand (phantom) feel.

Mirror Box Therapy

This seems to demonstrate the plasticity of the brain, but what about phantom limb pain? Most patients, after an accident, are left with a useless and sore arm. After limb amputation, pain usually persists. Ramachandran think that the basis of this phenomenon is found in the learned paralysis, since the phantom limb also lacks mobility and the brain remains fixed on the idea of ​​an arm without movement. To do this, the neurologist invented the mirror box.

The mirror box is a box with a mirror in the center, when the patient introduces the arm without amputating, he can see the reflection of his arm in the mirror. When he sees his arm, he feels that the limb is present despite being amputated. The patient then moves the arm, and through the use of the visual feedback and by eliminating potentially painful positions, manages to give feedback to the brain and relieve the pain you feel. Sometimes even the phantom limb disappears.