In Chapter 7, Doidge introduces us to an M.D. whose specialty is neurology, but who also has a Ph.D. in psychology. Though from India, Ramachandran directs the Center for Brain and Cognition at the University of California in San Diego. Using simple devices “Rama” has discovered the secret of phantom limbs and chronic pain. Some people suffer pain even after organs have been removed. “Normal pain, ‘acute pain,’ alerts us to injury or disease by sending a signal to the brain saying, ‘This is where you are hurt – attend to it.’”(p. 180) When the nerves themselves are damaged ‘neuropathic’ pain results with no known cause.
Reading the work of Tim Pons and Edward Taub regarding mind mapping monkeys, Ramanchandran wondered if neuroplasticity would explain phantom pain. “Rama” worked with a 17th year old amputee. First, by blindfolding the young man and then with brain mapping (magnetoencephalography), he was able to determine that the brain map for his phantom arm and face had merged. Some relief was enjoyed by satisfying an itch in the phantom arm by scratching his face. Taub’s team and others have confirmed “Rama’s” conclusion. All of this is so unpredictable because brain maps are dynamic and always changing. “He thinks one reason people get phantom pain is that when a limb is cut off, its map not only shrinks but gets disorganized and stops working properly.” (p. 183)
Other sensations experienced by amputees include the memory of the explosion at the time of injury or pleasant sensations from other body parts or even “frozen” body parts (arms in slings at the time of injury).
Ramachandran then asked himself if these phantom sensations could be “unlearned.” His idea was to fight one illusion with another. By using an open box separated by a mirror an amputee was able to “amputate” the phantom limb. After looking at the mirror image of the phantom limb during 10 minutes a day for 4 weeks, the phantom limb disappeared.
This “body image” extends to other areas. Anorexics imagine they are fat when, in fact, they are near starvation. Others imagine something about their bodies to be wrong. Instead of plastic surgery, they need “’neuroplastic surgery’ to change their body image.” (p. 188) Contrary to conventional wisdom “Rama” believes that pain and body image are created by the brain and projected onto the body. Mothers soothing children and the placebo affect may very well turn down the brain’s pain production. “Ramachandran and Eric Altschuler have shown that the mirror box is effective on other nonphantom problems, such as the paralyzed legs of stroke patients. Mirror therapy differs from Taub’s in that it fools the patient’s brain into thinking he is moving the affected limb, and so it begins to stimulate that limb’s motor program.”(p. 195)
Remarkably, the work of neurologists has opened up more understanding of the WONDER of God’s creation, the brain. We have so much more to learn. Do you agree that pain is the dark side of plasticity?
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