Tuesday, January 18, 2011

Phantom Limb

Sri.Sridharan, one of the trustees of Krishnamacharya Yoga Manidram, after reading my blog post regarding “Unlocking the Brain’s Secrets” has given an allied topic with an additional thread for this article. Dr.Ramachandran who has presented this paper has come out with an another article called “Phantom Limb”.
A phantom limb is the sensation that an amputated or missing limb (even an organ, like the appendix) is still attached to the body and is moving appropriately with other body parts. Approximately 60 to 80% of individuals with an amputation experience phantom sensations in their amputated limb, and the majority of the sensations are painful Phantom sensations may also occur after the removal of body parts other than the limbs, e.g. after amputation of the breast, extraction of a tooth (phantom tooth pain) or removal of an eye (Phantom eye syndrome). The missing limb often feels shorter and may feel as if it is in a distorted and painful position. Occasionally, the pain can be made worse by stress, anxiety, and weather changes. Phantom limb pain is usually intermittent. The frequency and intensity of attacks usually decline with time.
A slightly different sensation known as phantom pains can also occur in people who are born without limbs and people who are paralyzed. Phantom pains occur when nerves that would normally innervate the missing limb cause pain. It is often described as a burning or similarly strange sensation and can be extremely agonizing for some people, but the exact sensation differs widely for individuals. Other induced sensations include warmth, cold, itching, squeezing, tightness, and tingling.
 Dr. Ramachandran reasoned that if someone were to lose their right hand in an accident, they may then have the feelings of a phantom limb because the input that normally would go from their hand to the left somatosensory cortex would be stopped. The areas in the somatosensory cortex that are near to the ones of the hand (the arm and face) will take over (or "remap") this cortical region that no longer has input. Ramachandran and colleagues first demonstrated this remapping by showing that stroking different parts of the face led to perceptions of being touched on different parts of the missing limb. Through Magnetoencephalography (MEG), which permits visualization of activity in the human brain, Ramachandran verified the reorganization in the somatosensory cortex.
Yesterday there was a concert by Sri.S.R.Krishnamurthy in "Naadha Neeranjanam" of TTDevasthanam Doordharshan Channel. Kindly read more on his achievements as a musician. Immediately after seeing him and this topic my mind started exploring the possibilities of his physical and mental stress while singing.