In a recent accident, your favorite uncle lost one of his arms just below the elbow; he sustained no other injuries. The wound has completely healed, yet he is plagued by pain he claims is coming from a hand that is no longer there. Afraid to confide in his doctor, he asks you if he is going insane. What should you tell him? What principles are illustrated by this phenomenon?

phantom pain

Explanation:

I would tell him about the condition and its name and available treatment. I will do this by describing the name of the condition. This is known as phantom pain. This occurs after maybe having part of the arm or leg amputated. There is a chance you could feel pain in the limb that's no longer there. This occurs mostly in arms and legs and about 80-100% of amputated patients experience this. The cause of it is not yet clear as it can be as a result of the contribution of some damaged nerve endings, scar tissue at the region of the amputation process and the physical memory of before-amputation pain in the affected area. There are also medications to be used to treat this condition and some do go away on its own.

he has fantom pain and that he isn't crazy. when he lost his arm below elbow, the pathway to hand had been severed and the brain still thinks the pathway is going to his hand

Explanation:

Your uncle still has the surviving parts of the sensory pathway that once served the entire arm. This mayinclude the primary sensory neurons, since the severed axons could have regenerated (but even if thesecells degenerated, the remainder of the pathway did not). Anything that stimulates the sensory nerve inthe stump may cause signals to go to the area of the cerebral cortex that once received inputs only fromthe hand. Your uncle is not crazy, rather he is experiencing phantom limb pain, which is very real. Thisphenomenon illustrates labeled line coding and coding of stimulus location.