Psychologists believe that the most probable reason for this condition is some kind of conflict between the left and right parts of the brain. Subsequently, the person believes that their hand is some kind of a foreign object.
It has even been reported that the hand confronts the will of its owner. It is if the arm has the mind of its own.
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It is a condition where the mind of the sufferer creates false memories. A person believes in these memories so firmly, and often times would go to the great lengths just to prove that they are true and not just product of their mind.
Psychologists found that confabulation can be caused by dementia and Alzheimer, but it can also be caused by the memory loss caused by heavy drinking.