Ramachandran concluded that because Tom € cortex was no longer getting input from his missing hand, the region processing sensation from his face had slowly taken over the hand € territory. Ramachandran discovered that if he stroked Tom € face, Tom felt like his missing fingers were also being touched. Amputees sometimes experience phantom limb sensations, feeling pain, itching or other impulses coming from limbs that no longer exist.

Each part of the body is represented by a different region of the somatosensory cortex, and, as it happens, the region for the hand is adjacent to the region for the face. This kind of rewiring is an example of neuroplasticity, the adult brain € ability to change and remold itself. Ramachandran worked with patients who had so-called phantom limbs, including Tom, a man who had lost one of his arms.

The neuroscientist deduced that a remarkable change had taken place in Tom € somatosensory cortex. Our behavior and environment can cause substantial rewiring of the brain or a reorganization of its functions and where they are located. So touching Tom € face produced sensation in his nonexistent fingers.

Scientists are finding that the adult brain is far more malleable than they once thought.