Could these brain changes explain phantom limb?
New research could help to explain why some people report that they experience sensation in a missing limb, following amputation.
Phantom limb is the sensation that the missing part remains attached. The vast majority of people with amputation report phantom sensations, often with pain.
Now, an imaging study from two research centers in Rio de Janeiro in Brazil has pinpointed certain changes in functional connectivity — or how brain areas communicate — that can follow limb amputation.
The changes occur in the sensorimotor areas, which are the parts of the brain that process touch and other sensory signals and control movement.
The researchers found two main changes in functional sensorimotor connectivity. One affected communication between the left and right sides of the brain, and the other affected only the side of the brain that lay on the opposite side of the body to the amputation.
The journal Scientific Reports has recently published a paper on the findings.
"The brain changes in response to amputation," says first study author Ivanei E. Bramati, who is a medical physicist at the D'Or Institute for Research and Education in Rio, "have been investigated for years in those patients who report the phantom limb pain."
"However, our findings show that there is a functional imbalance, even in the absence of pain, in patients reporting only phantom sensations," he adds.
