A Secondary Network Discovered in the Brain
We have understood for years that the brain is plastic, not just as a child, but all through adulthood. Connections grow and change across all sections of the organ, and it can react to control a new bodily configuration with relative ease.
However, recently, neuroscientists found evidence of it changing with unsuspected speed. Their findings suggest that the brain has a network of silent connections that underlie its plasticity.
The brain's tendency to call upon these connections could help explain the curious phenomenon of "referred sensations," i.e. phantom limb syndrome, in which a person with an amputated arm feels sensations in the missing limb when he or she is touched on the face. Scientists believe this happens because the part of the brain that normally receives input from the arm, when starved of any input, starts opening connections, looking for data to process, and begins referring to the signals directed at the face, which are processed in an adjoining area of the brain.
The funny thing is, these new connections become established in a matter of seconds, which is too swift to be accounted for by cell growth - far too swift. Instead, it appears that there is a secondary network inside the brain, a sort of scaffold that interconnects different areas with entirely different processing purposes. Normally it is never used, but when one area is under capacity, it starts looking down this secondary network of deserted corridors, sending feelers for data to process. When it finds some, it pulls a copy back through into its own area and proceeds to process that data in established patterns.
"We found these referred sensations in the visual cortex, too," said senior author Nancy Kanwisher of the McGovern Institute for Brain Research at MIT, referring to the findings of a paper being published in the July 15 issue of the Journal of Neuroscience. "When we temporarily deprived part of the visual cortex from receiving input, subjects reported seeing squares distorted as rectangles. We were surprised to find these referred visual sensations happening as fast as we could measure, within two seconds."
It seems the brain is capable of reacting much more swiftly than anyone ever thought possible, to changes in the body configuration. The delay of weeks taken to learn how to use a change in bodily data suggests that the existing architecture of discrete sections is changed over time, from an area that handled the arm say, to the new area handling two arms. However, even if the area is not ready to process data in new ways, it is always eager to work, and has access to data access channels running throughout the brain, to try and find some.
It is possible then, that when we take the tack of giving people different bodily configurations via sensory robotics and VR, that their brains will adjust to the new limb and organ configuration, over time. Then, if they exit from the simulation after a long period of time exposed to the new body configurations, those areas will fall dormant, and start looking for data.
In short, phantom, phantom limb syndrome may indeed be possible.