Our brain maps out our body to facilitate accurate motor control; disorders of this body map result in motor deficits. For a century, the body map has been thought to have applied to all types of motor actions. Yet scientists have begun to query how the body map operates when executing different motor actions, such as moving your eyes and hands together.

A recent research paper has revealed that the body relies on multiple maps based on the choice of motor system. Details of the research were published in the journal Proceedings of the National Academy of Sciences.

Patients with motor dysfunction have abnormalities in their hands and feet that are felt in the brain. Traditional rehabilitation takes in to account the physical dysfunctions. But recovery of the neurological aspects is not visible and subjective.

To reveal more behind our body map, the authors organized an experiment where participants were instructed to point to various parts of their right hand with the index finger on their left hand whilst simultaneously following with their eyes. This enabled to measure the mind's perception of the right hand for the eyes and the left hand movements.

Even though the eye and the left hand were pointing to the same spots, the imaging from the pointing was more distorted, demonstrating the existence of a separate body map.

The author expects his findings to contribute to the development of new diagnostic techniques for motor dysfunction. "Today, Japan's population is aging rapidly, so we are experiencing a sharp increase in the number of patients with motor dysfunctions. Better understanding of how patients' bodies are perceived by their minds will help to build a more effective rehabilitation technique."

http://www.tohoku.ac.jp/en/press/reinterpreting_our_brains_body_maps.html

https://www.pnas.org/content/119/4/e2112318119

http://sciencemission.com/site/index.php?page=news&type=view&id=publications%2Fmultiple-representations&filter=22