In the U.S. alone, nearly 3 million people – many of whom are seniors – face limited mobility due to a stroke or amputation, according to statistics from the Centers for Disease Control and Prevention, and the Amputee Coalition. While current rehabilitation efforts have been effective in helping many of these individuals regain motion and flexibility, scientists hope that new studies will assist in the development of methods that go even further in bringing them back to full speed.
According to News Medical, researchers at the University of Missouri were particularly concerned about patients of stroke and amputees who lost the use of their dominant hand. The source noted that, in such cases, people have to adapt to using their non-dominant limb for day-to-day tasks, many of which require a great deal of precision.
Imagine a right-handed person having to learn – much later in life – to use their left hand for skills such as writing and drawing. Scientists recognized in such patients a need for more specialized rehabilitation methods. They analyzed not only the physical limitations that individuals in this condition face, but also how their brain responds to adaptation attempts.
Patients were asked to complete a simple drawing task while researchers observed them for speed and accuracy. The task was also performed while the individuals underwent fMRI scans, to determine their mental reaction as well. According to the scientists' results, the brains of people who had experienced a stroke or amputation adapted to compensate for the use of a non-dominant hand. Parts of the cranial system formerly used for motor and sensory functions helped make up the difference.
"We found that when amputees were forced to use their nondominant hands for years or decades, they exhibited performance-related increases in both the right and left hemispheres," said Scott Frey, director of the University of Missouri Brain Imaging Center. "This compensatory reorganization raises the hope that, through targeted training, non-dominant hand functions can be vastly improved, enabling a better quality of life for those who have lost dominant hand functions due to bodily or brain injury or disease."