Using functional magnetic resonance imaging (fMRI) and a "cyberglove" to record brain changes during motor activities, researchers demonstrated that people can learn to remap, or redirect, motor commands. This is an important step in stroke recovery and in training strategies for brain-machine interfaces--conduits between the brain and artificial limbs.
"For stroke patients and others who have a brain deficit, coordinating what they see with body movement is very difficult," said the study's lead author Kristine Mosier, D.M.D., Ph.D., assistant professor of radiology at Indiana University in Indianapolis. "The brain must remap or relearn the process of matching visual input with sensory input. Our study demonstrated that individuals can learn to remap motor commands."
When neurons--the primary cells of the nervous system that make all thought, feeling and movement possible--are damaged by a stroke or brain injury, other neurons take over for them. But until now, scientists weren't sure which neurons compensated for damaged neurons, or how the brain cells learned their new jobs.
Dr. Mosier's study simulated a learning problem by having 17 healthy adults wear a synthetic glove with fiber-optic cables on their dominant hand. The glove translated hand movements into signals, which were sent to the computer and transformed into the two-dimensional position of a cursor on the computer screen. The subjects were then asked to align the cursor with 50 different targets while researchers used fMRI to observe which areas of the brain controlled the intricate movements of the hand.