Evaluation of robotic training forces that either enhance or reduce error in chronic hemiparetic stroke survivors.

@article{citeulike:552889, abstract = {This investigation is one in a series of studies that address the possibility of stroke rehabilitation using robotic devices to facilitate "adaptive training." Healthy subjects, after training in the presence of systematically applied forces, typically exhibit a predictable "after-effect." A critical question is whether this adaptive characteristic is preserved following stroke so that it might be exploited for restoring function. Another important question is whether subjects benefit more from training forces that enhance their errors than from forces that reduce their errors. We exposed hemiparetic stroke survivors and healthy age-matched controls to a pattern of disturbing forces that have been found by previous studies to induce a dramatic adaptation in healthy individuals. Eighteen stroke survivors made 834 movements in the presence of a robot-generated force field that pushed their hands proportional to its speed and perpendicular to its direction of motion - either clockwise or counterclockwise. We found that subjects could adapt, as evidenced by significant after-effects. After-effects were not correlated with the clinical scores that we used for measuring motor impairment. Further examination revealed that significant improvements occurred only when the training forces magnified the original errors, and not when the training forces reduced the errors or were zero. Within this constrained experimental task we found that error-enhancing therapy (as opposed to guiding the limb closer to the correct path) to be more effective than therapy that assisted the subject.}, address = {Sensory Motor Performance Program, Rehabilitation Institute of Chicago, Physical Medicine \& Rehabilitation, Mechanical and Biomedical Engineering, Northwestern University, 345 East Superior St., Room 1406, Chicago, IL, 60611, USA, j-patton@northwestern.edu.}, author = {Patton, James L. and Stoykov, Mary E. and Kovic, Mark and Mussa-Ivaldi, Ferdinando A. }, citeulike-article-id = {552889}, doi = {http://dx.doi.org/10.1007/s00221-005-0097-8}, issn = {0014-4819}, journal = {Exp Brain Res}, keywords = {motorlearning, stroke}, month = {January}, number = {3}, pages = {368--383}, posted-at = {2006-03-15 13:11:50}, priority = {2}, title = {Evaluation of robotic training forces that either enhance or reduce error in chronic hemiparetic stroke survivors.}, url = {http://dx.doi.org/10.1007/s00221-005-0097-8}, volume = {168}, year = {2006} }

TY - JOUR ID - citeulike:552889 L3 - citeulike-article-id:552889 TI - Evaluation of robotic training forces that either enhance or reduce error in chronic hemiparetic stroke survivors. JF - Exp Brain Res VL - 168 IS - 3 SP - 368 EP - 383 AD - Sensory Motor Performance Program, Rehabilitation Institute of Chicago, Physical Medicine & Rehabilitation, Mechanical and Biomedical Engineering, Northwestern University, 345 East Superior St., Room 1406, Chicago, IL, 60611, USA, j-patton@northwestern.edu. SN - 0014-4819 N2 - This investigation is one in a series of studies that address the possibility of stroke rehabilitation using robotic devices to facilitate "adaptive training." Healthy subjects, after training in the presence of systematically applied forces, typically exhibit a predictable "after-effect." A critical question is whether this adaptive characteristic is preserved following stroke so that it might be exploited for restoring function. Another important question is whether subjects benefit more from training forces that enhance their errors than from forces that reduce their errors. We exposed hemiparetic stroke survivors and healthy age-matched controls to a pattern of disturbing forces that have been found by previous studies to induce a dramatic adaptation in healthy individuals. Eighteen stroke survivors made 834 movements in the presence of a robot-generated force field that pushed their hands proportional to its speed and perpendicular to its direction of motion - either clockwise or counterclockwise. We found that subjects could adapt, as evidenced by significant after-effects. After-effects were not correlated with the clinical scores that we used for measuring motor impairment. Further examination revealed that significant improvements occurred only when the training forces magnified the original errors, and not when the training forces reduced the errors or were zero. Within this constrained experimental task we found that error-enhancing therapy (as opposed to guiding the limb closer to the correct path) to be more effective than therapy that assisted the subject. KW - motorlearning KW - stroke AU - Patton, James AU - Stoykov, Mary AU - Kovic, Mark AU - Mussa-Ivaldi, Ferdinando PY - 2006/01// UR - http://dx.doi.org/10.1007/s00221-005-0097-8 ER -