Improving Grip Control Using a Dynamic Speed-Accuracy Tradeoff Protocol

Nam H. Kim1, Steven Escaldi2 , Adam Shain1 , Michael Wininger1, and William Craelius1
 1 Department of Biomedical Engineering, Rutgers, The State University of New Jersey
Piscataway, NJ  
2 JFK Johnson Institute for Rehabilitation, Edison, NJ

ABSTRACT

Restoring fine motor control in persons with chronic hemiparesis remains a challenge for rehabilitation engineers.  The present study introduces an ergonomic grip force detection device, Gripper, for the biofeedback-based motor rehabilitation of hemiparesis in chronic stroke patients.  Using the Gripper, we were able to validate Fitts’ speed-accuracy tradeoff (SAT) in dynamic grasping tasks in non-neurologically impaired persons, and assess the restoration of motor function in a cohort of chronic stroke patients over time according to their SAT parameters.  A pilot study with eight healthy subjects revealed that the speed of force production and its accuracy to match a force target are log-linearly related.  Four chronic stroke patients exhibited significant improvements in their adherence to a Fitts’-like relationship following a 6-week training programme with the Gripper.

KEYWORDS

Stroke, grip, grasp, motor control,  biofeedback.

ACKNOWLEDGMENTS

This study was funded by the National Institute on Disability and Rehabilitation Research (NIDRR) SBIR grant to Nian-Crae Inc., Somerset, NJ.  Technical assistance was provided by Carey Glass, CPO.

Author Contact Information:

Nam H. Kim, PhD, Rutgers University, 599 Taylor Road, Piscataway, NJ 08854, Office Phone (732) 445-1178  EMAIL: namhkim@msn.com