The role of kinesthesia in motor learning

About one third the stroke survivors of cannot undergo physical therapy due to the inability to move. A novel approach to stroke rehabilitation based on the training of isometric force patterns corresponding to specific dynamic tasks could provide new solutions to offer early rehabilitation therapy to a large population of patients.

To investigate whether one can learn to perform movements by learning the forces required for those movements, we have developed ReFlex, a one-degree-of-freedom wrist robotic device. ReFlex uses a hybrid actuation approach, allowing displaying a wider range of output impedances as well as a safe and efficient means of blocking the output for isometric training and rendering stable resistive force fields.

Currently we’re investigating if healthy subjects can learn a novel wrist dynamic flexion/extension task by simulating the movement, which is calculated from the torque generated at the wrist, and displayed on a monitor as feedback. We compare performance of subjects receiving this isometric training with subjects learning the dynamic wrist task directly.

We hope to develop new safe and low cost passive rehabilitation devices, based on force sensors, which could be made available to a larger public. Further, thanks to its hybrid actuation, ReFlex will allow us to investigate wrist neuromuscular properties.

Figure 1: Healthy subject in the ReFlex.

References

• Chapuis D., Benthem de Grave R., Lambercy O., Gassert R. ReFlex, a Haptic Wrist Interface for Motor Learning and Rehabilitation. In Proc. IEEE Haptics Symposium. 2010; 417-24

Contacts

Dr. Olivier Lambercy
ETH Zurich
Rehabilitation Engineering Lab
LEO B9.2
8092 Zurich
olambercy@ethz.ch

Financial Support

This work is supported by the NCCR Neural Plasticity and Repair, Swiss National Fundation.