Utilizing Interlimb Coupling with Mirrored Deficit Fields for Enhanced Bilateral Arm Movement

This study investigates mirrored deficit fields' effects on bimanual coordination in post-stroke rehabilitation using the NREH-Bimanual robotic platform. We tested our approach with eleven participants (six stroke, five able-bodied), deriving force field parameters from the affected/non-dominant arm's velocity distribution and mirroring them to the unaffected/dominant arm. Movement quality was assessed using Randomness Score, Cumulative Traveling Distance, and Workspace Area across four conditions: null field, unilateral deficit field on affected side, unilateral mirrored deficit field on unaffected side, and bilateral deficit fields. Results showed increased movement quality with deficit field application, particularly when applied bilaterally or to the unaffected arm. The stroke group's affected side improved in Randomness Score $(17-24 \%)$ and workspace area ($16-29 \%$), with enhanced movement perception and speed ($\sim 20 \%$) when deficit fields were applied to the unaffected side. These findings demonstrate mirrored deficit fields' potential as a novel rehabilitation strategy for improving bimanual coordination in stroke patients through interlimb coupling mechanisms.