Abstract
Visually guided bimanual coordination requires precise temporal coupling and accurate scaling of motor output to meet task-specific demands. In Parkinson’s disease (PD), impairments in sensorimotor integration may limit the ability to generate correct force- or movement-based outputs, particularly under multi-frequency coordination constraints. Differences in neural and mechanical control requirements between force-based and movement-based tasks may differentially impact performance in this population. PURPOSE: The purpose of this study was to determine whether individuals with PD can meet the accuracy demands imposed by Lissajous-guided multi-frequency (1:2) bimanual coordination, and to compare temporal and output accuracy between force-based and movement-based task conditions. METHODS: Thirty-one right-handed individuals with Parkinson’s disease completed a bimanual isometric force task and a bimanual movement task. In both tasks, participants produced continuous output with the right hand operating at twice the frequency of the left hand during repeated 20-second trials. In the force condition, participants generated isometric force at a prescribed target level, whereas in the movement condition, participants produced continuous index finger motion. Phase angle velocity (PAV), PAV ratio (PAVR), PAVR error, and output accuracy were computed and analyzed across task, limb, and time bins. RESULTS: The movement condition demonstrated significantly higher PAVR values and lower PAVR error compared to the force condition (p < 0.001), indicating superior temporal coordination accuracy. Significant main effects of Time (bin) were observed for PAVR and PAVR error, with early bins differing from later bins, suggesting performance improves across trials. PAV differed across bins, with limb-dependent effects emerging in later bins for the movement task. Output accuracy was significantly reduced in the force condition relative to the movement condition, with limb differences primarily observed during force-based coordination. CONCLUSION: These findings indicate that task demands strongly influence bimanual coordination performance in Parkinson’s disease. Force-based coordination imposes greater difficulty in meeting Lissajous-guided output accuracy requirements than movement-based coordination, suggesting increased challenges in regulating isometric force during multi-frequency tasks. Characterizing these task-dependent constraints may inform the selection of assessment tools and rehabilitation strategies targeting visuomotor and bimanual control in PD.
Recommended Citation
Luthria, Ananya; Weinrich, Madison M.; and Kennedy, Deanna M.
(2026)
"Comparison of Bimanual Force and Movement Coordination in Parkinson’s Disease,"
International Journal of Exercise Science: Conference Proceedings: Vol. 2:
Iss.
18, Article 93.
Available at:
https://digitalcommons.wku.edu/ijesab/vol2/iss18/93