School of Psychology, University College Dublin, Dublin, Ireland.
Centre for Motor Control, Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, Canada.
Sci Rep. 2023 Oct 31;13(1):18749. doi: 10.1038/s41598-023-42705-x.
Action observation and imitation may facilitate movement in Parkinson's disease (PD). People with PD have been found to imitate intransitive actions similarly to neurologically healthy older adults, but their imitation of object-directed hand movements has not previously been investigated using kinematic measures. The present study examined observation and imitation of object-directed hand movements in 18 participants with PD and 21 neurologically healthy age-matched control participants. Participants observed and immediately imitated sequences showing a human hand reaching for and transferring an object between horizontal positions. Both groups significantly modulated their finger movements, showing higher vertical amplitude when imitating elevated compared to direct trajectories. In addition, movements were lower in vertical amplitude and higher in velocity when imitating the reaching segment than the transfer segment. Eye-tracking revealed that controls made smaller saccades when observing predictable than unpredictable elevated movements, but no effects of predictability on eye movements were found for the PD group. This study provides quantitative evidence that people with mild to moderate PD can imitate object-directed hand movement kinematics, although their prediction of such movements may be reduced. These findings suggest that interventions targeting object-directed actions may capitalize on the ability of people with PD to imitate kinematic parameters of a demonstrated movement.
动作观察和模仿可能有助于帕金森病（PD）患者的运动。已经发现，PD 患者的模仿非传递动作与神经健康的老年成年人相似，但他们对指向物体的手部动作的模仿以前没有使用运动学测量进行研究。本研究检查了 18 名 PD 患者和 21 名神经健康年龄匹配的对照组参与者对指向物体的手部运动的观察和模仿。参与者观察并立即模仿了显示人手到达和在水平位置之间转移物体的序列。两组参与者的手指运动都显著调节，模仿升高的轨迹比直接轨迹时垂直幅度更高。此外，在模仿到达段时，运动的垂直幅度较低，速度较高，而在模仿转移段时，垂直幅度较低，速度较高。眼动追踪显示，对照组在观察可预测的升高运动时比不可预测的升高运动时的眼跳幅度更小，但 PD 组的眼动没有表现出可预测性的影响。这项研究提供了定量证据，表明轻度至中度 PD 患者可以模仿指向物体的手部运动运动学，尽管他们对这些运动的预测可能会减少。这些发现表明，针对指向物体的动作的干预措施可能会利用 PD 患者模仿演示运动的运动学参数的能力。
