Kimberley Teresa J, Khandekar Gauri, Skraba Laura L, Spencer Jessica A, Van Gorp Emily A, Walker Sarah R
Program in Physical Therapy, University of Minnesota, Minneapolis, MN 55455, USA.
Neurorehabil Neural Repair. 2006 Jun;20(2):268-77. doi: 10.1177/1545968306286958.
The beneficial effects of imagined movements on motor learning and performance suggest that motor imagery is functionally close to preparatory and executive motor processes.
The purpose of this study was to examine the cortical processes associated with imagery of movement of the wrist in subjects with severe hemiparesis.
During fMRI, subjects with stroke performed alternating blocks of imagining wrist-tracking movements with the hemiparetic hand, active wrist-tracking movements with the unaffected hand, and resting. Control subjects performed the same tasks using an assigned hand. Cortical activation in the primary motor (M1), primary sensory (S1), supplementary motor area (SMA), and pre-SMA regions was determined through a laterality index of active voxels and signal intensity. Ability to imagine was assessed with an Imagery Rating Scale.
All subjects displayed primarily contralateral control during the track condition. Healthy subjects demonstrated contralateral control in all areas during the imagine condition, whereas subjects with stroke displayed primarily contralateral activation in S1 but ipsilateral in M1 and SMA. The percentage change in signal intensity was greater in the ipsilateral hemisphere in subjects with stroke than in the ipsilateral hemisphere in healthy subjects during the imagine condition. Additionally, subjects with self-reported low ability to imagine displayed no difference in activation compared to those with high imagery ability.
These findings are consistent with other works demonstrating primarily ipsilateral control of the hemiparetic hand in subjects with functional movement and lay the groundwork for further investigation into the ability of mental imagery to affect functionally relevant cortical control in subjects recovering from stroke.
想象运动对运动学习和表现具有有益影响，这表明运动想象在功能上与准备性和执行性运动过程密切相关。
本研究旨在检查重度偏瘫患者手腕运动想象相关的皮质过程。
在功能磁共振成像（fMRI）期间，中风患者用偏瘫手交替进行想象手腕追踪运动、用未受影响的手进行主动手腕追踪运动以及休息的组块。对照受试者使用指定的手执行相同任务。通过活跃体素的偏侧性指数和信号强度确定初级运动区（M1）、初级感觉区（S1）、辅助运动区（SMA）和前辅助运动区的皮质激活情况。用想象评定量表评估想象能力。
在追踪状态下，所有受试者主要表现为对侧控制。健康受试者在所有区域均表现出对侧控制，而中风患者在S1主要表现为对侧激活，但在M1和SMA表现为同侧激活。在想象状态下，中风患者同侧半球的信号强度变化百分比高于健康受试者同侧半球。此外，自我报告想象能力低的受试者与想象能力高的受试者相比，激活情况无差异。
这些发现与其他研究结果一致，这些研究表明功能运动的患者中偏瘫手主要受同侧控制，为进一步研究心理意象影响中风康复患者功能相关皮质控制的能力奠定了基础。
