Neural substrates for motor imagery in severe hemiparesis
Neural substrates for motor imagery in severe hemiparesis
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DOI：
10.1177/1545968306286958
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发表时间：
2006-06-01
影响因子：
4.2
通讯作者：
Walker, SR
中科院分区：
文献类型：
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作者：
Kimberley, TJ;Khandekar, G;Walker, SR
背景资料。想象的运动对运动学习和表现的有益影响表明，运动想象在功能上接近于准备和执行运动的过程。目标。这项研究的目的是研究与严重偏瘫受试者手腕运动想象相关的皮质突起。方法：研究方法。在功能磁共振成像期间，中风受试者用偏瘫的手进行想象的手腕跟踪运动，用未受影响的手进行主动手腕跟踪运动，以及休息。控制受试者使用指定的手执行相同的任务。通过激活体素和信号强度的偏侧性指数确定初级运动(MI)、初级感觉(SI)、辅助运动区(SMA)和SMA前区域的皮质激活。想象能力用表象评定量表进行评定。结果。在赛道条件下，所有受试者主要表现为对侧控制。在想象状态下，健康受试者在所有区域都表现出对侧控制，而中风受试者在SI中主要表现为对侧激活，而在MI和SMA中主要表现为同侧激活。在想象状态下，中风受试者的同侧大脑半球信号强度的百分比变化大于健康受试者的同侧大脑半球。此外，自我报告的低想象能力的受试者与高想象能力的受试者相比，在激活方面没有差异。结论。这些发现与其他主要证明功能性运动受试者偏瘫手的同侧控制的工作是一致的，并为进一步研究心理意象影响中风恢复者功能相关皮质控制的能力奠定了基础。
Background. The beneficial effects of imagined movements on motor learning and performance suggest that motor imagery is functionally close to preparatory and executive motor processes. Objective. The purpose of this study was to examine the cortical processes associated with imagery of movement of the wrist in subjects with severe hemiparesis. Methods. 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 (MI), primary sensory (SI), 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. Results. 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 SI but ipsilateral in MI 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. Conclusions. 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.