學院

醫學院

系所

職能治療學系

題名

Reactive postural control deficits in patients with posterior parietal cortex lesions following stroke and the effects of auditory cueing

作者

Lin, Y-H., Tang, P-F.*, Wang, Y-H., Eng, J-J., Lin, K-C., Lu, L., Jeng, J-S., & Chen, S-C.

期刊名稱

American Journal of Physical Medicine & Rehabilitation (SCI 期刊)

發表日期

2014

著作性質

原著

語文

英文

關鍵字

Stroke, Posterior Parietal Cortex, Posture, Cues

摘要

Objective: The purpose of this study was to investigate the ways in which stroke-induced posterior parietal cortex (PPC) lesions affect reactive postural responses and whether providing auditory cues modulates these responses.

Design: Seventeen hemiparetic patients following stroke, nine with PPC lesions (PPCLesion) and eight with intact PPCs (PPCSpared), and nine age-matched healthy adults completed a lateral-pull perturbation experiment under non-cued and cued conditions. The activation rates of the gluteus medius muscle ipsilateral (GMi) and contralateral (GMc) to the pull direction, the rates of occurrence of three types of GM activation patterns, and the GMi contraction latency were investigated.

 Results: In non-cued pulls towards the paretic side, of the three groups, the PPCLesion group exhibited the lowest activation rate (56%) of the GMi (P < 0.05), which is the primary postural muscle involved in this task, and the highest rate of occurrence (33%) of the GMc-activation-only pattern (P < 0.05), which is a compensatory activation pattern. In contrast, in cued pulls towards the paretic side, the PPCLesion group were able to increase the activation rate of the GMi to a level (81%) such that there became no significant differences in activation rate of the GMi among the three groups (P > 0.05). However, there were no significant differences in the GM activation patterns and GMi contraction latency between the non-cued and cued conditions for the the PPCLesion group (P > 0.05).

Conclusions: The PPCLesion patients had greater deficits in recruiting paretic muscles and were more likely to use the compensatory muscle activation pattern for postural reactions than the PPCSpared patients, suggesting that PPC is part of the neural circuitry involved in reactive postural control in response to lateral perturbations. The auditory cueing used in this study, however, did not significantly modify the muscle activation patterns in PPCLesion patients. More research is needed to explore the type and structure of cueing that could effectively improve patterns and speed of 26 postural responses in these patients.