Motor Behavior Laboratory, University of Florida, Gainesville, FL, USA.
Motor Behavior Laboratory, University of Florida, Gainesville, FL, USA.
Neurosci Biobehav Rev. 2015 May;52:38-48. doi: 10.1016/j.neubiorev.2015.02.005. Epub 2015 Feb 19.
Force control deficits are common dysfunctions after a stroke. This review concentrates on various force control variables associated with motor impairments and suggests new approaches to quantifying force control production and modulation. Moreover, related neurophysiological mechanisms were addressed to determine variables that affect force control capabilities. Typically, post stroke force control impairments include: (a) decreased force magnitude and asymmetrical forces between hands, (b) higher task error, (c) greater force variability, (d) increased force regularity, and (e) greater time-lag between muscular forces. Recent advances in force control analyses post stroke indicated less bimanual motor synergies and impaired low-force frequency structure. Brain imaging studies demonstrate possible neurophysiological mechanisms underlying force control impairments: (a) decreased activation in motor areas of the ipsilesional hemisphere, (b) increased activation in secondary motor areas between hemispheres, (c) cerebellum involvement, and (d) relatively greater interhemispheric inhibition from the contralesional hemisphere. Consistent with identifying neurophysiological mechanisms, analyzing bimanual motor synergies as well as low-force frequency structure will advance our understanding of post stroke force control.
力控制缺陷是中风后常见的功能障碍。本综述集中讨论了与运动障碍相关的各种力控制变量，并提出了量化力控制产生和调节的新方法。此外，还探讨了相关的神经生理机制，以确定影响力控制能力的变量。通常，中风后力控制障碍包括：（a）力幅度减小，双手之间的力不对称，（b）任务错误增加，（c）力变异性增加，（d）力规律性增加，以及（e）肌肉力之间的时滞增加。最近对中风后力控制分析的进展表明，双手运动协同作用减少，低频力结构受损。脑成像研究表明，力控制障碍的潜在神经生理机制包括：（a）对侧半球运动区的激活减少，（b）半球间次级运动区的激活增加，（c）小脑的参与，以及（d）来自对侧半球的相对较大的抑制。与确定神经生理机制一致，分析双手运动协同作用以及低频力结构将有助于我们更好地理解中风后的力控制。
