Does the frequency content of the surface mechanomyographic signal reflect motor unit firing rates? A brief review
Does the frequency content of the surface mechanomyographic signal reflect motor unit firing rates? A brief review
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DOI：
10.1016/j.jelekin.2005.12.002
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发表时间：
2007-02-01
影响因子：
2.5
通讯作者：
Malek, Moh H.
中科院分区：
文献类型：
--
作者：
Beck, Travis W.;Housh, Terry J.;Malek, Moh H.
本综述的目的是回顾研究肌力图 (MMG) 频率与运动单位放电率之间潜在关系的文献。已经使用了几种不同的实验设计/方法来解决这个问题，包括：重复电刺激、具有不同纤维类型组成的肌肉中的随意肌肉动作、疲劳和非疲劳等长或动态肌肉动作，以及年轻受试者与老年受试者以及健康个体与患有神经肌肉疾病的受试者中的随意肌肉动作。一般来说，这些研究的结果表明 MMG 频率与运动单位激活速率和肌纤维的收缩特性（收缩和松弛时间）有关。然而，其他研究报告称，MMG 平均功率频率 (MPF) 并不总是遵循预期的放电率调制模式（例如，运动单位放电率通常在等长肌肉动作期间随着扭矩而增加，但 MMG MPF 可能保持稳定甚至下降）。此外，有几个因素可能会影响随意肌肉动作期间 MMG 信号的频率内容（即肌肉僵硬、肌内流体压力等），与运动单位放电率的变化无关。尽管这些因素存在潜在影响，但大多数证据表明 MMG 信号的频域包含一些有关运动单位放电率的信息。然而，该信息很可能是定性的，而不是定量的，并且反映了整体运动单位的放电率，而不是特定运动单位组的放电率。 (C) 2006 Elsevier Ltd. 保留所有权利。
The purpose of this review is to examine the literature that has investigated the potential relationship between mechanomyographic (MMG) frequency and motor unit firing rates. Several different experimental designs/methodologies have been used to address this issue, including: repetitive electrical stimulation, voluntary muscle actions in muscles with different fiber type compositions, fatiguing and non-fatiguing isometric or dynamic muscle actions, and voluntary muscle actions in young versus elderly subjects and healthy individuals versus subjects with a neuromuscular disease(s). Generally speaking, the results from these investigations have suggested that MMG frequency is related to the rate of motor unit activation and the contractile properties (contraction and relaxation times) of the muscle fibers. Other studies, however, have reported that MMG mean power frequency (MPF) does not always follow the expected pattern of firing rate modulation (e.g. motor unit firing rates generally increase with torque during isometric muscle actions, but MMG MPF may remain stable or even decrease). In addition, there are several factors that may affect the frequency content of the MMG signal during a voluntary muscle action (i.e. muscle stiffness, intramuscular fluid pressure, etc.), independent of changes in motor unit firing rates, Despite the potential influences of these factors, most of the evidence has suggested that the frequency domain of the MMG signal contains some information regarding motor unit firing rates. It is likely, however, that this information is qualitative, rather than quantitative in nature, and reflects the global motor unit firing rate, rather than the firing rates of a particular group of motor units. (C) 2006 Elsevier Ltd. All rights reserved.