Kuo Yi-Ling, Dubuc Tobin, Boufadel Danielle F, Fisher Beth E
Division of Biokinesiology and Physical Therapy, University of Southern California, Los Angeles, CA, United States.
Brain Res. 2017 Nov 1;1674:77-83. doi: 10.1016/j.brainres.2017.08.015. Epub 2017 Aug 18.
Ipsilateral silent period (iSP) is a frequently measured index of interhemispheric inhibition. However, the methodology used across studies has been inconsistent and variable. We investigated the optimal contraction level and quantification methods for achieving iSP measurement consistency. Twenty-five healthy adults performed right isometric thumb abduction under three conditions (30%, 50%, and 100% of maximal voluntary contraction) while transcranial magnetic stimulation was applied over the primary motor cortex representational area of the abductor pollicis brevis. iSP was quantified by: iSP duration, iSP area and normalized iSP. Measurement consistency was determined by the homogeneity of variance test and by the coefficient of variation. iSP was consistent across all contraction levels when measured by iSP duration and normalized iSP. Normalized iSP showed the least measurement variability. We propose that future investigations examining interhemispheric inhibition use normalized iSP for measurement consistency and the ability to compare results across studies.
同侧静息期（iSP）是半球间抑制的一个常用测量指标。然而，各研究中使用的方法并不一致且存在差异。我们研究了实现iSP测量一致性的最佳收缩水平和量化方法。25名健康成年人在三种条件下（最大自主收缩的30%、50%和100%）进行右侧等长拇指外展，同时在拇短展肌的初级运动皮层代表区施加经颅磁刺激。iSP通过以下方式进行量化：iSP持续时间、iSP面积和标准化iSP。测量一致性通过方差齐性检验和变异系数来确定。当通过iSP持续时间和标准化iSP进行测量时，iSP在所有收缩水平上都是一致的。标准化iSP的测量变异性最小。我们建议，未来研究半球间抑制时，使用标准化iSP以确保测量一致性，并便于跨研究比较结果。
