Magnani G, Cursi M, Leocani L, Volonté M A, Locatelli T, Elia A, Comi G
Department of Clinical Neurophysiology, San Raffaele Scientific Institute, University of Milan, Italy.
Mov Disord. 1998 Jul;13(4):653-60. doi: 10.1002/mds.870130408.
The event-related desynchronization (ERD) to voluntary movement is an indicator of cortical activation with a high time resolution and a specific spatial representation. We have evaluated 10 patients affected by Parkinson's disease (PD), free from L-dopa treatment for at least 12 hours, and 10 control subjects. Each subject underwent ERD examination during self-paced movement (SPM) and during contingent negative variation (CNV) paradigms. ERD was measured as the percentage decrease of alpha band power and calculated for frequency bands of 1 Hz, ranging between 8 and 12 Hz. For group comparisons, the frequency showing the highest ERD was selected for each subject and for each side. In the control group, ERD in the CNV paradigm began over the contralateral centroparietal electrodes 1475 ms before movement onset of the right hand and 1375 ms for the left. In the SPM paradigm, ERD started over the contralateral central electrodes 2150 ms and 1775 ms before movement onset of the right and left hand, respectively. In the PD group, ERD started over the contralateral central areas 800 ms and 475 ms before movement onset of the right and left hand, respectively, for CNV paradigm and 1200 ms and 750 ms for the right and left hand, respectively, for SPM paradigm. Therefore, contralateral ERD began closer to movement onset in PD compared with the control group in both paradigms. ERD over the sensorimotor areas ipsilateral to the movement was not significantly different in PD compared with the control group. The finding of delayed contralateral ERD in PD is according to the view that functional cortical activation related to movement preparation is impaired in PD. The lack of group differences in the onset of ipsilateral ERD, which appears close to movement execution than contralateral ERD both in normal subjects and in PD, suggests that different mechanisms may be involved in generating ERD over the hemispheres ipsilateral and contralateral to the movement, and that only the latter are impaired in PD.
与自主运动相关的去同步化（ERD）是一种具有高时间分辨率和特定空间表征的皮质激活指标。我们评估了10例帕金森病（PD）患者，他们至少12小时未接受左旋多巴治疗，以及10名对照受试者。每位受试者在自主节奏运动（SPM）和伴随负变化（CNV）范式期间接受ERD检查。ERD被测量为α波段功率的百分比下降，并针对1Hz的频段进行计算，范围在8至12Hz之间。为了进行组间比较，为每个受试者和每一侧选择显示最高ERD的频率。在对照组中，CNV范式中的ERD在右手运动开始前1475毫秒和左手运动开始前1375毫秒在对侧中央顶叶电极上开始。在SPM范式中，ERD分别在右手和左手运动开始前2150毫秒和1775毫秒在对侧中央电极上开始。在PD组中，对于CNV范式，ERD分别在右手和左手运动开始前800毫秒和475毫秒在对侧中央区域开始，对于SPM范式，分别在右手和左手运动开始前1200毫秒和750毫秒开始。因此，在两种范式中，与对照组相比，PD组的对侧ERD在更接近运动开始时出现。与对照组相比，PD组中与运动同侧的感觉运动区域的ERD没有显著差异。PD组中对侧ERD延迟的发现符合以下观点，即与运动准备相关的功能性皮质激活在PD中受损。在正常受试者和PD患者中，同侧ERD的开始时间缺乏组间差异，同侧ERD似乎比运动对侧的ERD更接近运动执行，这表明在运动同侧和对侧半球产生ERD可能涉及不同的机制，并且只有后者在PD中受损。
