Department of Biomedical Signals and Systems, Faculty EEMCS, University of Twente, Postbox 217, 7500 AE, Enschede, The Netherlands.
Department of Neurology, Amsterdam Neuroscience, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands.
J Neuroeng Rehabil. 2020 Mar 17;17(1):45. doi: 10.1186/s12984-020-00670-w.
Parkinson's disease (PD) and essential tremor (ET) are neurodegenerative diseases characterized by movement deficits. Especially in PD, maintaining cyclic movement can be significantly disturbed due to pathological changes in the basal ganglia and the cerebellum. Providing external cues improves timing of these movements in PD and also affects ET. The aim of this study is to determine differences in cortical activation patterns in PD and ET patients during externally and internally cued movements.
Eleven PD patients, twelve ET patients, OFF tremor suppressing medication, and nineteen age-matched healthy controls (HC) were included and asked to perform a bimanual tapping task at two predefined cue frequencies. The auditory cue, a metronome sound presented at 2 or 4 Hz, was alternately switched on and off every 30 s. Tapping at two different frequencies were used since it is expected that different brain networks are involved at different frequencies as has been shown in previous studies. Cortical activity was recorded using a 64-channel EEG cap. To establish the cortical activation pattern in each group, the task related power (TRP) was calculated for each subject. For inter-groups analysis, EEG electrodes for divided into 5 different areas.
Inter-group analysis revealed significant differences in areas responsible for motor planning, organization and regulation and involved in initiation, maintenance, coordination and planning of complex sequences of movements. Within the area of the primary motor cortex the ET group showed a significantly lower TRP than the HC group. In the area responsible for combining somatosensory, auditory and visual information both patient groups had a higher TRP than the HC group.
Different neurological networks are involved during cued and non-cued movements in ET, PD and HC. Distinct cortical activation patterns were revealed using task related power calculations. Different activation patterns were revealed during the 2 and 4 Hz tapping task indicating different strategies to execute movements at these rates. The results suggest that a including a cued/non-cued tapping task during clinical decision making could be a valuable tool in an objective diagnostic protocol.
帕金森病（PD）和特发性震颤（ET）是两种神经退行性疾病，其特征是运动功能障碍。特别是在 PD 中，由于基底神经节和小脑的病理性变化，维持循环运动可能会受到严重干扰。提供外部线索可以改善 PD 患者的运动定时，也会影响 ET。本研究的目的是确定 PD 和 ET 患者在外部和内部线索运动期间皮质激活模式的差异。
纳入 11 名 PD 患者、12 名 ET 患者、停用震颤抑制药物以及 19 名年龄匹配的健康对照者（HC），并要求他们在两个预设线索频率下进行双手敲击任务。听觉线索是每隔 30 秒交替开启和关闭的节拍器声音，频率为 2 或 4 Hz。使用两种不同的频率进行敲击，因为正如先前研究所示，不同的大脑网络可能会在不同的频率下被激活。使用一个 64 通道 EEG 帽记录皮质活动。为了确定每个组的皮质激活模式，为每个受试者计算任务相关功率（TRP）。对于组间分析，将 EEG 电极分为 5 个不同的区域。
组间分析显示，在负责运动规划、组织和调节的区域以及涉及运动起始、维持、协调和复杂序列规划的区域中存在显著差异。在初级运动皮质区域内，ET 组的 TRP 明显低于 HC 组。在负责结合躯体感觉、听觉和视觉信息的区域中，两个患者组的 TRP 均高于 HC 组。
在 ET、PD 和 HC 中，在有线索和无线索运动期间涉及不同的神经网络。使用任务相关功率计算揭示了不同的皮质激活模式。在 2 Hz 和 4 Hz 敲击任务中揭示了不同的激活模式，表明以这些速度执行运动时采用了不同的策略。结果表明，在临床决策中纳入有线索/无线索敲击任务可能是客观诊断方案中的一种有价值的工具。
