Lange Florian, Seer Caroline, Salchow Carolin, Dengler Reinhard, Dressler Dirk, Kopp Bruno
Department of Neurology, Hannover Medical School, Hannover, Germany.
Department of Neurology, Hannover Medical School, Hannover, Germany.
Cortex. 2016 Sep;82:133-146. doi: 10.1016/j.cortex.2016.05.018. Epub 2016 Jun 8.
Impaired motor control in primary dystonia has been linked to cortico-basal ganglia alterations that may also give rise to changes in executive functioning. However, no conclusive evidence for executive dysfunction in patients with primary dystonia has been reported yet. We conducted a meta-analysis of the relationship between primary dystonia and performance on the Wisconsin Card Sorting Test (WCST), an established test of executive functioning. Its results revealed a significant effect of medium size, indicating that primary dystonia is associated with moderate performance deficits on the WCST. Building on this finding, we conducted an event-related potential (ERP) study to elucidate the cognitive and neural mechanisms underlying executive dysfunction in primary dystonia. Eighteen patients with blepharospasm, a common form of primary focal dystonia, and 34 healthy matched controls completed a computerized version of the WCST. We specifically compared indicators of two distinct components of executive functioning: set shifting and rule inference. On a behavioral level, blepharospasm patients seemed to have particular difficulty integrating information to infer the correct task rule. In addition, P3a amplitude (as an electrophysiological marker of rule-inference processes) was selectively attenuated in blepharospasm patients. Executive dysfunction in blepharospasm can thus rather be attributed to a rule-inference deficit, whereas set-shifting abilities appear to be relatively unaffected by the disease. Moreover, P3a amplitude attenuation was related to disease duration, indicating that this ERP might serve as a neural indicator of disease progression and executive dysfunction in primary dystonia. These results demonstrate for the first time that pathophysiological alterations in primary dystonia might affect cortical activation for executive functioning.
原发性肌张力障碍中运动控制受损与皮质 - 基底神经节改变有关，这种改变也可能导致执行功能的变化。然而，尚未有关于原发性肌张力障碍患者存在执行功能障碍的确凿证据报道。我们对原发性肌张力障碍与威斯康星卡片分类测验（WCST，一种公认的执行功能测试）表现之间的关系进行了荟萃分析。其结果显示出中等程度的显著效应，表明原发性肌张力障碍与WCST上的中度表现缺陷相关。基于这一发现，我们进行了一项事件相关电位（ERP）研究，以阐明原发性肌张力障碍中执行功能障碍背后的认知和神经机制。18名患有眼睑痉挛（原发性局灶性肌张力障碍的一种常见形式）的患者和34名健康匹配对照完成了WCST的计算机化版本。我们特别比较了执行功能两个不同成分的指标：定势转换和规则推理。在行为层面，眼睑痉挛患者似乎在整合信息以推断正确任务规则方面特别困难。此外，眼睑痉挛患者的P3a波幅（作为规则推理过程的电生理标志物）选择性降低。因此，眼睑痉挛中的执行功能障碍更可归因于规则推理缺陷，而定势转换能力似乎相对不受该疾病影响。此外，P3a波幅降低与疾病持续时间相关，表明该ERP可能作为原发性肌张力障碍疾病进展和执行功能障碍的神经指标。这些结果首次证明原发性肌张力障碍中的病理生理改变可能影响执行功能的皮质激活。
