Department of Neurology, University of Colorado School of Medicine, Aurora, CO, USA.
Department of Psychiatry, University of Colorado School of Medicine, Aurora, CO, USA.
J Neurosci Res. 2020 Apr;98(4):692-703. doi: 10.1002/jnr.24547. Epub 2019 Nov 6.
Neuroimaging studies using functional magnetic resonance imaging (fMRI), which measures brain activity by detecting the changes in blood oxygenation levels, are advancing our understanding of the pathophysiology of dystonia. Neurobiological disturbances in dystonia, however, may affect neurovascular coupling and impact the interpretability of fMRI studies. We evaluated here whether the hemodynamic response patterns during a behaviorally matched motor task are altered in isolated cervical dystonia (CD). Twenty-five CD patients and 25 healthy controls (HCs) underwent fMRI scanning during a paced finger tapping task (nondystonic task in patients). Imaging data were analyzed using a constrained principal component analysis-a statistical method that combines regression analysis and principal component analysis and enables the extraction of task-related functional networks and determination of the spatial and temporal hemodynamic response patterns associated with the task performance. Data from three patients and two controls were removed due to excessive movement. No significant differences in demographics or motor performance were observed. Three task-associated functional brain networks were identified. During task performance, reduced hemodynamic responses were seen in a sensorimotor network and in a network that included key nodes of the default mode, executive control and visual networks. During rest, reductions in hemodynamic responses were seen in the cognitive/visual network. Lower hemodynamic responses within the primary sensorimotor network in patients were correlated with the increased dystonia severity. Pathophysiological disturbances in isolated CD, such as alterations in inhibitory signaling and dopaminergic neurotransmission, may impact neurovascular coupling. Not accounting for hemodynamic response differences in fMRI studies of dystonia could lead to inaccurate results and interpretations.
使用功能磁共振成像（fMRI）的神经影像学研究通过检测血氧水平变化来测量大脑活动，正在加深我们对肌张力障碍病理生理学的理解。然而，肌张力障碍中的神经生物学紊乱可能会影响神经血管耦联，并影响 fMRI 研究的可解释性。我们在此评估孤立性颈肌张力障碍（CD）患者在行为匹配的运动任务期间的血液动力学反应模式是否发生改变。25 例 CD 患者和 25 名健康对照者（HCs）在进行有节奏的手指敲击任务（患者的非肌张力障碍任务）时接受 fMRI 扫描。使用约束主成分分析（一种将回归分析和主成分分析相结合的统计方法）分析成像数据，该方法可以提取与任务相关的功能网络，并确定与任务表现相关的空间和时间血液动力学反应模式。由于运动过度，有 3 名患者和 2 名对照者的数据被删除。未观察到人口统计学或运动表现的显著差异。确定了三个与任务相关的功能性大脑网络。在任务执行期间，在感觉运动网络和包括默认模式、执行控制和视觉网络关键节点的网络中观察到血液动力学反应减少。在休息期间，在认知/视觉网络中观察到血液动力学反应减少。患者初级感觉运动网络中的血液动力学反应降低与肌张力障碍严重程度增加相关。孤立性 CD 中的病理生理紊乱，如抑制性信号和多巴胺能神经传递的改变，可能会影响神经血管耦联。在肌张力障碍的 fMRI 研究中，如果不考虑血液动力学反应差异，可能会导致不准确的结果和解释。
