The Department of Neurosurgery (van Wouwe, Wylie) and the Department of Neurology (Mohanty, Lingaiah, LaFaver), University of Louisville, Louisville, Ky.; and the Department of Neurology, Vanderbilt University Medical Center, Nashville (van Wouwe).
J Neuropsychiatry Clin Neurosci. 2020 Winter;32(1):73-78. doi: 10.1176/appi.neuropsych.19030076. Epub 2019 Oct 7.
Despite being a major cause of neurological disability, the neural mechanisms of functional movement disorders (FMDs) remain poorly understood. Recent studies suggest that FMD is linked to dysfunctional motor and prefrontal regions that could lead to motor and cognitive impairments. The aim of this study was to investigate different components of action control in FMD by using choice-reaction, stop-signal, and Simon tasks.
Thirty patients with an FMD were prospectively recruited from the University of Louisville Movement Disorders Clinic and compared with 53 healthy control subjects, recruited from the Vanderbilt University Medical Center Movement Disorders Clinic. FMD motor symptom severity was rated with the Simplified Functional Movement Disorder Rating Scale (S-FMDRS). By using a computer and handheld response grips, participants completed three action-control tasks (choice-reaction task, stop-signal task, and Simon task) that tested action initiation, action cancelation, and interference control over actions. Action-control measures were compared between groups with analyses of variance.
Patients with FMD were less proficient in suppressing incorrect response impulses on the Simon task and were slower to stop on the stop-signal task compared with healthy control subjects. No significant correlation with neuropsychological measurements, S-FMDRS scores, and action-control measurements was observed.
These results suggest that two forms of inhibitory control, selective impulse inhibition and global action cancelation, are impaired in patients with FMD, independent of slowing on go reaction times. Improved understanding of action control in FMD may help in the development of new diagnostic and therapeutic strategies.
尽管功能运动障碍（FMD）是导致神经功能障碍的主要原因之一，但对其神经机制仍了解甚少。最近的研究表明，FMD 与功能失调的运动和前额叶区域有关，这可能导致运动和认知障碍。本研究旨在通过使用选择反应、停止信号和 Simon 任务来研究 FMD 中不同的动作控制成分。
前瞻性地从路易斯维尔大学运动障碍诊所招募了 30 名 FMD 患者，并与来自范德比尔特大学医学中心运动障碍诊所的 53 名健康对照者进行比较。使用简化功能性运动障碍评定量表（S-FMDRS）对 FMD 运动症状的严重程度进行评定。通过使用计算机和手持响应夹具，参与者完成了三个动作控制任务（选择反应任务、停止信号任务和 Simon 任务），测试了动作启动、动作取消和对动作的干扰控制。通过方差分析比较了两组的动作控制测量值。
与健康对照组相比，FMD 患者在 Simon 任务中抑制错误反应冲动的能力较差，在停止信号任务中停止的速度较慢。未观察到与神经心理学测量、S-FMDRS 评分和动作控制测量值之间存在显著相关性。
这些结果表明，两种形式的抑制控制，选择性冲动抑制和整体动作取消，在 FMD 患者中受损，与 Go 反应时的减慢无关。对 FMD 中动作控制的深入了解可能有助于开发新的诊断和治疗策略。
