Shaikh Aasef G, Wong Aaron, Zee David S, Jinnah H A
Department of Neurology, Emory University, Atlanta, GA, USA; Center for Neurological Restoration, Cleveland Clinic, Cleveland, OH, USA.
Department of Neurology, The Johns Hopkins University, Baltimore, MD, USA.
Parkinsonism Relat Disord. 2015 Jun;21(6):561-6. doi: 10.1016/j.parkreldis.2015.03.005. Epub 2015 Mar 14.
Rapid head movements associated with a change in fixation (head saccades) have been reported to be slow in cervical dystonia (CD). Such slowing is typically measured as an increase in time to complete a movement. The mechanisms responsible for this slowing are poorly understood.
We measured head saccades in 11 CD patients and 11 healthy subjects using a magnetic search coil technique.
Head saccades in CD took longer to reach a desired target location. This longer duration was due to multiple pauses in the trajectory of the head movement. The head velocity of each segment of the (interrupted) head movement was appropriate for the desired total movement amplitude. The head velocity was, however, higher for the amplitude of the individual interrupted movements. These results suggest that brain programs the proper head movement amplitude, but the movement is interrupted by pathological pauses.
Voluntary head saccades have a longer duration in CD due to frequent pauses. The frequent pauses reflect pathological interruptions of normally programmed intended head movement.
据报道，与注视变化相关的快速头部运动（头部扫视）在颈部肌张力障碍（CD）中较为缓慢。这种减慢通常以完成运动的时间增加来衡量。导致这种减慢的机制尚不清楚。
我们使用磁搜索线圈技术测量了11名CD患者和11名健康受试者的头部扫视。
CD患者的头部扫视到达期望目标位置所需时间更长。这种较长的持续时间是由于头部运动轨迹中的多次停顿。（中断的）头部运动各段的头部速度与期望的总运动幅度相适应。然而，对于单个中断运动的幅度，头部速度更高。这些结果表明，大脑设定了适当的头部运动幅度，但运动被病理性停顿打断。
由于频繁停顿，CD患者的自主头部扫视持续时间更长。频繁停顿反映了正常编程的预期头部运动的病理性中断。
