Program in Physical Therapy, Washington University School of Medicine, Campus Box 8502, 4444 Forest Park Blvd. St. Louis, MO 63108, USA.
Parkinsonism Relat Disord. 2012 Jun;18(5):462-8. doi: 10.1016/j.parkreldis.2012.01.002. Epub 2012 Jan 20.
Difficulty switching between motor programs is a proposed cause of motor blocks in Parkinson disease (PD). Switching from one movement to another has been studied in the upper extremity and during postural control tasks, but not yet in the eyes and lower limb in PD. The purpose of this study was to compare movement orientation switching ability between people with PD and age-matched controls (CON) and to determine if switching ability is correlated between the eyes and lower limb. Twenty-six persons with PD and 19 age-matched controls participated. Movement orientation switching was studied in a seated position with the head fixed in a chinrest. In response to a randomly generated tone, participants switched from a continuous back-and-forth movement in either the horizontal or vertical orientation to the opposite orientation as quickly as possible. Lower limb movements were performed with the great toe pointing back and forth between targets positioned on a 45° angled floor platform. Eye movements were back and forth between the same targets. Eye and lower limb switch time was reduced in PD (p<0.01), but after normalizing switch time to movement velocity, no differences existed between PD and CON. Eye and lower limb switch times were correlated in PD (r=0.513, p<0.01) but not in CON. In PD, switch time and movement velocity of the lower limb, but not the eyes, correlated with bradykinesia and postural instability/gait. Our results suggest that individuals with PD experience movement-switching deficits with both the eyes and lower limb, perhaps driven by overall bradykinesia.
运动程序之间的切换困难是帕金森病（PD）运动障碍的一个提出的原因。已经在上肢和姿势控制任务中研究了从一种运动到另一种运动的切换，但尚未在 PD 患者的眼睛和下肢中研究。本研究的目的是比较 PD 患者与年龄匹配的对照组（CON）之间的运动方向切换能力，并确定眼睛和下肢之间的切换能力是否相关。共有 26 名 PD 患者和 19 名年龄匹配的对照组参与者参加了本研究。运动方向切换是在头部固定在下巴托上的坐姿下进行的。响应随机生成的音调，参与者尽可能快地从水平或垂直方向的连续前后运动切换到相反的方向。下肢运动是用大脚趾在位于 45°倾斜地板平台上的目标之间来回移动。眼部运动是在相同的目标之间来回进行的。PD 患者的下肢和眼部切换时间减少（p<0.01），但将切换时间归一化为运动速度后，PD 和 CON 之间没有差异。PD 患者的眼部和下肢切换时间相关（r=0.513，p<0.01），但 CON 患者则没有。在 PD 患者中，下肢的切换时间和运动速度，而不是眼睛，与运动迟缓症和姿势不稳定/步态有关。我们的结果表明，PD 患者的眼睛和下肢都存在运动切换缺陷，这可能是由整体运动迟缓症引起的。
