Movement Disorders Unit, Department of Neurology, Tel-Aviv Sourasky Medical Center, Tel-Aviv, Israel.
Gait Posture. 2012 Apr;35(4):641-6. doi: 10.1016/j.gaitpost.2011.12.016. Epub 2012 Feb 18.
Patients with Parkinson's disease (PD) have difficulties performing a dual task (DT) while walking and may use the "posture second" strategy. It is not clear if this is a result of motor or cognitive impairments. We examined the effects of explicit prioritization of walking or the cognitive task on gait speed (GS) and variability in 20 patients (Hoehn & Yahr stage: 2.3 ± 0.5) and 20 healthy older adults during usual-walking and under three DT (verbal-fluency) conditions: (1) no instruction for prioritization, (2) specific attention to the walking pattern (gait prioritization), and (3) specific attention to the cognitive task (prioritization of verbal-fluency). The Montreal Cognitive Assessment, the Frontal Assessment Battery, and the Trail Making Tests assessed cognitive status. The two groups did not differ on these cognitive tests. Compared to usual-walking, all subjects reduced their GS in the un-instructed DT condition. Compared to the un-instructed DT condition, both groups significantly (p < 0.001) increased GS when prioritizing walking and maintained about the same GS when prioritizing the cognitive task (p > 0.155). All three DT conditions increased gait variability in both groups (p < 0.001 usual-walking compared to uninstructed DT). Verbal-fluency tended (p = 0.073) to be influenced by prioritization in both groups. Task prioritization abilities were similar in the patients and controls, even though the patients generally walked more slowly. PD patients without cognitive impairment apparently utilize their cognitive resources in the same manner as healthy older adults. Both groups, however, use some form of the posture second strategy and naturally focus on the cognitive task.
帕金森病（PD）患者在行走时进行双重任务（DT）有困难，可能会使用“姿势第二”策略。目前尚不清楚这是运动还是认知障碍的结果。我们检查了明确优先考虑行走或认知任务对 20 名患者（Hoehn 和 Yahr 分期：2.3±0.5）和 20 名健康老年人在通常行走和三种 DT（言语流畅性）条件下的步态速度（GS）和变异性的影响：（1）无优先级指令，（2）特别注意行走模式（步态优先级），（3）特别注意认知任务（言语流畅性优先级）。蒙特利尔认知评估、额叶评估量表和连线测试评估认知状态。两组在这些认知测试上没有差异。与通常行走相比，所有受试者在无指令 DT 条件下降低了 GS。与无指令 DT 条件相比，两组在优先考虑行走时显着（p<0.001）增加了 GS，而在优先考虑认知任务时保持了大致相同的 GS（p>0.155）。所有三种 DT 条件都增加了两组的步态变异性（p<0.001 与无指令 DT 相比）。言语流畅性在两组中均倾向于（p=0.073）受优先级影响。即使患者的行走速度通常较慢，患者和对照组的任务优先级能力也相似。然而，两组都使用某种形式的姿势第二策略，并自然关注认知任务。
