Department of Physical Therapy, Steinhardt School of Culture Education and Human Development, New York University, New York, NY, USA.
Department of Physical Therapy, University of Haifa, Haifa, Israel.
J Vestib Res. 2021;31(6):505-517. doi: 10.3233/VES-201552.
People with PPPD report imbalance, increase in symptoms and impaired function within complex visual environments, but understanding of the mechanism for these behaviors is still lacking.
To investigate postural control in PPPD we compared changes in center of pressure (COP) and head kinematics of people with PPPD (N = 22) and healthy controls (N = 20) in response to different combinations of visual and cognitive perturbations during a challenging balance task.
Participants stood in a tandem position. Static or moving stars (0.2 Hz, 5 mm or 32 mm amplitude, anterior-posterior direction) were displayed through a head-mounted display (HTC Vive). On half the trials, participants performed a serial-3 subtraction task. We measured medio-lateral and anterior-posterior path and acceleration of COP and head.
Controls significantly increased all COP and head parameters with the cognitive task whereas PPPD increased only COP ML path and acceleration. Only controls significantly increased head anterior-posterior & medio-lateral acceleration with moving visual load. Cognitive task performance was similar between groups.
We observed altered postural strategies in people with PPPD, in the form of reduced movement with challenge, particularly around the head segment. The potential of this simple and portable head-mounted display setup for differential diagnosis of vestibular disorders should be further explored.
PPP 患者报告在复杂视觉环境中出现平衡失调、症状加重和功能受损，但对这些行为的机制仍了解甚少。
为了研究 PPPD 的姿势控制，我们比较了 PPPD 患者（N=22）和健康对照组（N=20）在挑战性平衡任务中对不同视觉和认知干扰组合的反应中，压力中心（COP）和头部运动学的变化。
参与者以并脚姿势站立。通过头戴式显示器（HTC Vive）显示静态或移动的星点（0.2Hz，5mm 或 32mm 振幅，前后方向）。在一半的试验中，参与者执行连续 3 减 1 减法任务。我们测量了 COP 和头部的前后向和侧向路径以及加速度。
对照组在认知任务中显著增加了所有 COP 和头部参数，而 PPPD 仅增加了 COP 侧向路径和加速度。只有对照组在移动视觉负荷下显著增加了头部前后向和侧向加速度。认知任务表现两组相似。
我们观察到 PPPD 患者的姿势策略发生了改变，表现为在受到挑战时头部运动减少。这种简单便携的头戴式显示器设置用于前庭障碍的鉴别诊断的潜力应进一步探索。
