Slaboda J C, Barton J E, Maitin I B, Keshner E A
Dept of Physical Therapy, College of Health Profession, Temple University, Philadelphia, PA 19140, USA.
Annu Int Conf IEEE Eng Med Biol Soc. 2009;2009:1147-50. doi: 10.1109/IEMBS.2009.5333916.
To compare the occurrence of visual field independence/dependence in healthy subjects with patients who are post-stroke using the Rod and Frame Test, and determine whether increased visual dependence is reflected in their postural responses when immersed in a moving visual environment. Eight older and twelve young adults, and twelve patients with cortical or sub-cortical stroke, were asked to align a rod enclosed in a tilted frame to vertical and horizontal. Angular deviations of rod position were calculated and compared. Center-of-mass (COM) of the body was calculated for two patients and two young adults standing in the dark and in an immersive virtual environment to examine their postural responses. Balance of the patients did not appear different from healthy subjects when standing in the dark suggesting they were not dependent on the presence of vision, but more rapid and larger COM displacements emerged in the patients when immersed in a moving visual scene. Patients also exhibited greater errors when aligning the rod compared to both healthy groups. Thus, patients with stroke may be more dependent on visual inputs when they are present, and have more difficulty resolving conflict between the visual and somatosensory cues compared to healthy young or older subjects. This impaired conflict resolution may underlie the rapid instability observed in patients when they were placed in a moving visual environment.
使用杆框测试比较健康受试者与中风后患者视野独立/依赖的发生率，并确定当沉浸在动态视觉环境中时，视觉依赖增加是否反映在他们的姿势反应中。招募了8名老年人和12名年轻人，以及12名皮质或皮质下中风患者，要求他们将倾斜框架内的杆调整到垂直和水平方向。计算并比较杆位置的角度偏差。计算了两名患者和两名年轻人在黑暗中和沉浸式虚拟环境中站立时身体的质心（COM），以检查他们的姿势反应。在黑暗中站立时，患者的平衡与健康受试者似乎没有差异，这表明他们不依赖视觉，但当沉浸在动态视觉场景中时，患者出现了更快、更大的质心位移。与两个健康组相比，患者在调整杆时也表现出更大的误差。因此，中风患者在有视觉输入时可能更依赖视觉，并且与健康的年轻人或老年人相比，在解决视觉和体感线索之间的冲突方面有更多困难。这种冲突解决能力受损可能是患者在置于动态视觉环境中时观察到的快速不稳定的原因。
