Na D L, Adair J C, Williamson D J, Schwartz R L, Haws B, Heilman K M
Department of Neurology, College of Medicine, University of Florida, Gainesville 32610-0236, USA.
J Neurol Neurosurg Psychiatry. 1998 Mar;64(3):331-8. doi: 10.1136/jnnp.64.3.331.
Spatial neglect may result from disruption of sensory-attentional systems that spatially allocate perceptual resources and the motor-intentional systems that direct exploration and action. Previous studies have suggested that the line bisection task is more sensitive to sensory-attentional disorders and the cancellation task to motor-intentional disorders. A new technique was developed that allows the dissociation of sensory-attentional and motor-intentional deficits in both tasks and thereby allows comparison of these tasks.
Ten patients with right hemispheric injury and hemispatial neglect performed line bisection and cancellation tasks while viewing stimuli on closed circuit TV. Direct view of the exploring hand and the target was precluded; the TV monitor guided performance. The direct condition made the direction of hand movement on the table (workspace) congruent with that on the monitor. Inverting the camera produced the indirect condition wherein the lateral movement in the workspace occurred in the opposite direction on the monitor.
On the cancellation task, five patients marked targets in the right workspace in the direct condition but the left workspace in the indirect condition, indicating sensory-attentional neglect. However, four other patients cancelled targets only in the right workspace in both conditions, failing to explore the left workspace, suggesting motor-intentional neglect. A patient who performed ambiguously may have elements of both types of neglect. Only two out of five patients designated as sensory-attentional in cancellation tasks showed sensory neglect on line bisection. The other three patients, as well as patients defined as motor-intentional by cancellation performance, exhibited motor-intentional neglect on line bisection.
The designation of sensory-attentional versus motor-intentional neglect therefore, in part, depends on task specific demands.
空间忽视可能源于感觉 - 注意系统的破坏，该系统在空间上分配感知资源，以及运动 - 意向系统，该系统指导探索和行动。先前的研究表明，直线二等分任务对感觉 - 注意障碍更敏感，而划消任务对运动 - 意向障碍更敏感。开发了一种新技术，该技术可以在两项任务中分离感觉 - 注意和运动 - 意向缺陷，从而可以比较这些任务。
10名患有右半球损伤和半侧空间忽视的患者在闭路电视上观看刺激物时执行直线二等分和划消任务。排除对探索手和目标的直接视野；电视监视器指导操作。直接条件使手在桌子（工作空间）上的移动方向与监视器上的移动方向一致。反转摄像头产生间接条件，其中工作空间中的横向移动在监视器上以相反方向发生。
在划消任务中，5名患者在直接条件下标记了右侧工作空间中的目标，但在间接条件下标记了左侧工作空间中的目标，表明存在感觉 - 注意忽视。然而，其他4名患者在两种条件下都只在右侧工作空间中划消目标，未能探索左侧工作空间，提示存在运动 - 意向忽视。一名表现不明确的患者可能同时具有两种类型忽视的成分。在划消任务中被指定为感觉 - 注意型的5名患者中，只有2名在直线二等分任务中表现出感觉忽视。其他3名患者以及根据划消表现被定义为运动 - 意向型的患者，在直线二等分任务中表现出运动 - 意向忽视。
因此，感觉 - 注意忽视与运动 - 意向忽视的判定部分取决于任务的特定要求。
