Chatterjee A
Department of Neurology, University of Alabama at Birmingham.
J Neurol Neurosurg Psychiatry. 1994 Oct;57(10):1236-40. doi: 10.1136/jnnp.57.10.1236.
Vision theorists postulate that knowledge of objects in space is shaped by different spatial coordinate systems. An object may be represented by its location in relation to the viewer, or it may be represented by its own intrinsic spatial properties. When patients with left sided neglect fail to respond to stimuli on the left, it is not clear whether "left" refers to a viewer or an object centred reference frame. To uncouple these two reference frames, eight patients with neglect were asked to centre lines and objects in photographs. Viewer centred neglect would result in images appearing on the right side of photographs and object centred neglect would result in images appearing on the left. Four patients demonstrated viewer centred neglect and three demonstrated object centred neglect. One patient had variable performance, perhaps resulting from competing effects of both viewer and object centred neglect. Stimuli characteristics did not affect the spatial coordinate system in which neglect occurred. These results suggest that viewer centred and object centred reference frames are functionally dissociable, and that patients may have spatial neglect predominantly in either coordinate system.
视觉理论家们推测，空间中物体的认知是由不同的空间坐标系塑造的。一个物体可以通过其相对于观察者的位置来表示，或者通过其自身固有的空间属性来表示。当左侧忽视症患者对左侧的刺激没有反应时，尚不清楚“左侧”是指以观察者为中心还是以物体为中心的参照系。为了区分这两个参照系，研究人员让八名忽视症患者将照片中的线条和物体居中。以观察者为中心的忽视会导致图像出现在照片的右侧，而以物体为中心的忽视会导致图像出现在左侧。四名患者表现出以观察者为中心的忽视，三名患者表现出以物体为中心的忽视。一名患者的表现不稳定，可能是由于以观察者为中心和以物体为中心的忽视的相互竞争作用所致。刺激特征并未影响忽视发生时所采用的空间坐标系。这些结果表明，以观察者为中心和以物体为中心的参照系在功能上是可分离的，并且患者可能主要在这两种坐标系中的一种中存在空间忽视。
