Jeannerod M, Decety J, Michel F
Vision et Motricité, U.94 de l'I.N.S.E.R.M., Bron, France.
Neuropsychologia. 1994 Apr;32(4):369-80. doi: 10.1016/0028-3932(94)90084-1.
The observation of a patient (A.T.) with a bilateral posterior parietal lesion of vascular origin is reported. A.T. presented a bilateral (more marked on the right) deficit in grasping simple objects (neutral cylindrical dowels) without deficit in reaching toward the location of these objects. The major symptom was an exaggerated anticipatory opening of the fingers with poor correlation with object size, resulting in awkward grasps. It was present both when the hand was visible to the subject and when it was not. This deficit was much less marked if the neutral objects were replaced by usual objects of the same sizes. Finally, in tasks where she had to indicate with her fingers the size of visual objects presented as virtual images through a mirror, or the size of imagined usual objects, A.T. performed normally. These results are discussed within the framework of a dual representation of objects. Only the "pragmatic" representation for steering object-oriented actions would be impaired in this patient as a result of posterior parietal damage. By contrast the semantic representation for object identification would be intact.
报告了对一名患有血管源性双侧顶叶后部病变患者（A.T.）的观察情况。A.T.在抓取简单物体（中性圆柱形棒）时存在双侧（右侧更明显）缺陷，但在伸手够向这些物体的位置时没有缺陷。主要症状是手指过度的预期性张开，与物体大小的相关性较差，导致抓握动作笨拙。当手对受试者可见和不可见时均存在此症状。如果将中性物体换成相同大小的常用物体，这种缺陷就会明显减轻。最后，在她必须用手指指出通过镜子呈现为虚拟图像的视觉物体大小，或想象中的常用物体大小的任务中，A.T.表现正常。这些结果在物体双重表征的框架内进行了讨论。由于顶叶后部受损，该患者仅在引导面向物体的动作时的“实用”表征会受到损害。相比之下，用于物体识别的语义表征将是完整的。
