Vecera S P, Gilds K S
University of Iowa, Department of Psychology, Iowa City IA 52242, USA.
J Cogn Neurosci. 1998 Sep;10(5):568-80. doi: 10.1162/089892998562979.
Visual agnosia is a neuropsychological syndrome characterized by a failure of object identification. Apperceptive agnosia, an object identification deficit caused by damage to early perceptual processes, has been explained by appealing to both damaged early sensory processes and to damaged preattentive grouping processes. Which of these two explanations best accounts for the behavior of these patients? We present results from two experiments designed to distinguish rival theoretical accounts of apperceptive agnosia. In our studies, we attempted to simulate apperceptive agnosia in neurologically intact subjects. Sensory-deficit accounts of the syndrome predict that degrading visual processing would make normal subjects perform like patients; grouping-deficit accounts predict that removing perceptual organization cues from visual displays would make normal subjects perform like patients. We were able to simulate the behavior of an apperceptive agnosic patient by removing perceptual organization cues, consistent with a grouping-deficit account of this syndrome. The implications for understanding both apperceptive agnosia and normal visual functioning are discussed.
视觉失认症是一种以物体识别障碍为特征的神经心理学综合征。统觉性失认症是由早期感知过程受损导致的物体识别缺陷，对于它的解释既涉及受损的早期感觉过程，也涉及受损的前注意分组过程。这两种解释中哪一种最能说明这些患者的行为呢？我们展示了两个实验的结果，这些实验旨在区分关于统觉性失认症的相互竞争的理论解释。在我们的研究中，我们试图在神经功能正常的受试者中模拟统觉性失认症。该综合征的感觉缺陷解释预测，视觉处理能力的下降会使正常受试者表现得像患者；分组缺陷解释预测，从视觉显示中去除感知组织线索会使正常受试者表现得像患者。我们通过去除感知组织线索能够模拟统觉性失认症患者的行为，这与该综合征的分组缺陷解释一致。本文还讨论了对于理解统觉性失认症和正常视觉功能的意义。
