Reed C L, Caselli R J, Farah M J
Department of Psychology, University of Denver, CO 80208, USA.
Brain. 1996 Jun;119 ( Pt 3):875-88. doi: 10.1093/brain/119.3.875.
In a series of experimental investigations of a subject with a unilateral impairment of tactile object recognition without impaired tactile sensation, several issues were addressed. First, is tactile agnosia secondary to a general impairment of spatial cognition? On tests of spatial ability, including those directed at the same spatial integration process assumed to be taxed by tactile object recognition, the subject performed well, implying a more specific impairment of high level, modality specific tactile perception. Secondly, within the realm of high level tactile perception, is there a distinction between the ability to derive shape ('what') and spatial ('where') information? Our testing showed an impairment confined to shape perception. Thirdly, what aspects of shape perception are impaired in tactile agnosia? Our results indicate that despite accurate encoding of metric length and normal manual exploration strategies, the ability tactually to perceive objects with the impaired hand, deteriorated as the complexity of shape increased. In addition, asymmetrical performance was not found for other body surfaces (e.g. her feet). Our results suggest that tactile shape perception can be disrupted independent of general spatial ability, tactile spatial ability, manual shape exploration, or even the precise perception of metric length in the tactile modality.
在一系列针对一名触觉物体识别单侧受损但触觉感觉未受损的受试者的实验研究中，探讨了几个问题。首先，触觉失认症是否继发于空间认知的普遍受损？在空间能力测试中，包括那些针对被认为在触觉物体识别中会受到考验的相同空间整合过程的测试，该受试者表现良好，这意味着高级的、特定感觉模态的触觉感知存在更具体的损伤。其次，在高级触觉感知领域，从形状（“什么”）和空间（“哪里”）信息中获取信息的能力之间是否存在区别？我们的测试显示损伤仅限于形状感知。第三，触觉失认症中形状感知的哪些方面受损？我们的结果表明，尽管对度量长度进行了准确编码且手动探索策略正常，但患侧手触觉感知物体的能力随着形状复杂性的增加而下降。此外，在身体的其他表面（如她的脚）未发现不对称表现。我们的结果表明，触觉形状感知可能会独立于一般空间能力、触觉空间能力、手动形状探索，甚至触觉模态中度量长度的精确感知而受到干扰。
