Polk T A, Reed C L, Keenan J M, Hogarth P, Anderson C A
Department of Psychology, University of Michigan, Ann Arbor, MI 48109, USA.
Brain Cogn. 2001 Dec;47(3):545-63. doi: 10.1006/brcg.2001.1486.
Semantic understanding of numbers and related concepts can be dissociated from rote knowledge of arithmetic facts. However, distinctions among different kinds of semantic representations related to numbers have not been fully explored. Working with numbers and arithmetic requires representing semantic information that is both analogue (e.g., the approximate magnitude of a number) and symbolic (e.g., what / means). In this article, the authors describe a patient (MC) who exhibits a dissociation between tasks that require symbolic number knowledge (e.g., knowledge of arithmetic symbols including numbers, knowledge of concepts related to numbers such as rounding) and tasks that require an analogue magnitude representation (e.g., comparing size or frequency). MC is impaired on a variety of tasks that require symbolic number knowledge, but her ability to represent and process analogue magnitude information is intact. Her deficit in symbolic number knowledge extends to a variety of concepts related to numbers (e.g., decimal points, Roman numerals, what a quartet is) but not to any other semantic categories that we have tested. These findings suggest that symbolic number knowledge is a functionally independent component of the number processing system, that it is category specific, and that it is anatomically and functionally distinct from magnitude representations.
对数字及相关概念的语义理解可以与算术事实的死记硬背相分离。然而，与数字相关的不同种类语义表征之间的区别尚未得到充分探究。运用数字和进行算术运算需要表征既具有模拟性（例如，一个数字的近似大小）又具有符号性（例如，/ 是什么意思）的语义信息。在本文中，作者描述了一位患者（MC），她在需要符号数字知识的任务（例如，包括数字在内的算术符号知识、与数字相关的概念如四舍五入的知识）和需要模拟大小表征的任务（例如，比较大小或频率）之间表现出分离。MC 在各种需要符号数字知识的任务上存在缺陷，但她表征和处理模拟大小信息的能力完好无损。她在符号数字知识方面的缺陷扩展到与数字相关的各种概念（例如，小数点、罗马数字、四重奏是什么），但未扩展到我们所测试的任何其他语义类别。这些发现表明，符号数字知识是数字处理系统中功能上独立的组成部分，它具有类别特异性，并且在解剖学和功能上与大小表征不同。
