摘要：

纯失读症是损害定位于阅读早期阶段即词形加工的功能障碍，症状单一且病变部位特殊，多累及视觉词形加工区域。文字阅读作为一种获得性高级神经功能，与文化密切相关，故比较中西方纯失读症的异同能够更加深入地了解视觉词形加工机制。中西方纯失读症具有不同临床表现，文字信号特征的差异性是根本原因，视觉词形加工区域的可塑性是神经生物学基础。中西方文字阅读均呈现左侧半球偏侧化特点，但汉语纯失读症的特殊现象可推测右侧大脑半球在汉语加工中的作用更为突出。中西方阅读的fMRI 研究均提示视觉词形加工区域内部存在等级结构，对应于亚词汇加工的分级制度，但尚不足以解释汉语纯失读症中词长效应阙如等现象。汉字辨认可能更依赖于腹侧视觉通路即整字的加工。

关键词: 阅读障碍, 单纯性, 中国, 综述

Abstract:

Pure alexia is a dysfunction with simple symptoms and specific impaired regions, which happens at early stage of reading called visual word form processing, and involves visual word form area (VWFA). Reading as an acquired higher nervous function is closely related with culture, so the comparison between Chinese and Western pure alexia could lead to further understanding of visual word form processing mechanism. As the different clinical manifestations of pure alexia in Chinese and Western cultures, the signal distinction of words is the primary cause whereas the plasticity of VWFA is the neurobiological basis. Chinese and Western reading both present left-hemispheric lateralization, but based on the special feature of Chinese pure alexia, it is inferred that the right hemispheric may play a more outstanding role in Chinese word processing. In fMRI research on Chinese and Western reading, it is indicated that there is hierarchical organization in VWFA, which is corresponding to hierarchical coding in sublexical processing, but it cannot elucidate some phenomena in Chinese pure alexia such as absence of word-length effect (WLE). Chinese word recognition might largely rely on ventral visual pathway, i.e. the whole word processing.

Key words: Alexia, pure, China, Review