布洛卡氏失语症患者句子理解障碍的理论阐释

The Theoretical Explanation of the Sentence Comprehension Disorders of Broca's Aphasics

布洛卡氏失语症患者的句子理解障碍是20世纪70年代末以来神经语言学研究的一个热点问题,研究者提出了各种理论假设来解释患者理解障碍产生的原因,但是它们都存在着明显的局限性。以句法学为基础的理论可以准确地确定患者的障碍,但是只能解释一部分现象;虽然从语言处理角度所提出的各种理论解释力较强,但是比较笼统和模糊,我们无法据此对患者的句子理解障碍作出准确的判断。我们认为,目前各种理论之间并不存在根本性的冲突,它们都从不同的角度和层次对失语症患者的句子理解障碍进行了阐释。从根本上来讲,句子理解的障碍来源于患者认知资源的问题,句子理解过程的具体问题是由认知处理障碍的严重程度差异所造成的。因此,本文在全面梳理各种理论的基础上,从句子理解的过程及其所需认知资源的角度,尝试提出一个综合性的理论阐释框架,以期对布洛卡氏失语症患者的句子理解障碍作出更为全面、更加合理的理论解释。

Sentence comprehension disorders of Broca's aphasics have been a major focus of neurolinguistic research since 1970 s. Theoretical hypotheses have been brought up to explain the causes based on both syntactic theories and language processing models, but there still remain obvious limitations. Theories based on syntax help to accurately ascertain the types of disorders, yet only some of them can be accounted for. Theories in view of speech processing have better explanatory power, but they are relatively general and vague, so it is difficult to precisely describe patients' impaired comprehension. The author believes that there exist no basic disagreements among the different theories, since they account for the sentence comprehension disorders of Broca's aphasics at different levels from different perspectives. It is therefore possible to build a general theoretical framework, in which aphasics' problem with cognitive resources is believed to be the underlying cause and the specific impairments in different stages of sentence comprehension as the results of different degrees of severity of cognitive processing. As a result, on the basis of a critical review about the previous theories, the present paper puts forward a tentative theoretical framework from the perspectives of both sentence comprehension process and its required cognitive resources, which may lead to a more comprehensive and reasonable explanation of the sentence comprehension disorders of Broca's aphasics and also needs further empirical confirmation.