从语音工作记忆视角解析特殊言语损伤

Genetic Influences on Specific Language Impairment and Phonological Working Memory

本文首先简介了语音工作记忆(pWM)的本质及其与特殊语言损伤(SLI)的关系,指出pWM是用来对SLI表现型进行量化的一种认知指标,pWM任务中得分越低,表明存在SLI的可能性越大,然后从pWM角度阐述了SLI的心理机制模型,即自上而下简单模型和危险因素理论模型,以及SLI的相关遗传学研究,最后,指出SLI的产生是pWM缺陷和其他因素共同作用产生的,pWM得分低也只是作为遗传表现型的一个显著标志之一。迄今为止人们对表现型的理解,是不可能在认知缺陷和基因型之间建立一一对应的关系,未来有关SLI及其他发展性言语障碍的病因学理论,是需要遗传学者和心理学家共同努力来完成的。

Specific language impairment （SLI） is a developmental language disorder in the absence of frank neurological, sensori-motor, non-verbal cognitive or social emotional deficits under the natural language environment. The paper firstly introduces phonological working memory and explaines SLI from the view of phonological working memory （ A simple bottom-up model and A risk-factor model ）. The former was put forward by Baddeley et al. which proposed that weak phonological working memory （WM） led to SLI by retarding vocabulary learning and acquisition of grammar. The risk-factor model was the aetiology of SLI rather than being different manifes- tations of the same underlying disorder, auditory, phonological and morphosyntactic deficits had distinct causes, and each deficit increased the probability that clinically significant SLI would result. Deficient phonological WM had been linked to specific geneticloci, and might play a role in determining some types of reading impairment as well as SLI. Identifying those cognitive deficits that Work best as indices of heritable phenotypes would help us to uncover the aetiology of developmental disorders. There are still some questions remained to us to the futher study. For example, are there common mechanisms underlying SLI and dyslexia？ What is the gene on chromosome 16 and what biological processes is it involved in？ And will we find different linkages if the phenotype is defined in terms of syntactic deficits, etc.