【作者】 周路平；

【导师】 姚树桥；

【作者基本信息】 中南大学 ， 应用心理学， 2011， 博士

【摘要】 目的：(1)考察学习障碍儿童在字符连线和图形分类任务中,额叶执行功能的状况；(2)了解学习障碍儿童数字／字符短时记忆和工作记忆的特征；(3)探究学习障碍儿童汉字／数字认知过程的神经机制,以及阅读障碍的核心障碍和数学障碍的认知模块问题。方法：(1)采用精神障碍诊断和统计手册第四版(DSM-Ⅳ-TR)、韦氏智力测验中国修订版(WISC-R)和小学多重成就测验(MATs)等量表,结合教师评定和学生成绩,从467名4～6年级小学生中筛选出22名阅读障碍和21名数学障碍儿童组成实验组,另选21名正常儿童组成对照组,所有参与研究的儿童均获得父母或法定监护人的书面同意。(2)采用连线测验、威斯康星卡片分类测验、短时记忆信息提取实验和汉字／数字识别的事件相关电位技术,对学习障碍儿童和正常儿童的符号认知特征进行考察。结果：(1)字符连线任务中,随着任务难度的提高,学习障碍儿童的反应时明显增加,其中,在干扰量(抗干扰能力)指标上明显不及正常组儿童,二者差异显著(F(2.49)=3.234,p=0.046)。(2)图形分类任务中,学习障碍儿童的正确应答比(F(2.49)=5.018,p=0.010)概念化水平(F(2.49)=3.847,p=0.027)明显不及正常儿童；而错误应答数(F(2.49)=3.674,p=0.031)、非持续性错误比(F(2.49)=3.078,p=0.049)则明显高于正常儿童。(3)与正常儿童相比,随着任务难度增加,数字任务中,学习障碍儿童的正确再认数下降(条件1：F(2.49)=3.63,p<0.05；条件2：F(2.47)=3.79,p<0.05)、反应时增加(条件1：F(=3.93,p<0.05；条件2：F(2.47)=9.04,p<0.05),二者差异显著；字符任务中,学习障碍儿童的正确再认数不及正常组(条件1：F(2.47=3.50,p<0.05；条件2：F(2.47)=4.41,p<0.05),但反应时差异不显著。(4)与正常组儿童相比,学习障碍儿童在汉字或数字符号认知加工中,其枕区P1波幅下降、枕颞区N170/VPP波幅增加、额区LPP波幅偏小,二者差异显著；在早成分及晚成分的潜伏期上,学习障碍组与正常组之间差异均不显著。结论：(1)连线任务和图形分类任务的结果表明,学习障碍儿童在注意、手-眼协调、定势转移、视空间认知等方面明显不及正常儿童,反映出学习障碍儿童的额叶存在执行功能异常或加工水平不足现象；(2)与正常儿童相比,随着任务难度的增加,学习障碍儿童的数字短时记忆/工作记忆水平出现明显下降,但字符记忆的表现并不相同,表明学习障碍儿童的数字及字符记忆方式与正常儿童有着明显不同；(3)不论是汉字认知还是数字认知任务,学习障碍儿童均存在明显的大脑枕叶激活不足、枕颞区异常激活和额叶活动偏低的现象,学习障碍儿童的额叶执行功能低下,既有自身激活不足的问题,也可能受其它脑区存在的功能障碍影响；(4)汉语阅读障碍儿童的认知缺陷主要表现为语音加工障碍,而视觉-阿拉伯数字编码模块的功能异常是汉语数学障碍儿童的主要问题。更多还原

【Abstract】 Purpose:(1)One aim of the study was to investigate the status of frontal executive function in children with learning disabilities by trail making test (TMT) and Wisconsin card sorting test (WCST).(2)The other aim of the study was to analyze the characteristics of short-term memory and working memory in digit and character in children with learning disabilities.(3)The last aim of the study was to understand Chinese characters and digital neural mechanisms of cognitive processes in children with learning disabilities, as well as the core disorder of dyslexia and cognitive obstacles of dyscalculia.Methods:Combined with the teacher evaluation and student achievement scale, the Diagnostic and Statistical Manual of Mental Disorders Fourth Edition (DSM-IV-TR), China’s revised Wechsler intelligence test (WISC-R) and primary multiple achievement tests (MATs) were be adopted. The experimental group had22dyslexics and21dyscalculia were selected from467students in grades4to6, and21normal children were built in control group. All of students were be allowed by their parents or Legal guardian’s written consent, and to study the features of symbol cognitive between learning disabilities and normal children by using trail making test, Wisconsin card sorting test, short-term memory information extraction experiments and Chinese/digital cognition in event-related potential technique. Results:(1)With the difficulty of task was increased, the reaction time of children with learning disability was also increased significantly in TMT. The interference index of children with learning disability was significantly less than the normal group (F(2,49)=3.234,p=0.046).(2)In WCST, the score of children with learning disability was significantly less than the normal group in response of correct ratio(F(2,49)=5.018, p=0.010) and conceptual level(F(2,49;=3.847,p=0.027), and significantly more than the normal group in response of errors(F(2,49)=3.674,p=0.031) and response of non-preservative error ratio(F(2,49=3.078,p=0.049).(3)With task difficulty increasing, compared with normal children, the recognition accuracy of children with learning disability was decreased,(condition1:F(2,47)=3.63, p<0.05; Condition2:F(2,47)=3.79, p<0.05), and the reaction-time was added In digit task (Condition1:F(2,47).93, p <0.05; Condition2:F(2,47)=9.04, p<0.05). In character task, the recognition accuracy of children with learning disability less than the normal group (Condition1:F (2,47)=3.50, p<0.05; Condition2:F(2,47)=4.41, p<0.05), while the reaction time difference was not significant.(4)In the cognitive processing of Chinese characters or digit, the children with learning disability were significantly differences with the normal group in occipital(P1amplitude decreases)、occipito-temporal(N170/VPP amplitude increases) and frontal(LPP amplitude decreases). The learning disability group had no significant difference with normal group in early and late component of the latency components. Conclusions:(1)According to the result of TMT and WCST, the children with learning disabilities were significantly less than normal children in the attention、hand-eye coordination、set transfer and visual-spatial cognition and so on. It means that the children with learning disabilities had the executive dysfunction of frontal lobes or the abnormal phenomena of the level of processing;(2) compared with normal children, the level of digital short-term memory/working memory in children with learning disabilities happened decreases obviously with the task difficulty increases, while the status of character memory had difference. Therefore, the digit and character of memory way in children with learning disabilities were significant difference in normal children;(3) No only Chinese cognitive but also digit processing, the brain area of children with learning disabilities happened abnormal phenomenon obviously include occipital lobes, occipito-temporal area and frontal lobes. The executive dysfunction of the frontal lobes in children with learning disabilities had shortage of self-activation as well as the influence of the other brain question;(4)The cognitive deficits of Chinese dyslexic children was mainly phonological processing disorders, and the dysfunction of Visual-Arabic encoding module was major problems of Chinese dyscalculia children.更多还原