汉语发展性阅读困难儿童的语义启动加工研究

Semantic priming processing in children with Chinese developmental dyslexia

目的:探讨汉语发展性阅读障碍儿童的语义启动加工特性。方法:依据汉语阅读障碍量表、识字量测试、瑞文标准推理测试,从新疆乌恰县某小学筛选出19名柯尔克孜族汉语阅读困难(developmental dyslexia,DD)儿童(DD组),按年龄、智力水平匹配19名同年龄对照组(same chronological age,CA)儿童(CA组),同时按识字量得分和智力水平匹配出20名同等阅读水平对照组(reading level control,RL)儿童(RC组)。采用语义启动范式,测查三组儿童在语义相关、不相关、假字条件下的N400成分的波幅,探查儿童的语义启动加工能力。结果:行为学层面,在语义不相关、假字条件下DD组的准确率显著低于CA组儿童[语义不相关条件:(0.55±0.25),(0.81±0.16);真假字判断条件:(0.43±0.27),(0.68±0.26);均P<0.05],与RL组儿童比较均差异无统计学意义(均P>0.05);三组儿童的反应时比较均差异无统计学意义(F=1.23,2.03,均P>0.05)。脑电层面,语义相关条件下,三组儿童的N400波幅均差异无统计学意义(F=0.55,P>0.05);语义不相关条件下,DD组N400波幅小于CA组[(-5.92±3.70)μV,(-9.76±3.45)μV,P<0.05],与RL组差异无统计学意义[(-5.92±3.70)μV,(-7.41±4.02)μV,P>0.05],CA与RL组差异无统计学意义;假字条件下,DD组N400波幅小于CA组和RL组[(-6.03±2.92)μV,(-9.98±3.40)μV,(-8.91±3.40)μV,均P<0.05],CA与RL组差异无统计学意义。结论:汉语DD儿童存在语义认知加工缺陷,可能是其低阅读水平导致的,而非其固有的;字形加工缺陷是其固有缺陷,提升其汉语学习能力需重视字形教学。

Objective To explore the semantic priming processing characteristics of children with Chinese developmental dyslexia(DD).Methods According to scores of the dyslexia checklist for Chinese children,character recognition test and Raven's standard progressive matrices(RSPM),19 primary school students from a school in Wuqia County of Xinjiang were selected as DD group.Meanwhile,19 children were selected as chronological-age control(CA)group matching in age and RSPM scores,and 20 children were selected as reading-level control(RL)group according to the character recognition test and RSPM scores.The amplitude of N400 of children in three groups were tested by semantic priming paradigm under the conditions of semantic related,unrelated and pseudo words.Results The accuracy of the DD group under the conditions of irrelevant semantics((0.55±0.25)vs(0.81±0.16),P<0.05),and pseudo characters((0.43±0.27)vs(0.68±0.26),P<0.05)were significantly lower than those of CA group.There was no difference between DD group and RL group,as well as between RL group and CA group(both P>0.05).There was no significant difference in the response time among the three groups of children under semantic related and unrelated conditions(F=1.23,2.03,both P>0.05).In terms of ERP data,in semantic related condition,there was no significant difference in N400 amplitude among the three groups(F=0.55,P>0.05).In semantic unrelated condition,the amplitude of N400 in DD group was smaller than that in CA Group((-5.92±3.70)μV vs(-9.76±3.45)μV,P<0.05),and there was no statistically significant difference between DD group and RL Group((-5.92±3.70)μV vs(-7.41±4.02)μV,P>0.05),as well as between CA gorup and RL group.As to pseudo words condition,children in DD group had a lower amplitude of N400 than those in CA and RL groups((-6.03±2.92)μV vs(-9.98±3.40)μV,(-8.91±3.40)μV,both P<0.05).While no significant differences were found between CA group and RL group.Conclusion Children with Chinese DD have cognitive defects in semantic and orthographic processing.The semantic cognitive defects may caused by their low reading level,rather than their inherent defect,while the defect in orthographic processing may be their inherent defect.