Semantic priming processing in children with Chinese developmental dyslexia / 中华行为医学与脑科学杂志

ABSTRACT

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.