汉语发展性阅读障碍儿童不同听觉刺激模式下事件相关电位特征分析

The Characteristics of Event-related Potential in Chinese Dyslexia with Different Stimulus Modes

目的比较汉语发展性阅读障碍(development dyslexia,DD)儿童和正常对照组儿童失匹配负波(mismatch negativity,MMN)、P1-N1c-N2的差异,探讨发展性阅读障碍儿童不同听觉刺激模式下事件相关电位的特征。方法在标准刺激(纯音,上升时间15 ms,强度75 dB SPL,持续时间200 ms,P=0.85)的基础上,分别调整刺激声的上升时间、强度和持续时间形成三种偏差刺激(P=0.15),采用被动Oddball范式对22例汉语DD儿童(DD组)和31例正常对照儿童(对照组)进行脑电图(EEG)采集,比较DD组和对照组MMN与P1-N1c-N2成分的差异。结果 FCz电极点的分析:①DD组上升时间偏差刺激(P=0.026<0.05)和持续时间偏差刺激下(P=0.037<0.05)MMN波幅均小于对照组;②DD组中上升时间偏差刺激P1潜伏期较标准刺激延迟(P=0.011<0.05),而对照组中差异不显著;③DD组上升时间偏差刺激N2波幅小于标准刺激(P=0.002<0.01),而对照组差异不显著;④DD组持续时间偏差刺激N2波幅小于标准刺激(P<0.001),而对照组差异不显著。FT7和FT8电极N1c波幅存在差异,DD组持续时间偏差刺激N1c波幅小于标准刺激(P=0.009<0.05),而对照组差异不显著,其他交互作用不显著。结论发展性阅读障碍儿童的听觉分辨能力较正常儿童差,上升时间偏差刺激和持续时间偏差刺激下MMN和P1-N1c-N2潜伏期延长、波幅降低,发展性阅读障碍儿童可能存在听觉感知障碍。

Objective To compare the differences of mismatch negativity(MMN) and P1-N1 c-N2 between children with developmental dyslexia(DD) and control children, and to explore the characteristics of event-related potentials in children with DD under different auditory stimulation modes. Methods On the basis of standard stimulus(500 Hz pure tone,P=0.85),three kinds of deviants(P=0.15) were formed by adjusting the rise time, intensity and duration time respectively.EEG was collected from 22 children with dyslexia(the dyslexia group) and 31 control children(the control group) using passive Oddball paradigm. MMN and P1-N1 c-N2 components were compared between the dyslexia and the control groups.Results An analysis of FCz electrode points found out that the MMN amplitude of rise time deviation stimulation(P=0.026,P<0.05) and duration deviation stimulation(P=0.037,P<0.05) in the dyslexia group were smaller than those in the control group. The latency of rise time deviation stimulation P1(P=0.011,P<0.05) in the dyslexia group was delayed compared with the standard stimulation, but there was no significant difference in the control group. The N2 wave was stimulated by rise time deviation stimulation in the dyslexia group. The amplitude of N2 stimulation was less than that of standard stimulation(P=0.002,P<0.01),but there was no significant difference between the control group and the dyslexia group. The duration deviation stimulation N2 amplitude was less than that of standard stimulation(P<0.001),but there was no significant difference between the control group and the dyslexia group. There were differences in N1 c amplitudes between FT7 and FT8 electrodes. The duration deviation stimulus N1 c amplitude(P=0.009,P<0.05) of dyslexia group was smaller than that of the standard stimulus, but there was no significant difference between the control group and other interactions.Conclusion The children with developmental dyslexia have lower auditory discrimination than normal children. The latency of MMN and P1-N1 c-N2 is prolonged, and the amplitude is decreased under the stimulus of rise time deviants and duration deviants. The children with developmental dyslexia may have auditory perception impairment.