发展性阅读障碍儿童听觉功能的事件相关电位研究

An auditory events related potential study on chinese children with developmental dyslexia

目的探讨发展性阅读障碍儿童听觉功能的神经心理学特性,研究其听觉功能与正常儿童的差异,进一步探讨与阅读障碍儿童的神经结构特征。方法本实验设计利用频率500Hz和1000Hz的2个纯音刺激激活大脑听觉神经系统的活动,同时使用ERP分析系统记录被试完成简单听觉任务的波形。结果1.听觉ERP波形为头皮前部一个大的负波,又可表述为四个相对独立的成分P60,N160,P200和N240;2.对纯音的加工有显著的左右半球差异;3.阅读障碍儿童在听觉加工的ERP波形上与正常儿童相比表现为潜伏期的显著延迟以及波幅的明显降低阅读障碍儿童N160的峰潜伏期长于正常儿童,分别为(182.8±5.9)ms和(166.6±5.9)ms;而且,阅读障碍儿童的波幅低于正常儿童。结论阅读障碍儿童的听觉系统发育可能落后于正常儿童,主要表现为峰潜伏期的显著延迟以及波幅的明显降低,这可能是阅读障碍儿童听觉系统功能发育的主要神经心理学特性。

Objective To explore the neuropsychological feature of developmental dyslexia, especially in auditory sensitivity. Methods 500Hz and 1000Hz pure tones auditory stimuli were presented and the scalp potentials were recorded by ERP analyses system. Results Firstly, auditory-related brain potential was a large negative wave form, which could include four waves, respectively as P60, N160, 19200, and N240. Secondly, there is a significantly left-right hemispheric difference in processing pure tone. Thirdly, comparing with normal, the auditory-related brain potential of dyslexia expressed as the delay of latency and the descent of amplitude. Conclusion The development of auditory system in dyslexia maybe more delays than normal children. The significant delay of latency and the marked descent of amplitude perhaps is the main neuropsychologieal character in auditory system of dyslexia.