Abstract:
Explaining individual differences in vocabulary in autism is critical, as understanding and using words to communicate are key predictors of long-term outcomes for autistic individuals. Differences in audiovisual speech processing may explain variability in vocabulary in autism. The efficiency of audiovisual speech processing can be indexed via amplitude suppression, wherein the amplitude of the event-related potential (ERP) is reduced at the P2 component in response to audiovisual speech compared to auditory-only speech. This study used electroencephalography (EEG) to measure P2 amplitudes in response to auditory-only and audiovisual speech and norm-referenced, standardized assessments to measure vocabulary in 25 autistic and 25 nonautistic children to determine whether amplitude suppression (a) differs or (b) explains variability in vocabulary in autistic and nonautistic children. A series of regression analyses evaluated associations between amplitude suppression and vocabulary scores. Both groups demonstrated P2 amplitude suppression, on average, in response to audiovisual speech relative to auditory-only speech. Between-group differences in mean amplitude suppression were nonsignificant. Individual differences in amplitude suppression were positively associated with expressive vocabulary through receptive vocabulary, as evidenced by a significant indirect effect observed across groups. The results suggest that efficiency of audiovisual speech processing may explain variance in vocabulary in autism.
摘要:
解释自闭症中词汇的个体差异至关重要,因为理解和使用言语交流是自闭症患者长期结果的关键预测因素。视听语音处理的差异可能解释了自闭症词汇的变异性。视听语音处理的效率可以通过幅度抑制来索引,其中,与仅听觉语音相比,响应于视听语音,事件相关电位(ERP)的幅度在P2分量处减小。这项研究使用脑电图(EEG)来测量P2幅度,以响应仅听觉和视听语音以及规范参考,对25名孤独症儿童和25名非孤独症儿童进行词汇测量的标准化评估,以确定振幅抑制(a)是否不同或(b)解释孤独症和非孤独症儿童词汇的变异性.一系列回归分析评估了振幅抑制和词汇评分之间的关联。两组均显示P2振幅抑制,平均而言,相对于仅听觉语音,对视听语音的反应。平均振幅抑制的组间差异无统计学意义。振幅抑制的个体差异通过接受性词汇与表达性词汇呈正相关,两组之间观察到显著的间接效应证明了这一点。结果表明,视听语音处理的效率可以解释自闭症词汇的变化。