Abstract:
Different tasks have been used in examining the neural functional differences associated with developmental dyslexia (DD), and consequently, different findings have been reported. However, very few studies have systematically compared multiple tasks in understanding what specific task differences each brain region is associated with. In this study, we employed an auditory rhyming task, a visual rhyming task, and a visual spelling task, in order to investigate shared and task-specific neural differences in Chinese children with DD. First, we found that children with DD had reduced activation in the opercular part of the left inferior frontal gyrus (IFG) only in the two rhyming tasks, suggesting impaired phonological analysis. Children with DD showed functional differences in the right lingual gyrus/inferior occipital gyrus only in the two visual tasks, suggesting deficiency in their visuo-orthographic processing. Moreover, children with DD showed reduced activation in the left dorsal inferior frontal gyrus and increased activation in the right precentral gyrus across all of the three tasks, suggesting neural signatures of DD in Chinese. In summary, our study successfully separated brain regions associated with differences in orthographic processing, phonological processing, and general lexical processing in DD. It advances our understanding about the neural mechanisms of DD.
摘要:
不同的任务已用于检查与发育性阅读障碍(DD)相关的神经功能差异,因此,报告了不同的发现。然而,很少有研究系统地比较多个任务,以了解每个大脑区域与哪些特定任务差异相关。在这项研究中,我们做了一个听觉押韵任务,视觉押韵任务,和视觉拼写任务,为了调查中国DD儿童的共享和任务特异性神经差异。首先,我们发现,只有在两个押韵任务中,患有DD的儿童在左额下回(IFG)的手术部位的激活减少,提示受损的语音分析。DD患儿仅在两种视觉任务中表现出右舌回/枕下回的功能差异,这表明他们的视觉正交处理存在缺陷。此外,在所有三个任务中,DD患儿的左背下额回激活减少,右脑前回激活增加,提示汉语DD的神经特征。总之,我们的研究成功地分离了与正字法处理差异相关的大脑区域,语音处理,以及DD中的一般词汇处理。它促进了我们对DD的神经机制的理解。