Wu Chiao-Yi, Koh Jia Ying Serene, Ho Moon-Ho Ringo, Miyakoshi Makoto, Nakai Toshiharu, Chen Shen-Hsing Annabel
Division of Psychology, School of Humanities and Social Sciences, Nanyang Technological University, Singapore.
Swartz Center for Computational Neuroscience, Institute for Neural Computation, University of California San Diego, United States; Neuroimaging and Informatics Lab, National Center for Geriatrics and Gerontology, Ohbu, Aichi, Japan; Japan Society for the Promotion of Sciences, Japan.
Brain Lang. 2014 Aug;135:32-41. doi: 10.1016/j.bandl.2014.04.005. Epub 2014 Jun 2.
Reading is a complex process involving neural networks in which connections may be influenced by task demands and other factors. We employed functional magnetic resonance imaging and dynamic causal modeling to examine age-related influences on left-hemispheric kanji reading networks. During a homophone judgment task, activation in the middle frontal gyrus, and dorsal and ventral inferior frontal gyri were identified, representing areas involved in orthographic, phonological, and semantic processing, respectively. The young adults showed a preference for a semantically-mediated pathway from orthographic inputs to the retrieval of phonological representations, whereas the elderly preferred a direct connection from orthographic inputs to phonological lexicons prior to the activation of semantic representations. These sequential pathways are in line with the lexical semantic and non-semantic routes in the dual-route cascaded model. The shift in reading pathways accompanied by slowed reaction time for the elderly might suggest age-related declines in the efficiency of network connectivity.
阅读是一个涉及神经网络的复杂过程，其中的连接可能会受到任务需求和其他因素的影响。我们采用功能磁共振成像和动态因果模型来研究年龄对左半球汉字阅读网络的影响。在同音判断任务中，我们识别出了额中回、额下回背侧和腹侧的激活，分别代表参与正字法、语音和语义处理的区域。年轻人表现出倾向于从正字法输入到语音表征检索的语义介导途径，而老年人则更喜欢在语义表征激活之前从正字法输入到语音词典的直接连接。这些顺序途径与双路级联模型中的词汇语义和非语义途径一致。老年人阅读途径的转变伴随着反应时间的延长，这可能表明与年龄相关的网络连接效率下降。
