Mei Leilei, Xue Gui, Lu Zhong-Lin, He Qinghua, Zhang Mingxia, Wei Miao, Xue Feng, Chen Chuansheng, Dong Qi
Center for Studies of Psychological Application and School of Psychology, South China Normal University, Guangzhou, China; Department of Psychology and Social Behavior, University of California Irvine, Irvine, California, United States of America.
State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China.
PLoS One. 2014 Mar 27;9(3):e93548. doi: 10.1371/journal.pone.0093548. eCollection 2014.
Although behavioral and neuropsychological studies have suggested two distinct routes of phonological access, their neural substrates have not been clearly elucidated. Here, we designed an artificial language (based on Korean Hangul) that can be read either through addressed (i.e., whole word mapping) or assembled (i.e., grapheme-to-phoneme mapping) phonology. Two matched groups of native English-speaking participants were trained in one of the two conditions, one hour per day for eight days. Behavioral results showed that both groups correctly named more than 90% of the trained words after training. At the neural level, we found a clear dissociation of the neural pathways for addressed and assembled phonologies: There was greater involvement of the anterior cingulate cortex, posterior cingulate cortex, right orbital frontal cortex, angular gyrus and middle temporal gyrus for addressed phonology, but stronger activation in the left precentral gyrus/inferior frontal gyrus and supramarginal gyrus for assembled phonology. Furthermore, we found evidence supporting the strategy-shift hypothesis, which postulates that, with practice, reading strategy shifts from assembled to addressed phonology. Specifically, compared to untrained words, trained words in the assembled phonology group showed stronger activation in the addressed phonology network and less activation in the assembled phonology network. Our results provide clear brain-imaging evidence for the dual-route models of reading.
尽管行为学和神经心理学研究表明语音通达存在两条不同的途径，但其神经基础尚未得到明确阐释。在此，我们设计了一种人工语言（基于韩语字母），它既可以通过直接通达（即整词映射）语音，也可以通过拼合（即字素到音素映射）语音来阅读。两组匹配的以英语为母语的参与者分别在两种条件之一中接受训练，每天训练一小时，共训练八天。行为学结果表明，两组在训练后对超过90%的训练单词都能正确命名。在神经层面，我们发现直接通达语音和拼合语音的神经通路存在明显分离：对于直接通达语音，前扣带回皮质、后扣带回皮质、右侧眶额皮质、角回和颞中回的参与度更高；而对于拼合语音，左侧中央前回/额下回和缘上回的激活更强。此外，我们发现了支持策略转换假说的证据，该假说假定随着练习，阅读策略会从拼合语音转换为直接通达语音。具体而言，与未训练的单词相比，拼合语音组中经过训练的单词在直接通达语音网络中表现出更强的激活，而在拼合语音网络中的激活则较少。我们的研究结果为阅读的双通路模型提供了清晰的脑成像证据。
