Froyen Dries J W, Bonte Milene L, van Atteveldt Nienke, Blomert Leo
Faculty of Psychology, University of Maastricht.
J Cogn Neurosci. 2009 Mar;21(3):567-80. doi: 10.1162/jocn.2009.21061.
In transparent alphabetic languages, the expected standard for complete acquisition of letter-speech sound associations is within one year of reading instruction. The neural mechanisms underlying the acquisition of letter-speech sound associations have, however, hardly been investigated. The present article describes an ERP study with beginner and advanced readers in which the influence of letters on speech sound processing is investigated by comparing the MMN to speech sounds presented in isolation with the MMN to speech sounds accompanied by letters. Furthermore, SOA between letter and speech sound presentation was manipulated in order to investigate the development of the temporal window of integration for letter-speech sound processing. Beginner readers, despite one year of reading instruction, showed no early letter-speech sound integration, that is, no influence of the letter on the evocation of the MMN to the speech sound. Only later in the difference wave, at 650 msec, was an influence of the letter on speech sound processing revealed. Advanced readers, with 4 years of reading instruction, showed early and automatic letter-speech sound processing as revealed by an enhancement of the MMN amplitude, however, at a different temporal window of integration in comparison with experienced adult readers. The present results indicate a transition from mere association in beginner readers to more automatic, but still not "adult-like," integration in advanced readers. In contrast to general assumptions, the present study provides evidence for an extended development of letter-speech sound integration.
在透明字母语言中，完全掌握字母-语音关联的预期标准是在接受阅读教学的一年内。然而，字母-语音关联习得背后的神经机制几乎未被研究过。本文描述了一项针对初学者和高级阅读者的ERP研究，其中通过比较对单独呈现的语音的失匹配负波（MMN）和对伴有字母的语音的MMN，来研究字母对语音处理的影响。此外，还对字母和语音呈现之间的刺激呈现间隔（SOA）进行了操控，以研究字母-语音处理整合时间窗口的发展情况。初学者尽管接受了一年的阅读教学，但并未表现出早期的字母-语音整合，即字母对语音诱发MMN没有影响。只有在稍后的650毫秒的差异波中，才揭示出字母对语音处理的影响。接受了4年阅读教学的高级阅读者，表现出早期且自动的字母-语音处理，这表现为MMN波幅增强，然而，与有经验的成年阅读者相比，其整合的时间窗口不同。目前的结果表明，从初学者单纯的关联过渡到高级阅读者更自动但仍非“成人般”的整合。与一般假设相反，本研究为字母-语音整合的长期发展提供了证据。
