PDF(Pubmed)
Abstract：
During the first year of life, infants start to learn the lexicon of their native language. Word learning includes the establishment of longer-term representations for the phonological form and the meaning of the word in the brain, as well as the link between them. However, it is not known how the brain processes word forms immediately after they have been learned. We familiarized 12-month-old infants (N = 52) with two pseudowords and studied their neural signatures. Specifically, we determined whether a newly learned word form elicits neural signatures similar to those observed when a known word is recognized (i.e., when a well-established word representation is activated, eliciting enhanced mismatch responses) or whether the processing of a newly learned word form shows the suppression of the neural response along with the principles of predictive coding of a learned rule (i.e., the order of the syllables of the new word form). The pattern of results obtained in the current study suggests that recognized word forms elicit a mismatch response of negative polarity, similar to newly learned and previously known words with an established representation in long-term memory. In contrast, prediction errors caused by acoustic novelty or deviation from the expected order in a sequence of (pseudo)words elicit responses of positive polarity. This suggests that electric brain activity is not fully explained by the predictive coding framework.
摘要：
在生命的第一年，婴儿开始学习他们的母语词典。单词学习包括建立语音形式和单词在大脑中的含义的长期表征，以及它们之间的联系。然而,目前还不知道大脑是如何在学习单词后立即处理它们的。我们用两个伪词熟悉了12个月大的婴儿（N=52），并研究了他们的神经特征。具体来说,我们确定新学习的单词形式是否会引起与识别已知单词时观察到的神经特征相似的神经特征(即，当一个成熟的单词表示被激活时，引起增强的不匹配响应），或者对新学习的单词形式的处理是否显示出神经响应的抑制以及学习规则的预测编码原理（即，新词形式的音节顺序)。当前研究中获得的结果模式表明，公认的单词形式引起负极性的不匹配反应，类似于新学习和以前已知的单词，在长期记忆中具有既定的表示形式。相比之下,由声学新颖性或一系列（伪）单词中与预期顺序的偏差引起的预测错误会引起正极性的响应。这表明预测编码框架不能完全解释脑电活动。
