Jones Samuel David, Brandt Silke
Department of Linguistics and English Language, Lancaster University, United Kingdom.
J Speech Lang Hear Res. 2019 Aug 15;62(8):2847-2854. doi: 10.1044/2019_JSLHR-L-18-0468. Epub 2019 Jul 22.
Purpose This study reexamines the claim that difficulty forming memories of words comprising uncommon sound sequences (i.e., low phonological neighborhood density words) is a determinant of delayed expressive vocabulary development (e.g., Stokes, 2014). Method We modeled communicative development inventory data from (N = 442) 18-month-old children, with expressive lexicon sizes between 0 and 517 words (Mdn = 84). We fitted a Bayesian regression model in which the production of each communicative inventory word (N = 680) by each child was predicted by interactions between that child's expressive lexicon size and the word's (a) phonological neighborhood density, (b) frequency in child-directed speech, (c) length, (d) babiness, and (e) concreteness. Results Children with larger expressive lexicons were more likely to produce words comprising uncommon sound sequences than age-matched children with smaller lexicons. However, the magnitude of the interaction between expressive lexicon size and phonological neighborhood density was modest relative to interactions between expressive lexicon size and word frequency, length, babiness, and concreteness. Conclusion Emphasis on a difficulty with the memorization of low-neighborhood density words as a determinant of slow vocabulary growth may be unwarranted, and the current evidence base in this direction is not robust enough to strongly support the development of possible interventions for late talkers.
目的 本研究重新审视了一种观点，即难以形成由不常见语音序列组成的单词（即低语音邻域密度单词）的记忆是延迟表达性词汇发展的一个决定因素（例如，斯托克斯，2014年）。方法 我们对来自442名18个月大儿童的交流发展量表数据进行了建模，这些儿童的表达性词汇量在0到517个单词之间（中位数为84）。我们拟合了一个贝叶斯回归模型，其中每个孩子对每个交流量表单词（共680个）的产出由该孩子的表达性词汇量与该单词的以下因素之间的相互作用来预测：（a）语音邻域密度、（b）儿童导向言语中的频率、（c）长度、（d）幼稚度和（e）具体性。结果 与年龄匹配但词汇量较小的儿童相比，表达性词汇量较大的儿童更有可能产出由不常见语音序列组成的单词。然而，相对于表达性词汇量与单词频率、长度、幼稚度和具体性之间的相互作用而言，表达性词汇量与语音邻域密度之间相互作用的程度较小。结论 将难以记忆低邻域密度单词作为词汇增长缓慢的一个决定因素可能是没有根据的，而且目前在这个方向上的证据基础不够有力，不足以有力地支持为说话较晚的儿童开发可能的干预措施。
