Acoustic analysis of bilingual children’s speech (León et al., 2022)

<strong>Purpose: </strong>The aim of this study was to characterize speech acoustics in bilingual preschoolers who speak Jamaican Creole (JC) and English. We compared a standard approach with a culturally responsive approach for characterizing speech sound productions. Preschoolers’ speech productions were compared to adult models from the same linguistic community as a means for providing confirmatory evidence of typical speech patterns specific to JC–English speakers. <strong>Method: </strong>Two protocols were applied to the data collected using the Diagnostic Evaluation of Articulation and Phonology (DEAP) Articulation subtest: (a) the standardized DEAP protocol and (b) a culturally and linguistically adapted protocol reflective of the Jamaican post-Creole (English to Creole) continuum. The protocols were used to analyze responses from JC-English–speaking preschoolers (<em>n</em> = 119) and adults (<em>n</em> = 15). Responses were analyzed using acoustic (voice onset time, whole-word duration, and vowel duration) and perceptual (percentage of consonant correct–revised and response frequencies) measures. <strong>Results: </strong>The culturally responsive protocol captured variation in the frequency and acoustic differences produced in the post-Creole continuum, with higher amounts of “other” responses compared to “standard” target responses for both children and adults. Adults’ whole-word durations were shorter and showed more consistent prevoicing during initial plosives compared to the children. <strong>Conclusions: </strong>Applying culturally responsive methods, including knowledge of the variation produced in the post-Creole continuum and with adult models from the same linguistic community, improved the ecological validity of speech characterizations for JC–English preschoolers. Acoustic properties of speech should be investigated further as a means of describing bilingual development and distinguishing between difference and disorder. <br> <strong>Supplemental Material S1.</strong> Frequency (most to least) of children’s response variation. <br> León, M. Washington, K. N., McKenna, V. S., Crowe, K., &amp; Fritz, K. (2022). Linguistically informed acoustic and perceptual analysis of bilingual children’s speech productions: An exploratory study in the Jamaican context. <em>Journal of Speech, Language, and Hearing Research</em>. Advance online publication. https://doi.org/10.1044/2022_JSLHR-21-00386

**研究目的：** 本研究旨在刻画使用牙买加克里奥尔语（Jamaican Creole, JC）与英语的双语学龄前儿童的言语声学特征。本研究对比了两种用于刻画言语语音产出特征的方法：标准化方案与文化适配性方案。研究将学龄前儿童的言语产出与同一语言社群的成人范本进行比对，以期为牙买加克里奥尔语-英语使用者特有的典型言语模式提供验证性证据。

**方法：** 本研究针对由语音清晰度与音系诊断评估（Diagnostic Evaluation of Articulation and Phonology, DEAP）语音分测验采集的数据，采用两套分析方案：(a) 标准化DEAP方案；(b) 适配牙买加克里奥尔语-英语连续体（英语向克里奥尔语过渡）的文化与语言适配方案。研究使用上述两套方案，对119名使用JC-英语的学龄前儿童（n=119）及15名成人（n=15）的应答数据进行分析。分析指标涵盖声学指标（嗓音起始时间、整词时长与元音时长）与感知指标（修正后辅音正确百分比与应答频率）。

**结果：** 文化适配性方案成功捕捉到了克里奥尔语-英语连续体中言语产出的频率与声学差异，相较于“标准”靶应答，儿童与成人组的“其他”类应答占比均显著更高。与儿童组相比，成人组的整词时长更短，且初始爆破音的送气前现象更为一致。

**结论：** 采用文化适配性方法——包括对克里奥尔语-英语连续体中产出变异的认知，以及使用同一语言社群的成人范本——显著提升了针对JC-英语学龄前儿童言语特征刻画的生态效度。未来应进一步探究言语声学属性，以精准描述双语发育进程，并区分发育差异与言语障碍。

**补充材料S1：** 儿童应答变异的频率分布（由高至低）。

León, M., Washington, K. N., McKenna, V. S., Crowe, K., & Fritz, K. (2022). 双语儿童言语产出的语言学导向声学与感知分析：牙买加语境下的探索性研究。 *Journal of Speech, Language, and Hearing Research*. 在线优先出版。https://doi.org/10.1044/2022_JSLHR-21-00386