Zuk Jennifer, Iuzzini-Seigel Jenya, Cabbage Kathryn, Green Jordan R, Hogan Tiffany P
Department of Communication Sciences and Disorders, MGH Institute of Health Professions, Boston, MA.
Program in Speech and Hearing Bioscience and Technology, Division of Medical Sciences, Harvard University, Boston, MA.
J Speech Lang Hear Res. 2018 Mar 15;61(3):583-592. doi: 10.1044/2017_JSLHR-S-16-0106.
Childhood apraxia of speech (CAS) is hypothesized to arise from deficits in speech motor planning and programming, but the influence of abnormal speech perception in CAS on these processes is debated. This study examined speech perception abilities among children with CAS with and without language impairment compared to those with language impairment, speech delay, and typically developing peers.
Speech perception was measured by discrimination of synthesized speech syllable continua that varied in frequency (/dɑ/-/ɡɑ/). Groups were classified by performance on speech and language assessments and compared on syllable discrimination thresholds. Within-group variability was also evaluated.
Children with CAS without language impairment did not significantly differ in syllable discrimination compared to typically developing peers. In contrast, those with CAS and language impairment showed significantly poorer syllable discrimination abilities compared to children with CAS only and typically developing peers. Children with speech delay and language impairment also showed significantly poorer discrimination abilities, with appreciable within-group variability.
These findings suggest that speech perception deficits are not a core feature of CAS but rather occur with co-occurring language impairment in a subset of children with CAS. This study establishes the significance of accounting for language ability in children with CAS.
言语失用症(CAS)被认为源于言语运动计划和编程方面的缺陷,但CAS中异常言语感知对这些过程的影响存在争议。本研究比较了患有和未患有语言障碍的CAS儿童与患有语言障碍、言语延迟的儿童以及发育正常的同龄人之间的言语感知能力。
通过辨别频率变化的合成语音音节连续体(/dɑ/-/ɡɑ/)来测量言语感知。根据言语和语言评估的表现对各组进行分类,并比较音节辨别阈值。还评估了组内变异性。
未患语言障碍的CAS儿童在音节辨别方面与发育正常的同龄人没有显著差异。相比之下,患有CAS和语言障碍的儿童与仅患有CAS的儿童以及发育正常的同龄人相比,音节辨别能力明显较差。患有言语延迟和语言障碍的儿童的辨别能力也明显较差,且组内变异性明显。
这些发现表明,言语感知缺陷不是CAS的核心特征,而是在一部分患有CAS的儿童中与并发的语言障碍一起出现。本研究确立了在患有CAS的儿童中考虑语言能力的重要性。