Sadagopan Neeraja, Smith Anne
Department of Speech, Language, and Hearing Sciences, Purdue University, 1353 Heavilon Hall, 500 Oval Drive, West Lafayette, IN 47907-2038, USA.
J Speech Lang Hear Res. 2008 Oct;51(5):1138-51. doi: 10.1044/1092-4388(2008/06-0222). Epub 2008 Jul 29.
The authors examined the effects of utterance length and linguistic complexity on speech movement consistency for 210 participants between the ages of 5 and 22 years. Variability and durational analyses were conducted to (a) determine a more complete picture of the developmental course of earlier observations of the effects of linguistic constructs on speech motor variability and (b) describe trends for duration of the same sequence of words in different sentential contexts across development.
Lower-lip movement was recorded during the production of "buy Bobby a puppy" spoken in isolation as well as embedded as a phrase in 2 longer, more complex sentences.
Compared with young adults, children demonstrated higher variability in producing repeated movement sequences for the target word sequence across all conditions. Also, for all age groups except young adults, increased processing demands resulted in significantly increased movement trajectory variability. Duration analyses suggest that around age 9 years, children begin to use adult-like pre-speech processes to plan the timing of sentence internal phrases, and maturation of these planning processes continues through late adolescence.
These results provide further evidence for language-motor interactions and for a protracted course of speech motor development that continues well into adolescence.
作者研究了话语长度和语言复杂性对210名年龄在5至22岁之间参与者言语运动一致性的影响。进行了变异性和时长分析，以（a）更全面地了解早期关于语言结构对言语运动变异性影响观察的发展过程，以及（b）描述不同句子语境中相同单词序列在整个发展过程中的时长趋势。
在单独说出“给博比买只小狗”以及将其作为一个短语嵌入到2个更长、更复杂的句子中时，记录下唇运动。
与年轻成年人相比，儿童在所有条件下针对目标单词序列产生重复运动序列时表现出更高的变异性。此外，对于除年轻成年人之外的所有年龄组，加工需求增加导致运动轨迹变异性显著增加。时长分析表明，大约在9岁时，儿童开始使用类似成人的言语前过程来规划句子内部短语的时间，并且这些规划过程的成熟持续到青春期后期。
这些结果为语言 - 运动相互作用以及持续到青春期的长期言语运动发展过程提供了进一步的证据。
