Clarke, Jennifer D.. Development of speech motor control for language: motor analysis from phonetic transcripts. Retrieved from https://doi.org/doi:10.7282/t3-qp1y-px13
DescriptionThe developmental sequence of speech motor control has yet to be directly examined in the emergence of spoken language. Contemporary accounts of the emergence of spoken language traditionally address speech motor control as part of the maturational process. The present study investigates the developmental sequence of speech motor control in the transition from babble to word productions.
Speech motor control of the jaw, lips, and tongue was observed longitudinally from nine to 16 months of age in five English speaking children. Predictions of speech motor control were evaluated for spontaneous vocalizations from the production of babble to referential words.
Results confirmed that speech sound productions in babble and words at the onset of spoken language are controlled with the child’s available motor skills. As predicted, the jaw was the first of the three articulators to have independent graded control in the emergence of word productions. Lip control was observed second as the child began producing referential words. At 16 months there was no evidence of independent tongue control in the production of babble, words, or referential words.
These findings indicate that speech production at the onset of spoken language is enabled by the motor control available to the child. The results of this study add an additional variable to be considered in theoretical perspectives that attempt to explain the onset of spoken language.
Early developmental milestones of the speech motor system have yet to be identified in the emergence of spoken language. The results of this study identify the motor milestones for the jaw and the lip at the onset of word productions. These findings provide a first step in investigation of speech motor control and a basis for investigating therapeutic approaches that consider these skills.