Associations among measures of sequential processing in motor and linguistics tasks in adults with and without a family history of childhood apraxia of speech: A replication study

Abstract

The purpose of this study was to address the hypothesis that childhood apraxia of speech (CAS) is influenced by an underlying deficit in sequential processing that is also expressed in other modalities. In a sample of 21 adults from five multigenerational families, 11 with histories of various familial speech sound disorders, 3 biologically related adults from a family with familial CAS showed motor sequencing deficits in an alternating motor speech task. Compared with the other adults, these three participants showed deficits in tasks requiring high loads of sequential processing, including nonword imitation, nonword reading and spelling. Qualitative error analyses in real word and nonword imitations revealed group differences in phoneme sequencing errors. Motor sequencing ability was correlated with phoneme sequencing errors during real word and nonword imitation, reading and spelling. Correlations were characterized by extremely high scores in one family and extremely low scores in another. Results are consistent with a central deficit in sequential processing in CAS of familial origin.

Keywords:

• sequential processing deficit
• motor speech deficit
• nonword imitation
• nonword decoding
• spelling

Acknowledgments

The authors thank the families whose participation made this study possible. Many thanks to the following undergraduate and graduate students for their assistance with the data collection and analyses: Yayin Chen, Alice Cho, Erica Gonzales, Mariya Legesse, Jonathan Mahaffie, Kyle Middleton, Nancy Nguyen, David Ramm, Kate Sailor and Nancy Yuan. Many thanks to Elias Peter for technical assistance.

Declaration of Interest: The authors gratefully acknowledge the following funding sources: American Speech-Language-Hearing Foundation New Century Scholars Research Grant (B. Peter), NIDCD T32DC00033 (B. Peter), NIDCD 1R03DC010886 (B. Peter) and R01HD054562 (W. H. Raskind). The authors report no conflict of interest.