Title: Comparing tense and agreement productivity in boys with fragile X syndrome, children with developmental language disorder, and children with typical development
Legend: Pattern of tense and agreement productivity across boys with fragile X syndrome (FXS), children developmental language disorder (DLD), and children with typical development (TD). The solid line indicates the median and the cross indicates the mean.
Citation: Hilvert, E., Hoover, J., Sterling, A., & Schroeder, S. (2020). Comparing tense and agreement productivity in boys with fragile X syndrome, children with developmental language disorder, and children with typical development. Journal of Speech, Language, and Hearing Research, 63, 1181-1194. doi:10.1044/2019_JSLHR-19-00022.
Abstract: Purpose: The present study compared and characterized the tense and agreement productivity of boys with fragile X syndrome (FXS), children with developmental language disorder (DLD), and children with typical development (TD) matched on mean length of utterance (MLU). Methods: Twenty-two boys with FXS (Mage = 12.22 years), 19 children with DLD (Mage = 4.81 years), and 20 children with TD (Mage = 3.23 years) produced language samples that were coded for their productive use of five tense markers (i.e., third person singular, past tense -ed, copula be, auxiliary be, and auxiliary do) using the Tense and Agreement Productivity score (Hadley & Short, 2005). Children also completed norm-referenced cognitive and linguistic assessments. Results: Children with DLD generally used tense and agreement markers less productively than children with TD, particularly third person singular and auxiliary be. However, boys with FXS demonstrated a more complicated pattern of productivity, where they were similar to children with DLD and TD, depending on the tense marker examined. Results revealed that children with DLD and TD showed a specific developmental sequence of the individual tense markers that aligns with patterns documented by previous studies (e.g., Gladfelter & Leonard, 2013), whereas boys with FXS demonstrated a more even profile of productivity.
Conclusions: These findings help to further clarify areas of overlap and discrepancy in tense and agreement productivity among boys with FXS and children with DLD. Additional clinical implications of these results are discussed.
About the Lab: Audra Sterling is an Associate Professor in the Department of Communication Sciences and Disorders. Her research examines the contributions of both biology and environment in the development of language and cognition in children with developmental disabilities. Visit the Research in Developmental Disabilities Language Lab for more information: https://riddl.waisman.wisc.edu