Difference or Delay? Syntax, Semantics, and Verb Vocabulary Development in Typically Developing and Late-talking Toddlers

ABSTRACT

While semantic and syntactic properties of verb meaning can impact the success of verb learning at a single age, developmental changes in how these factors influence acquisition are largely unexplored. We ask whether the impact of syntactic and semantic properties on verb vocabulary development varies with age and language ability for toddlers aged 16 to 30 months in a large sample (N = 5520, N_{Late Talkers} = 821; N_{Typically Developing} = 4699, cutoff = 15^th percentile) of vocabulary checklist data from the MacArthur-Bates Communicative Development Inventory (MBCDI). Verbs from the MBCDI were coded for their syntactic and semantic properties, including manner/result meanings, durative/punctual events, and syntactic complexity. Both late talkers and typically developing children were less likely to produce syntactically complex verbs at younger ages as compared to older ages. Group differences emerged for manner/result: Typically developing children were more likely to produce manner verbs at all ages, but late talkers were more likely to produce result verbs. Regardless of group, children who produced more manner versus result verbs also had larger verb vocabulary sizes overall. These results suggest that late talkers and typically developing toddlers differ in how they build their verb vocabularies.

Acknowledgments

This work was partially supported by HD052120 to AB, T32 DC000030 to SH, and F31 DC018435 to JBK.

Notes

¹ In conducting our post-hoc analyses, we observed that children – both LT and TD – with a manner dominance also had larger overall MBCDI vocabulary sizes as compared to those with a result dominance (manner dominance: M = 330, SD = 181, N = 2621; result dominance: M = 231, SD = 199, N = 1813; t(4432) = 17.4, p < .001). A linear regression predicting the total vocabulary size from a three-way interaction of age (centered), group (LT or TD) and dominance yielded an identical pattern of results to our regression predicting verb vocabulary size. Age (b = 13, p < 0.001), group (b = 55, p < .001) and their interaction (b = 30, p < .001) were all significant, as was the three-way interaction between age, group, and dominance (b = −4.4, p < .001). Children with manner dominance have not only larger verb vocabularies but larger vocabularies overall.

Additional information

Funding

This work was supported by the Eunice Kennedy Shriver National Institute of Child Health and Human Development [HD052120]; and the National Institute on Deafness and Other Communication Disorders [F31 DC018435,T32 DC000030].