Current Studies

The Children's Vocabulary Project, 2017-2022 

McGregor PI 
Funding provided by the National Institutes of Health 

The objective of this project is to discover how children's word learning changes over developmental time. The central hypothesis is that the challenge of word learning at different ages varies with the word-learning situation, the component of the word to be learned, and the development of underlying cognitive mechanisms. The project designed to test this hypothesis tracks children in Iowa as they learn and retain new words over the course of one week during each of four years beginning in 1st grade. The project involves two specific aims:  

1) to establish a developmental trajectory of word learning in stronger and weaker learns that determines a) how learning and development vary with the learning situation and b) how learning and development vary with the component of the word to be learned 
2) to specify the cognitive mechanisms underlying this developmental trajectory.  

The expected contribution is a more nuanced and comprehensive understanding of word learning challenges and how these challenges change during a crucial developmental period. By addressing this issue, this project will offer new possibilities for tailoring preventive and therapeutic interventions in light of the child's developmental needs.  

Improving STEM Outcomes for Young Children with Language Learning Disabilities by Intervening at the Intersection of Language and Scientific Thought, 2017-2022  

McGregor, PI 
Amanda Van Horne, Susan Wagner Cook, Renee Cole, Co-PIs 
Funding provided by the National Science Foundation 

The sophisticated language of science can be a barrier to the learning of science, and this is especially true for children whose abilities to produce and comprehend language are deficient. The purpose of this project is to test interventions that have the potential to ameliorate language as a barrier to science learning. To isolate the active ingredient, two separate interventions—one addressing grammar and the other addressing vocabulary—will be compared to a science only control condition. The participants will be preschoolers and kindergarteners who have developmental language disorder (DLD) a prevalent condition that impedes the development of vocabulary and grammar. Early intervention could be key to preparing future secondary and post-secondary students with DLD for the successful acquisition of STEM knowledge and the pursuit of STEM careers. The applied objective is to change these students' learning trajectories before significant gaps in scientific knowledge have developed by integrating supports for science-relevant grammar and vocabulary into an early science curriculum. 

The design will be a Randomized Controlled Trial with random assignment of participants to one of three intervention conditions: science only, science + vocabulary supports, and science + grammar supports. Small-group inquiry-based science instruction will occur in all three conditions. The science + vocabulary condition will also include robust instruction on science-related vocabulary words whereas the science + grammar condition will also include focused stimulation of complex grammatical constructions relevant to scientific inquiry. Proximal probes administered weekly during the intervention and withdrawal phases will reveal the participants' mastery and maintenance of taught science concepts. Distal probes administered before and after the intervention phase will reveal the participants' generalization to untaught science concepts and practices. Comparisons of proximal and distal outcomes between conditions will reveal whether supports for vocabulary and grammar improve science learning. 

Early Word Learning, 2011-2022

Munro and Baker, PIs 
Funding provided by the University of Sydney 

We are fortunate to have an ongoing collaboration with Drs. Natalie Munro and Elise Baker in the Faculty of Health Sciences at the University of Sydney. We have been particularly active in exploring word learning in typical toddlers and those who are late to talk. Our long-term goal is to inform early identification and interventions for children at risk for developmental language disorders, broadly defined. 

The following publications have resulted from the project: 

Chami, S., Munro, N., Docking, K., McGregor, K., Arciuli, J., Baker, E. & Heard, R. (2017). Changes in semantic fluency across childhood: normative data from Australian-English speakers. International Journal of Speech-Language Pathology, DOI: 10.1080/17549507.2016.1276214. 

Hodges, R., Baker, E., Munro, N., & McGregor, K. (2016). Responses made by late talkers and typically developing toddlers during verbal assessments. International Journal of Speech-Language Pathology, DOI 10.1080/17549507.2016.1221452. 

Hodges, R., Munro, N., Baker, E., McGregor, K., & Heard, R. (2016). The monosyllable imitation test for toddlers: Influence of stimulus characteristics on imitation, compliance and diagnostic accuracy. International Journal of Language & Communication Disorders, DOI: 10.1111/1460-6984.12249.

Hodges, R., Munro, N., Baker, E. & McGregor, K.K. (2015). The role of elicited verbal imitation in toddlers' word learning. Journal of Child Language, 1-15,DOI: 10.1017/S0305000915000240.