Electronic Thesis and Dissertation Repository


Doctor of Philosophy


Health and Rehabilitation Sciences


Archibald, Lisa M. D.


Children with disproportionate deficits in language, known as Specific Language Impairment (SLI), often demonstrate deficits in nonverbal cognitive abilities, such as working memory. Such findings have prompted much debate on the association between language and working memory functioning. The primary aim of this thesis was to examine the connection between working memory and language abilities among children with specific or combined impairments in these domains. Study 1 examined the potential of narrative retell performance to indicate impairment in language or working memory among 17 children with specific or combined impairment in language or working memory as well as 9 controls. Quantitative analysis using logistic regression revealed that language impairment was predicted best by the interaction between mean length of utterance, percent grammatical utterances, and age, whereas working memory impairment was best predicted by the interaction between events recalled and subordinate clauses per utterance. Exploratory qualitative analysis using qualitative descriptors differentiated narratives of children with and without impairment and revealed clusters of descriptors that identified contrasting speaking styles. Study 2 tested domain-specific interventions in language or working memory using a single subject design. Chapter 3 reports the effects of a narrative-based language intervention for 10 children with language impairment with or without working memory impairment. Results showed gains on narrative ability for most participants, and broader linguistic gains for half of the participants. Intervention effects on related domains (i.e., working memory, reading, math) were evident for some participants as well. Chapter 4 reports the effects of a working memory training program for 7 children with working memory impairment with or without language impairment. Results showed training effects on working memory tasks similar to training tasks for all participants. Transfer to language ability was seen for 4 participants, and transfer to reading or math was evident for 3 participants. Responder analyses for Study 2 showed associations between intervention effectiveness and baseline cognitive abilities, age, speaking style, and intervention intensity. Results support the view that working memory and language are separable but closely related cognitive processes. Responder analyses highlight the importance of considering heterogeneity among children with impairments in research and clinical settings.