Thursday, January 20, 2011

Sentence comprehension in children with specific language impairment: The role of phonological working memory

Article: Montgomery, J. (1995). Sentence comprehension in children with specific language impairment: The role of phonological working memory. Journal of Speech and Hearing Research, 38. 187-199.

This study sought to determine the answers to three main research questions and, in doing so aimed to link phonological short-term memory deficiencies to particular language deficiencies in children with specific language impairment (SLI):

1) Do SLI and language matched children differ with respect to their phonological memory capacity as measured by nonword repetition?

2) Do children with SLI show greater difficulty processing longer, linguistically redundant sentences than shorter, nonredundant sentences relative to language-matched children?

3) Is there a relationship between phonological working memory (now referred to as phonological short-term memory) capacity and sentence comprehension?

The results showed that children with SLI repeated longer nonwords less accurately than the language-matched, typically developing control group. As well, children with SLI comprehended fewer longer and redundant sentences (e.g., The big black dog jumped very high.) but did not differ in performance on shorter and nonredundant sentence comprehension (e.g., The dog jumped) than the control group. Finally, Montgomery found a positive correlation between nonword repetition scores (as a measure of phonological short-term memory) and the sentence comprehension measure. That is, subjects with lower scores on nonword repetition also had lower scores on the sentence comprehension task.

This study was one of the first to directly link memory deficiencies in children with SLI to specific linguistic deficits. Strengths of the article include the use of younger language-matched control children. SLI deficits in comparison to this group point to unexpected linguistic deficiencies in the SLI group. The use of redundant and nonredundant sentences (published in the appendix of this article) attempted to isolate the increased memory capacity load of longer sentences, however some of the longer sentences may have added syntactic processing demands. An example of a short sentence was “The girl crying is pushing the boy smiling”, while a long sentence was “The girl who is crying is pushing the boy who is smiling.” Although dated, this article holds well with current literature of SLI and working memory impairments.

Blogger: Laura Vanderlaan is a former Queen’s varsity soccer player and a certified Ontario teacher. She is a research student completing a Masters degree in the LWM lab. Her work is investigating classroom strategies for teaching children with working memory impairments.