Tuesday, April 30, 2019

Mathematical thinking in children with developmental language disorder: the role of pattern skills and verbal working memory

Fyfe, E.R., Matz, L.E,, Hunt, K.M., & Alibali, M.W. (2019). Mathematical thinking in children with developmental language disorder: the role of pattern skills and verbal working memory. Journal of Communication Disorders, 77, 17-30.

This paper examines the role of pattern skills and verbal working memory in mathematics performance in children with developmental language disorder (DLD). Growing evidence suggests that children with DLD have difficulty on mathematics tasks such as counting and arithmetic (see Cross, Joanisse & Archibald, 2019, for a review). Working memory and pattern skills are both known to be associated with mathematical abilities. Some previous studies have identified difficulties with verbal working memory in children with DLD, as well as difficulties learning implicit patterns in statistical learning tasks. The aim of the study was to examine how working memory and pattern skills might contribute to differences in mathematics performance in children with DLD and typically developing (TD) children.

Participants were 36 children aged 6 to 13 years old, eighteen of whom had been identified with DLD. Children completed a battery of tasks assessing verbal working memory, pattern extension, math calculation, and knowledge of math concepts. Verbal working memory was assessed using the Competing Language Processing Task, in which children answered yes/no questions about sentences while also holding the last word of each sentence in memory. In the pattern extension task, children were given 7 elements which varied in shape and size and were asked to identify the 8th shape and explain their reasoning for selecting that shape. The math tasks consisted of math problems involving standard arithmetic (e.g. 2 + 4 + 5 + 2 = __ ), inversion ( e.g. 4 + 7 – 7 = __ ), and equivalence (e.g. 3 + 4 + 6 = 3 + __ ). For each math problem children were asked to explain their strategy, and the authors coded these responses based on whether they demonstrated conceptual understanding of inversion and equivalence.

The authors first used logistic regression to examine differences between the TD and DLD groups on each of the behavioural tasks. They found that, relative to the TD group, the group with DLD performed more poorly on each type of math problem and on the verbal working memory task, but performed similarly on the pattern extension task. A hierarchical regression was then used to examine how math calculation and knowledge of math concepts might each be predicted by pattern extension and working memory. Working memory accounted for some differences in calculation and concepts scores however it did not uniquely predict variance beyond the variance predicted by the group variable. Pattern extension performance did not predict concept scores but uniquely predicted calculation scores, above and beyond the variance predicted by group, age, non-verbal IQ, and working memory.

Overall, these findings suggest that some aspects of poor math performance in DLD may be related to verbal working memory capacity. Additionally, the ability to recognize patterns may support recognition of rules in number sequences, facilitating calculation skills in both TD children and children with DLD. Importantly, the authors acknowledge that their regression models accounted for less than half of the variance in calculation skills and concept knowledge, which suggest there any many other factors that may be contributing to development of mathematics knowledge. In general, these findings highlight that the linguistic and working memory-related factors in DLD can impact performance in many academic areas, despite other intact cognitive processes, including patterning.

Blogger: Alex Cross is an M.Cl.Sc. and Ph.D. Candidate in Speech-Language Pathology, supervised by Dr. Lisa Archibald and Dr. Marc Joanisse.