The structure of executive function and relations with academic achievement in middle childhood [electronic resource]
Keywords: Education.

In recent years, there has been a growing interest in introducing accurate measures of executive function into the classroom context. This interest reflects emerging state and local efforts to hold teachers and schools accountable for student skill development, not just in academics, but also in the foundational skills that support academic achievement, one of which is executive function. Executive function skills are a set of higher-order cognitive skills that include the ability to suppress a prepotent but inappropriate response, the ability to switch between thinking about two different concepts, to think about multiple concepts simultaneously, and the ability to hold and process new and already-stored information. This dissertation reflects an effort to better understand the structure, development, measurement, and correlates of executive function. The dissertation is comprised of four sections, each section focusing on a set of related aims. To address these aims, a structural equation modeling approach was used to analyze data from 806 participants in grades three through five. The first section examines the factor structure of executive function and processing speed as measured by direct assessments in middle childhood. I found that across the full sample, executive function and processing speed were not separable abilities. In addition, children in the full sample did not exhibit separable executive function components, but rather a set of highly overlapping general resource skills reflected in a single latent factor. These findings highlight the importance of examining not only the structure of executive function in middle childhood, but also to model the association between executive function and processing speed during this developmental period. The second section measures structural heterogeneity of executive function/processing speed by grade and by teacher-rated executive function skill level. I found that the structure of executive function/processing speed was invariant across grades. Structural heterogeneity was found, however, between high and low executive function subsamples such that low executive function students, irrespective of grade, demonstrated a single-factor structure. In contrast, high executive function students, irrespective of grade, demonstrated a two-factor structure reflecting a processing speed/inhibitory control factor and a working memory/cognitive flexibility factor. These findings highlight the importance of measuring heterogeneity in structure within classrooms and across grades to assess whether variation is a product of age or cognitive ability. The third section examines whether direct assessments of executive function/processing speed relate to teacher ratings of executive function, and whether certain components of teacher-rated executive function contribute more strongly to variation in direct assessment of executive function/processing speed. I found that teacher ratings of working memory and inhibitory control, but not cognitive flexibility, were positively associated with direct assessments of executive function/processing speed. These findings demonstrate the importance of utilizing multiple assessment strategies when evaluating children's cognitive functioning in order to support students who may perform well under optimal circumstances, but who struggle within a typical classroom environment. The fourth section examines whether directly assessed executive function/processing speed and teacher-rated executive function are associated with student achievement in math and English Language Arts, and whether certain components of executive function/processing speed are more strongly associated with variation in academic performance. I found that teacher-rated EF was more strongly associated with academics than directly assessed EF/PS. Additionally, teacher-ratings of EF were more strongly associated with performance in ELA than in math. Finally, the association between academics and teacher-rated IC and WM was statistically greater in magnitude than the association between academics and teacher-rated CF. Results from this section are consistent with broader findings across the literature linking executive function and academic achievement. The findings contribute to this literature by demonstrating variation in the association between executive function and academics by assessment type and by executive function component. Future research is needed to examine whether these associations are driven by test structure or content in order to inform policy and practice. This dissertation situates these findings within a larger debate around the assessment of skills that support academic achievement. Together, these findings advance our knowledge of how executive function and processing speed develop in middle childhood, and how these skills relate to performance in math and ELA.