Distinguishing Effects of Executive Functions on Literacy Skills in Adolescents

This study investigated direct and indirect effects of executive functions (EF) on reading comprehension in 87 adolescents (mean age = 14.0 years, SD = 1.5). The operation span task was used to measure the updating aspect of working memory, the plus-minus task to measure task-switching, and the numerical Stroop task to measure inhibitory control. Literacy skills tasks assessed nonword decoding, text recall/inference, and passage comprehension. Regression models indicated that EF measures accounted for significant variance in literacy skills after controlling for age and fluid intelligence. Working memory was associated with passage comprehension, task-switching with nonword decoding, and inhibitory control with nonword decoding as well as text recall/inference. Parallel mediation models tested for indirect effects of EF constructs via decoding and text recall/inference. Working memory showed direct and indirect effects on passage comprehension, the latter mediated by text recall/inference. Task-switching was associated with decoding, but its relation to passage comprehension was not significant. Inhibitory control showed indirect effects on passage comprehension via decoding and text recall/inference. Results indicate overlapping but distinct contributions of EF to literacy skills.