Jacob, R., & Parkinson, J. (2015). The potential for school-based interventions that target executive function to improve academic achievement: A review. Review of Educational Research. Advance online publication. doi:10.3102/0034654314561338
Recent years have witnessed increased interest in executive functions (EFs), their relation to academic achievement, and whether academic interventions can target EFs to boost effectiveness and improve academic outcomes. In the reviewed study, Jacob and Parkinson (2015) summarize research investigating these questions and analyze whether there is evidence for a causal relationship between EFs and academic achievement.
Broadly understood, EFs represent domain-general cognitive skills that regulate goal-directed behaviors. Students (and adults) use EFs on any task that requires them to concentrate, plan a course of action, solve a problem, coordinate, make choices, or override a strong internal or external pull (Diamond, 2006). Reading and math represent complex skills that require many of these cognitive tasks. For example, when reading, skilled readers must set a goal, develop a plan or strategy to meet that goal, monitor their comprehension of the material, avoid distractors, shift their attention to newly emerging information or requirements, and evaluate whether their goals were accomplished.
Jacob and Parkinson identify and define four separable EF skills: response inhibition, attention control, attention shifting, and working memory. Response inhibition is the ability override an automatic response. For example, a classic test of response inhibition (the Stroop) requires the examinee to identify colors and establish a response pattern. In subsequent trials, the examinee is required to read the words of colors printed in incongruent ink (e.g., the word red printed in blue ink). To complete this task, the examinee must ignore (or inhibit) the color of the ink and read only the printed word. Attention control is the ability to concentrate and ignore distractions. In the case of reading, attention control might manifest as the ability to tune out environmental noise to concentrate or to focus on the main idea of a question or passage without getting distracted by less important details. In contrast, attention shifting is the ability to shift the focus of one's attention while ignoring other distractors. Attention shifting is necessary to switch between problem-solving rules or techniques, such as switching between subtraction and multiplication on a worksheet with multiple types of math problems. Working memory is the ability to maintain information and manipulate that information. This skill is imperative to mental math and reading tasks, as students retain information about a previous word or phrase long enough to link it meaningfully with the words that follow. Although there are different ways to conceptualize EF, each of the skills that Jacob and Parkinson researched has been implicated in previous research as a potential predictor of academic achievement or other goal-oriented outcomes. The reviewed study summarizes that research, which was conducted with school-age children.
In the reviewed study, Jacob and Parkinson combine the results from 67 studies to answer the following three research questions:
Across studies, the average correlation between reading achievement and EFs was .30 for reading and .31 for math, meaning that the relationship between EFs and student achievement is weak to medium-strong. Importantly, these correlations do not account for other variables that may influence both EFs and academic achievement. Thus, it is possible that unmeasured variables (e.g., socioeconomic status, language ability, IQ) could explain the association between EFs and academic achievement. For example, perhaps students with high IQ, and thus high academic achievement, have strong EF skills as a result of their high IQ. It is also possible that higher academic achievement in fact causes improved performance on EF tasks, as opposed to the hypothesized relation in which EFs contribute to academic achievement. We cannot determine the direction (or causality) of the EF–achievement relationship using only correlations.
Correlations were examined to determine whether the relation between EFs and achievement differs across different ages or achievement measures (reading or math). Results revealed few differences as a function of age, achievement area, or the specific EF measured. This finding means that the correlation between EFs and math achievement is as strong as the correlation between EFs and reading achievement. The strength of these relationships does not change as children progress through their education.
Jacob and Parkinson found little evidence to support the existence of a causal relation between EFs and achievement. Five studies used random assignment to evaluate the effects of an intervention targeting EFs, investigating 13 relations between EF training and academic achievement. Of these 13 analyses, only one effect was positive and statistically significant. Thus, in rigorous experimental studies of the effects of EF training on achievement, results reveal improvements in EFs but not corresponding increases in achievement. The authors conclude that there is little evidence that stronger EFs cause higher achievement.
There is considerable research on the relations of EFs and academic achievement. Recently, this research has begun to receive attention among school psychologists, teachers, and parents, and several intensive, potentially expensive EF training programs have been developed (e.g., Tools of the Mind, Head Start's REDI program). As with any novel intervention target for students, particularly students who exhibit academic difficulties, there is enthusiasm to adopt and apply "the latest" in educational and psychological research.
However, such enthusiasm should be tempered by objective evaluation of the available evidence. The findings of this study present a useful reminder of the high bar for establishing evidence-based practices in education. Although there is considerable potential in research on EFs and future studies may demonstrate that EF training improves the effectiveness of math and literacy interventions, the evidence base at present does not support widespread adoption of intensive EF training programs. Many questions remain about the nature of EFs, including how to measure EFs, what interventions improve EFs, and whether an improvement in EFs causes an improvement in academic skill.
Diamond, A. (2006). The early development of executive functions. In E. Bialystok & F. Craik (Eds.), Lifespan cognition: Mechanisms of change (pp. 70–95). New York, NY: Oxford University Press.