Abstract
This brief leverages the first ever nationally representative data set with a direct assessment of elementary school-aged children’s executive function skills to examine racial and socioeconomic gaps in performance. The analysis reveals large gaps in measures of working memory and cognitive flexibility, the two components of executive function included in the Early Childhood Longitudinal Study, Kindergarten Class of 2010–11 (ECLS-K:2011), based on racial group membership and socioeconomic status. Children’s initial gaps on entry into kindergarten in executive function measures are generally lower than gaps in measures of math and reading achievement. Furthermore, as children progress to the end of second grade, gaps in executive function skills commonly narrow for Black and Hispanic students as well as each socioeconomic status quintile. Implications and directions for future research are discussed.
Keywords
In recent decades, the evidence of the importance of so-called noncognitive skills has burgeoned (Tough, 2013). These skills, which include constructs like grit, motivation, and self-control, have dominated education discourse (Blad, 2015; Tough, 2013, 2016). Noncognitive skills are even making their way into policy, with the CORE districts in California including measures of students’ growth mindset, self-efficacy, self-management, and social awareness in their accountability system (Tough, 2016). Furthermore, the Every Student Succeeds Act (ESSA) opens the door for the expansion of noncognitive skills in accountability systems nationwide with the requirement that states include one nonacademic measure. This brief provides new, nationally representative evidence on a particular set of skills that are foundational to numerous noncognitive abilities—executive function.
Executive function skills help individuals focus on and persist in the attainment of goals, which are both critical components to academic success (Ursache, Blair, & Raver, 2012). These skills are frequently described as the “air traffic control system of the brain,” where thoughts and impulses traveling throughout the brain are sorted and processed (Tough, 2016). There are three related yet distinct components that constitute executive function: (1) working memory, or the ability to hold and manipulate information in your mind; (2) cognitive flexibility, or the ability to shift your attention and perspectives; and (3) inhibitory control, or the ability to remain focused on tasks when distractions are present (Diamond & Lee, 2011).
Executive function does not develop automatically—its development depends on the quality of children’s environments, especially in early childhood (Blair, 2002; Diamond & Lee, 2011). Toxic stress in childhood impairs brain development and thus the development of executive function. Conversely, rich and stimulating environments that provide children with “scaffolding” necessary to practice executive function skills can help promote their development (Blair, 2002). For example, establishing routines and structures in children’s lives promotes these skills, ranging from parents engaging in discussions about handling disappointment to teachers’ procedures for having students line up to go to lunch.
Scholars of executive function see these skills as the building blocks for a range of higher-order concepts, such as self-regulation, attentional control, perseverance, and resilience (Morrison, Ponitz, & McClelland, 2010; Tough, 2013). Furthermore, some argue that executive function skills are particularly critical for early school adjustment—where students who are able to quickly adjust to school and regulate themselves creates a virtuous cycle wherein positive student-teacher relations develop (Blair & Diamond, 2008). For these reasons, this brief provides the first evidence on racial and socioeconomic gaps in executive function skills among a nationally representative sample of kindergartners as they proceed through early elementary school.
Methods
A detailed description of the data source, measures, and analytic approach is presented in the Technical Appendix. To summarize, the analysis draws on data from the Early Childhood Longitudinal Study, Kindergarten Class of 2010–11 (ECLS-K:2011) to examine racial and socioeconomic status–based gaps in executive function skills of early elementary school students. Two measures of executive function, the Numbers Reversed task and the Dimensional Change Card Sort (DCCS), captured student’s working memory and cognitive flexibility skills, respectively. Measures of math and reading achievement were also included for comparison of the magnitude of gaps. Indicator variables for racial group membership and socioeconomic status quintile were used as independent variables.
Standardized outcome measures were modeled using ordinary least squares (OLS) regression. Each dependent variable (Numbers Reversed, DCCS, math, and reading) was first regressed on either (1) indicators of race or (2) indicators of socioeconomic status in the fall of kindergarten and the spring of kindergarten, first, and second grades. Second, models for each outcome and assessment wave were estimated that include indicators of race and socioeconomic status together.
Results
Table 1 presents the regression results for the raw racial and socioeconomic gaps. In terms of race, students who are Black or Hispanic enter kindergarten with significantly lower working memory and cognitive flexibility skills than White students. For example, on the Numbers Reversed task, Hispanic students enter kindergarten performing 0.59 standard deviations lower, on average, than their White peers. These gaps are generally smaller than those for math and reading achievement, except for Black children’s reading achievement at kindergarten entry. Additionally, gaps between Asian students and White students are either small or insignificant in terms of executive function skills but quite large for academic achievement, with Asian students performing 0.21 and 0.30 standard deviations higher, on average, than their White peers.
Coefficients and Standard Errors for Racial and Socioeconomic Gaps in Executive Function and Achievement Outcomes
Note. All estimates are weighted to adjust for the ECLS-K:2011’s complex survey design. Standard errors are presented in parentheses below each coefficient. Reference category for race is White. Reference category for SES quintile is the first quintile. DCCS= Dimensional Change Card Sort; SES = socioeconomic status; ECLS-K:2011 = Early Childhood Longitudinal Study, Kindergarten Class of 2010–11.
p < .05.
Racial gaps in working memory and cognitive flexibility generally narrow more than gaps in academic achievement, especially for Hispanic students, between kindergarten entry and the end of second grade. For example, the gap between Hispanic students and White students on the Numbers Reversed task was more than halved between the time points, dropping from 0.59 to 0.27 standard deviations. This is in contrast to the measures of academic achievement, where the gap between Hispanic and White students marginally narrowed in math from 0.64 to 0.54 standard deviations and remained stagnant in reading at 0.50 standard deviations at kindergarten entry and the end of second grade.
Turning to socioeconomic status, the analysis reveals large gaps in working memory and cognitive flexibility skills at school entry. For example, students in the top socioeconomic status quintile score 1.01 standard deviations higher, on average, than their peers from the lowest socioeconomic status quintile on the Numbers Reversed task. As was the case with race, gaps generally decrease over time, but the decrease was much more pronounced for working memory than for cognitive flexibility. Further, at kindergarten entry, the magnitude of socioeconomic status gaps is similar between the measure of working memory and measures of academic achievement. That said, by the end of second grade, socioeconomic status–based gaps remain stable in mathematics achievement, increase in reading, and universally decrease in terms of working memory. Socioeconomic gaps for the DCCS task are generally lower than the other three measures.
Table 2 presents the regression results for models that include both race and socioeconomic status at the same time. The purpose of these models is to begin to disentangle the relative magnitude of gaps while holding either race or socioeconomic status constant. The overall magnitude of gaps, either for race of socioeconomic status, nearly uniformly diminish. In general, the magnitude of the racial gaps in executive function diminish more than the magnitude of socioeconomic gaps. For example, the average executive function coefficient for race decreased by 39% while the average executive function coefficient for socioeconomic status decreased by 21%. That said, after controlling for socioeconomic status, racial gaps remain both statistically and practically significant, though the magnitude of the coefficients for race are generally lower than the coefficients for socioeconomic status. Comparing these results to the academic achievement outcomes, the average decrease in the magnitude of the race coefficients is larger for math and reading and smaller for the socioeconomic status coefficients.
Coefficients and Standard Errors for Racial and Socioeconomic Gaps in Executive Function and Achievement Outcomes, Holding Constant Race and SES
Note. Presents models that include both race indicators and SES quintile indicators contemporaneously. All estimates are weighted to adjust for the ECLS-K:2011’s complex survey design. Standard errors are presented in parentheses below each coefficient. Reference category for race is White. Reference category for SES quintile is the first quintile. DCCS= Dimensional Change Card Sort; SES = socioeconomic status; ECLS-K:2011 = Early Childhood Longitudinal Study, Kindergarten Class of 2010–11.
p < .05.
Discussion and Conclusions
The purpose of this brief was to provide nationally representative evidence of racial and socioeconomic gaps in executive function skills in early elementary school using newly released data from the ECLS-K:2011. Consistent with previous analyses focusing on gaps in academic achievement (e.g., Reardon, 2011), the present analysis reveals large and significant gaps between racial groups and socioeconomic status quintiles. Further, the socioeconomic status–based gaps are larger in magnitude than the race-based gaps. However, there is some good news: The gaps in children’s executive function skills appear to narrow more than academic achievement as they progress through early elementary school, though they still do not close. While the present analysis does not reveal specific answers for why executive function gaps narrow in early elementary school, recent research indicates that schools may support the promotion of executive function skills (Little, 2016). It is possible that the scaffolding and routines introduced in school help to support children who may not have received such supports at home, thus narrowing the observed gaps. Given the critical importance of executive function skills for early school success and a host of later schooling outcomes (Blair & Diamond, 2008; Ursache et al., 2012), these results show that much work needs to be done to ensure that children, regardless of race or family background, enter school on a level playing field with their White, Asian, or more affluent peers.
There are a number of limitations to consider with the present analysis. First, there is a prominent critique that educational researchers focus too much on “gaps” between students of different racial or socioeconomic statuses. Popularized in her 2006 AERA Presidential Address, Gloria Ladson-Billings argues that our focus should shift from the achievement gap to the education debt. She argues that a focus on gaps “moves us toward short-term solutions that are unlikely to address the long-term underlying problem,” similar to government focusing on fiscal deficits as opposed to accumulated debt (Ladson-Billings, 2006, p. 4). While the purpose of this brief was to present new data on an outcome that has never been collected in a nationally representative fashion, this critique should stimulate researchers to interrogate the underlying causes of the gaps observed here and the ways in which they may be addressed.
Second, the analysis primarily focused on the unconditional differences based on the categories of race and socioeconomic status. These estimates are observational and do not begin to address the causal mechanisms through which these gaps manifest. Third, the ECLS-K:2011 only incudes two measures of executive function, working memory and cognitive flexibility, which leaves out a third component that many scholars of executive function agree exists—inhibitory control (Diamond & Lee, 2011). Fourth, there is a debate over the extent to which direct assessment measures of executive function are valid measures of the ways in which these skills manifest themselves in practice. For example, research has shown that the correlation between direct executive function measures and teacher ratings of classroom self-regulation are only moderately correlated (Morrison et al., 2010). Thus, it is important to consider that while these measures capture the discrete cognitive processes of executive function, there is concern that they may not adequately capture what Morrison et al. (2010) call “executive function in context” (p. 7). The hope is that this brief will help stimulate conversations and future research in the area of executive function skills in early elementary school and the ways in which racial and socioeconomic gaps in these skills can be ameliorated.