A Gap in Executive Function Correlates with Poverty

By now, we should all be acquainted with academic achievement gaps that correlate with socioeconomic status. Children from poor families start kindergarten behind their wealthier peers by as much as one standard deviation in both reading and math. A recent analysis of nationwide data on young children in the United States reveals that indigent children are also scoring lower in assessments that measure working memory and the ability to switch gears. These mental functions, the ability to hold onto and work with information, and the flexibility to shift one's attention are part of what we call executive functions of the brain. Children immensely develop executive function skills during ages 3-5. The Center on the Developing Child at Harvard University in its research brief on executive function skills takes note of the following: "Adverse conditions such as abuse, neglect, community violence, and persistent poverty can disrupt brain architecture and place children at a disadvantage with regard to the development of their executive function skills."

Tests measuring different forms of executive function skills indicate that they begin to develop shortly after birth, with ages 3 to 5 a window of opportunity for dramatic growth in these skills. Development continues throughout adolescence and early adulthood.
(Copied from Center on the Developing Child (2012). Executive Function (InBrief). Retrieved from www.developingchild.harvard.edu)
Executive function skills are obviously important factors in learning. In addition, a child whose executive function is delayed may appear as belligerent or inattentive, and therefore may be easily labeled as a "troublemaker". Gaps in executive function skills due to poverty are therefore important to recognize so that schools are better able to respond to the needs of these students.

In the nationwide study, working memory has been assessed by the Numbers Reversed task, during which a child is given a set of numbers and is then asked to give back those numbers but in a reversed order. Mental flexibility, on the other hand, is measured by Dimensional Change Card Sort (DCCS), described in the following figure:

Above copied from
The Dimensional Change Card Sort (DCCS): a method of assessing executive function in children
Philip David Zelazo
Nature Protocols 1, 297 - 301 (2006)
Executive function skills actually include self-control, but is not measured in the study. However, it has already been suggested that poverty also adversely affects a person's self-control. The gaps in both working memory and mental flexibility at the beginning of kindergarten are actually substantial (measured in terms of standard deviation):

Above graphs based on
Racial and Socioeconomic Gaps in Executive Function Skills in Early Elementary School. Michael Little. Educational Researcher Vol 46, Issue 2, pp. 103 - 109. First published date: March-09-2017
The above gaps can be compared to academic achievement gaps. Gaps in mental flexibility is about half of the gaps in reading and math, while gaps in working memory are almost the same as those in reading and math.

Above graphs based on
Racial and Socioeconomic Gaps in Executive Function Skills in Early Elementary School. Michael Little. Educational Researcher Vol 46, Issue 2, pp. 103 - 109. First published date: March-09-2017
What is encouraging is that while academic gaps persist throughout elementary school, gaps in executive function skills narrow such that by second grade, the gap in working memory has already been halved. It is therefore very important to support a child's growing executive function skills as early as possible. Research has shown that a safe and less stressful environment is important. Children learn from adults and developing executive function skills is no exception. Children need models they could follow. Mental development not only requires proper nutrition but also physical exercise. Recess and physical education are crucial periods in kindergarten and elementary schools. Not only do these periods provide physical activity but also opportunities for exploration, creativity and social interactions. Without addressing gaps in executive function skills, tackling gaps in both math and reading can easily become exercises in futility.