Memory is not just a mental slideshow of days past. The ability to retain information and use it to make decisions is critical to accomplishing almost any task. This “working memory” develops as children grow, but some kids have better working memories than others. Research has shown that differences in socioeconomic status (SES) are a factor in these disparities, and may help explain differences in school performance.

A longitudinal study led by Penn researchers set out to better understand the factors that influence how working memory develops as children pass through adolescence.

The study was conducted by former Penn Ph.D. student Daniel Hackman and Professor Martha Farah, both of the Department of Psychology in Penn Arts & Sciences, in conjunction with researchers at the Children’s Hospital of Philadelphia and the Annenberg Public Policy Center.

“We wondered how the socioeconomic disparities seen in younger children’s working memory would change with further development,” Farah says. “Some researchers believed that the ongoing effects of living in a more or less deprived household would widen the gap over time; others thought that the lower SES kids might eventually catch up with their more privileged counterparts. Instead, we found that the disparities hold steady.”

Without improved conditions or helpful interventions, the working memory gap persists through adolescence.

Hackman, now a postdoctoral scholar at the University of Pittsburgh, says that understanding the development of disparities in working memory has implications for education.

“Persistent disparities are a potential source of differences in academic achievement as students age, and as the demands of both school work and the social environment increase,” he says.

The researchers studied a diverse group of more than 300 10- to 13-year-olds from urban public and parochial schools in order to determine the rate of change in working memory in relation to different measures of socioeconomic status.

Each child completed a number of working memory-related tasks across a four-year period. The researchers gathered information on how many years of education the parents of each child had completed, as well as information on neighborhood characteristics, such as the number of people in a child’s neighborhood who were unemployed, receiving public assistance, or living below the poverty line.

Farah, Hackman, and colleagues found associations between parental education level and working memory performance, but no correlation with neighborhood characteristics. 

The study suggests that working memory disparities seen in adolescence and adulthood begin in childhood, and schooling does not close the gap for children ages 10 and older. Generally, children whose parents had fewer years of education don’t catch up or fall further behind by the end of adolescence, when working memory performance reaches mature levels.

Be that as it may, the findings of this study do not suggest that working memory cannot be improved. Rather, interventions may help close the gap.

“The fact that parents’ education predicts working memory suggests that parenting practices and home environments may be important for this aspect of cognitive development,” Hackman says.