The unity and diversity of executive functions across adulthood in a diverse Brazilian sample with varying educational attainment

Executive functions (EFs) are a set of cognitive abilities associated with many social and clinical outcomes which are believed to be sensitive to culture, age and educational attainment. Yet, theoretical models of EF and tasks used to measure them were developed mainly for highly educated young adults from developed countries. Here we assessed EFs in a diverse cohort from a rural town in Brazil (Baependi Heart Study: N=1253; 753 females), in which age (18-88 year) and schooling (0-23 years) varied widely. Based on a popular theoretical model of EF (the unity diversity EF framework), which describes the pattern of inter-associations of three specific types of EFs (inhibitions, shifting and updating), we developed a short, nonautomated, open-access EF test battery adapted for use in samples with varying schooling and age that included EF indicators obtained from three tasks (Plus-Minus, Trail Making and Random Number Generation tasks). Using Confirmatory Factor Analyses we found a good fitting three-correlated factor solution confirming the fractionation and inter-association of the three EF domains that was invariant (except for one of eight indicators) to age, schooling and sex. More years of schooling was related to higher latent traits in all domains, older age to worse shifting and women scored lower in latent shifting and inhibition. We conclude that the unity-diversity EF framework can be determined across adulthood in diverse samples with tasks adapted for these populations, allowing the theory-oriented investigation of sociocultural and demographic factors that influence EFs.