Investigating the development of executive functions and their relationship with educational attainment during adolescence: a study of inhibition, shifting and working memory

Background Research regarding the development of executive functions (EFs) and their association with educational attainment has disproportionately focused on younger ages, mainly pre-schoolers and primary school aged children. Conversely, the period of adolescence and specifically the later stages thereof have been largely overlooked, despite indications suggesting that particular aspects of EFs continue developing throughout adolescence and into young adulthood. Researching EFs during the latter part of adolescence might be particularly informative considering the increasing academic demands that adolescents encounter at school during these ages. In the final years of secondary school, adolescents are called to make critical academic and life decisions and work towards long-term goals (e.g., employment, further education), rendering EFs ever more potent during this period. Furthermore, in multifaceted subjects, such as science, in which attainment relies heavily on a variety of transferable skills, it may be through these skills that EFs affect adolescents’ attainment. Methods This thesis constitutes a unique contribution to the existing EF literature, in that it addresses questions regarding the development and relation of EFs to educational attainment in the previously overlooked period of late adolescence. Attainment in different disciplines was examined separately and, in the case of science, numeracy and non-verbal reasoning skills were examined as mediators of the relationship between EFs and attainment. A total of 347 adolescents, aged between 14 and 18 (i.e., years 3-5 of secondary school), were administered cognitive tasks that measured three EF components, namely inhibition, shifting and working memory, and completed paper-based assessments of their numeracy and non-verbal reasoning skills. Participants’ school grades/performance in national qualifications on a variety of subjects were considered as indicators of their educational attainment. Results The results showed that, within the large cross-sectional sample of 14-18 year olds considered, there were significant developmental changes in inhibition, but not shifting or working memory. Furthermore, there was strong evidence of associations between older adolescents’ EFs and their attainment in the curriculum areas of English, maths, science, social studies, modern languages and arts. Interestingly, the patterns of association among the three EF components and attainment differed as a function of age cohort. In a separate study, EFs were examined in relation to the oldest (fifth-year) adolescents’ performance in national qualifications for entry into university, but EFs were not found to have any significant effect beyond that of socioeconomic status. Finally, it was shown that the relationship between EFs and attainment in science was mediated by numeracy but not non-verbal reasoning skills. Conclusions This thesis showcases the significance of studying EFs in adolescence, with the results showing that certain aspects of EF continued maturing during the ages of 14- 18 and had an ongoing effect on adolescents’ educational attainment. These findings suggest that, even during the later stages of adolescence, EFs may constitute a useful target for educational interventions aimed at improving pupils’ attainment. In addition, this thesis highlights the important role of socioeconomic status as a determining factor of adolescents’ EFs and their educational attainment