Executive functioning in low education contexts: evidence from a controlled clinical trial among illiterate adults

Abstract

AbstractBackgroundEducation level is a well established modifiable risk factor for dementia prevention. Aiming to improve cognitive reserve and reduce dementia risk in vulnerable populations in Brazil, we created a literacy training program targeting low educated and illiterate adults. In this study, we intend to analyze how executive functioning and cognitive heterogeneity may interfere in the program’s effectiveness.Method130 adults attending classes for adult education were screened and 108 met inclusion criteria. The group was divided into control (regular classes, n = 51) and intervention (regular classes + program targeting literacy training) (n = 57). In addition to answering clinical and education history questions, all the subjects underwent an extensive neuropsychological assessment at baseline and at follow up (after six months of intervention), measuring global cognition, executive functioning (EF), memory and language.Result77 subjects completed all the assessments at the end of the study. Mean age (years) was 59.0 (±9.17), mean education level (years) 2 (±2.18), 79.2% women and 89.6% Blacks. No significant differences were found between control and intervention groups improvement on reading abilities (reading accuracy of isolated words) at follow up. Considering abandonment reasons of formal education in childhood, subjects with childhood history of learning disability (CHLD) had less improvement on reading abilities at follow‐up. The CHLD group also showed poorer performance on a composite score of EF tasks at baseline (F = 3.814, p = 0.021). EF level at baseline correlated with reading abilities at baseline (Spearman’s rho = 0.659, p<0.001) and follow‐up (Spearman’s rho = 0.703, p<0.001).ConclusionBoth control and intervention groups showed improvement on reading abilities, regardless of specific literacy training. EF seems to have an impact on reading skills progress. Subjects with CHLD currently display poorer EF and show very little improvement of reading skills, which might indicate an undiagnosed neurodevelopmental disorder (e.g. ADHD, dyslexia, dyscalculia): an uncared condition still harming cognitive reserve improvement to this day. Thus, there is greater risk of developing dementia. Inclusive learning environments must also be considered for low educated populations.