This study examines cognitive reserve theory by investigating the relationship between education and cognitive performance across developed and developing countries. Using numeracy and verbal fluency measures, it finds that higher education consistently improves cognition. However, cognitive performance is largely similar across countries once education level is considered, challenging assumptions about educational quality differences.

Learning a new language, even later in life, can boost attention within a single week and support long-term cognitive resilience. Intensive language learners outperform peers in non-language courses, with benefits spanning ages 18–78. Practising five hours weekly maintains gains, offering a promising, accessible strategy for stroke recovery and dementia delay.