A growing body of evidence indicates that exposure to air pollution affects cognitive performance; however, few studies have assessed this in the context of repeated measures within a large group of individuals or in a population with a large age range. In this study, we evaluated the associations between long-term exposure to fine particulate matter (PM) and ozone (O) in large cohort of adults aged 18-90 years. The study cohort included 29,091 Lumosity users in the contiguous US who completed 20 repetitions of the Lost in Migration game between 2017 and 2018. Game scores reflect the ability to filter information and avoid distracting information. Long-term air pollution data included ambient PM and O averaged for the 365-day period before each gameplay date. Generalized linear models were used to examine the associations between long-term PM and O and game score percentile. Co-pollutant models were adjusted for meteorology, time trend, age, gender, device, education, local socioeconomic factors, and urbanicity. Results represent the change in attention game score percentile per 1 μg/m increase in PM or 0.01 ppm increase in O. In the entire cohort, a -0.10 (95% CI: -0.16, -0.04) change in score percentile was associated with PM, while no significant association was observed with O. Modification of these associations by age was observed for both PM and O, with stronger associations observed in younger users. In users aged 18-29, a -0.25 (-0.45, -0.05) change in score percentile was associated with PM, while no associations were observed in other age groups. With O, there was a -2.92 (-4.63, -1.19) and -2.81 (-4.29, -1.25) change in score percentile for users aged 18-29 and 30-39, respectively. We observed that elevated long-term PM and O were associated with decreased focus scores in young adults, but follow-up research is necessary to further illuminate these associations.