Disentangling the effects of smartphone screen time, checking frequency, and problematic use on executive function: A structural equation modelling analysis

The pervasiveness of smartphone engagement among young adults has attracted growing interest regarding its impact on cognitive processes. However, research on the relation between smartphone use and executive function (EF)—a set of adaptive, goal-directed control processes—remains inconclusive due to imprecise estimation of EF dimensions and inconsistent operationalisation of smartphone use in past studies. Therefore, we examined how two indices of smartphone use—screen time and checking frequency—would predict EF (common EF, shifting-specific-, and working-memory-specific components), using a latent-variable approach based on a comprehensive battery of EF tasks. We also examined the moderating role of problematic smartphone use in the link between smartphone use and EF components. We found that screen time positively predicted working-memory-specific and shifting-specific abilities, whereas frequent checking was associated with enhanced shifting-specific, but poorer common EF, abilities. Importantly, problematic smartphone use moderated the relation between checking frequency and common EF. Overall, our findings demonstrate that different indices of smartphone use asymmetrically predict EF facets, thereby highlighting the construct distinctiveness of the various markers of smartphone engagement. Our findings imply that checking frequency and problematic use, rather than screen time, are the most promising targets for interventions that aim to circumvent cognitive impairments by curtailing smartphone use, especially in educational settings.