Wellbeing and cognition are coupled during development: A preregistered longitudinal study of 1136 children and adolescents

Wellbeing and cognition are linked in adulthood, but how the two domains interact during development is currently unclear. Using a complex systems approach, we preregistered and modelled the relationship between wellbeing and cognition in a prospective cohort of 1136 children, aged 6 - 7 up to 15 years. We found bidirectional interactions between wellbeing and cognition that unfold dynamically over time. Higher externalizing symptoms in childhood predicted fewer gains in planning over time (standardized estimate = - 0.14, p = .019), whereas higher childhood vocabulary predicted smaller increases in loneliness over time (standardized estimate = -0.34, p = < .001). These interactions were characterized by modifiable risk and resilience factors: Relationships to parents, friendship quality, socioeconomic status and puberty onset were all linked to both cognitive and wellbeing outcomes. As such, cognition and wellbeing are inextricably intertwined during development and may be malleable to social and biological factors.