Lilja K. Jónsdóttir: Exploring the Self-Regulation Universe: Developmental Dynamics from Early Caregiving to Brain and Behaviour

Abstract

Childhood self-regulation, the ability to modulate behaviour, cognition, and emotion in service of adaptive behaviour and higher-order goals, is a robust predictor of important outcomes within childhood and beyond. Despite considerable research interest, the developmental pathways through which self-regulatory abilities emerge, interact, and relate to later outcomes are not fully understood. This thesis examines several of these pathways across three empirical studies, spanning multiple levels of analysis and developmental timepoints, with a focus on executive function (EF) and emotion regulation (ER). Study I investigated whether specific aspects of the early caregiving environment (maternal sensitivity and attachment security) predict self-regulation at age 6, and whether hot and cool EF in toddlerhood mediates these relationships. Contrary to hypotheses, no longitudinal associations were observed, raising important questions about whether the relationship between early caregiving and later self-regulation is more conditional, non-linear, or measurement-dependent than current models suggest. Study II examined whether inhibitory control in toddlerhood predicts internalizing and externalizing problems at age 9–10, and whether ER at age 6 mediates these pathways. No significant associations were found between early inhibitory control and later ER or internalizing or externalizing problems. However, general ER at age 6 predicted lower levels of both internalizing and externalizing problems, highlighting ER as a transdiagnostic, potentially modifiable factor in the development of childhood psychopathology. Study III examined developmental differences in choline concentration in the dorsal anterior cingulate cortex (dACC), a region implicated in error monitoring, action selection, and cognitive control, and its associations with cognitive control performance across children, adolescents, and adults. The association between dACC choline and cognitive control reversed direction across developmental stages (negative in children and positive in adults), suggesting that the neurobiological significance of this metabolite shifts fundamentally with development.Taken together, these findings reflect the conceptual and methodological complexity of studying self-regulation across development. While self-regulation remains a meaningful predictor of socioemotional outcomes, and neurobiological measures may offer meaningful insights into the development of cognitive control, transparent reporting of null findings reporting and continued refinement of theoretical and measurement approaches are necessary for advancing a cumulative science of self-regulation development.