The Impact of Adverse Childhood Experiences (ACEs) on Cognitive Control during Adolescence

Adverse childhood experiences (ACEs) have been linked to impairments in cognitive control, a set of mental processes essential for regulating thoughts, emotions, and behaviours. While prior research has established the negative impact of ACEs on cognitive control, the underlying neurocognitive mechanisms remain unclear. This doctoral thesis investigates the impact of ACEs on cognitive control, particularly during adolescence, a critical period of neurodevelopment, through three interconnected studies. Study One (Chapter Two) presents a systematic review and meta-analysis synthesising longitudinal evidence on the relationship between ACEs and cognitive control across the lifespan. Findings indicate consistent deficits in working memory, inhibitory control, and cognitive flexibility, with deprivation exerting a stronger negative impact on cognitive flexibility than other ACEs subtypes. Study Two (Chapter Three) extends these findings by adopting the data-driven approach using the Adolescent Brain and Cognitive Development (ABCD) Study. Factor analysis identified five ACEs dimensions—family hostility, school distress, financial deprivation, violence and abuse, and family mental health and substance use. These dimensions were differentially associated with specific cognitive control domains. Although pubertal status did not serve as a mediator in the longitudinal relationship between ACEs and cognitive control, findings highlight the bidirectional relationships between ACEs, pubertal development, and cognitive control. Study Three (Chapter Four) examines the neural mechanisms linking ACEs, cognitive control, and mental health. Using EEG recordings of error-related negativity (ERN) during an inhibitory control task, findings indicate that ACEs were associated with larger ERN amplitude and higher internalising symptoms, though no relationship was found with externalising symptoms. However, ERN did not mediate the relationship between ACEs and internalising symptoms, suggesting the need for further research with larger, more diverse samples. This thesis contributes to the growing body of research on the impact of ACEs on cognitive control and mental health by highlighting their multidimensional nature and complex interplay with neurodevelopmental factors. It underscores the importance of longitudinal designs, data-driven approaches, and neurophysiological methods in advancing our understanding of the long-term consequences of ACEs, ultimately informing future research and targeted interventions.