Critically evaluate research in two areas of developmental psychology research

1. Introduction

Adverse childhood experiences (ACEs) — such as abuse, neglect, household dysfunction, or exposure to violence — have a profound influence on children’s social, emotional, and cognitive development. A growing body of research links ACEs to an increased risk of developing disruptive behaviour disorders (DBDs), such as oppositional defiant disorder (ODD) and conduct disorder (CD). Both ACEs and DBDs are of major concern in developmental psychology because they can have lifelong effects on mental health, education, and relationships.

This review critically evaluates research from two main areas:

1. Impact of ACEs on child and adolescent development

2. Aetiology and mechanisms underlying disruptive behaviour disorders

The discussion highlights theoretical overlaps — in particular, how early adversity may shape neurobiological systems, cognitive functioning, and socio-emotional regulation in ways that increase vulnerability to DBDs. The review will argue that integrating research from these two areas can improve our understanding of child psychopathology and inform targeted prevention strategies. Finally, a brief research proposal will be presented to address key gaps identified.

2. Literature Review and Critical Evaluation

2.1 Area 1: Adverse Childhood Experiences (ACEs) and Development

The original ACE study (Felitti et al., 1998) demonstrated a strong dose–response relationship between the number of ACEs and a range of negative health and behavioural outcomes in adulthood. Subsequent research (Hughes et al., 2017) has extended this to child and adolescent mental health, showing associations with emotional dysregulation, poor academic performance, and increased externalising behaviours.

Theoretical framework:

• Toxic stress model (Shonkoff et al., 2012) posits that chronic activation of the stress response disrupts brain development and stress regulation systems.

• Attachment theory (Bowlby, 1969) suggests that early adversity, particularly inconsistent or harmful caregiving, undermines secure attachment, influencing emotional control and interpersonal relationships.

Critical evaluation:

While there is consistent evidence linking ACEs to behavioural problems, much of it is correlational, limiting causal inference. Many studies rely on retrospective self-report measures, which can be subject to recall bias (Hardt & Rutter, 2004). Moreover, ACEs often co-occur with poverty, poor schooling, and community violence, making it difficult to isolate their specific effects (Evans et al., 2013). Longitudinal studies (e.g., Lansford et al., 2002) provide stronger evidence but still face challenges in accounting for unmeasured confounding variables such as genetic risk.