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Introduction to the Special Issue on Understanding Neurobiological Implication of Maltreatment: From Preschool to Emerging Adulthood

Evidence on the psychological and behavioral impacts of child maltreatment is vast. More recently, empirical efforts are directed to unravel the neurobiological process that underlies the effect of adverse rearing environments on human development across the life span (Cicchetti & Toth, 2005; Gilbert et al., 2009). Such biopsychosocial models of human behavior are seeded in the concept of biological embedding, the notion that early experiences alter underlying biological systems to produce stable, long-lasting differences, ultimately influencing trajectories of health, behavior, and/or learning (Hertzman, 2000). Over the last decade, evidence for credible candidate mechanisms has emerged (Hertzman & Boyce, 2010; Rutter, 2012). Accordingly, we are now well positioned to investigate when, and by what means, child maltreatment may influence key biological systems. This special issue includes articles with empirical evidence on a range of biological mechanisms linking child maltreatment to various outcomes, spanning from preschool to emerging adulthood. Below, we provide an overview of some key concepts framing research on the biological impact of child maltreatment primarily utilizing a developmental psychopathology framework (Cicchetti & Toth, 2009). Within these concepts, we highlight the nine papers comprising this special issue, including eight empirical papers utilizing multiple methodologies and exploring diverse outcomes as well as one review paper (McCrory, Ogle, Gerin, & Viding, 2019) highlighting compromised social functioning as a key mechanism linking childhood maltreatment to subsequent psychopathology. We hope that this issue stimulates an expansion of interdisciplinary research on underlying biological systems given that mechanisms mediating enduring vulnerabilities in maltreated individuals remain relatively scarce. Furthermore, recognition of early biological markers underlying pathogenic effects of child maltreatment is important to inform both public health initiatives and clinical practice. A key tenet of developmental psychopathology is the concept of multifinality. Multifinality suggests that individuals exposed to the same adverse event or risk factor, such as child maltreatment, may have divergent patterns of adaptation and maladaptation (Cicchetti & Rogosch, 1996). The likelihood of a specific outcome is dependent on the complex interaction of multiple factors and processes related to individual characteristics, experiences, timing, and the developmental history of the individual (Sroufe, 1990). This concept is highly relevant when attempting to understand why some individuals exposed to child maltreatment experience maladaptive outcomes, while others do not, and how biological factors may play a role in these divergent pathways. The papers in this special issue represent diverse methodological approaches to studying neurobiological pathways linking child maltreatment to adjustment and psychopathology outcome across the life span. Several papers involve longitudinal data to delineate patterns over time, leading to various outcomes including alcohol use (DeBellis et al., 2019; Oshri et al., 2019), shyness (Poole, MacMillan, & Schmidt, 2018), trait impulsivity (Hallowell et al., 2019), internalizing and externalizing problems (Demers et al., 2019; Oshri et al., 2019; Peverill, Sheridan, Busso, & McLaughlin, 2019), and adaptive functioning (Demers et al., 2019). Another important aspect in the investigation of the neurobiology of child maltreatment is the concept of multilevel analysis. While much of the research to date has focused primarily on psychosocial outcomes, in the past two decades, empirical studies have incorporated multilevel