COMPUTATIONAL MODELS OF LATENT VULNERABILTIY AMONG CHILDREN AT RISK OF PSYCHOPATHOLOGY

The experience of maltreatment in childhood and adolescence has profound and enduring consequences for mental health. Individuals with histories of maltreatment have a significantly increased risk of concurrent and future internalizing and externalizing psychiatric disorders (Gilbert et al. 2009), with childhood adversities more broadly accounting for as much as 45% of the risk of childhood-onset psychiatric disorders and ~ 30% of adult and adolescent-onset disorders (Green et al. 2010; Kessler et al. 2010). When mental health problems do arise, they tend to be associated with an earlier onset of symptoms, greater comorbidity, and poorer responsiveness to traditional interventions such as CBT or antidepressants (Agnew-Blais et al., 2016; Nanni et al., 2012).
Despite this well-established association between early maltreatment exposure and the development of psychopathology, we know very little about how maltreatment embeds such long-term risk. As a consequence, public policy - specifically, resource allocation decisions for public services at the national and local authority level - is rendered unsupported by guiding principles for how funds should be best allocated in order to disrupt these (unknown) mechanisms. Although comparable statistics are not readily available for UK as a whole, data pertaining to Wales published in 2017 has shown that only 6% of children on the child protection register are classified as suffering from mental health problems. For children looked after by local authorities the proportion was 8%. These figures contrast sharply with estimates of the lifetime effects of early adversity. For example, in a study of predominantly middle-class American adults, 53% of subjects who had experienced severe levels of adversity met the lifetime criteria for major depressive disorder (MDD), and 23% met the full DSM-5 criteria for PTSD (Teicher et al., 2012).
This disparity between rates of early symptomology and the risk of later developing a psychiatric illness can, in part, be explained by evidence that maltreatment leads to measurable changes in both how different neurocognitive systems in the brain function, as well as alterations in neural architecture (Teicher & Samson 2016; Teicher et al. 2016). The theory of latent vulnerability postulates that these alterations can be understood in part as adaptations to early adverse or neglectful environments in line with the notion of experiential canalization (Blair & Raver 2012; McCrory & Viding 2015). While such adaptations are thought to confer short-term functional advantages in atypical early environments, they are believed to contribute to long term mental health vulnerability.
Over the course of my doctoral research, I will investigate the possibility that this vulnerability can in large part be understood in the context of impaired social functioning over the life course, which I will explore using a combination of task-based fMRI and computational modelling. Such a proposal is informed by the central role that effective social functioning plays in sustaining good mental health - both in helping us to successfully negotiate stress and life challenges, but also in cultivating and sustaining a network of supportive relationships that help mitigate the impact of stressors when they do arise.