The Power of Theory, Research Design, and Transdisciplinary Integration in Moving Psychopathology Forward

Abstract

While the past few decades have seen much work in psychopathology research that has yielded provocative insights, relatively little progress has been made in understanding the etiology of mental disorders. We contend that this is due to an overreliance on statistics and technology with insufficient attention to adequacy of experimental design, a lack of integration of data across various domains of research, and testing of theoretical models using relatively weak study designs. We provide a conceptual discussion of these issues and follow with a concrete demonstration of our proposed solution. Using two different disorders – depression and substance use – as examples, we illustrate how we can evaluate competing theories regarding their etiology by integrating information from various domains including latent variable models, neurobiology, and quasi-experimental data such as twin and adoption studies, rather than relying on any single methodology alone. More broadly, we discuss the extent to which such integrative thinking allows for inferences about the etiology of mental disorders, rather than focusing on descriptive correlates alone. Greater scientific insight will require stringent tests of competing theories and a deeper conceptual understanding of the advantages and pitfalls of methodologies and criteria we use in our studies.

Testing the effects of adolescent alcohol use on adult conflict-related theta dynamics

“…Several lines of research support as relevant causal factors both the potential neurotoxic effects of early alcohol exposure (Jacobus and Tapert, 2013) and the heritability of alcohol-related brain dysfunction (Iacono et al, 2008). Because of this, quasi-experimental research designs/methods, such as comparing members of twin pairs who differ in their degree of early alcohol exposure, are needed to permit stronger etiological inferences (Vaidyanathan et al, 2015). …”

Connecting psychopathology meta-structure and mechanisms.

“…Some of the differences might reflect variations in approaches to modeling (Edwards, 2010) or variation in statistical procedures (see Barrett, 2007;Vaidyanathan, Vrieze, & Iacono, 2015). But such discrepancies may have theoretical implications or be informative in other ways.…”

Moving Psychopathology Forward

“…In calling for risky tests, Vaidyanathan et al (this issue) assert the benefits of incorporating data from multiple domains, very much in line with the provisions of RDoC (Cuthbert & Insel, 2013). Vaidyanathan and colleagues illustrate this point by examining research on the startle blink reflex and the error-related negativity component of the event-related brain potential and their joint contribution in clarifying the neurobiology of depression.…”

“…Vaidyanathan et al (this issue) offer provocative proposals for the striking lack of progress, after decades of basic and clinical research, in understanding the etiology of psychopathology. They engage a number of prominent issues.…”

“…The critique of the psychopathology literature that Vaidyanathan et al (this issue) offer stands regardless of how one might view controversies about DSM V vs. RDoC, about categorical vs. dimensional concepts, or about the roles and relationships between psychological vs. biological phenomena in psychopathology. Vaidyanathan and colleagues press not just for clearly articulated theories but for strong tests of them.…”