Using interaction-based phenotyping to assess the behavioral and neural mechanisms of transdiagnostic social impairments in psychiatry

Excerpt

The idea that we should think of psychiatric disorders as “brain disorders” has been around for over 150 years. Over the decades, we have seen an impressive refinement of the methods and tools that have been put to use, but until today and in contrast to other branches of medicine such as oncology that have been highly successful in personalizing treatments we do not have any specific and reliable brain-based biomarkers available in psychiatry. This is all the more troubling as the global burden of mental health conditions is on the rise: In light of the dramatic numbers and a “monumental loss of human capabilities” resulting from mental ill health, the Lancet Commission on global mental health has recently spoken of a “global health crisis” and a “collective failure to respond to this”. Furthermore, the commission recognized the complex nature of psychiatric disorders and mental health by characterizing the latter as “the unique product of social and environmental influences interacting with genetic, neurodevelopmental and psychological processes and affecting biological pathways in the brain”. This characterization is reflected by the kind of research that has and is being conducted in psychiatry and the clinical neurosciences. Indeed, this research has focused on the genetic contributions to psychiatric disorders, but more recently also on the epigenetic factors, i.e., gene × environment interactions, which are relevant in shaping mental ill health [1]. In spite of the important advances and new insights that have been gained as a result of focusing more strongly on the interplay between social and biological factors [2], our understanding of how social factors influence the ‘social brain’ and how this could inform individual diagnosis and treatment is still limited. Furthermore, social impairments are ubiquitous across different psychiatric disorders, which (amongst other aspects) has led to the suggestion that we can describe them as disorders of social interaction, but also that we should focus on whether disordered social interactions are the result of disorder-general or disorder-specific mechanisms [3]. …