Across boundaries Transdiagnostic and network approaches to psychopathology

Over the last couple of decades, an increasingly critical eye has been cast upon the current system of conceptualizing, researching, and treating psychopathology in which psychopathology is categorized into distinct categorical latent classes, which have become reified. With the increased recognition of the shortcomings of categorical classification, calls for a paradigm shift ensued and the transdiagnostic and network approaches emerged. The aim of this thesis was therefore to investigate the relationships between psychopathological symptoms, cognitive function, and other clinically-relevant factors (e.g., self-esteem, psychosocial functioning or existential concerns) through the use of the transdiagnostic and network approaches. As such, we examined research questions on 1) the relationship between cognitive function and psychopathology and neurobiology, respectively, 2) the interplay of various symptoms dimensions, and 3) the role of psychological and existential factors in psychopathology. Throughout this thesis, we also explored the use of the transdiagnostic and network approaches as methodologies for addressing these research questions and potentially advancing psychiatric research. We demonstrated that the transdiagnostic and network approaches can be useful and valuable for gaining insights into relationships between different dimensions of psychopathology and the necessity of going beyond the symptom-reduction model and addressing non-symptom factors. Altogether, the transdiagnostic and network approaches can continue drive the paradigm shift that departs from current perspectives of psychopathology as distinct categories as well as the common cause and symptom-reduction models, which may lead to a more comprehensive understanding of psychopathology and better inform research as well as clinical practice.