Adolescence marks a pivotal developmental period that is characterized by socioemotional changes, heightened brain plasticity, and represents the peak onset time of mental disorders. Distinguishing between typical behavior and emotions within an individual and changes that are indicative of mental disorders requires a comprehensive understanding of youth psychopathology and appropriate diagnostic criteria. In the last few years, new approaches to capture the multifaceted nature and dimensionality of mental disorders have been proposed, including the so-called p-factor, the Hierarchical Taxonomy of Psychopathology (HiTOP), the Research Domain Criteria (RDoC), and network models of mental disorders (Borsboom, 2017; Caspi et al., 2014; Insel et al., 2010; Kotov et al., 2017). Moreover, emotion dysregulation has been described as a transdiagnostic marker of psychopathology (Aldao et al., 2010; Cludius et al., 2020; McLaughlin et al., 2011) and highlights the intertwined nature of psychopathology and emotion processing and regulation. Problems with emotion identification and regulation have been found in youth with mental disorders on the behavioral (Collin et al., 2013; McLaughlin et al., 2011; Simcock et al., 2020), but also the neural level (Padgaonkar et al., 2021; Stephanou et al., 2017). Functional connectivity patterns between the default (DN), frontoparietal (FP), and salience (SA) network play key roles in emotion processes and have been associated with psychopathology (Menon, 2011; Xia et al., 2018). Nevertheless, the association between youth psychopathology and functional connectivity in emotion-related neural networks remain poorly understood.
Particularly, youth whose parents struggle with mental health problems show an increased risk of psychopathology and emotion regulation difficulties (Garcia et al., 2024; McLaughlin et al., 2012; Schepman et al., 2011). Parents (as primary caregivers) play a crucial role in the emotional development of children (Morris et al., 2007, 2017), indicating that parental psychopathology may be a risk factor in relation to development of emotion regulation skills in the offspring. To identify markers of risk and potential targets for interventions, it is thus important to understand how parental psychopathology affects the development of emotion-related functional networks in youth.
In this thesis, I sought to understand the links between youth psychopathology, emotion processing and regulation, and their neural underpinnings. Moreover, I aimed to uncover how parental psychopathology affects youth’s emotion-related neural networks. To this end, I investigated different aspects of the associations between youth psychopathology and emotion-related networks across three studies. We used both task-based and resting-state functional connectivity from two large-scale developmental cohorts and different approaches to conceptualize youth psychopathology. Utilizing a range of advanced statistical methods allowed us to explore the relationship between youth psychopathology and emotion-related functional networks on various levels.
The first paper focused on how different dimensions of youth psychopathology relate to emotion identification and its underlying neural functional connectivity. We found emotion-specific associations between youth psychopathology and emotion identification on the behavioral and neural level, but the data indicated that these associations underlie independent processes.
In Paper II, we sought to test the associations between current parental psychopathology (internalizing, externalizing, and total problems) and youth’s functional connectivity in emotion regulation networks. Moreover, we tested if these network patterns mediated the relationship between parent psychopathology and future youth psychopathology. The analyses showed that parental psychopathology was linked to atypical functional connectivity patterns in emotion regulation networks, but did not support the hypothesis that these patterns mediate the positive association between parental and youth psychopathology.
Lastly, Paper III focused on a potential granularity of the associations between youth internalizing problems and functional connectivity patterns of the DN, FP, and SA. By integrating symptom and brain networks, we tested if internalizing problems and functional connectivity were associated on a symptom level. We found symptom-specific associations between internalizing problems and DN, FP, and SA connectivity. These results indicate that the heterogeneity of internalizing problems is partially reflected in functional connectivity patterns.
Taken together, these results show the complex interplay of youth psychopathology, emotion processing and regulation and functional connectivity. In order to properly understand their interaction, it is necessary to study the granularity of these associations. I therefore elucidate aspects of this granularity that show promise for clinical utility and should be further examined in future research. These include the distinction between capacity and tendency of emotion processes, the heterogeneity and co-occurrence of neurobiological measures in mental disorders, and the potential of parent-focused interventions to improve youth psychopathology. Given the methodological limitations within the field, I address proposals to improve research on youth psychopathology and emotion-related functional connectivity.