Effective connectivity of implicit emotion processing in adolescent psychiatric inpatients: Dynamic causal modeling across bipolar disorder and other psychopathologies.

BACKGROUND: Pediatric bipolar disorder(BD) is difficult to distinguish from other psychiatric disorders, a challenge which can result in delayed or incorrect interventions. Understanding objective neural markers reflecting a dysfunction in recognizing implicit facial emotional social cues may aid in early diagnosis in BD. METHODS: We used neuroimaging and a dynamic causal modeling(DCM) framework to identify effective connectivity(EC) measures differentiating a rarified sample of inpatient adolescents with BD from other inpatient psychopathology(OP), and healthy adolescents(HC) during an emotional faces processing task. We hypothesized that EC patterns would differ between groups, reflecting disorder-specific alterations in neural networks involved in emotion processing, and that within inpatient groups, the observed EC patterns would be associated with the severity of clinical mood symptoms. DCM was used to analyze EC in BD(n = 29), OP(n = 39), and HC(n = 21); mean age 15.26 years, 60 females. Participants performed a dynamic emotional faces paradigm with four conditions: anger, fear, sadness, and happiness. Group-level Parametric Empirical Bayes(PEB) analyses examined EC patterns, followed by correlation analyses of relationships between EC and clinical symptom severity. RESULTS: Analysis revealed divergent and convergent EC patterns across groups and conditions. EC in BD and OP was associated with self-reported clinical symptoms severity of current mania, current depression, positive and negative affect. CONCLUSIONS: Our findings suggest that altered EC patterns between regions supporting social emotion processing and executive control may underlie difficulties in implicit facial emotion processing. These dysfunctional EC patterns may contribute to social impairments in pediatric BD. Understanding these neural connectivity alterations could inform targeted interventions to mitigate the adverse effects of BD on social functioning in youth.