Jumping to conclusions bias in early psychosis: Relationships with symptom dimensions, neurocognition and social cognition

Cognitive biases, such as "jumping to conclusions" (JTC), play an important role in the development and maintenance of delusions in psychotic disorders. However, their associations with symptom dimensions in early psychosis (EP) remain unclear. We aimed to investigate whether patients with EP who tend to jump to conclusions differ from those who do not in terms of symptom dimensions. We also examined relationships among symptoms, JTC, neurocognition, facial emotion recognition (FER) and theory of mind (ToM). Seventy-five patients attending an EP intervention programme were assessed using the Positive and Negative Syndrome Scale and cognitive tasks. A multivariate analysis of covariance (MANCOVA) and a permutation-based nonparametric MANOVA (PERMANOVA), adjusted for demographic factors, were conducted to examine differences between patients with and without JTC bias across symptom dimensions and depressive symptoms. Bivariate correlations were performed to explore associations between variables. A significant multivariate effect was found (Pillai's trace = 0.291; F_{5, 65} = 5.330; p < .001) with large effect sizes. JTC patients scored higher than non-JTC patients on all symptom dimensions. At the symptom level, JTC bias was significantly correlated with delusions and hallucinations, as well as with ToM and FER. Concluding, patients with EP who jump to conclusions exhibit a distinct symptom dimension pattern characterised by more severe symptoms. Furthermore, ToM and FER are related to JTC and symptom dimensions. These findings are clinically relevant, as psychological interventions targeting cognitive biases and social cognition appear to be effective in improving psychotic symptoms. Further studies are needed to replicate these findings.