The relationship between cognitive biases and psychological dimensions of delusions: The importance of jumping to conclusions

•The linkage between delusions' dimensions and cognitive biases was investigated controlling for hallucinations.•Jumping to conclusions was related to emotional and cognitive dimensions of delusions controlling for hallucinations.•Dichotomous thinking and intentionalizing were related to emotional dimensions of hallucinations controlling for delusions.•Jumping to conclusions seem to be a specific cognitive bias for both emotional and cognitive dimensions of delusions.

Background and objectivesCognitive biases play a role in the development and maintenance of delusions. However, delusions are multidimensional (i.e., emotional and cognitive facets) and often co-occur with auditory hallucinations. Therefore, further refinement of the precise relationship between cognitive biases, delusions, and hallucinatory experiences is warranted.MethodsA total sample of 167 patients with schizophrenia spectrum disorders was split into two groups consisting of patients with active delusions (n = 127) and active hallucinations (n = 92). All patients were assessed for delusions and hallucinations using the semi-structured psychotic symptom rating scales (PSYRATS), which assesses the emotional (i.e., distress) and cognitive (i.e., conviction, preoccupation) dimensions of these symptoms. Cognitive biases were assessed with the Cognitive Biases Questionnaire for Psychosis (CBQp) self-report questionnaire (assessing jumping to conclusions, intentionalising, catastrophising, emotional reasoning, and dichotomous thinking biases). Multiple stepwise regressions were performed to investigate the relationship between delusions and cognitive biases, while controlling for auditory hallucinations (and vice-versa).ResultsThe only cognitive bias to significantly predict delusions after controlling for the severity of auditory hallucinations was the jumping to conclusions (JTC) bias (predicted both emotional and cognitive dimensions). Only the emotional dimension of auditory hallucinations was predicted by the intentionalising and dichotomous thinking biases, after delusional severity was controlled for.LimitationsThe cross-sectional design precludes causal inferences. Only positive psychotic symptoms were assessed and no wider psychopathology assessment was utilised (e.g., negative symptoms, anxiety, depression).ConclusionsThe jumping to conclusions bias is associated with both delusional conviction and emotional distress.