Cognitive biases and auditory verbal hallucinations in healthy and clinical individuals.

BACKGROUND: Several cognitive biases are related to psychotic symptoms, including auditory verbal hallucinations (AVH). It remains unclear whether these biases differ in voice-hearers with and without a 'need-for-care'.
METHOD: A total of 72 healthy controls, 72 healthy voice-hearers and 72 clinical voice-hearers were compared on the Cognitive Biases Questionnaire for psychosis (CBQp), which assesses 'intentionalizing', 'jumping to conclusions', 'catastrophizing', 'dichotomous thinking' and 'emotional reasoning' in vignettes characterized by two themes, 'threatening events' and 'anomalous perceptions'.
RESULTS: Healthy voice-hearers scored intermediately on total CBQp between the control and clinical groups, differing significantly from both. However, on four out of five biases the scores of the healthy voice-hearers were comparable with those of the healthy controls. The only exception was 'emotional reasoning', on which their scores were comparable with the clinical group. Healthy voice-hearers demonstrated fewer biases than the psychotic patients on the 'threatening events', but not the 'anomalous perceptions', vignettes. CBQp scores were related to both cognitive and emotional, but not physical, characteristics of voices.
CONCLUSIONS: Most cognitive biases prevalent in clinical voice-hearers, particularly with threatening events themes, are absent in healthy voice-hearers, apart from emotional reasoning which may be specifically related to the vulnerability to develop AVH. The association between biases and both beliefs about voices and distress/emotional valence is consistent with the close links between emotions and psychotic phenomena identified by cognitive models of psychosis. The absence of reasoning biases might prevent the formation of threatening appraisals about anomalous experiences, thereby reducing the likelihood of distress and 'need for care'.