Reduced attention-driven auditory sensitivity in hallucination-prone individuals.

BACKGROUND Evidence suggests that auditory hallucinations may result from abnormally enhanced auditory sensitivity. AIMS To investigate whether there is an auditory processing bias in healthy individuals who are prone to experiencing auditory hallucinations. METHOD Two hundred healthy volunteers performed a temporal order judgement task in which they determined whether an auditory or a visual stimulus came first under conditions of directed attention ('attend-auditory' and 'attend-visual' conditions). The Launay-Slade Hallucination Scale was used to divide the sample into high and low hallucination-proneness groups. RESULTS The high hallucination-proneness group exhibited a reduced sensitivity to auditory stimuli under the attend-auditory condition. By contrast, attention-directed visual sensitivity did not differ significantly between groups. CONCLUSIONS Healthy individuals prone to hallucinatory experiences may possess a bias in attention towards internal auditory stimuli at the expense of external sounds. Interventions involving the redistribution of attentional resources would have therapeutic benefit in patients experiencing auditory hallucinations.