A functional magnetic resonance imaging study of auditory mismatch in schizophrenia

Objective: Previous research has noted functional and structural temporal l obe abnormalities in schizophrenia that relate to symptoms such as auditory hallucinations and thought disorder. The goal of the study was to determin e whether the functional abnormalities are present in schizophrenia at earl y stages of auditory processing. Method: Functional magnetic resonance imaging activity was examined during the presentation of the mismatch stimuli, which are deviant tones embedded in a series of standard tones. The mismatch stimuli are used to elicit the mismatch negativity, an early auditory event-related potential. Ten patient s with schizophrenia and 10 comparison subjects were presented the mismatch stimuli condition and a control condition in which only one tone was prese nted repeatedly. Results: The superior temporal gyrus showed the most prevalent and consiste nt activation. The superior temporal gy rus showed less activation in the s chizophrenic subjects than in the comparison subjects only during the misma tch stimuli condition. Conclusions: This result is consistent with those of mismatch negativity ev ent-related potential studies and suggests that early auditory processing i s abnormal in chronic schizophrenia.