Theta rhythm increases in left superior temporal cortex during auditory hallucinations in schizophrenia: a case report

Auditory hallucinations (AH), the perception of sounds and voices in the ab sence of external stimuli, remain a serious problem for a large subgroup of patients with schizophrenia. Functional imaging of brain activity associat ed with AH is difficult, since the target event is involuntary and its timi ng cannot be predicted. Prior efforts to image the patterns of cortical act ivity during AH have yielded conflicting results. In this study, MEG was us ed to directly image the brain electrophysiological events associated with AH in schizophrenia. We observed an increase in theta rhythm, as sporadic b ursts, in the left superior temporal area during the AH states, whereas the re was steady theta band activity in the resting state. The present finding suggests strong association of the left superior temporal cortex with the experience of AH in this patient. This is consistent with the hypothesis th at AH arises from areas of auditory cortex subserving receptive language pr ocessing. NeuroReport 11:3283-3287 (C) 2000 Lippincott Williams & Wilkins.