Treating auditory hallucinations by transcranial magnetic stimulation: a randomized controlled cross-over trial.

Background: In a previous functional magnetic resonance imaging study, the authors succeeded in demonstrating the activation of Heschl's gyrus during auditory hallucinations (AH).

Objectives: This study aims to treat AH specifically by repetitive transcranial magnetic stimulation (rTMS).

Methods: 16 patients with AH were included in a randomized, cross-over, sham-controlled trial. 1 Hz rTMS was administered over the left and right temporo-parietal cortex and sham position, respectively, on 5 consecutive days; 900 stimuli each, strength 100% of motor threshold. Using the Psychotic Symptom Rating Scales (PSYRATS), the hallucinations during the stimulation periods and 4-week follow-ups were quantified. Electroencephalograms (EEG) were acquired before and after each period.

Results: Treatment responses were observed after left hemisphere rTMS only. The 5 patients who showed a response did so already after 2 days. However, group mean hallucination scores did not differ across treatment conditions. No significant changes were found in EEG after rTMS.

Conclusions: A subgroup of patients suffering from AH benefits soon after treatment start from rTMS over the left superior temporal gyrus as revealed by the decrease of AH scores compared to right-sided and sham procedures.