With an increase of the number of studies exploring repetitive
transcranial magnetic stimulation (rTMS) for the treatment of auditory verbal
hallucinations (AVH), an update is provided on the efficacy of different paradigms. A literature search was performed from 1966 through April 2013. Twenty-five randomized controlled trials using the severity of AVH or
psychosis as outcome measures were included. Standardized mean weighted effect sizes were computed; a qualitative review of the literature was performed to assess the effects of various rTMS paradigms. rTMS versus
sham treatment for AVH yielded a mean weighted effect size of .44. No significant mean weighted effect size was found for the severity of
psychosis (i.e., .21). For patients with medication-resistant AVH, the mean weighted effect size was .45. rTMS applied at the left temporoparietal area with a frequency of 1 Hz yielded a moderate mean weighted effect size of .63, indicating superiority of this paradigm. Various other paradigms failed to show superior effects. rTMS applied at the right temporoparietal area was not superior to
sham treatment. rTMS, especially when applied at the left temporoparietal area with a frequency of 1 Hz, is effective for the treatment of AVH, including in patients with medication-resistant AVH. The results for other rTMS paradigms are disappointing thus far. A next step should be to explore the effects of rTMS in medication-free individuals, for example, during the initial phases of
psychosis, and in patients with diagnoses other than
schizophrenia who do not have comorbid psychotic symptoms.