Magnetic Stimulation for Auditory Hallucinations: Safety, Efficacy and Moderators in a Fifty Patient Sample

TITLE
Magnetic Stimulation for Auditory Hallucinations: Safety, Efficacy and Moderators in a Fifty Patient Sample

AUTHORS
Ralph E. Hoffman, Michelle Hampson, Kun Wu, Adam W. Anderson, John C. Gore, Robert J. Buchanan, R. Todd Constable, Keith A. Hawkins, Neayka Sahay, John H. Krystal

SOURCE
The Lancet. Volume 355, Issue 9209, 25 March 2000, Pages 1073-1075

BACKGROUND
Auditory hallucinations are often resistant to treatment and can produce significant distress and behavioral difficulties. A preliminary report based on 24 patients with schizophrenia or schizoaffective disorder indicated greater improvement in auditory hallucinations following 1-hertz left temporoparietal repetitive transcranial magnetic stimulation (rTMS) compared to sham stimulation. Data from the full 50-subject sample incorporating 26 new patients are now presented to more comprehensively assess safety/tolerability, efficacy and moderators of this intervention.

METHODS
Right-handed patients experiencing auditory hallucinations at least 5 times per day were randomly allocated to receive either rTMS or sham stimulation. A total of 132 minutes of rTMS was administered over 9 days at 90% motor threshold using a double-masked, sham-controlled, parallel design.

RESULTS
Hallucination Change Score was more improved for rTMS relative to sham stimulation (p = .008) as was the Clinical Global Impressions Scale (p = .0004). Hallucination frequency was significantly decreased during rTMS relative to sham stimulation (p = .0014) and was a moderator of rTMS effects (p = .008). There was no evidence of neurocognitive impairment associated with rTMS.

CONCLUSIONS
Left temporoparietal 1-hertz rTMS warrants further study as an intervention for auditory hallucinations. Data suggest that this intervention selectively alters neurobiological factors determining frequency of these hallucinations.