7 June 2012. For 25%-30% of people with schizophrenia, auditory hallucinations continue mostly unabated despite treatment with antipsychotic drugs. According to a study published online 11 May in the American Journal of Psychiatry, non-invasive brain stimulation may quell these diehard symptoms. Led by Jerome Brunelin of the University of Lyon, France, the study reports that transcranial direct current stimulation (tDCS) significantly reduced the severity of these remaining hallucinations by 31% compared to an 8% reduction in the group receiving sham stimulation. This reduction persisted three months following the 5-day course of tDCS treatment, and no adverse effects were detected.
The results suggest that non-invasive ways of shifting brain activity may successfully treat hallucinations. Like repetitive transcranial magnetic stimulation (rTMS), tDCS is thought to work by changing neural excitability in brain regions underneath the stimulation sites on the scalp. Unlike rTMS however, tDCS can simultaneously increase and decrease neuron excitability in two different regions. Brunelin and colleagues employed this ability in order to deliver excitatory stimulation over an area of prefrontal cortex and inhibitory stimulation over the left temporo-parietal cortex – both regions implicated in auditory hallucinations. Though based on only 30 people with treatment-resistant hallucinations, the findings urge further exploration of tDCS in larger sample sizes.—Michele Solis.
Brunelin J, Mondino M, Gassab L, Haesebaert F, Gaha L, Suaud-Chagny MF, Saoud M, Mechri A, Poulet E. Examining Transcranial Direct-Current Stimulation (tDCS) as a Treatment for Hallucinations in Schizophrenia. Am J Psychiatry. 2012 May 11.