TDCS for Auditory Hallucinations in Schizophrenia
Condition: Schizophrenia
MeSH terms: Hallucinations; Schizophrenia
Study type: Interventional

Summary: 
      The purpose of the present research is to test a potential new treatment for auditory verbal
      hallucinations in schizophrenia that uses transcranial Direct Current Stimulation (tDCS), a
      neurostimulation technique that passes an extremely weak electric current through the brain.
      During the treatment, two electrodes are positioned on the scalp above regions of the brain
      implicated in abnormal cortical activity associated with auditory verbal hallucinations in
      schizophrenia. Due to the directional flow of current, one electrode, termed
      "cathodal",inhibits cortical activity, and the other, termed "anodal", increases cortical
      activity. These electrodes will be placed such that cathodal stimulation is applied to an
      area associated with hyperactivity and anodal stimulation to an area associated with
      hypoactivity. One preliminary study has revealed that this form of neurostimulation can
      alleviate auditory verbal hallucination symptoms both immediately following five days of
      treatment and up to three months after the final treatment. The goal of this study is to
      replicate these effects and explore the mechanisms that may underpin them.
    

Detailed description: 
      90 patients with persistent auditory verbal hallucinations will be recruited to this study.
      Each individual will participate in behavioral assessments lasting up to 3 hours each and
      will then be randomized to receive a series of active vs. sham tDCS treatments. For active
      treatment, patients will have the inhibitory (cathodal) tDCS electrode placed over left
      auditory cortex relative to an anodal placed over frontal cortex on the right side. tDCS
      treatments will take place for 20 min per day for 5 consecutive days. For sham, procedures
      will be similar except that sham (inactive) tDCS treatment will be used. Assessment batteries
      will then be repeated following completion of treatment and at 1 and 3 mo following
      treatment. In addition, patients will be offered the possibility to participate in a
      concurrent magnetic resonance imaging (MRI) study aimed at evaluating the effects of tDCS on
      activation of auditory cortex during an auditory discrimination task as well as on other
      imaging parameters related to resting brain activity and metabolism. Patients who agree to
      participate in this MRI study will be scanned before and after active or sham tDCS. In
      addition, 5-15 schizophrenia patients will complete a week of High-density, e.g.,
      "high-definition" tDCS (HD-tDCS) open label.

      In addition to hallucinating patients, we will recruit up to 20 healthy controls and 20
      non-hallucinating patients, who will have similar assessments to the patients, but will not
      receive tDCS.

      Overall, the investigators hypothesize that tDCS treatment will lead to reduction in
      hallucinations, improvement in auditory function, and change in EEG and MRI measurements so
      that patients more closely resemble healthy volunteers and non-hallucinating patients.
    

Intervention name(s): transcranial Direct Current Stimulation (tDCS); Sham tDCS
Intervention type(s): Device; Device
Intervention description(s): A neurostimulation technique that passes an extremely weak electric current through the brain.; Sham (inactive) tDCS treatment
Other intervention name(s): BrainStim SYS
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Triple (Participant, Investigator, Outcomes Assessor)
Primary purpose: Treatment
Keywords: Schizophrenia