Transcranial Direct Current Stimulation (tDCS) and Hallucinations in Schizophrenia

Study Overview
=================
Brief Summary
-----------------
The purpose of this study is to determine whether trans Direct Current Stimulation (tDCS) is effective in the treatment of auditory hallucinations in schizophrenia.

Detailed Description
-----------------
The project will investigate the use of a novel technique, transcranial direct current stimulation (tDCS) in the treatment of patients with schizophrenia. tDCS permit the application of an extremely weak continuous electrical current to the brain through an anode and a cathode applied on the scalp. Anodal stimulation appears to increase brain activity whereas cathodal stimulation has the opposite effect. Using anodal & cathodal tDCS the investigators aimed to treat auditory hallucinations, a symptoms of schizophrenia. The investigators plan to apply tDCS such that it can simultaneously increased activity in the frontal brain areas and reduce activity over temporoparietal cortex, 2 areas involved in the physiopathology of the disease. Real active stimulation will be compare to a sham condition in 60 patients (30 in each group). 30 patients will be included in a French center (Hospital le Vinatier, sponsor of the study) and 30 in Tunisia (laboratory vulnerability to psychosis (Pr Gaha) à Monastir).

Official Title
-----------------
Anodal & Cathodal tDCS for Treatment of Resistant Auditory Hallucinations in Schizophrenia

Conditions
-----------------
Schizophrenia, Auditory Hallucinations

Intervention / Treatment
-----------------
* Procedure: active tDCS
* Procedure: sham tDCS


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Schizophrenia according to Diagnostic and Statistical Manual - DSM-IV Auditory verbal hallucinations for at least 6 weeks (despite antipsychotic drugs) Medication Resistance according to Kane et al., 1988 Age between 18 and 50 years old Informed consent Exclusion Criteria: Concomitant major and unstable medical or neurologic illness Pregnant

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 50 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: active tDCS<br>tDCS active; - Intensity = 2 milliamps (mA) during 20 minutes. ramp up/ramp down 30sec anodal tDCS applied over the left DLPFC combined with cathodal tDCS applied over the left temporoparietal junction (TPJ). 10 sessions, 2 per day | Procedure: active tDCS<br>* Intensity 2 mA during 20 minutes, 2 times per day<br>* Other names: Cathodal tDCS;|
| Placebo Comparator: sham tDCS<br>tDCS placebo same electrode montage than in the active group. 30 sec of active tDCS in the beginning of the stimulation sessions; ramp up/ramp down 30 sec | Procedure: sham tDCS<br>* sham condition as delivered by the stimulator<br>* Other names: tDCS placebo;|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Auditory hallucinations measured by Auditory Hallucination Rating Scale (Hoffman et al., 2003) |  | before, after 1 week of treatment and 2 times follow up (1 & 3 months) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Neurochemical impact of treatment measured by 1H-MRS (proton Magnetic Resonance Spectroscopy), DTI (Diffusion Tensor Imaging) and resting MRI |  | 3 times: before treatment, immediately after treatment and a last evaluation 1 month after |