STimulation to Improve Auditory haLLucinations

Targeting Auditory Hallucinations With Alternating Current Stimulation

Investigating the effects of non-invasive transcranial current stimulation as a treatment for auditory hallucinations in patients with schizophrenia.

The investigator's primary objective is to conduct a pilot clinical trial to establish the feasibility and to collect first effectiveness data for the use of transcranial alternating current stimulation (tACS) to re-normalize pathological alpha oscillations in dorso-lateral prefrontal cortex (dl-PFC) of patients with schizophrenia or schizoaffective disorder by comparing Auditory Hallucination Rating Scale (AHRS) scores immediately before the first stimulation session and immediately after the last stimulation session. As a secondary objective the investigators will assess the differential clinical effects of sham, 10 Hz and 2 mA transcranial direct current stimulation (tDCS) on electroencephalogram (EEG) measures of alpha oscillations.

Inclusion Criteria:

• DSM-IV diagnosis of schizophrenia, any subtype, or schizoaffective disorder, with refractory auditory hallucinations. Duration of illness >1 year
• 18-70 years old
• Clinically stable for at least 12 weeks, i.e. not requiring hospitalization or a change in level of care
• On current antipsychotic doses for at least 4 weeks
• Stable auditory hallucinations as demonstrated by having less than or equal to 20% change in AHRS scores across a 2 week interval during the screening period.
• Capacity to understand all relevant risks and potential benefits of the study and to provide written informed consent, OR has a legal guardian who can provide informed consent on the patient's behalf with the patient providing written assent to participate.

Exclusion Criteria:

• DSM-IV diagnosis of alcohol of substance abuse (other than nicotine) within the last month or a DSM-IV diagnosis of alcohol or substance dependence (other than nicotine) within the last 6 months
• Medical or neurological illness (unstable cardiac disease, AIDS, malignancy, liver or renal impairment) or treatment for a medical disorder that could interfere with study participation
• History of traumatic brain injury that required subsequent cognitive rehabilitation, or caused cognitive sequelae
• Prior brain surgery
• Any brain devices/implants, including cochlear implants and aneurysm clips
• Co-morbid neurological condition (e.g. seizure disorder, brain tumor)
• Non English speakers
• Female participants who are pregnant, nursing, or unwilling to use an adequate method of contraception during study participation for those of childbearing potential
• Positive urine test for cannabis, cocaine, amphetamine, barbiturates, benzodiazepines, opiates