Grant: CIHR Fellowship

Auditory verbal hallucinations (AVHs), or "voice hearing" are common in people with schizophrenia and typically have a negative effect on daily function. Brain scan studies suggest that voice hearing may arise from abnormal activity in, and connections between, brain regions involved in sound and speech processing, though the underlying brain features are not well understood. Importantly, voice hearing is not effectively treated with currently available drugs. As such, persistent voice hearing can severely impact an individual's life. A non-invasive brain stimulation technique called transcranial direct current stimulation (tDCS) may alleviate voice hearing. This study will explore the effects of tDCS for treating voice hearing in persons with schizophrenia. It will also study associated changes in brain activity to understand how tDCS works. Fifty-six people with schizophrenia who hear voices will be included. They will randomly be assigned to receive active (n=28) or sham (fake) tDCS (n=28) twice a day for five consecutive days. Active tDCS will apply a low electrical current for 20min that might modify underlying brain activity. Sham tDCS will not affect brain activity. We will measure changes in ratings of voices (e.g., how disruptive they are) and brain activity before and after tDCS. This work will provide valuable information on the effects of tDCS for treating voice hearing. Second, it will reveal the brain features that underlie voice hearing, and how these may be changed with tDCS. Such insight is critical for optimizing treatment, which has the potential to increase quality of life and reduce burdens on the healthcare system.