Project Summary

Zafiris Daskalakis, M.D., Ph.D., FRCP (Young Investigator 2004) of Centre for Addiction and Mental Health of the University of Toronto, notes that repetitive transcranial magnetic stimulation (rTMS) as a treatment for refractory auditory hallucinations (AH) in patients with schizophrenia (SZ) has shown promising results. However, the underlying mechanisms as to how rTMS works are unclear. Dr. Daskalakis believes that cortical inhibition (CI) may represent one of these neurophysiological mechanisms. He previously demonstrated that CI deficits are related to the severity of psychotic symptoms, including AH in patients with schizophrenia. Additionally, drugs that disrupt CI have been associated with the development of AH, and electroconvulsive therapy (ECT)-mediated increases in slow wave (SW) activity and cortical GABA suggest that enhanced CI is related to and improvement in symptoms. Psychotic symptoms appear to have been lessened by antipsychotic-induced increases in SW in patients with SZ. He will investigate the relationship between improvements of AH in patients with SZ and SW activity following rTMS stimulation over the auditory cortex (AC). He will also seek to investigate CI as a potential mechanism through which rTMS exerts its therapeutic effects.

Program Area: SCHIZOPHRENIA/PSYCHOTIC DISORDERS\Schizophrenia

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