Transcranial Magnetic Stimulation in the investigation and treatment of schizophrenia: a review

• Published in: Schizophrenia research 2004-11, Vol.71 (1), p.1-16
• Main Authors: Haraldsson, H.Magnus, Ferrarelli, Fabio, Kalin, Ned H., Tononi, Giulio
• Format: Article
• Language: English
• Subjects: Adult and adolescent clinical studies; Antipsychotic medications; Auditory Cortex - physiopathology; Biological and medical sciences; Cortical excitability; Cortical inhibition; Functional brain imaging; Functional Laterality - physiology; Hallucinations - prevention & control; Humans; Medical sciences; Neural Inhibition - physiology; Prefrontal Cortex - physiopathology; Psychology. Psychoanalysis. Psychiatry; Psychopathology. Psychiatry; Psychoses; Psychotic Disorders - prevention & control; Psychotic Disorders - psychology; Schizophrenia; Schizophrenia - diagnosis; Schizophrenia - physiopathology; Schizophrenia - therapy; Skull; Transcranial Magnetic Stimulation; Transcranial Magnetic Stimulation - instrumentation
• ISSN: 0920-9964; 1573-2509
• DOI: 10.1016/j.schres.2003.10.006

Transcranial Magnetic Stimulation (TMS) is a non-invasive method of stimulating the brain that is increasingly being used in neuropsychiatric research and clinical psychiatry. This review examines the role of TMS in schizophrenia research as a diagnostic and a therapeutic resource. After a brief overview of TMS, we describe the application of TMS to schizophrenia in studies of cortical excitability and inhibition, and we discuss the potential confounding role of neuroleptic medications. Based on these studies, it appears that some impairment of cortical inhibition may be present in schizophrenic subjects. We then review attempts to employ TMS for treating different symptoms of schizophrenia. Some encouraging results have been obtained, such as the reduction of auditory hallucinations after slow TMS over auditory cortex and an improvement of psychotic symptoms after high frequency TMS over left prefrontal cortex. However, these results need to be confirmed using better placebo conditions. Future studies are likely to employ TMS in combination with functional brain imaging to examine the effects produced by the stimulated area on activity in other brain regions. Such studies may reveal impaired effective connectivity between specific brain areas, which could identify these regions as targets for selective stimulation with therapeutic doses of TMS.