Transcranial Magnetic Stimulation and Deep Brain Stimulation in Neuropsychiatric Disorders: New Dimension of Therapeutic Markers in Psychiatry

Lebanon. Email: [email protected] 3 Faculty of Medicine, Saint George University of London, Nicosia, Cyprus. Email: [email protected] 4 Department of Biochemistry and Molecular Genetics, American University of Beirut, Beirut, Lebanon. Email: [email protected] 5 Department of Psychiatry, American University of Beirut Medical Center, Beirut, Lebanon. * Corresponding author_ [email protected] Neuropsychiatric disorders are widely prevalent and lead to the disability of millions worldwide with three disorders listed by the World Health Organization (WHO) among the top 10 causes of disability worldwide. The main contributors of the chronicity and unresponsiveness to treatment of these disorders are our incomplete understanding of the pathophysiology of the diseases, our limited therapeutic arsenal and our phenomenological approach in diagnosis (Nahas, 2010). Several biomarkers using neuroimaging techniques, biochemical and genetic tests have been identifi ed, but most lack exact sensitivity or specifi city. The fi eld of neuromodulation is advancing at a rapid pace. Brain stimulation techniques are promising for treatments of many neuropsychiatric diseases including depression, schizophrenia, Parkinson’s Disease (PD), Obsessive-Compulsive Disorder (OCD) and Tourette’s Syndrome (TS). They also aid in the development of other new treatments that incorporate neurogenesis via stem cells, viral vectors and transgenic cells. Although much is known about their action on brain networks, their exact therapeutic mechanism is yet to be agreed upon. This chapter focuses on two specifi c techniques at the opposite spectrum of invasiveness: Deep Brain Stimulation (DBS) and Transcranial Magnetic Stimulation (TMS).