Review Deep transcranial magnetic stimulation as a treatment for psychiatric disorders: A comprehensive review F.S. Bersani a, *, A. Minichino a , P.G. Enticott b , L. Mazzarini d,e , N. Khan a , G. Antonacci f , R.N. Raccah g , M. Salviati a , R. Delle Chiaie a , G. Bersani c , P.B. Fitzgerald b , M. Biondi a a Department of Neurology and Psychiatry, Sapienza University of Rome, Rome, Italy b Monash Alfred Psychiatry Research Centre, The Alfred and Central Clinical School, Monash University, Melbourne, Australia c Department of Medical–Surgical Sciences and Biotechnologies, Sapienza University of Rome, Rome, Italy d Neurosciences, Mental Health, and Sensory Organs Department, Sapienza University of Rome, Rome, Italy e Department of Neuropsychiatry, Villa Rosa, Suore Hospitaliere of the Sacred Heart of Jesus, Viterbo, Italy f Photonics Group, Department of Physics, Imperial College, London, UK g ATID Ltd Advanced Technology Innovation Distribution, Rome, Italy 1. Introduction Deep transcranial magnetic stimulation (TMS) is a technique of neuromodulation and neurostimulation based on the principle of electromagnetic induction of an electric field in the brain [72]. This field can be of sufficient magnitude and density to depolarize neurons, and when TMS pulses are applied repetitively they can modulate cortical excitability, decreasing or increasing it, depend- ing on the parameters of stimulation [26], even beyond the duration of the train of stimulation. This has behavioural consequences and therapeutic potential. Deep TMS is used for the treatment of drug-resistant major depressive disorder (MDD) and there are ongoing studies of its use to treat a very wide range of neurological, psychiatric and medical conditions such as Alzheimer’s disease, autism, Asperger’s disorder, substance addictions, alcoholism, tinnitus, bipolar depression (BPD), post-traumatic stress disorder, migraine, cognitive deficits, Parkinson’s disease, multiple sclerosis, neuro- pathic pain and schizophrenia. Deep TMS is a modification of standard TMS, which was originally invented by Barker et al. in 1985 and has been used from many years for medical and research purposes [2]. Standard TMS is mostly applied with an electromagnetic coil called a figure-of-eight coil (8-coil); deep TMS can be applied with different types of coils: the H-coil [71], the C-core coil [16] and the circular crown coil [18]. Among these, the only coil whose safety and effectiveness has been tested is the H-coil. Therefore it is the only one that has been used in clinical trials and the only one that will be reviewed in this text (Table 1). Both standard TMS and deep TMS can modulate (positively or negatively) cortical excitability, inducing changes in those neural circuits that are assumed to be dysfunctional. The 8-coil, used in standard TMS is able to modulate cortical excitability up to a maximum depth of 1.5–2.5 cm from the scalp; the H-coil, used in deep TMS, is able to modulate cortical excitability up to a maximum depth of 6 cm [72] and is therefore able, not only to European Psychiatry 28 (2013) 30–39 A R T I C L E I N F O Article history: Received 21 December 2011 Received in revised form 25 February 2012 Accepted 26 February 2012 Available online 3 May 2012 Keywords: Deep transcranial magnetic stimulation Transcranial magnetic stimulation H-coil Major depression Autism Bipolar disorder Auditory hallucinations Negative symptoms Schizophrenia A B S T R A C T Deep transcranial magnetic stimulation (TMS) is a technique of neuromodulation and neurostimulation based on the principle of electromagnetic induction of an electric field in the brain. The coil (H-coil) used in deep TMS is able to modulate cortical excitability up to a maximum depth of 6 cm and is therefore able not only to modulate the activity of the cerebral cortex but also the activity of deeper neural circuits. Deep TMS is largely used for the treatment of drug-resistant major depressive disorder (MDD) and is being tested to treat a very wide range of neurological, psychiatric and medical conditions. The aim of this review is to illustrate the biophysical principles of deep TMS, to explain the pathophysiological basis for its utilization in each psychiatric disorder (major depression, autism, bipolar depression, auditory hallucinations, negative symptoms of schizophrenia), to summarize the results presented thus far in the international scientific literature regarding the use of deep TMS in psychiatry, its side effects and its effects on cognitive functions. ß 2012 Elsevier Masson SAS. All rights reserved. * Corresponding author. Tel.: +39 3405165865; fax: +39 0649914728. E-mail address: bersani.fs@tiscali.it (F.S. Bersani). Available online at www.sciencedirect.com 0924-9338/$ – see front matter ß 2012 Elsevier Masson SAS. All rights reserved. doi:10.1016/j.eurpsy.2012.02.006