Role Of Transcranial Magnetic Stimulation Research Articles

Transcranial magnetic stimulation in the treatment of depression.

Transcranial magnetic stimulation (TMS) is a noninvasive and easily tolerated method of altering cortical physiology. The authors evaluate evidence from the last decade supporting a possible role for TMS in the treatment of depression and explore clinical and technical considerations that might bear on treatment success. The authors review English-language controlled studies of nonconvulsive TMS therapy for depression that appeared in the MEDLINE database through early 2002, as well as one study that was in press in 2002 and was published in 2003. In addition, the authors discuss studies that have examined technical, methodological, and clinical treatment parameters of TMS. Most data support an antidepressant effect of high-frequency repetitive TMS administered to the left prefrontal cortex. The absence of psychosis, younger age, and certain brain physiologic markers might predict treatment success. Technical parameters possibly affecting treatment success include intensity and duration of treatment, but these suggestions require systematic testing. TMS shows promise as a novel antidepressant treatment. Systematic and large-scale studies are needed to identify patient populations most likely to benefit and treatment parameters most likely to produce success. In addition to its potential clinical role, TMS promises to provide insights into the pathophysiology of depression through research designs in which the ability of TMS to alter brain activity is coupled with functional neuroimaging.

The role of transcranial magnetic stimulation (TMS) in studies of vision, attention and cognition

Transcranial magnetic stimulation (TMS) can be conceptualized as a virtual lesion technique, capable of disrupting organized cortical activity, transiently and reversibly. The technique combines good spatial and temporal resolution and, moreover, because it represents an interference technique, can be said to have excellent functional resolution. The following is a review and discussion of the contribution which TMS has made to the study of vision, attention, development and plasticity and speech and language.

Transcranial Magnetic Stimulation in Neuropsychiatry

Back to table of contents Previous article Next article Book ReviewsFull AccessTranscranial Magnetic Stimulation in NeuropsychiatryShirlene M. Sampson, M.D.Shirlene M. SampsonSearch for more papers by this author, M.D.Published Online:1 Nov 2000AboutSectionsView EPUB ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InEmail Transcranial magnetic stimulation (TMS) is an exciting new technology in which a rapid, brief magnetic pulse induces a secondary current in brain tissue. In addition to being a novel means of brain stimulation, it is unique in that it can be used to study brain neurophysiology and may have therapeutic applications for a number of neuropsychiatric disorders. TMS has been a rapidly growing subject of research since its initial development in 1985 and has been used by researchers from multiple disciplines (e.g., neurologists, neuroscientists, physicists, psychiatrists, and psychologists).Because TMS is a technology with multiple applications, any book reviewing this topic has the challenge of meeting the needs of readers with differing interests. This book is a comprehensive yet basic and readable TMS primer covering a broad spectrum of issues in TMS research, and it will likely serve the needs of readers from multiple disciplines.The book progresses logically from the historical origins of TMS, reviewed by the editors, to the physics involved in this technology, reviewed by Dr. Bohning. The overview of TMS physics begins with the basics; however, the discussion of complex mathematics is likely more than most readers require. Clearly there was an attempt to combine information for those wishing to become proficient in using TMS and those seeking a basic understanding of this technology and its potential future role in neuropsychiatry.Drs. Ziemann and Hallett have authored an impressive, clearly presented review of the basic neurophysiological studies that are possible with TMS. Although much of the current interest in TMS has focused on potential therapeutic benefits, this chapter is very important in describing the range of applications for TMS in studying basic brain physiology. These techniques can be useful in increasing our understanding of neurophysiology in both normal subjects and those with neurologic and psychiatric disorders.Dr. Belmaker and colleagues review the use of TMS to study mood disorder models in animals. Responses to TMS stimulation are compared with those of electroconvulsive shock studies (an animal model for ECT in humans). This review is brief, owing to the limited number of studies to date. In a separate chapter, the significant potential role of TMS in cognitive neuroscience is addressed in a review of TMS as a brain mapping tool.Drs. Lorberbaum and Wasserman offer an essential, practical review of safety issues for both single-pulse and repetitive TMS (rTMS). Seizure induction, the primary safety concern in using rTMS, is reviewed in terms of experience to date and guidelines for minimizing seizure risk.The use of TMS in clinical disorders is reviewed for hypokinetic movement disorders (primarily Parkinson's disease), epilepsy, depression, bipolar disorder, anxiety disorders, developmental stuttering and Tourette's syndrome, and schizophrenia.To date, the therapeutic role of TMS has been best studied in depression. However, many of the studies have varied in design, stimulation parameters, and type of TMS used. The reference charts provided in the review of TMS in major depression by Drs. Lisanby and Sackeim are very useful for comparing this broad range of studies. Another practical feature of this review is a figure displaying the various sham conditions that have been employed, since these are difficult to understand through a verbal description alone. Understanding the type of sham used in controlled studies is important because more recent data suggest that some sham manipulations may be partially active.The remaining chapters review TMS in other clinical disorders. The authors clearly present the limited research available in these areas and discuss future directions for research.Dr. George and colleagues review the use of TMS in combination with various neuroimaging procedures and discuss the outlook for combining these technologies. The book concludes with a discussion of rTMS and future therapeutic applications by Drs. Post and Speer.This book is very readable, is authored by leading researchers in multiple areas of TMS research, and has thorough listings of TMS references, most very recent. It is an excellent resource for understanding the broad range of TMS research performed to date and will likely be useful to both experienced researchers and interested novices.Dr. Sampson is Instructor and Associate Director for TMS in the Neuropsychiatric Therapeutic Procedures Program, Mayo Medical School, Rochester, MN.Edited by Mark S. George and Robert H. Belmaker, Washington, DC, American Psychiatric Press, 2000, 320 pages, ISBN 0-88048-948-0, $44.00 FiguresReferencesCited byDetailsCited ByRevista Brasileira de Psiquiatria, Vol. 40, No. 1 Volume 12Issue 4 November 2000Pages 512-513 Metrics History Published online 1 November 2000 Published in print 1 November 2000

Transcranial magnetic stimulation: applications in basic neuroscience and neuropsychopharmacology.

Introduced 15 years ago, transcranial magnetic stimulation (TMS) is a non-invasive means of stimulating the cortex that has proved to be a unique tool for probing brain-behaviour relationships. While a therapeutic role for TMS in neuropsychiatry is uncertain, the utility of TMS in studying brain function has been demonstrated in diverse neuroscience applications. We review studies in animals on the mechanisms of action of TMS, and present a summary of the applications of TMS in basic neuroscience. TMS is still a relatively young technique, and unanswered questions remain regarding its acute and chronic impact on neural excitability and various aspects of brain function. Nonetheless, recent work with TMS has demonstrated its unique role in complementing other tools for studying brain function. As a brain intervention tool, TMS holds the promise of moving beyond correlative studies to help define the functional role of cortical regions in selected cognitive and affective processes.

Magnetic Stimulation of the Brain in Animal Depression Models Responsive to ECS

Studies in humans show antidepressant potential for transcranial magnetic stimulation (TMS). We therefore studied TMS in animal models of depression and compared its effects with those of ECS. ECS in rats has several robust behavioral effects, including enhancement of apomorphine-induced stereotypy, reduction of immobility time in the Porsolt swim test, and increases in seizure threshold for subsequent stimulation. Seven or 10 days of daily TMS consistently enhanced apomorphine-induced stereotypy, whereas a single session of TMS did not. Two TMS treatments markedly reduced immobility in the Porsolt swim test, as does ECS. A single TMS treatment markedly reduces the percentage of rats seizing in response to a ECS-like electrical stimulus to the brain 10 s later, as does an ECS treatment itself but not a sub-convulsive electrical stimulus to the brain. Long-term administration of ECS as well as other antidepressant treatments downregulates beta-adrenergic receptors. We found that TMS significantly reduced the density of [3H]CGP-12177 (a radioligand with beta-adrenergic affinity) binding sites in cortical (p < 0.05) but not hippocampal membranes. The role of monoamines in the mechanism of action of antidepressant treatments was investigated in numerous studies. Region-specific changes in the brain steady-state levels, and turnover rates of monoamines were detected 10 s after administration of a single repetitive TMS (rTMS) session. In the striatum and hippocampus, dopamine levels were increased by 25 +/- 1.5% and 18 +/- 0.8%, respectively, but were reduced in frontal cortex and decreased in the striatum and hippocampus in the TMS-treated rats with no change to the midbrain. TMS caused an increase in serotonin and 5-HIAA levels in the hippocampus but not in other brain regions examined in this study. The ability of TMS to induce behavioral and biochemical alterations similar to those of ECS may further support the potential role of TMS as an antidepressant treatment and bring us closer to the understanding of the mechanism of action of TMS.

Transcranial magnetic stimulation: its current role in epilepsy research.

This paper reviews the current role of transcranial magnetic stimulation (TMS) in epilepsy research. After a brief introduction to the technical principles, the physiology and the safety aspects of TMS, emphasis is put on how human cortex excitability can be assessed by TMS and how this may improve our understanding of pathophysiological mechanisms in epilepsy and the mode of action of antiepileptic drugs (AEDs). Also, potential therapeutical applications of TMS are reviewed. For all aspects of this paper, a clear distinction was made between single-/paired-pulse TMS and repetitive TMS, since these two techniques have fundamentally different scopes and applications.

Clinical application of TMS to epilepsy.

The role of transcranial magnetic stimulation in epileptology is discussed in this article. Usefulness of TMS are discussed as a diagnostic tool in testing altered cortical excitability in patients with epilepsy and the modes of action of antiepileptic drugs, which are helpful to evaluate the pathophysiology of epilepsy. Also potential therapeutic tool in epilepsy with repetitive transcranial magnetic stimulation would be mentioned.