Transcranial magnetic stimulation

Related Terms

Cortical modulation, magnet therapy, magnetic stimulation, neuropsychology, repetitive transcranial magnetic stimulation, rTMS.

Background

Repetitive transcranial magnetic stimulation (rTMS) was developed by scientists in the 1980s as a tool for neurodiagnosis, nerve fiber study and the development of a functional brain map.
In the late 1980s, scientists started to use repetitive transcranial magnetic stimulation for the treatment of depression.
Over time, the use of rTMS has expanded and is currently not only used for the treatment of depression, but also to treat Parkinson's disease, auditory hallucination schizophrenia, tinnitus, migraines, eating disorders, obsessive compulsive disorder as well as other mood disorders.
rTMS is a more specific form of magnet therapy. Magnet therapy is the use of magnets to provide health benefits. rTMS uses a coil rather than a magnet to produce an electrical current and is specifically used on the scalp. Magnet therapy can generally be preformed on any part of the body affected by a specific ailment.

Theory / Evidence

Depression is thought to be caused by a disturbance in activity in the frontal cortex of the brain. When the rTMS device is held close to the scalp, it allows for the non-invasive induction of a current of neurons. This induction is hypothesized to down regulate beta-adrenergic receptors and to subsequently increase the levels of dopamine and serotonin in the brain. While reported to be safe and painless, some patients do experience a headache, which typically resolves in a few hours and can be treated with acetaminophen.
Based on one randomized control trial, rTMS has been proven to be effective in the treatment of treatment resistant depression. An additional study examined the effect of rTMS on depression in adolescent patients. rTMS again proved to be effective and safe in this randomized control trial. Further research is being conducted as to whether rTMS has equal efficacy in the other areas of use.

Author information

This information has been edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com).

Bibliography

Bretlau LG, Lunde M, Lindberg L, et al. Repetitive transcranial magnetic stimulation (rTMS) in combination with escitalopram in patients with treatment-resistant major depression: a double-blind, randomised, sham-controlled trial. Pharmacopsychiatry. 2008 Mar;41(2):41-7.
Fitzgerald PB, Benitez J, deCastella A, et al. A randomized, controlled trial of sequential bilateral repetitive transcranial magnetic stimulation for treatment-resistant depression. Am J Psychiatry. 2006 Jan;163(1):88-94.
Fitzgerald PB, Daskalakis ZJ. The use of repetitive transcranial magnetic stimulation and vagal nerve stimulation in the treatment of depression. Curr Opin Psychiatry. 2008 Jan;21(1):25-9.
Jorge RE, Moser DJ, Acion L, et al. Treatment of vascular depression using repetitive transcranial magnetic stimulation. Arch Gen Psychiatry. 2008 Mar;65(3):268-76.
Khedr EM, Rothwell JC, Ahmed MA, et al. Effect of daily repetitive transcranial magnetic stimulation for treatment of tinnitus: comparison of different stimulus frequencies. J Neurol Neurosurg Psychiatry. 2008 Feb;79(2):212-5.
Landgrebe M, Binder H, Koller M, et al. Design of a placebo-controlled, randomized study of the efficacy of repetitive transcranial magnetic stimulation for the treatment of chronic tinnitus. BMC Psychiatry. 2008 Apr 15;8:23.
Lee SL, Abraham M, Cacace AT, et al. Repetitive transcranial magnetic stimulation in veterans with debilitating tinnitus: a pilot study. Otolaryngol Head Neck Surg. 2008 Mar;138(3):398-9. PMID:
Loo C, McFarquhar T, Walter G. Transcranial magnetic stimulation in adolescent depression. Transcranial magnetic stimulation in adolescent depression. Australas Psychiatry. 2006 Mar;14(1):81-5.
Walpoth M, Hoertnagl C, Mangweth-Matzek B, et al. Repetitive transcranial magnetic stimulation in bulimia nervosa: preliminary results of a single-centre, randomised, double-blind, sham-controlled trial in female outpatients. Psychother Psychosom. 2008;77(1):57-60.

Technique

Repetitive transcranial magnetic stimulation is a procedure in which electrical activity in the brain is influenced by a pulsed magnetic field generated by brief current pulses through figure eight coils of wire. These wires are encased in plastic and held close to the scalp. The location of the device allows for stimulation of specific areas of the cortex (the surface of the brain).
rTMS is non invasive and requires no anesthesia. Few patients report any serious side effects. Mild side effects include headache and the perception of unwanted noise. These problems usually are treated with acetaminophen (Tylenol) and ear plugs respectively.