It’s only been as recent as 2008 that the FDA first cleared TMS as a therapy for depression. However, don’t let that fool you. TMS has been studied extensively since the 1980’s and has completed thousands of rigorous clinical trials. But TMS has a history even greater than that. Since the 18th century, we’ve known that magnets can potentially help us a great deal. Explore just how far we’ve come to what we have today!
The works of Luigi Galvani and Alessandro Volta are published. Their studies on electro-muscle stimulation lay the foundation for modern electrophysiology and bioelectric theory and provided physiologists with an early understanding of the mechanisms of neural and muscular excitation
Luigi Galvani discovers that muscles can be made to contract via zinc and copper electrodes. He incorrectly concludes that the contractions were the result of “animal electricity” released from storage in the muscle.
Alessandro Volta correctly proposes that the electrical stimulus responsible for the contraction is due to dissimilar electrical properties at the metal-tissue saline interfaces. It won’t be until 1800 that Volta can conclusively prove his theory.
Throughout the 19th century, continued advances are made in both electrophysiology and electromagnetic theory, laying the foundation for modern form of magnetic brain stimulation.
Michael Faraday first discovers the underlying principles of electromagnetic induction.
David Ferrier uses electrical currents to directly stimulate the cortex, indicating that the cortex holds a rather precise and specific map for motor functions.
Jacques-Arsène d’Arsonval presents the first report of magnetically induced phosphenes in human subjects by stimulation of the retina. His influential works will drastically promote the field of Electrophysiology.
Magnetic stimulation is still in its most primitive form as physicists study fundamental aspects of electromagnetics and in particular the implications of Faraday’s Law. A number of attempts to utilize electromagnetic induction are largely unsuccessful due to the lack of technology needed to create large and rapidly changing magnetic fields necessary for treatment.
After nearly a half-century of stagnant research in electrophysiology, the research group Kolin et al. releases a study that clearly demonstrates for the first time that time-varying magnetic fields can be used to initiate muscle contraction.
Researchers Bickford and Fremming stimulate peripheral nerves using an oscillating magnetic field, effectively demonstrating that human peripheral nerves can be excited by a magnetic coil.
A landmark program is started at the Royal Hallamshire Hospitaland University of Sheffield with the specific goal of stimulating cortical nerves by using currents induced by short duration magnetic field pulses. This work will serve as the precursor to developing a stable and reliable magnetic stimulator, later to be used as TMS.
The first demonstration of supramaximal stimulation of peripheral nerves is reported by the Sheffield Group. The design of a proven effective stimulator is described, which will become TMS.
The first successful study of Transcranial Magnetic Stimulation (TMS) is performed by the Sheffield Group. They will release the first safety guidelines for TMS two years later.
The decade sees thousands of clinical trials, which all prove the effectiveness and safety of TMS in stimulating the brain, particularly the cerebral cortex and prefrontal cortex.
TMS Therapy is approved for use in Canada.
TMS Therapy is cleared by the FDA as a treatment for depression.
An influential independent study by the National Institute of Mental Health (NIMH) runs sham-controlled trials of TMS and prove the efficacy of TMS Therapy for depression treatment.
TMS is currently being explored as a treatment for other conditions such as bipolar disorder, schizophrenia, OCD, and even PTSD.