From the Guidelines
Transcranial Magnetic Stimulation (TMS) is a non-invasive brain stimulation technique that uses brief, high intensity magnetic field pulses to modify neural activity, as evidenced by a meta-analysis published in 2019 1.
Definition and Mechanism
TMS can be administered using two different paradigms, “online” and “offline”, and has become a widely used research tool for studying the involvement of brain regions underlying cognitive processes such as attention, memory, language, and perception.
- The technique involves the use of an electromagnetic coil placed against the scalp, generating magnetic pulses that stimulate nerve cells in specific brain regions.
- TMS has been shown to affect performance on cognitive tasks when applied over a central node of a brain network hypothesized to support a targeted cognitive function.
Clinical Applications
While the provided evidence primarily focuses on the cognitive effects of repetitive TMS (rTMS), the most recent and relevant study published in 2019 1 highlights the potential of TMS in modifying neural activity, which can have implications for various neurological and psychiatric conditions.
- However, it is essential to note that the provided evidence does not directly address the clinical applications of TMS, and therefore, the recommendation is based on the most recent and highest quality study available, which emphasizes the technique's potential in cognitive processing 1.
- Other studies, such as the 2024 consensus-based core recommendations for stroke rehabilitation 1, may provide additional context, but the primary focus remains on the most recent and relevant evidence 1.
From the Research
Definition and Mechanism of Transcranial Magnetic Stimulation (TMS)
- Transcranial Magnetic Stimulation (TMS) is a non-invasive method that produces neural excitation in the cortex by means of brief, time-varying magnetic field pulses 2.
- TMS is based on the phenomenon of electromagnetic mutual induction, which was first reported by Michael Faraday in 1831 3.
- The technique uses brief electromagnetic pulses generated by an insulated coil, placed over the scalp, to modulate the cortical activity of the brain 3.
Types of TMS
- Repetitive Transcranial Magnetic Stimulation (rTMS) is a type of TMS that involves the application of repeated magnetic pulses to the brain 4, 3.
- Theta Burst Stimulation (TBS) is a type of TMS that involves the application of brief bursts of magnetic pulses to the brain 5.
- Other types of TMS include accelerated rTMS (aTMS), deep TMS (dTMS), priming TMS (pTMS), and synchronized TMS (sTMS) 4.
Applications of TMS
- TMS is approved by the FDA for the treatment of medication-resistant depression 4, 3.
- TMS has also been shown to be effective in reducing symptoms of other neuropsychiatric disorders, such as migraines and OCD 3.
- TMS can be used to modulate the cortical activity of the brain, and has been shown to induce brain morphological changes in regions associated with treatment-resistant major depressive episodes 6.
Techniques and Protocols
- TMS can be combined with simultaneous electroencephalography (EEG) and neuronavigation (nTMS-EEG) to assess cortico-cortical excitability and connectivity in almost all cortical areas 2.
- The optimal parameters for dorsolateral prefrontal (DLPFC) stimulation are not fully known, and current protocols utilize variations from the motor cortex (M1) stimulation paradigms 2.
- TMS treatment targets can be guided using functional brain connectivity, such as the coordinate of peak effective connectivity from the right anterior insula to the left dorsolateral prefrontal cortex 5.