Electrical and Magnetic Brain Stimulation: How They Differ
Plain-language differences between magnetic and electrical brain stimulation, from TMS and tDCS to ECT, vagus nerve stimulation and deep brain stimulation, with no winner declared.
Content last updated . This page has not been medically reviewed.
Why the names get confused
"Brain stimulation" covers very different things. The U.S. National Institute of Mental Health describes brain stimulation therapies as working by activating or inhibiting the brain with electricity, delivered either through electrodes implanted in the brain, through electrodes on the scalp, or induced by magnetic fields applied to the head. [1] A technology (such as a magnetic coil), a specific device, an approved use and a research idea are four different things. This page covers the first; approval is always specific to a product and use, as explained in device-specific approval for brain stimulation.How they differ
| Approach | How the stimulation reaches the brain | Setting and procedure |
|---|---|---|
| Repetitive transcranial magnetic stimulation (rTMS) | An electromagnet held against the head induces weak electrical currents in nerve cells; stimulation is aimed at a specific brain site [1] | No anesthesia; done in a clinical or office setting [1] |
| Transcranial direct current stimulation (tDCS) | Low-intensity direct electrical current through electrodes placed on the scalp [2] | Mostly research, plus at least one FDA-approved headset evaluated for at-home treatment (see tDCS and tACS) |
| Transcranial alternating current stimulation (tACS) | Studied as a way to modulate neural oscillations in conditions such as depression [3] | Research evidence only so far (see the tDCS and tACS page) |
| Electroconvulsive therapy (ECT) | An electric current is used to induce seizure activity in the brain [1] | Sedation with a muscle relaxant is used for most of these procedures [1] |
| Vagus nerve stimulation (VNS) | An implanted device sends pulses along the left vagus nerve; noninvasive forms use skin-surface stimulation [1] | Surgery for the implanted type; see vagus nerve stimulation |
| Deep brain stimulation (DBS) | Electrodes placed in the brain through surgery [1] | Brain surgery, which carries the risks of any brain surgery [1] |
NIMH notes that rTMS is targeted to a specific site, unlike ECT where stimulation is generalized. [1]
What the comparison research can and cannot say
A network meta-analysis in the BMJ pooled 113 randomized trials (6,750 patients) of non-surgical brain stimulation for depressive episodes. [4] Ten of 18 treatment strategies were linked to higher response than sham, including high-frequency left rTMS and tDCS, and ECT variants were linked to higher response than other active treatments. [4] The authors also noted that the precision of estimates varied considerably. [4]How to read that: it is evidence about depression, in the trials that were done, and says little about other conditions. It does not make one tool "the best" for any individual. Choices depend on the condition, earlier treatments, safety history and what a clinician judges suitable. See neuromodulation for depression.
Common mix-ups
- "Magnetic" does not mean "weaker" or "safer". Each approach has its own side effects and exclusions. See contraindications and seizure considerations.
- Clinical devices and consumer headsets are not interchangeable. See clinical vs consumer brain stimulation devices. Consumer neurotechnology comparisons live in the Biohacking area.
- A change on a brain scan or EEG is not a clinical benefit. See clinical outcomes vs brain-signal changes.
Frequently asked questions
What is the main difference between TMS and tDCS?
TMS uses a magnetic field to induce small electrical currents at a targeted site. [1] tDCS sends low-intensity direct current through scalp electrodes. [2]
Is ECT the same as TMS?
No. ECT uses electric current to induce seizure activity, usually with sedation, while rTMS avoids most seizure activity and needs no anesthesia. [1]
Which type of brain stimulation works best?
There is no universal winner. In one large network meta-analysis for depression, some ECT forms had higher response than other active treatments, but estimates varied in precision. [4]
Are all brain stimulation devices approved?
No. Approval or clearance applies to a specific device and use; see device-specific approval.
Can I try these at home?
Home use is a regulated question that differs by product. See DIY stimulation risks and discuss any device with a clinician.
More details: evidence, limits and cautions
The details behind this page: cautions, limits of the evidence and where sources disagree. Open any note to read it.
Safety note
References
- National Institute of Mental Health. Brain Stimulation Therapies. Read 2026-10-22.
- U.S. Food and Drug Administration. PMA P230024: Summary of Safety and Effectiveness Data (Flow FL-100). Read 2026-10-22.
- Nabil Y, et al. Transcranial alternating current stimulation for major depressive disorder: An updated systematic review and meta-analysis of randomized trials with GRADE assessment. J Affect Disord. 2026. Read 2026-10-22.
- Mutz J, et al. Comparative efficacy and acceptability of non-surgical brain stimulation for the acute treatment of major depressive episodes in adults: systematic review and network meta-analysis. BMJ. 2019. Read 2026-10-22.