Neural Noise- Transcranial static magnetic field stimulation (tSMS) of the primary motor cortex has been studied in essential tremor in a randomized pilot.1
- tSMS is a non-invasive neuromodulation modality that informs the toolkit for motor disorders.1
- The work was reported in Nature and is tier-1.1 1
Weekly enrichment (2026-07-20)
- The underlying primary study (npj Parkinson’s Disease, 2025; ClinicalTrials.gov NCT03780426) was a randomized, double-blind pilot testing acute tSMS over the primary motor cortex in 27 essential-tremor patients (mean age 66.9 ± 12.1 years), with 23 included in the final analysis.2
- Each patient received a single 30-min tSMS session over either the left (n = 13) or right (n = 14) hemisphere; postural tremor was measured by accelerometry and kinetic tremor by part B of the Clinical Rating Scale for Tremor (CRST).2
- Bayesian analysis found moderate evidence for a bilateral reduction of postural and rest tremor after unilateral tSMS, only anecdotal evidence for reduced kinetic tremor, and moderate evidence of no change in tremor frequency.2
- The effects were transient (largely subsiding within ~15 min post-stimulation); the authors conclude a single 30-min session is safe, may reduce tremor, and causally implicates M1 overactivity in ET pathophysiology, warranting larger trials.2
- Device details: a cylindrical NdFeB (neodymium) magnet ~45 mm diameter, 30 mm thick, ~360 g (MAG45r, Neurek SL, Toledo, Spain) applied with south polarity via a tSMS helmet, with an identical non-magnetic metal cylinder as sham.2
- Mechanistic context: the founding tSMS study (Oliviero et al., 2011) showed 10 min of tSMS reduced motor-cortex excitability by up to ~25% (TMS-elicited MEPs) for several minutes, an effect that was dose-dependent on field intensity, polarity-independent, and localized to intracortical rather than corticospinal/spinal networks.3
- Mechanistically, tSMS effects are attributed to magnetic-torque-induced changes in neuronal membrane morphology and voltage-gated ion-channel (Ca2+, Na+) function without inducing electric currents; NdFeB magnets reach roughly 0.1 T at ~2 cm cortical depth, and 30-min sessions can prolong the suppressive effect.45
- BCI/clinical implication: as a portable, low-cost, wearable-form neuromodulator, tSMS expands the non-invasive toolkit for motor disorders, though current ET evidence is confined to acute, single-session, small-sample pilot data.2