Kilohertz Transcranial Magnetic Perturbation (kTMP) for Upper Extremity Motor Recovery After Stroke: A Nonrandomized Pilot Trial

Upper-limb scores were stable before treatment and improved during four weeks of combined kTMP and motor practice. The seven-person, unblinded study cannot separate the effects of stimulation, practice, expectation or chance, so a randomized trial is needed.

Merrick CM, Dai F, Singh S, O'Kidhain I, Reber P, Luu C, Peterchev AV, Sheltraw D, Ivry RB, Labruna L, Ganguly K.
medRxiv (preprint) · Publication date: 2026-10-07
Added to site: 2026-10-11
DOI: 10.64898/2026.10.05.26364594

Preprint posted October 7, 2026. Added to Neurofeedback.com October 11, 2026 after full-text review; not peer reviewed.

Modalities

Kilohertz transcranial magnetic perturbation, Motor training

Clinical focus

Chronic stroke, Upper-extremity rehabilitation

Population

Adults with chronic stroke and upper-extremity motor deficits

Sample

Seven participants; six completed the four-week follow-up

Intervention / method

Three sessions per week for four weeks of investigational subthreshold kTMP paired with upper-extremity motor tasks

Comparator

Within-person four-week standard-care baseline; no sham or parallel control group

Clinician summary

Mean FMA-UE change was +7.00 points from pre-intervention baseline (95% CI 5.31 to 8.69; multiplicity-adjusted p=0.047), and six of seven participants reached the cited six-point threshold. SPARC movement smoothness improved after one week and at week four. No device-related adverse events were reported and mean sensation ratings were below 0.5 on a 0 to 10 scale.

How to interpret the findings

This is a non-peer-reviewed, single-arm, open-label pilot with seven participants, no sham condition and unblinded FMA-UE assessment. Motor training and placebo effects cannot be separated from stimulation, one participant missed follow-up, and four-week durability is short. The findings do not establish efficacy.

Equipment and disclosures

Investigational kTMP technology was used. Magnetic Tides Inc. holds related patents, and several authors reported employment or equity; this record is not a product endorsement or BrainMaster attribution.

Supported by the NIH Common Fund and Weill Neurohub. Three authors were Magnetic Tides employees, and seven authors reported company equity; Magnetic Tides holds patents related to kTMP. Preprint findings have not undergone journal peer review.

Related evidence

Compare findings from the same clinical area, including mixed results.

• Neurofeedback-Guided Motor Imagery in Chronic Stroke: A Case Series on Upper-Limb Recovery, Cortical Activation, and Brain Symmetry. · Positive with limitations