HF-rTMS and rPMS are associated with different acute cortical response profiles in stroke, with HF-rTMS showing reduced task-evoked hemodynamic responses and rPMS showing increased motor cortex activation, as measured by fNIRS.
Key Findings
Results
HF-rTMS reduced task-evoked oxyhemoglobin response magnitude in selected frontal regions of interest in stroke patients.
HF-rTMS was delivered at 5 Hz with 1500 pulses in a single session
Reductions in HbO RMS were observed in selected frontal ROIs
HF-rTMS also reduced RMSE (response dispersion) in the dorsolateral prefrontal cortex (DLPFC) and frontopolar area (FPA)
HF-rTMS showed an exploratory decrease in DLPFC-inferior frontal gyrus (IFG) functional connectivity
A descriptive negative laterality index tendency was observed following HF-rTMS
Results
rPMS increased task-evoked oxyhemoglobin response magnitude in the M1 region of interest, which comprised M1 channels from both hemispheres.
rPMS was delivered at 25 Hz with 1500 pulses in a single session
rPMS also increased FPA RMSE (response dispersion)
rPMS showed an exploratory increase in S1-IFG functional connectivity
A descriptive positive laterality index tendency was observed following rPMS
The M1 ROI included channels from both hemispheres
Results
The disease-duration-adjusted FPA RMSE Time × Group interaction was statistically significant, indicating differential effects of HF-rTMS versus rPMS on frontopolar area response dispersion.
F(1,54) = 15.595, p < 0.001, partial η² = 0.224
This interaction remained significant after exclusion of the participant with an extreme post-stroke duration
Disease duration was used as a covariate in this analysis
The effect size (partial η² = 0.224) indicates a large effect
Results
No functional connectivity differences remained statistically significant after false discovery rate correction.
FC analyses included region-to-region connectivity measures
Exploratory decreases in DLPFC-IFG FC were observed for HF-rTMS before correction
Exploratory increases in S1-IFG FC were observed for rPMS before correction
False discovery rate correction eliminated statistical significance of all FC findings
Methods
The study enrolled 57 stroke patients with unilateral stroke at varying post-stroke durations, using a pulse-count-matched design to directly compare HF-rTMS and rPMS.
57 patients with unilateral stroke were included
Patients were at varying post-stroke durations
Both interventions were matched at 1500 pulses per session
fNIRS monitored cortical hemodynamics during a motor task immediately before and after intervention
Outcome measures included HbO RMS, RMSE, laterality index, and region-to-region functional connectivity
Results
HF-rTMS and rPMS showed divergent laterality index tendencies, suggesting different effects on interhemispheric balance following stroke.
HF-rTMS was associated with a descriptive negative laterality index tendency
rPMS was associated with a descriptive positive laterality index tendency
These laterality findings were described as descriptive tendencies rather than statistically confirmed results
The divergent patterns suggest the two modalities may differentially affect the balance of cortical activity between hemispheres
What This Means
This research suggests that two types of magnetic stimulation therapies used after stroke — one targeting the brain directly (high-frequency repetitive transcranial magnetic stimulation, or HF-rTMS) and one targeting the body's peripheral nerves (repetitive peripheral magnetic stimulation, or rPMS) — produce distinctly different immediate effects on brain activity. Using a brain-imaging technique called functional near-infrared spectroscopy (fNIRS), the researchers monitored blood flow changes in the brains of 57 stroke patients while they performed a movement task, measuring these changes before and after a single session of either treatment. Both therapies delivered the same number of magnetic pulses (1500), allowing for a fair comparison.
The study found that HF-rTMS (applied directly over the brain) tended to reduce the intensity of brain activity in frontal regions and showed signs of calming certain brain network connections, while rPMS (applied to the body's peripheral nerves) tended to increase brain activity in the motor cortex — the region responsible for movement control — and appeared to boost connectivity in other network pathways. The most statistically robust finding was a significant difference between the two groups in how a frontal brain region called the frontopolar area responded to treatment, even after accounting for how long patients had been post-stroke.
This research matters because it provides objective brain-imaging evidence that these two commonly used rehabilitation approaches work through different mechanisms in the brain after stroke. Understanding these differences could eventually help clinicians choose the most appropriate stimulation approach for individual patients based on their specific brain activity patterns, though further research is needed to determine how these immediate brain changes relate to longer-term recovery outcomes.
Song Z, Wei K, Zeng H, Zhan X, Fan Q, Wang X, et al.. (2026). Neuromodulation effects of HF-rTMS and rPMS on stroke patients: an fNIRS study.. Journal of neural engineering. https://doi.org/10.1088/1741-2552/aea36a