Effects of Peripheral Magnetic Stimulation on Cortical Excitability in Healthy Individuals

Phase 1

Recruiting

• Conditions: Healthy Individuals

• Registration Number: NCT07025759
• Lead Sponsor: Universidade Federal de Pernambuco

Brief Summary

This study investigates the immediate effects of different parameters (frequency, intensity, and pulse number) of peripheral magnetic stimulation (rPMS) on cortical excitability in healthy individuals. Using a randomized, double-blind crossover design, the research aims to identify optimal stimulation protocols for modulating neural activity. Outcomes include measurements of motor-evoked potentials (MEPs), intracortical inhibition (ICI), and facilitation (ICF). Findings may enhance non-invasive therapeutic strategies for neurological disorders.

Detailed Description

This clinical trial is a crossover trial comparing 9 single-session rPMS protocols over the extensor carpi radialis muscle, testing three frequencies (1Hz, 10Hz, 25Hz), intensities (90%, 100%, 110% of resting motor threshold) across sequential phases.

Participants: Healthy adults (18-40 years) undergo pre-/post-intervention assessments: cortical (MEPs, ICI/ICF) excitability.

Design: Crossover, double-blind.

Analysis: ANOVA or Friedman tests (SPSS v20.0; α=0.05).

Significance: Clarifies parameter-specific neuromodulatory effects, guiding future rehabilitation protocols for neurological conditions.

Ethics: Approved by Federal University of Pernambuco's ethics committee (Resolution 466/12). Data stored securely for 5 years.

Study Timeline

• Study Start: 2022-10-01
• Status Verified: 2025-06
• Study First Submitted: 2025-06-09
• Study First Submitted QC: 2025-06-16
• Last Update Submitted: 2025-06-16
• Study First Posted: 2025-06-17
• Last Update Posted: 2025-06-17
• Primary Completion: 2025-09
• Study Completion: 2025-10

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 18

Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Primary Outcome Measures

Name	Time	Method
Cortical excitabilty	Baseline (T0), immediately post-stimulation (T1), 15 minutes (T2), and 30 minutes (T3) post-stimulation.	Cortical excitability will be assessed through motor-evoked potentials (MEPs) elicited by single-pulse transcranial magnetic stimulation (TMS) over the primary motor cortex (M1), targeting the first dorsal interosseous (FDI) representation area. The hotspot will be determined as the site producing the largest MEP amplitude at the lowest intensity, with stimulation delivered at 100% of the resting motor threshold (RMT). Additionally, paired-pulse TMS protocols will evaluate intracortical inhibition (ICI) and facilitation (ICF) using conditioning stimuli at 80% RMT (3 ms interstimulus interval for ICI, 10 ms for ICF) and test stimuli at 120% RMT. MEP amplitudes will be recorded via surface electromyography (EMG) from the FDI muscle using bipolar electrode placement, with signals sampled at 20,000 Hz (bandpass 5-10,000 Hz) to capture corticospinal excitability changes across timepoints (baseline, post-intervention, and follow-ups).

Trial Locations

Locations (1)

Universidade Federal de Pernambuco; 🇧🇷 Recife, Pernambuco, Brazil