Menstrual Cycle TMS Plasticity Pilot

NCT07180654 | Recruiting FDA Device

• 1 other identifier: 858764
• Study Type: observational
• Target: 100
• Locations: 1 country
• Sites: 1

Brief Summary

Aim 1: Assess how menstrual cycle phase affects motor cortex plasticity in females. Aim 2: Compare motor cortex plasticity between males and females across the same time points, identifying potential sex differences in TMS response. Aim 3: Examine associations between serum hormone levels and TMS-induced plasticity within and between sexes.

Conditions

Cortical Activation

Keywords

transcranial magnetic stimulation; cortical excitability; hormones

Outcome Measures

Primary Outcomes (2)

• Single-pulse TMS

  Single-pulse TMS: Cortical excitability curves will be measured before and after a single 1800-pulse train of iTBS. Motor Evoked Potentials (MEPs) will be recorded from the right FDI muscle at 7 distinct intensities ranging from -20% to + 40% of MT. Single pulses will be delivered once every 10±3 seconds to the left motor cortex at random intensities in the above range to avoid habituation across pulses. Across the session, a total of 70 pulses will be delivered before and after iTBS, 10 at each intensity.

  Will be collected during 3 visits over the course of a 2 month timeframe during different phases of the menstrual cycle (in females).

• Paired pulse stimulation

  Paired-pulse stimulation: Subjects will undergo paired-pulse stimulation to measure both intracortical inhibition and intracortical facilitation. For intracortical inhibition, subjects will receive a conditioning pulse at 80% MT 4 seconds before the test pulse at 120% MT. For intracortical facilitation, subjects will receive a conditioning pulse at 120% MT 15s before the test pulse at 120% MT. Across the session, a total of 60 paired pulses will be delivered before and after iTBS, 30 at each ISI.

  Will be collected during 3 visits over the course of a 2 month timeframe during different phases of the menstrual cycle (in females).

Study Arms (1)

Volunteers

Single group design

Device: transcranial magnetic stimulation

Interventions

transcranial magnetic stimulation DEVICE

Subjects will receive a series of 60 10s trains that will be presented over the course of the \~3.5 min session. Each train will consist of 2 s of stimulation with an 8 s ITI. During the 2 s of stimulation, 10, 50 Hz bursts will be repeated at intervals of 200 ms (5 Hz). iTBS will be administered at 100% of the motor threshold (MT).

Volunteers

Eligibility Criteria

• Age: 20 Years - 40 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)
• Sampling Method: Non-Probability Sample

Study Population

Participants will be recruited from the community in the Philadelphia Metro Area.

You may qualify if:

• Able to give their consent
• If female, must have menstrual cycles of normal frequency, regularity, and duration.

You may not qualify if:

• Non-English speaking
• Any medical condition that increases risk for TMS
• History of seizure
• History of epilepsy
• Increased risk of seizure for any reason

Sponsors & Collaborators

• University of Pennsylvania: lead

Study Sites (1)

University of Pennsylvania

Philadelphia, Pennsylvania, 19104, United States

RECRUITING

Biospecimen

Retention: SAMPLES WITHOUT DNA

Participants may be asked to provide blood samples. This analysis may measure serum estradiol, progesterone, testosterone, luteinizing hormone, and/or follicle-stimulating hormone. No more than 10 mL of blood may be collected at each visit. Blood will be collected at Penn.

MeSH Terms

Interventions

Transcranial Magnetic Stimulation

Intervention Hierarchy (Ancestors)

Magnetic Field Therapy; Therapeutics

Study Officials

• Nicholas Balderston, PhD

  University of Pennsylvania

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Nicholas Balderston, PhD

CONTACT

12157463058; nicholas.balderston@pennmedicine.upenn.edu

Study Design

• Study Type: observational
• Observational Model: OTHER
• Time Perspective: CROSS SECTIONAL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: September 2, 2025
• First Posted: September 18, 2025
• Study Start: December 15, 2025
• Primary Completion (Estimated): October 31, 2028
• Study Completion (Estimated): October 31, 2028
• Last Updated: January 9, 2026

Record last verified: 2026-01

Locations

US (1)