Related Experiment Video
Updated: Aug 31, 2026
Combined Transcranial Magnetic Stimulation and Electroencephalography of the Dorsolateral Prefrontal Cortex
Published on: August 17, 2018
Inter- and intra-individual variability of paired-pulse curves with transcranial magnetic stimulation (TMS)
Fumiko Maeda1, Massimo Gangitano, Mark Thall
1Laboratory for Magnetic Brain Stimulation, Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Kirstein Building KS 454, 330 Brookline Avenue, Boston MA, USA.
Objectives:
Previous studies have evaluated the variability of motor thresholds (MTs) and amplitude of motor-evoked potentials (MEPs) to transcranial magnetic stimulation (TMS) within and across individuals. Here we evaluate the reproducibility and inter-hemispheric variability of measures of cortical excitability using the 'conventional' paired-pulse (PP) TMS technique.
Methods:
We studied PP curves of the left and right hemisphere in 10 healthy subjects on two separate days 2 weeks apart. The inter-stimulus intervals studied were 1, 3, 6, 8, 10 and 12 ms with the conditioning stimulus being 80% of the resting MT, and a single test stimulus producing MEPs of approximately 0.8 mV peak-to-peak amplitude.
Results:
As a group, the PP curves of the left and right hemispheres, and of Day 1 and Day 2 were not significantly different. The intracortical inhibition (ICI), but not the intracortical facilitation, showed a good correlation across days within the individuals.
Conclusions:
Cortical excitability, particularly ICI, measured by PP TMS shows no inter-hemispheric asymmetry and is reproducible within individuals.
More Related Videos
09:52Measuring and Manipulating Functionally Specific Neural Pathways in the Human Motor System with Transcranial Magnetic Stimulation
Published on: February 23, 2020
12:13Assessing Primary Motor Cortex Excitability and Excitability Modulation by Pairing Transcranial Magnetic Stimulation with Electromyography
Published on: October 7, 2025