Effects of Transcranial Pulse Stimulation of the Primary Motor Cortex on Motor Performance in Healthy Adults: A Randomized Crossover Pilot Study

Abstract

Aims: We aimed to investigate the behavioral aftereffects of a novel noninvasive brain stimulation technique—transcranial pulse stimulation (TPS)—applied over the right motor cortex (rM1) in healthy adults. Methods: Thirty-four healthy adults underwent a randomized, subject- and analyst- blind, crossover trial, receiving active TPS over the rM1 or control TPS over the vertex in two sessions 24 h apart. Motor performance was assessed using the Nine-Hole Peg Test (NHPT) and the Simple Reaction Time Task (SRTT) before, immediately after, and every 10 min for 40 min after each session. A linear mixed model and post hoc analyses were applied to evaluate the effects. Results: No significant interaction effect (stimulation condition × time) was found. The left-hand NHPT performance significantly improved from 10 min post-TPS onward in both conditions (ps ≤ 0.002). Conclusion: A single session of rM1-TPS does not yield significant improvements in motor dexterity compared to vertex-TPS. Future well-powered studies with a sham control condition and multiple stimulation sessions are needed to investigate the aftereffects using a combination of neurophysiological and neuroimaging approaches. Trial Registration: This study was registered in ClinicalTrial.gov in April 2024 (NCT06312930).