The Immediate Effects of Intermittent Theta Burst Stimulation of the Cerebellar Vermis on Cerebral Cortical Excitability During a Balance Task in Healthy Individuals: A Pilot Study.

This pilot study aimed to investigate the immediate effects of single-session intermittent theta-burst stimulation (iTBS) on the cerebellar vermis during a balance task, which could unveil the changes of cerebral cortical excitability in healthy individuals. A total of seven right-handed healthy subjects (26.86 ± 5.30 years) were included in this study. Each subject received single-session iTBS on cerebellar vermis in a sitting position. Before and after the intervention, all subjects were asked to repeat the balance task of standing on the left leg three times. Each task consisted of 15 s of standing and 20 s of resting. Real-time changes in cerebral cortex oxygen concentrations were monitored with functional near-infrared spectroscopy (fNIRS). During the task, changes in blood oxygen concentration were recorded and converted into the mean HbO for statistical analysis. After stimulation, the mean HbO in the left SMA ( = 0.029) and right SMA ( = 0.043) significantly increased compared with baseline. However, no significant changes of mean HbO were found in the bilateral dorsolateral prefrontal lobe ( > 0.05). Single-session iTBS on the cerebellar vermis in healthy adults can increase the excitability of the cerebral cortex in the bilateral supplementary motor areas during balance tasks. [www.ClinicalTrials.gov], identifier [ChiCTR2100048915].