The Neurophysiologic Impacts of Transcutaneous Vagus Nerve Stimulation on Inhibitory Control

BACKGROUND: As a promising noninvasive brain stimulation technique, transcutaneous vagus nerve stimulation (tVNS) is considered to positively modulate the inhibitory control (IC) process by activating the locus coeruleus‐norepinephrine pathway and increasing neurotransmitter release. However, the neuroplasticity regulation mechanisms underlying tVNS‐induced IC improvement remain unclear. OBJECTIVES: We explored the neuroplastic mechanisms of tVNS effects on IC by a multidimensional electroencephalogram (EEG) analysis framework, focusing on brain activity during both resting‐state and IC task‐state. MATERIALS AND METHODS: A total of 21 young male college students were recruited to undergo EEG recording using a counterbalanced and randomized within‐subjects crossover design. EEG data were collected before and after stimulation, and the participants were required to perform a two‐stage stop‐signal task during stimulation. RESULTS: No significant difference was observed between tVNS and sham‐tVNS (sham) in the behavioral performance of stop‐signal task or the N2 component. However, compared with the resting‐state EEG following sham, tVNS induced a decrease in delta and theta oscillations, and an increase in beta oscillations in fronto‐central region. In addition, tVNS strengthened the small‐world coefficient (Sigma). Meanwhile, compared with the task‐state EEG following sham, tVNS increased alpha oscillations and attenuated task‐state FC. CONCLUSIONS: These results suggested that tVNS positively modulates resting‐state brain activity. The data further indicated that tVNS can increase neural efficiency during IC‐state brain activity, as well as improve the information transmission efficiency of the IC‐state brain network, which provided empirical evidence supporting tVNS as an effective strategy for enhancing IC capabilities through neuroplasticity modulation.