Neurophysiological correlates of taVNS-mediated cognitive enhancement

This study aims to investigate the neural mechanisms underlying cognitive enhancement through transcutaneous auricular vagus nerve stimulation (taVNS) by analyzing Stroop task performance and electroencephalography (EEG) data.

Twenty-three healthy adults (12 males; aged 19-40) were randomly assigned to either the taVNS or sham group. The Stroop task was administered in three sessions, with taVNS (3 Hz, 0.5 mA for 10 min) applied between sessions. EEG data were collected before and after the experiment, as well as during the Stroop task, for further analysis.

The taVNS group showed higher accuracy than the sham group under the incongruent condition in Session 3 (p < .05), consistent with differences in signal detection metrics, suggesting changes in decision processes. Across sessions, beta-band power increased during task performance in the sham group, whereas this increase was attenuated in the taVNS group. This effect was most pronounced in the high beta range (20-30 Hz) at the Fp1 channel (FDR-corrected q < 0.05).

taVNS attenuated the task-related escalation in high beta-band power typically observed during sustained Stroop performance, thereby mitigating cognitive demand and enhancing response accuracy.

These results position taVNS as a promising non-invasive intervention for strengthening cognitive control in healthy individuals.