Fig. 3: Neural results.
From: Non-invasive peripheral nerve stimulation selectively enhances speech category learning in adults
a Top. Autoregression procedure used to remove tVNS pulse artifacts from the EEG signal. Center. Baseline and sub-threshold vagal evoked potentials (M and SEM) for participants receiving stimulation. The three significant evoked potentials are denoted as N1, P1, and N2. Bottom: inverted-U relationship between tVNS intensity and peak magnitude in the tVNS pulse-evoked response. The bars denote individual pulse-evoked magnitudes averaged for each intensity range (low, intermediate, and high intensities). b Stimulus-response correlation coefficients (FFR quality) for each participant, group, and tone before (x-axis) and after (y-axis) the training session. The panel shows a high degree of individual variability in FFR quality within each group (scatter plots) and no group differences in FFR quality before and after the training session (box plots). c Stimulus and neural (FFR) pitch by group (M and SEM) before and after the tVNS session.
