Fig 6. ERPs: Peak amplitudes.

Each diagram represents the absolute difference in the amplitudes of specific peaks (N2,P2,N2P2 amplitude) of one type of somatosensory-ERP (Laser-, Vibrotactile-, Cool-ERPs), recorded at a specific timepoint (T0,T2) or phase of the duty cycle (OFF,ON) under one experimental condition (sham, taVNS or cVNS). Within each diagram, individual values are shape-coded according to the experiment in which they were retrieved (circles for Experiment 1, triangles for Experiment 2, diamonds for Experiment 3). Grey boxes represent group statistics, with the central horizontal lines and top/bottom extremities indicating the means ± SD values. The Y axes represent the absolute difference (in μV) measured between two recordings of a specific peak. The X axes indicate which timepoints or phases of the duty cycle are compared on the related Y axes. There were no statistically significant results obtained.