Figure 3
(A) VAN-window ERP activity for trials with low, mid, and high prestimulus alpha power. Alpha conditions were created by organizing trials into terciles according to ascending prestimulus alpha power as averaged within a specific spatiotemporal ROI. Cue-locked ERP raw traces for each prestimulus alpha condition are plotted (top panel) along with the topographic distribution for the difference wave derived from the low minus high alpha conditions (bottom panel). A Bayesian mixed-effect regression showed strong evidence that VAN-window ERP amplitudes were more negative for the low-power versus the high-power alpha conditions. This indicates that lower prestimulus alpha was associated with more negative VAN-window ERP amplitudes. (B) The left-side topo plots illustrate the ‘low-power minus high-power’ VAN-window ERP difference for trials when the cue appeared in the upper visual field (cue-up) and for trials when the cue appeared in the lower visual field (cue-down). Illustrated in the right-side bar plot, a Bayesian generalized mixed-effect regression showed no difference in amplitude between the ‘cue-up’ and ‘cue-down’ trials across three medial electrode sites.
