There was only a trend towards significance for a negative correlation between AGE and mean delta source activity in the left medial superior frontal gyrus (lmSFG, p = 0.06) and left occipitotemporal junction (lOTJ, p = 0.07).
Mean source wave form resting-state data revealed only a statistical trend for an age-related decrease in slow wave activity, which was, however, in line with data reported by Fehr [ 20 ], who also reported a decrease in delta source activity (Minimum-Norm, L2) but also reported an increase in higher-frequency bands.