Using a similar auditory event-related potential paradigm in both rats and humans we investigated the energy and phase variability of EROs. No significant changes were found in measures of ERO energy between the frequent and infrequent tones or between the active and passive tasks in periadolescent humans. Neuronal synchrony as indexed by PLI and PDLI was significantly higher to the infrequent (target) tone as compared to the frequent (non-target) tone in all brain sites in all of the ROI time frequency intervals. There was a smaller but significant increase in PLI but not PDLI as a function of “active” task requirements in periadolescent humans. Developmental differences consisting of significantly higher ERO energy in all frequency ranges (delta, theta, alpha, beta) in all three electrode sites (FZ, CZ, PZ), in the periadolescent humans as compared to the adults and in periadolescent rats in all frequencies in PCTX and all but beta in FCTX as compared to adult rats. Periadolescent humans were found to have significantly lower synchrony than adults as indexed by lower PLI levels in the delta and theta frequency
