We did observe uncorrected significant effects for ERSP. Owing to the developmental thrust of this report, that the fine-grained decomposition of the data was quite restrictive in terms of statistical power, and that our analyses might guide future work by other investigators, we proceeded to exploratory analysis of our ERSP omnibus effects. ERSP analysis suggested that rather than the 4-8 Hz theta band typically applied in adult studies, a smaller frequency range (5-6.5 Hz) may capture the aspect of feedback processing corresponding temporally to the FRN. Consistent with other studies (Cavanagh, Figueroa, Cohen, & Frank, 2012; Cavanagh, Zambrano-Vazquez, et al., 2012) we observed a burst of theta activity coinciding with the time window of the FRN (200-300 ms). However, we also observed a second theta burst overlapping with the full theta range (4-8 Hz) at the end of the frequency range we examined. This process was observed up to the end of our temporal window (500-550 ms). Future studies might sample further into the post feedback period. We chose not to because of movement artifact present in the larger temporal window.
