Posterior brain ERP patterns related to the go/no-go task in children

Event-related potentials (ERPs) and performance correlates of inhibition of responses to no-go stimuli were investigated in 6-12-year-old children and young adults. The percent of correct responses to go stimuli was high and similar in both groups-, the percent of false alarm errors to no-go was significantly higher in children. Effective inhibition of responses to no-go stimuli was elucidated by a negative component of ERPs, the frontal-central N2, with peak latency 230-430 ms after stimulus onset. In adults, N2 was larger to no-go than to go stimuli, regardless of stimulus frequency. This effect was more prominent in tasks with high (25% no-gos and 75% gos), than with low (75% no-gos and 25% gos) inhibitory demand. In children, the parietal N2 was generally larger to rare than to frequent stimuli, and it was more specifically related to inhibition. The analysis of the relationship of no-go N2 to the inhibitory content of stimuli, probability of stimuli, and the contextual task difficulty suggests that child/adult differences in behavioral responses and ERPs may be related to both the immaturity of the fronto-parietal cortical-cortical network and to different task strategies.