Performance and ERP components in the equiprobable go/no-go task: Inhibition in children

The equiprobable go/no-go task lacks the dominant go imperative found in the usual go/no-go task, and hence we previously regarded it as involving little inhibition. However, children have relative difficulty with this task, and demonstrate large frontal no-go N2s. We investigated whether this child N2 plays an inhibitory role, using performance measures to illuminate the link between N2 and inhibition. Forty children aged 8 to 13 were presented with four stimulus blocks each containing 75 go and 75 no-go tone stimuli in random order. A temporal PCA with unrestricted varimax rotation quantified the mean go and no-go ERP component amplitudes. Most identified components were differentially enhanced to go or no-go as in adults, supporting a previously proposed differential processing schema. Between subjects, larger frontocentral no-go N2bs were associated with fewer commission errors. Hence, the no-go N2b in this paradigm can be interpreted as an individual marker of inhibition in children.