Neural Correlates of Response Inhibition in Early Childhood: Evidence From a Go/No-Go Task

ABSTRACT

We examined the neural correlates underlying response inhibition in early childhood. Five-year-old children completed a Go/No-go task with or without time pressure (Fast vs. Slow condition) while scalp EEG was recorded. On No-go trials where inhibition was required, the left frontal N2 and posterior P3 were enhanced relative to Go trials. Time pressure was detrimental to behavioral performance and modulated the early-occurring P1 component. The topography of ERPs related to response inhibition differed from patterns typically seen in adults, and may indicate a compensatory mechanism to make up for immature inhibition networks in children.

Notes

1. To make the rules of the task easy for children to understand, two different categories of stimuli (fish, sharks) were used on Go and No-go trials. However, this may have introduced differences between the Go and No-go trials, for example in stimulus salience. To investigate whether the fish and shark stimuli differed in salience, we administered a target detection task to an adult sample (n = 6). This study identified two stimuli as outliers: one fish was .53 standard deviations above the mean in salience and one shark was .52 standard deviations below the mean. We re-analyzed the behavioral data using repeated measures ANOVA excluding these two stimuli. For accuracy, there was a main effect of speed condition (F(1,29) = 12.33, p < .01, η² = .298) and an interaction between speed condition and trial type (F(1, 29) = 15.22, p < .01, η² = .344). For RT, there were main effects of speed condition (F(1, 29) = 68.0, p < .001, η² = .701) and trial type (F(1, 29) = 1381.48, p < .001, η² = .979). As the pattern of findings did not differ from those including the complete stimulus set, the latter are reported in the Results section.

2. Because we expected children in the Fast condition to make more errors, we had them complete a greater number of trials. To test whether this difference in procedure affected study findings, we analyzed the behavioral data using repeated measures ANOVA excluding the last block of trials from children in the Fast condition so that both conditions contributed an equal number of trials. For accuracy, there was a main effect of speed condition (F(1,29) = 17.25, p < .001, η² = .373) and an interaction between speed condition and trial type (F(1, 29) = 13.53, p < .01, η² = .318). For RT, there were main effects of speed condition (F(1, 29) = 17.94, p < .001, η² = .382) and trial type (F(1, 29) = 33.59, p < .001, η² = .537). As the pattern of findings did not differ from those including the complete stimulus set, the latter are reported in the Results section.