Attentional demands do affect amplitudes of N1 and N2 in the sensory gating paradigm in neurotypical adults and children

Abstract

Past research has shown that N1 and N2 ERP components may be related to attention; however, few studies have measured N1 and N2 amplitudes when attention was manipulated. In this study, two ERP sensory gating paradigms were used in which attention was manipulated by requiring participants either to focus their attention on the auditory stimuli (FA) or to watch a movie that distracted them from the auditory stimuli (SGM). To examine the relationship of N1 and N2 amplitudes to performance on three types of attention (selective, sustained, and control/switch) all participants completed the Test of Everyday Attention for Children (TEA-Ch). Participants were 23 healthy adults aged 20-30 and 20 typically developing children aged 6-10. Across both groups, N1 amplitude was significantly larger for the FA compared to the SGM paradigm, F(1, 36) = 40.62, p < .001, and for the first click compared to the second, F(1, 36) = 40.62, p < .001. Adults showed larger N1 amplitudes compared to children and group main effect approached but did not reach significance, F(1,36) = 3.211, p = .082. Across both groups, N2 amplitude showed a trend for being larger in the SGM compared to the FA paradigm, F(1, 23) = 3.91, p = .06, and the first click was significantly larger than the second, F(1, 23) = 22.38, p < .001. Adults showed a trend for larger N2 amplitudes compared to children although group main effect did not reach significance, F(1,23) = 1.841, p = .188. For N2, significant interactions for paradigm x group, F(1, 23) = 4.12, p = .05, and click x group, F(1, 23) = 5.21, p = .03 were found. Separate regression analyses controlling for group membership revealed that subtest scores from all subsystems on the TEA-Ch were significant predictors of N1 amplitude for click 2 in the FA paradigm only; selective attention and control/switch attention subtest scores were the strongest predictors. Sustained attention and control/switch attention subtest scores of the TEA-Ch significantly predicted N2 amplitudes for click 1 in the FA paradigm only. The results suggest that N1 amplitude increases when attention is directed towards the task for adults and children alike. Alternatively, N2 amplitude shows a trend for increased amplitude when attention is directed away from the stimuli and children respond differently than adults. N1 has shown that it may represent a more global type of attention while N2 may be related to an ability to dismiss information.