Nonlinear Association Between N2 ERP Amplitudes and Dysregulated Behavior in Young Children

• In Event: 3-140 - Neural Correlates of Behavior Disorders in Early Childhood: Evidence From Multiple Neuroimaging Methods

Integrative Statement

The N2 event-related potential (ERP) component elicited during the no-go trials of a go/no-go task is thought to reflect response inhibition, a core deficit in dysregulated behavior. Studies have identified an association of N2 amplitudes with self-regulation and externalizing disorders (e.g., ADHD; Smith et al., 2004). However, an intriguing paradox has emerged. Meta-analyses have demonstrated that N2 amplitudes decrease with age (Hoyniak, 2017) and that smaller N2 amplitudes are associated with better performance on self-regulation tasks (Hoyniak & Petersen, under review). These findings suggest that smaller N2 amplitudes reflect more mature and efficient inhibitory processing. Alternatively, meta-analytic evidence has also demonstrated that smaller N2 amplitudes are associated with increased ADHD and conduct disorder (Hoyniak & Petersen, under review), suggesting that smaller N2 amplitudes may be a risk factor for externalizing disorders. Thus, there are seemingly paradoxical findings that leave open the question of whether smaller or larger N2 amplitudes are related to dysregulated behavior.

The present study tested one possible explanation for the apparent paradox: that the association between N2 amplitudes and dysregulated behavior is nonlinear. Participants included 127 children (56 girls) who were 2–3 years old (M = 3.21, SD = 0.42) who completed a go/no-go task while electroencephalography (EEG) data were collected. Some children had longitudinal EEG data, for a total of 201 observations. The children were instructed to push a button when a fish appeared on a computer screen (go trials), and not to push the button when a shark appeared on the screen (no-go trials). The task included 80 trials, 60 go trials and 20 no-go trials. ERPs generated were time-locked to presentation of the fish or the shark stimulus.

N2 amplitudes were calculated using a sequential temporo-spatial principal components analysis, which identified time frames and regions of electrodes that parsimoniously accounted for variability in the waveforms. Grand-averaged waveforms are in Figure 1. We focused on the component corresponding to the fronto-central electrode region during the timing of the second negative deflection (N2), an a priori region and time of interest. The PCA component reflecting the N2 had an average peak latency of 415ms (SD = 26).

Self-regulation was measured using three inhibitory control tasks that require children to inhibit dominant responses and respond with subdominant responses. The inhibitory control tasks included: Bird/Alligator (a variant of the Bear/Dragon go/no-go task), Shape Stroop, and Grass/Snow. ADHD symptoms were rated by secondary caregivers and parents on the Child Behavior Checklist.

N2 amplitudes showed a quadratic association with performance on Bear/Dragon (β = -.14, p = .012) and Shape Stroop (β = -.15, p = .054), but not Grass/Snow (β = -.09, p = .172). N2 amplitudes showed a quadratic association with secondary caregivers’ reports (β = .24, p = .041), but not parents’ reports (β = .05, p = .557), of ADHD symptoms. Quadratic associations are depicted in Figure 2.

Findings suggest that there may be an optimal level of inhibitory processing; too small or too large N2 amplitudes may be associated with dysregulated behavior.

Authors

• Isaac Petersen, University of Iowa, Department of Psychological and Brain Sciences
  Presenting Author

• Caroline Page Hoyniak, Indiana University - Bloomington
  Non-Presenting Author

• Angela D. Staples, Eastern Michigan University
  Non-Presenting Author

• John Bates, Indiana University - Bloomington
  Non-Presenting Author

• Dennis Lee Molfese, University of Nebraska - Lincoln
  Non-Presenting Author