Developmental Trajectories of Delta–Beta EEG Coupling Across Infancy: The Influence of Infant Temperament and Maternal Anxiety Over Time

Coupling, or the correlation, between delta and beta EEG power may underly regulatory processes. Stronger, positive delta–beta coupling is associated with anxiety and fearful temperament, potentially tracking dysregulation. However, most studies have reported on cross-sectional investigations of delta–beta coupling in children. Thus, the normative development of delta–beta coupling remains poorly understood. Here, we leveraged a diverse sample (N = 165) of infants with assessments of EEG, negative affect, and maternal anxiety across 4, 8, 12, 18, and 24 months to model trajectories of delta–beta coupling and associations with infant and maternal traits over time. Multilevel models of delta (1–2.5 Hz) and beta (11–18 Hz) power indicated that delta–beta coupling increased from 8 to 24 months at the Frontal region but decreased over time at the Central and Parietal regions. Increasing negative affect over time (slope) was associated with steeper decreases in Parietal coupling. Higher maternal anxiety levels over time were associated with increasing trajectories of Parietal delta–beta coupling, but only for infants with decreasing negative affect trajectories. We show that delta–beta coupling trajectories are differentially modulated by infant temperament and anxiety levels in the infants’ proximal environment.