Infant frontal alpha asymmetry predicts social attention and transdiagnostic risk for emotional reactivity

Differences in Frontal Alpha Asymmetry (FAA), derived from the electroencephalogram (EEG), have been associated with approach-withdrawal behavior, although inconsistently. The current study examined how early patterns of FAA during the first 2 years of life relate to various socioemotional characteristics (at 2 years) and ultimately psychopathology symptoms (at 3 years).

Using a longitudinal prospective cohort design, 211 families were followed during the first two years of life. EEG data were obtained at 2-, 6-, 9-, 12-, and 24 months. Child socioemotional characteristics were assessed at 2 years using the Infant-Toddler Social and Emotional Assessment. Child psychopathology symptoms were assessed at 3 years using the Child Behavior Checklist (CBCL). Structural Equation Models were used for analyses.

Greater relative left frontal asymmetry at 12 months was associated with greater social attention (β = 0.39, p = 0.0006), empathy (β = 0.31, p = 0.01), and social approach (β = 0.33, p = 0.0038) at 2 years. FAA was not significantly associated with inhibition to novelty (i.e., withdrawal), although it did covary with other socioemotional characteristics. Only higher levels of social attention were significantly associated with subsequent psychopathology symptoms, specifically with lower levels of emotional reactivity (β = -0.29, p = 0.012). Social attention also predicted categorical symptoms including Attention-Deficit/Hyperactivity Disorder, Autism Spectrum Disorders, and Depression.

FAA lateralization at 12 months was linked to early social attention, empathy, and social approach at 2 years. However, only lower levels of social attention predicted higher emotional reactivity at 3 years. These findings highlight the importance of attentional processes (e.g., social attention), rather than behavioral differences (e.g., approach/withdrawal) for the link between FAA and psychopathology. Future research replicating these findings and on interventions addressing underlying attentional/sensory processing differences may be relevant to support the development of emotion regulation.