Anxiety and depression are highly prevalent in youth and can cause significant distress and functional impairment. The presence of maternal anxiety and depression are well-established risk factors for child internalizing psychopathology, yet the responsible mechanisms linking the two remain unclear.
We examined the potential mediating and moderating roles of EEG frontal alpha asymmetry (FAA) in the intergenerational transmission of internalizing symptoms in a longitudinal sample of N = 323 mother-child dyads. Self-report maternal internalizing symptoms were evaluated at child age 3 years and 5 years, child EEG at 5 years, and parent-report child internalizing symptoms at age 7 years. Mediation was evaluated via bootstrapped (N = 5,000) confidence intervals.
We found significant associations among maternal internalizing (anxiety, depressive) symptoms when their children were ages 3 and 5 years, child FAA at age 5 years, and child internalizing symptoms at age 7 years. There was a significant mediation effect, whereby greater maternal anxiety and depressive symptoms at age 3 years were significantly associated with FAA (greater relative right cortical activation) in children at age 5 years, which, in turn, was significantly associated with greater child internalizing symptoms at age 7 years (ps < .001). There was no moderating effect of FAA on the association between maternal internalizing symptoms at age 5 years and child internalizing symptoms at age 7 years.
Greater right frontal asymmetry may be a neurophysiological mechanism that mediates the intergenerational transmission of internalizing symptoms.

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