Intergenerational Transmission of Frontal Alpha Asymmetry Among Mother–Infant Dyads

Abstract

BackgroundFrontal alpha asymmetry (FAA) is a well-established neurobiological indicator of depression risk. Reduced FAA relates to current and remitted depression in adults and is seen in offspring of mothers with depression as young as 3 months of age, suggesting a potentially transmittable mechanism of depression risk. It is unclear, however, whether direct familial associations exist for FAA. To address this gap, we evaluated the intergenerational transmission of FAA in a nonclinical cohort of mother–infant dyads. MethodsMothers and their 12-month-old infants (n = 34 dyads) completed parallel resting-state tasks while electroencephalography was recorded. We measured FAA across a range of putative frequency bands and calculated its reliability in mothers and infants. Finally, we evaluated the heritability of FAA based on the parent–offspring correlation. ResultsMother and infant FAA convergence was strongest in the high alpha range for mothers (11–13 Hz) and broad alpha range for infants (6–9 Hz). Mother high FAA exhibited excellent split-half reliability (rSB = .99) and internal consistency after 80 seconds (α = .90); infant FAA exhibited good split-half reliability (rSB = .81) and fair internal consistency after 70 seconds (α = .74). Mother–infant FAA were moderately correlated (r = .41), which indicates narrow-sense heritability of up to 82%. ConclusionsFAA can be assessed reliably and relatively quickly in both adults and infants. There is a robust association of FAA between mothers and their infants, supporting intergenerational transmission. This finding is consistent with the possibility that reduced FAA may directly confer depression risk at the individual-family level.