Interoception sensitivity in the parental brain during the first months of parenting modulates children's somatic symptoms six years later: The role of oxytocin.

Interoception, the perception and interpretation of one's own bodily signals, is a key aspect of human caregiving that impacts infant health and well-being across life. Interoception relies on limbic structures, mainly the amygdala, and the agranular visceromotor cortex, particularly the anterior insula (AI), that integrate with the oxytocin (OT) system to support interoceptive sensitivity. Here, we used functional magnetic resonance imaging (fMRI) to examine whether interoception sensitivity in the parent's brain during the first months of parenting combines with sensitive parenting and OT-system functionality to predict children's somatic symptoms six years later. We followed 45 primary-caregiving first-time mothers and fathers and their infants across the first six years of parenting. In infancy (Time 1), parents' brain response to infant stimuli was imaged, salivary OT measured, and parent-infant interactions coded for parent sensitivity. In preschool (Time 2), parent and child's OT and parent sensitivity were measured again. At six years (Time 3), parents reported on children's somatic symptoms. Greater activation of the parent's AI bilaterally when his/her child was an infant predicted lower child somatic problems at six years. Parent sensitivity partially mediated the links between parental AI activation and child somatic symptoms. In addition, greater parental bilateral amygdala activity predicted higher child OT levels at 3 years and parental OT moderated the relations between preschoolers' OT and later somatic symptoms. Our findings chart two independent cross-generational pathways from interoception sensitivity in the parent's brain and child somatization. The first defines an evolutionary-ancient path including the amygdala and the OT system that support mammalian attention to arousal modulations in response to social cues; the second, via the AI, implicates higher-order interoceptive representations of bodily responses and affective states that underpins human embodiment.