Evidence suggests that maternal care constitutes a protective factor for psychopathology which may be conditional on the level of family adversity. Given that psychopathology is frequently linked with social deficits and the amygdala with social functioning, we investigated the impact of early maternal care on amygdala function under high vs low familial risk for psychopathology. Amygdala activity and habituation during an emotional face-matching paradigm was analyzed in participants of an epidemiological cohort study followed since birth (n = 172, 25 years). Early mother-infant interaction was assessed during a standardized nursing and play setting at the age of 3 months. Information on familial risk during the offspring's childhood and on the participants' lifetime psychopathology was obtained with diagnostic interviews. An interaction between maternal stimulation and familial risk was found on amygdala habituation but not on activation, with higher maternal stimulation predicting stronger amygdala habituation in the familial risk group only. Furthermore, amygdala habituation correlated inversely with Attention Deficit Hyperactivity Disorder (ADHD) diagnoses. The findings underline the long-term importance of early maternal care on the offspring's socioemotional neurodevelopment and of interventions targeting maternal sensitivity early in life, particularly by increasing maternal interactive behavior in those with familial risk.

Reward processing is altered in various psychopathologies and has been shown to be susceptible to genetic and environmental influences. Here, we examined whether maternal care may buffer familial risk for psychiatric disorders in terms of reward processing. Functional magnetic resonance imaging during a monetary incentive delay task was acquired in participants of an epidemiological cohort study followed since birth (N = 172, 25 years). Early maternal stimulation was assessed during a standardized nursing/playing setting at the age of 3 months. Parental psychiatric disorders (familial risk) during childhood and the participants' previous psychopathology were assessed by diagnostic interview. With high familial risk, higher maternal stimulation was related to increasing activation in the caudate head, the supplementary motor area, the cingulum and the middle frontal gyrus during reward anticipation, with the opposite pattern found in individuals with no familial risk. In contrast, higher maternal stimulation was associated with decreasing caudate head activity during reward delivery and reduced levels of attention deficit hyperactivity disorder (ADHD) in the high-risk group. Decreased caudate head activity during reward anticipation and increased activity during delivery were linked to ADHD. These findings provide evidence of a long-term association of early maternal stimulation on both adult neurobiological systems of reward underlying externalizing behavior and ADHD during development.