The relationship between mothering in infancy, childhood experience and adult mental health: results of the Brody prospective longitudinal study from birth to age 30.
This longitudinal study has followed seventy-six individuals from birth to age 30 using films of the mother-child interaction, psychoanalytically informed interviews of parents and children, and psychodiagnostic testing to assess how the quality of mothering a child receives in the first year of life contributes to his/her subsequent emotional well-being. The thirty-year follow-up of the now adult participants found that those who had received more effective care in infancy in terms of maternal empathy, consistency, control, thoughtfulness, affection and management of aggression had higher-level psychological defence mechanisms as adults than children receiving less effective nurturing--suggesting a process in which the children internalised their mothers' own defence mechanisms. Other measures at 30 years (Global Functioning, Erikson psychosocial attainment, mental representation of security of attachment to parents and presence or absence of a psychiatric diagnosis) did not achieve statistical significance. On the other hand, trauma after infancy and before age 18 provided the strongest correlation with adult outcome: consistent with the theory of the effect of cumulative trauma on psychic functioning, children experiencing two or more adverse circumstances had significantly lower levels of global functioning as adults than those spared multiple traumas. With case examples, the findings illustrate how the effect of pre-verbal experience attenuates over time, and how later influences overlie early life in the course of psychological structuralisation.