Are There Biological Programming Effects for Psychological Development? Findings From a Study of Romanian Adoptees

Neuropeptides and non-human primate social deficits associated with pathogenic rearing experience

There is a persuasive evidence that autism is highly heritable and likely to be substantially determined by polygenic mechanisms. Nevertheless, some intriguing findings in children raised in conditions of extreme social deprivation suggest that an autistic-like syndrome may occur as a consequence of environmental conditions. A particularly close model of this human syndrome has been studied in rhesus monkeys for almost half a century. Monkeys reared in pathogenic rearing conditions manifest considerable deficits in social interaction and increased self-directed behaviors. We have been interested in the possibility that disruptions in normal social development in non-human primates might be expressed in neuropeptide systems which have emerged in rodent studies as important candidates for a unique social biology. In recent studies, we have described persistently reduced CSF OT levels in male rhesus monkeys with significant social deficits. We also found that OT levels were positively related to the expression of affiliative social behaviors. Alterations were also detected in both CRH and AVP receptor binding patterns in limbic structures likely to influence social and emotional development. Taken together, these data suggest that abnormal rearing influences the development of brain systems critical to normal social and emotional competence in rhesus monkeys and may contribute to the development of autistic-like symptomatology associated with pathogenic rearing histories.

A comparison of the electroencephalogram between institutionalized and community children in Romania

Electroencephalographic (EEG) data were collected from a sample of institutionalized infants and young children in Bucharest, Romania, and were compared with EEG data from age-matched children from the local community who had never been institutionalized and who were living with their families in the Bucharest area. Compared with the never-institutionalized group, the institutionalized group showed a pattern of increased low-frequency (theta) power in posterior scalp regions and decreased high-frequency (alpha and beta) power, particularly at frontal and temporal electrode sites. This finding is consistent with EEG studies of children facing environmental adversity and children with learning disorders. The institutionalized group also showed less marked hemispheric EEG asymmetries than the never-institutionalized group, particularly in the temporal region. The results are discussed in the context of two models: that the pattern of EEG in the institutionalized children reflects a maturational lag in nervous system development, or that it reflects tonic cortical hypoactivation.

Environmentally mediated risks for psychopathology: research strategies and findings

OBJECTIVE

To consider the research design requirements needed to provide a rigorous test of environmental mediation hypotheses and to summarize the main findings from research using such designs.

METHOD

Selective review of empirical evidence dealing with psychopathology.

RESULTS

There is robust evidence of environmentally mediated risks for psychopathology. There are major individual differences in people's responses to risk experiences. Effects are often dependent on genetic susceptibility (operating through gene-environment interactions).

CONCLUSIONS

Many of the risks deriving from adverse experiences are reliant on nature-nurture interplay, and one of the main research needs concerns the diverse effects of the environment on the organism.

Adoption and Cognitive Development: A Meta-Analytic Comparison of Adopted and Nonadopted Children's IQ and School Performance

This meta-analysis of 62 studies (N=17,767 adopted children) examined whether the cognitive development of adopted children differed from that of (a) children who remained in institutional care or in the birth family and (b) their current (environmental) nonadopted siblings or peers. Adopted children scored higher on IQ tests than their nonadopted siblings or peers who stayed behind, and their school performance was better. Adopted children did not differ from their nonadopted environmental peers or siblings in IQ, but their school performance and language abilities lagged behind, and more adopted children developed learning problems. Taken together, the meta-analyses document the positive impact of adoption on the children's cognitive development and their remarkably normal cognitive competence but delayed school performance.

Maternal antenatal anxiety and behavioural/emotional problems in children: a test of a programming hypothesis

BACKGROUND

Previous animal investigations link antenatal stress with a range of persistent behavioural abnormalities in the offspring. The current study examined if the effect was also found in humans through middle childhood.

METHODS

The current study is based on the Avon Longitudinal Study of Parents and Children (ALSPAC), a prospective, community-based study that has followed a cohort of women from pregnancy. Self-report measures of maternal anxiety and depression were assessed at repeated intervals in pregnancy and the postnatal period. Children's behavioural/emotional problems were assessed by parent report at age 47 and 81 months. Information on obstetric and psychosocial factors was obtained at several points in pregnancy and the postnatal period.

RESULTS

Children whose mothers experienced high levels of anxiety in late pregnancy exhibited higher rates of behavioural/emotional problems at 81 months of age after controlling for obstetric risks, psychosocial disadvantage, and postnatal anxiety and depression (for girls, OR = 1.91, 95%CI = 1.26-2.89; for boys, OR = 2.16, 95%CI = 1.41-3.30). Furthermore, the effect at 81 months was comparable to what was previously obtained at 47 months, suggesting the kind of persistent effect proposed in the animal literature.

CONCLUSIONS

There is evidence that antenatal stress/anxiety has a programming effect on the fetus which lasts at least until middle childhood.