A lack of nurturing may cause the brains of children raised in deprived environments to adapt in ways that make it difficult for the children to develop selective relationships with adoptive parents, suggests a recent study in Developmental Psychology (Vol. 40, No. 1).
The study's data come from an ongoing longitudinal study led by researchers Michael Rutter, MD, and Thomas G. O'Connor, PhD, of the Institute of Psychiatry in London. They are following two groups of children adopted between 1990 and 1992:
* 144 children raised in physically and socially depriving Romanian orphanages and then adopted by families in the United Kingdom (U.K.) at 6 to 42 months old.
* 52 children born in the U.K. and adopted by families there before they were 6 months old.
The Developmental paper includes assessments of the children when they were adopted, and at 4 and 6 years old. The researchers found that, at adoption, the Romanian children were substantially behind their U.K.-born peers in cognition, nutrition, weight and other developmental measures. However, at the follow-up assessments, the children showed remarkable progress in catching up with their peers. For example, by age 6, the Romanian group's mean cognition score--comprising measures of verbal, quantitative, perceptual and memory functioning--was close to that of the U.K.-born adoptees. Moreover, several of the Romanian-born children scored quite high on the cognition measures.
Nonetheless, the Romanian children were still substantially more likely than the U.K. adoptees to have cognitive deficits and problems in attachment relationships with their parents. For example, parents reported that the children were more likely to readily go off with a stranger. Further analysis showed that the Romanian children with low cognition were more likely to have been malnourished before adoption and, even at 6 years, had smaller head circumferences--an indication of less brain growth. The researchers also found that the children were more likely to have attachment problems the longer they were in a Romanian institution: 16 percent of Romanian children adopted before they were 18 months had such problems versus 33 percent of those adopted between 24 and 42 months.
What brain mechanisms might underlie the lingering deficits? Researchers don't know yet, says Rutter, but the data fit theories of brain programming:
* Experience-expectant programming, which postulates that normal development requires particular developmental experiences.
* Experience-adaptive programming, which proposes that development involves biological adaptation to the environment. For example, the lingering cognitive deficits could be explained by experience-expectant programming, the researchers posit. The Romanian adoptees' cognitive development may have been hampered because their institutional environment lacked social and physical nurturing--evidenced by their malnutrition and smaller head circumferences.
In addition, they speculate that experience-adaptive programming might be at play in the attachment difficulties: Perhaps the children's brains adapted to the deprived institutional environment so that, when they were placed with a family, their brains were not set up to form attachment with their parents.
More research is needed, says Rutter, to explore the theories. However, if it proves true, officials might consider a gradual transition for deprived children entering normal families, says Rutter, since their brains may be "organized in a way that doesn't make it easy for them to deal with all of the things a normal family environment has."
--D. SMITH BAILEY
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