Also called sociocultural or cultural-familial retardation, mild mental retardation attributed to environmental causes and generally involving some degree of psychosocial disadvantage.
The majority of persons suffering from mental retardation fall into the category of familial retardation rather than that of clinical retardation, which usually has neurological or other organic causes. Persons with familial retardation typically have IQs ranging from 55-69 and show no signs of physical disability. Environmental causes thought to contribute to familial retardation include the quality of the mother's prenatal care, maternal and child nutrition, family size, the spacing of births within a family, disease, and health risks from environmental toxins such as lead. The 1994 publication of The Bell Curve, an analysis, by Richard J. Herrnstein and Charles Murray, of the relative importance of heredity and environment in determining IQ scores, and the 1995 release of the most in-depth study to date on retardation among school children both renewed public interest in familial retardation and its causes.
Familial retardation is usually not detected until a child enters school and has academic difficulties, at which point the teacher recommends psychological evaluation. Unlike the parents of clinically retarded children, who generally seek out help for their youngsters, the parents of those with familial retardation may take offense when their children are labeled mentally retarded and deny that there is a problem, especially since their children are often able to function competently in their daily lives outside school. Some studies have shown that educators are more likely to classify poor and/or minority children as mentally retarded, while labeling white middle-class children with comparable IQ scores as learning disabled. Other critics have pointed out that familial retardation may be diagnosed in children who are simply unprepared to cope with the demands of school because of cultural and linguistic isolation.
Familial retardation may be reduced by nutritional, health, and educational intervention at an early age. In a study conducted in the 1970s, educators selected mother-child pairs from among a group of women with IQs under 75 living in the poorest section of Milwaukee, Wisconsin, while establishing a control group of mothers in the same neighborhood with IQs over 100. For the first five years of the children's lives, the targeted group of mothers and their children received instruction in problem-solving and language skills, as well as counseling to motivate them to learn and succeed. The mothers and children in the control group received no form of environmental enrichment. At the age of five, the children in the target group had IQ scores averaging 26 points higher than those of the children in the control group. At the age of nine, their average IQ was 106 (slightly above the universal norm of 100), while that of the other children was only 79. (Later results, however, were somewhat disappointing, as the mothers' motivation to continue the program became difficult to maintain over the long term.)
In 1995, an Atlanta study conducted jointly by the Centers for Disease Control and Prevention and Emory University found important new evidence linking mild retardation to social and educational deprivation. It was found that 8.4 out of every 1,000 10-year-olds were mildly retarded (defined as an IQ of 50-70), while 3.6 of every 1,000 suffered severe retardation due to such conditions as cerebral palsy or Down syndrome. The incidence of mild retardation was 2.6 higher in blacks than whites, although this difference was halved when socioeconomic factors were taken into account. Children of all races were four times as likely to be mildly retarded if their mothers had not finished high school. The incidence of mental retardation was also slightly higher for children of teenage mothers. The Atlanta study also confirmed earlier claims that teachers are more likely to seek IQ testing for minority children from poor families. Based on the findings of this survey, the federal government launched a pilot program to improve health and education for disadvantaged mothers and children, with special emphasis on providing a more intellectually stimulating home environment for at-risk youngsters through reading programs and other activities.
As adults, socioculturally retarded individuals live in a variety of settings, including their parental homes, group homes, and their own independent residences. Very few are institutionalized. Most make a satisfactory adjustment to adult life in their communities, although their adjustment in early adulthood is likely to be more difficult than that of the average person. Often they must learn from their own life experiences lessons that others learned (or at least were introduced to) at home. Eventually, however, most become responsible and self-supporting members of their communities with the ability to meet adult responsibilities and commitments.
Fraser, Steven. The Bell Curve Wars: Race, Intelligence, and the Future of America. New York: Basic Books, 1995.
Herrnstein, Richard J., and Charles Murray. The Bell Curve: Intelligence and Class Structure in American Life. New York: Free Press, 1994.