Data are presented from families of monozygotic twin pairs which give evidence of genetic variance on the Block Design Test, a nonverbal measure of intelligence. Analyses of genetic and environmental effects on behavior are possible with this kind of information. (SA)

Cognitive, academic, and behavioral characteristics of 42 children with learning disabilities were assessed from identification at age 6-7 to the age of 11.5. At endpoint, resource students showed a drop in verbal intelligence quotient and lower achievement compared to mainstreamed students, though there were no differences at the time of…

Sex difference research has been plagued with a myriad of problems,. Specifically, intelligence testing, if dependent on measurement of spatial or verbal proficiency, may not be an accurate indicator of native ability. Similarly, infrequent replication of studies, studies that only include subjects of one sex yet imply sex differences, and poor…

A projective role taking task (RTT) was revised with respect to procedure and scoring categories for use with the mentally retarded. The revised RTT was administered to 123 educables. Results indicated significant associations between mental age and various indices of the retardates' role taking behavior. These associations remained significant…

Noting that many of the attacks on individual scientists as well as some of the attacks on the field of behavior genetics are more than intemperate--they are non-rational--the author discusses his experience as a signatory to a document drawn up by Ellis B. Page during the winter of 1971-1972. The intent of this controversial document was to…

Sixteen individuals with autism and sixteen with Down's Syndrome, aged 10-29, were matched for verbal mental age. The groups' scores did not differ on the Vineland Adaptive Behavior Scales. However, the adaptive skills of Down's Syndrome individuals kept pace with mental age, while the skills of autistic subjects did not change. (Author/JDD)

Areas of agreement and disagreement concerning intellectual developmental and the problems of mental retardation espoused by the author and by Uzgiris are discussed in this paper. The importance of environmental factors, along with the genetic and/or constitutional nature of the organism on which these environmental events impinge, is seen as…

This issue of the IRCD Bulletin is devoted to commentaries on an article by Arthur R. Jensen on the nature-nurture controversy in a recent number of "Harvard Educational Review." Contents of the Bulletin are comprised of the following: "Education, Ethnicity, Genetics and Intelligence; Jensenism: Another Excuse for Failure to…

Much of our thinking about contemporary social problems reflects tacit presuppositions regarding the operation of heredity and environment in human behavior. These beliefs have important implications for practical decisions. Advances in genetics, psychology, anthropology, and other disciplines have contributed much to a clarification of the…