A Canadian study compared the rate of cognitive disabilities in 156 relatives of 49 individuals with autism to that found in 55 relatives of 18 individuals with mental retardation. No differences were found; however, female and low IQ individuals were found to have higher family histories of cognitive disabilities. (Author/CR)

Genetic effects on specific cognitive abilities as distinct from those on general cognitive ability were studied in 302 pairs of twins (some reared together, some apart) from the Swedish Adoption/Twin Study of Aging. Overall, results showed significant genetic influence on specific abilities independent of influence on general ability. (SLD)

Chinese and Japanese immigrants to the United States and Canada have survived years of discrimination and oppression and today demonstrate academic and professional achievements that are often better than those of whites. However, the Asians continue to obtain higher scores on nonverbal/spatial tests than on verbal tests and tend to be…

Swedish longitudinal studies of twins support Scarr-Salapatek's explanation of nature-nurture influences on intelligence. This model predicts more genetic variance in test results for advantaged than disadvantaged groups. Jensen's work, however, suggests equal amounts of variance among different social classes. (Author/CP)