The authors are emmersed in a comprehensive review of the literature on intellectual sex differences. This paper consists of the first progress report and the tentative hypotheses of the work completed so far. Discussion is initially concerned with verbal and spatial abilities. It is concluded that girls learn language earlier, and may continue to…

Army alpha longitudinal data on the same 96 males tested in 1919, 1950, and 1960 were analyzed in addition to data on 123 undergraduates tested in 1972-4. Young adults in 1919 and 1970 were similar. Results suggest that traditional factor analysis taxonomies for young adults misrepresent elderly persons. (Author/CP)

Several key variables in the development and assessment of young children's sex role preference are examined in this study. A sample of 257 pre-kindergarten children (mean age, 59 months) and their mothers participated in this study. After obtaining information on each child's age, IQ, and his/her mother's employment status the It Scale for…

This final report reviews the second phase of a life-span study of boys with fragile X syndrome (FSX), the most common known inherited cause of mental retardation. Males with the syndrome are more severely affected than females and in males, delays are usually evident in all the developmental domains, although cognitive and communication skills…