Proposes a developmental theory of sex differences in intelligence that states that the faster maturation and brain size growth in girls up to age 15 compensates for their smaller brain size so that sex differences in intelligence are very small. Discusses evidence that supports this theory. (SLD)

Cranial capacities were calculated from external head measurements reported for a stratified random sample of 6,325 Army personnel measured in 1988. Data suggest that human populations differ in brain size by race and sex. The major source of variation in data was sex; race was second and rank last. (Author/SLD)

In studies of the relationship between masculinity-femininity and intelligence, data should be analyzed using correlational analysis for the complete distribution, rather than analysis of variance of extreme groups. The earlier work of Baucom and Welsh (EJ 171 822) was used as illustration. (BW)

Humphreys' criticisms (TM 503 269) of the work of Welsh and Baucom (EJ 171 822) are inappropriate since his findings are based upon a different measure of masculinity-femininity and a population which is somewhat different. Also, his insistence on correlational analysis to the exclusion of extreme group design is viewed as inappropriately…

Raw scores on WISC-R subtests and the verbal, performance, and full scale IQ scales were correlated with age separately for White and Black males and females. The relationship between age and intelligence test performance was constant across race and sex and supports the construct validity of the WISC-R. (Author/RD)

Two studies examined differences in intellectual ability associated with masculinity and femininity in high school and college students. Available from: Ablex Publishing Corporation, 355 Chestnut Street, Norwood, New Jersey 07648. (CL)

Cranial capacities are calculated from external head measurements reported for 40 samples (tens of thousands of subjects) from a 1990 review of ergonomically important body measurements compiled by the International Labour Office. The correlation between brain size and intelligence for groups and individuals is discussed. (SLD)

To study whether individual differences in general cognitive ability differ in males and females, full-scale IQ data from 426 child twin pairs were fitted to a structural equation model of sex limitation. Individual differences in general cognitive ability appear to be substantially due to common genetic influences in males and females. (SLD)

Students of high intellectual ability and their parents were tested on a battery of cognitive tests. Vernon's model of intelligence best fit results. A verbal-educational and a practical-spatial-mechanical factor explained most performance variance. Among children, age related to verbal but not spatial or mechanical abilities. (Author/RD)

Three experiments were conducted with 91 male and 91 female university students to assess sex differences in performance on speeded matching tests and theory on same-different judgments. Results are interpreted via the dual-process hypothesis of same-difference judgments with sex differences explained in terms of serial comparison processes rather…

This study examines cultural bias in the Wechsler Intelligence Scale for Children. Results indicated no evidence of specific factors peculiar to Blacks v Whites, and rank order of item difficulties was similar in both groups. Race differences were due to differences in mental maturity rather than to test bias. (Author/RD)

Three studies of college students found a sex difference in the correlation of memory scanning rate, short- and long-term components of free recall, and word recognition with memory span. Findings are discussed in terms of prior work and a theory presented to account for the obtained sex differences. (Author/RD)

An analysis of intelligence quotient (IQ) in relation to head size was performed on about 14,000 children aged 4 and 7 years, almost equally divided by race (white and black) and sex. Correlation between head size (by inference, brain size), and IQ is established as a within-families correlation. (SLD)

Studied sex differences in general intelligence in 10,475 adults taking cognitive test batteries. Results suggest a negligible difference in general intelligence, a finding consistent with findings from quite different test batteries and subject samples. (SLD)

Magnetic resonance imaging was used to demonstrate that larger brain size (corrected for body size) was associated with higher intelligence quotient (IQ) for 40 right-handed college students grouped by high and average IQ and sex. Results suggest the relevance of brain size to intelligence test performance. (SLD)