Studies involving groups administered the Wechsler Adult Intelligence Scale (WAIS) and the WAIS-Revised were examined to determine the validity of J. R. Flynn's (1987) findings of massive intelligence quotient gains in a single generation in many nations. Results for sampled adults support Flynn for the average intelligence range only. (TJH)

The sustained attention of 16 mildly retarded and 16 nonretarded adults was assessed during 2 60-minute vigilance tests differing in memory demand. Performance of retarded subjects declined more rapidly in later stages than did that of the nonretarded subjects. Implications for the study of memory load are discussed. (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)

This study evaluated the diagnostic validity of a task measuring abstract categorization ability in learning disabled (LD) and non-LD children. Data showed that the component of abstract category knowledge that best disciminates LD children from non-LD, is the knowledge of how members of abstract categories differ from each other. (Author/JAZ)

Sources of continuity among nine measures of infant cognitive processing and later childhood intelligence quotient were examined through developmental structural equation models applied to a sample of 208 twin pairs measured from 7 to 36 months. Skills assessed appear related to general cognitive ability in a relatively unstable manner. (SLD)

Intelligence quotient (IQ) test performance is reported for 93 families restudied 10 years after the Minnesota Transracial Adoption Study in 1975. Results for 426 subjects support the original finding: being reared in the IQ test culture and prevailing school culture benefits all children's IQ scores and academic achievement. (SLD)

Data from the Colorado Adoption Project for 493 first-grade adopted and nonadopted children are used to separate parental intelligence quotient (IQ) from the effects of school environment. Several of the variables show direct environmental associations with reading and mathematics achievement independent of effects of parental IQ. (SLD)