Taylor (1980) claims to show that the similarity in IQ between monozygotic twins reared apart found in prior studies is due to similarity in their environments. A reanalysis using Taylor's classification of environments but an alternative IQ measure shows that his findings do not constructively replicate. (Author/RD)

This editorial suggests how the approaches of differential psychology and information processing psychology should be combined to study intelligence. Methods reviewed include factor analysis, componential analysis, and computer simulation. Guidelines for the specification of subtheories of intelligence, as well as future theories and methods for…

A reevaluation of a number of experiments suggests that normal and retarded persons differ on short-term memory tasks from the time of initial stimulus exposure. The hypothesis that memory differences are due to differential encoding as a result of more adequate rehearsal by the normal subjects is unacceptable. (Author/BW)

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)

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…

Individual differences in visual recognition memory and intelligence were correlated using 52 five-year-olds whose IQs ranged from 40-136. The correlation between memory performance and IQ was .70 for whole sample, and .61 when children with IQs below 75 were omitted. Immediate recognition memory is highly associated with intelligence. (Author/RD)

Normal and retarded adolescents recalled consonants after 0, 9, and 27 seconds of tonal detection and performed the detection task without recall. Subjects were classified as rehearsers or nonrehearsers, depending upon variations in tonal detection accuracy or response times across conditions. Normal and retarded nonrehearsers showed equal…

The question of how to integrate developmental (Piagetian) and psychometric conceptions and assessments of intelligence is considered. A solution which incorporates the contributions of each position--intelligence as forms and as traits--is offered. Premises and objectives of each tradition are reviewed and compared. Overlaps make synthesis…

Data from the General Social Survey (GSS) collected in the years 1990-1996 are examined for the relationship between fertility and intelligence as measured by vocabulary. The results show that the relation between fertility and intelligence has been consistently negative for successive birth cohorts from to 1900 to 1979, indicating the presence of…

The hypothesis that racial differences in IQ stem from differences in components of executive systems including knowledge base, control processes, and metacognition was investigated. Group differences in metamemory, strategy use, and general knowledge, but not perceptual efficiency, were observed. Metamemory predicted crystallized but not fluid…

Persons representing the extremes of intelligence cannot be included in the same study unless they are approximately equated on mental age, in which case the relative performances of the extreme groups can provide useful information about the nature of intelligence. (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)

This paper investigates the differentiation of cognitive abilities as a function of neuroticism. Specifically, we examine Eysenck and White's [Eysenck, H. J., and White, P. O. (1964). Personality and the measurement of intelligence. British Journal of Educational Psychology, 24, 197-201.] hypothesis that cognitive abilities are less differentiated…

Lynn [Lynn, R., 2002. Sex differences on the progressive matrices among 15-16 year olds: some data from South Africa. "Personality and Individual Differences 33," 669-673.] proposed that biologically based developmental sex differences produce different IQ trajectories across childhood and adolescence. To test this theory we analyzed the…

The impetus for our study was the contention of both Lynn [Lynn, R. (1991) "Race differences in intelligence: A global perspective." "Mankind Quarterly," 31, 255-296] and Rushton [Rushton, J. P. (1995). "Race, evolution and behavior: A life history perspective." New Brunswick, NJ: "Transaction"; Rushton, J.…