Examined the assumption that Spearman's law acts unsystematically and approximately uniformly for various subtests of cognitive ability in an IQ test battery when high- and low-ability IQ groups are selected. Data from national standardization samples for Wechsler adult and child IQ tests affirm regularities in Spearman's "Law of Diminishing…

A correlation between intelligence level (IQ) and nerve conduction velocity (NCV) was demonstrated for 147 undergraduate students in the eastern San Francisco (California) Bay area. Recent studies of retarded subjects support the findings, explainable by positive correlations among NCV, speed of information processing, and IQ. (Author/SLD)

The performance on a battery of cognitive tests of an individual with extraordinary ability at mental arithmetic was studied. Implications of the rather ordinary test performance of Shakuntala Devi in contrast with her calculating speed are discussed with reference to memory and information processing. (SLD)

Correlations among peripheral nerve conduction velocity (NCV), brain NCV, simple and choice reaction times, and a standard measure of intelligence were investigated for 200 male college students. No correlation was found between any arm NCV and the intelligence score. Neurophysiological bases of human information processing and intelligence are…

Data are presented on body weight and cranial capacity for 211 young adult male Caucasians (postsecondary students). The data do not support Rushton's claim for a greater weight-adjusted cranial capacity of Mongoloid males. Speed and efficiency of cortical information processing may be more important for intelligence than brain size. (SLD)

This study examines the nature of the highly variable black-white difference across diverse tests and indicates the major systematic source of this between-population variation, namely, Spearman's g. Eleven large-scale studies (discussed in the appendix), each one comprising anywhere from 6 to 13 diverse tests, show a significant and substantial…

Information processing was measured in terms of reaction time and movement time to stimulus displays which differed in amount of information transmitted. Only reaction time increased as a linear function of number of bits in the stimulus display. Both show individual differences which significantly correlated with intelligence. (Author/RD)

Choice reaction time and simple reaction time were measured for 147 young adults for whom significant positive correlation between nerve conduction velocity in a brain nerve pathway and nonverbal intelligence was previously found. Results suggest that two largely independent neurophysiological processes affect intelligence. Differences in choice…

Measurements derived from reaction time, movement time, and an index of neural adaptability derived from averaged evoked potentials are significantly related to each other as well as to g factor scores extracted from a battery of 15 psychometric tests in a sample of 54 severely retarded adults. (Author/RD)

The Kaufman Assessment Battery for Children (K-ABC) and the Wechsler Intelligence for Children-Revised (WISC-R) were compared with respect to the magnitudes of the average White-Black differences in standardized scaled scores and in raw scores. Subjects were 172 fourth- and fifth-grade children matched in Black-White pairs. (Author/LMO)

This study is based on three distinct elementary cognitive tasks using chronometric techniques: (1) the S. Sternberg memory scan task, (2) a visual scan task; and (3) the Hick paradigm. Certain parameters of the tasks are compared experimentally and correlationally. Subjects were 48 university students, tested and retested on the tasks in a…

Borkowski and Krause (1983) concluded that the locus of black-white intelligence differences lies in metaprocesses not elementary cognitive processes. However, some variables were difference scores with unacceptably low reliability. Magnitude comparisons of racial differences give a different picture of results; comparable differences in measures…

The effects of controlling for individual differences in simple reaction time (RT) on the correlations of choice RT and discrimination RT with intelligence quotient were studied for 213 male college students. Simple RT was controlled by subtraction, partial correlation, and multiple correlation. (SLD)

Two studies with 658 white and 353 African-American elementary school children performing reaction time tasks are offered in support of Spearman's hypothesis about the relative size of the mean African-American-white differences on mental tests as a function of the tests' loadings on psychometric "g." (SLD)

In a study of the relationship between speed of information processing and general intelligence, vocational college students (50 black males and 56 white males) took eight different reaction time tests measuring the speed with which individuals perform various elementary cognitive processes, and a group test of scholastic aptitude (the Armed…