Latent dimensions underlying individual differences in performance of information-processing tasks and dual task combinations, and the existence of a time-sharing (TS) ability were studied in 81 male college students. Supportive evidence for a general TS ability was not found. An identified TS factor specific to task combinations is discussed.…

The relationship between general intelligence and the ability to ignore irrelevant stimuli appearing in the same visual field as an attended target was studied for 167 college students. Results indicate that psychometric intelligence does not tap visual focused attention. (SLD)

This study investigated whether a unitary elemental process or several independent processes underlie psychometric "g" (factor of general intelligence). Results with 101 college students administered 2 intelligence tests and a large battery of elementary cognitive tasks suggest that as many as 4 independent components make up…

Used steady-state probe topography to investigate the cortical activity of 12 average and 12 high IQ Australian college students during a spatial working memory task. Results, in terms of changes in visual evoked potentials, suggest that the areas of the brain involved in working memory are influenced by individual differences in intelligence.…

Taking into account various models and findings pertaining to the nature of analogical reasoning, this study explored quantitative and qualitative individual differences in intelligence using latency and eye-movement data. Fifty-five university students were administered 14 selected items of the Raven's Advanced Progressive Matrices test. Results…

The latency and amplitude of the P300, an event-related potential, during the performance of a memory-scanning task were used as indices of the efficiency of information processing that may mediate individual differences in intelligence. Results with 61 female college students contradict a pure speed of processing explanation of the relationship…

Because they used an inappropriate statistical procedure, J. H. Kranzler and A. R. Jensen (1991) have not demonstrated that a factor of general intelligence ("g") depends on several independent factors. A factorial reanalysis of their data suggests that speed and efficiency of information processing are important in "g." (SLD)

The hypothetical idea of a perfectly pure psychometric "g" is empirically unattainable. Because the unity of "g" cannot be proved or disproved by factor analysis, the unitary "g" hypothesis represents a parsimonious assumption. J. B. Carroll's (1991) analysis demonstrates the relationship between psychometric and…

In their reply to the present author's critique (1991), J. H. Kranzler and A. R. Jensen have still not demonstrated that a factor of general intelligence, "g," depends on, or contains, several independent factors. They have only demonstrated that an estimate of "g" is predictable from several independent components. (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)

Individual differences in performance on 4 computer-controlled visual memory and recognition tasks as a function of performance on 5 paper-and-pencil spatial tests were studied for 90 psychology students attending the University of Rennes (France). Results show that spatial thinking is partially supported by visual memory. (SLD)

Two studies involving 274 Air Force recruits and 163 college students, respectively, investigated the relationship between priming effects and declarative knowledge acquisition within repetitive practice models. Individual differences in repetition-priming effects uniquely predicted learning differences relative to other cognitive 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)

Individual differences in confidence judgments made by subjects on the accuracy of their answers to psychological test items were studied with 271 Australian college students. Findings suggest that confidence ratings, like the accuracy scores from the tests of human abilities, are stable and reliable measures of between-subjects variability. (SLD)