Clocking g: Relating intelligence and measures of timed performance

The relationships between intelligence test scores and measures derived from reaction time (RT) and perceptual speed procedures were investigated in 137 twelve-year-old students with IQs ranging from 59 to 142. A range of intelligence tests were used and the scores factor analyzed to produce general, spatial and verbal factors. Test and factor scores were correlated with perceptual speed and with measures taken from 2, 4, and 8 choice RT tasks using a response keyboard upon which the subject's fingers directly rested, thus avoiding interpretive problems associated with a “home key.” Inspection time correlated poorly with intelligence. Only three of the RT measures produced correlations greater than .25 with the general factor. These were the slope of Hick's law, B, (correlation −.28), the 8 choice mean RT, RT8, (−.33) and the 8 choice standard deviation, SD8 (−.41), compared with the average intercorrelation between the intelligence measures of .40. Test-retest correlations of the RT measures, taken over a year for half the subjects, were low as reliability measures, with .35 for B, .52 for RT8, and .48 for SD8. Correlations of RT measures with spatial scores were not significantly greater than with verbal scores, suggesting that whatever relationship exists is with a general factor rather than only a spatial one.     

Ethnicity,school attitudes,intelligence and academic achievement

Regression surface analysis was used to examine relations between school-related attitudes and measures of academic achievement at different levels of intellectual ability, for children from different Australian ethnic groups. The sample included 660 eleven-year-old children from lower social status families, with 250 Anglo Australian children, 170 Greek, 120 Southern Italian, and 120 English children. Regression surfaces were constructed from models that examined possible linear, interaction, and curvilinear relations between the variables. The findings suggest the propositions that: (a) at each level of intelligence, increases in the affective component of school attitudes are not associated with changes in academic achievement, (b) at each level of the affective component of school attitudes, increments in intelligence test scores are related to increases in academic achievement scores, and (c) the relations between academic achievement, intelligence, and the cognitive-behavioral component of school attitudes vary for children from different ethnic groups. The results suggest that the manipulation of the cognitive-behavioral aspects of school attitudes may influence the academic performance of low social status children from different ethnic groups but educational programs that focus on the affective components of school attitudes may not be effective in changing children's academic achievement.     

Cognitive and behavioral attention in children with math difficulties

Cognitive assessments and behavioral ratings of attention were used to examine the relation of inattention to math performance in children. Third grade students with math difficulties (MD; n?=?17) and math and reading difficulties (MDRD; n?=?35) were administered the Attentional Network Test (ANT), as well as achievement and intelligence measures. Strengths and Weaknesses of ADHD-Symptoms and Normal-Behavior-IV (SWAN-IV) Inattention ratings were collected from teachers. Two comparison groups were also recruited: a typically achieving group (n?=?23) and a group that responded to a math-tutoring intervention (responders; n?=?54). On the ANT, children with MD and MDRD did not perform significantly different than typically achieving children or responders on measures of alerting and orienting attention and executive control. All subgroups did demonstrate performance patterns that were expected on the ANT. However, performance across blocks of the task was inconsistent, suggesting poor reliability. There were no relations between ANT performance and SWAN-IV behavioral inattention scores, though behavioral ratings of inattention correlated significantly with math performance. Children with MD and MDRD may have more difficulty with distraction and attention to detail in contextual situations, as opposed to impulsive responding in these settings. The lack of relation between cognitive attention and math performance may suggest that either the ANT does not assess the relevant attention constructs associated with math difficulties or may parallel studies of attention deficit/hyperactivity disorder (ADHD) in which cognitive and behavioral assessments are weakly related.     

动机因素、学习策略、智力水平对学生学业成就的影响

以１１９名高中学生为被试,测量研究了动机因素、学习策略、智力水平对学生学业成就的影响。结果表明,自我效能、内在动机、掌握目标、学习策略、智商分数与学业成就呈显著的正相关,外在动机、业绩目标与学业成就呈显著的负相关。智商分数、学习策略、动机因素与学业成就存在着因果关系,智商分数（β＝０.４７６）、学习策略（β=０．２２０）、自我效能（β＝０.２０７）、掌握目标（β＝０．１８５）对学业成就有显著的回归效应,并直接影响学业成就。而内在动机（β＝０．１８４）通过直接影响学习策略而间接影响学业成就。     

Correlations between intelligence and components of serial timing variability

Psychometric intelligence correlates with reaction time in elementary cognitive tasks, as well as with performance in time discrimination and judgment tasks. It has remained unclear, however, to what extent these correlations are due to top–down mechanisms, such as attention, and bottom–up mechanisms, i.e. basic neural properties that influence both temporal accuracy and cognitive processes. Here, we assessed correlations between intelligence (Raven SPM Plus) and performance in isochronous serial interval production, a simple, automatic timing task where participants first make movements in synchrony with an isochronous sequence of sounds and then continue with self-paced production to produce a sequence of intervals with the same inter-onset interval (IOI). The target IOI varied across trials. A number of different measures of timing variability were considered, all negatively correlated with intelligence. Across all stimulus IOIs, local interval-to-interval variability correlated more strongly with intelligence than drift, i.e. gradual changes in response IOI. The strongest correlations with intelligence were found for IOIs between 400 and 900 ms, rather than above 1 s, which is typically considered a lower limit for cognitive timing. Furthermore, poor trials, i.e. trials arguably most affected by lapses in attention, did not predict intelligence better than the most accurate trials. We discuss these results in relation to the human timing literature, and argue that they support a bottom–up model of the relation between temporal variability of neural activity and intelligence.     

Effects of age and the relationship between response time measures and psychometric intelligence in younger adults

The major goal of the present study was to investigate the potential influence of age on the relationship among performance measures derived from a Hick reaction time task and general intelligence (psychometric g). Participants were 130 male and 130 female younger adults (mean age: 24.6 years) covering a wide range of individual levels of intelligence. Results from structural-equation modelling analyses clearly indicate that there is no evidence for the notion of a general speed factor underlying psychometric g. A much more sufficient model is provided by the assumption that median reaction time (RTmd) and intraindividual variability of reaction time (RTSD), though highly correlated, reflect two distinct sources of variance for psychometric g. While age was negatively associated with RTmd, no such relationship could be established for RTSD.     

Individual and age-related differences in children’s working memory

The purpose of this study was to investigate the degree to which age-related and individual differences in children’s working memory (WM) are due to a general or task-specific capacity system. Experiment 1 correlated children’s (N=146; age range 5–19 years) verbal and visual-spatial working memory performance with various intelligence and achievement measures. The results supporting a general system were that (1) visual-spatial and verbal WM measures were significantly intercorrelated with and without age partialed out and (2) both verbal and visual-spatial WM measures were significantly correlated with diverse achievement and intelligence measures. Experiment 2 compared three age groups (N=192; 7-, 10-, and 13-year-olds) on working-memory performance tasks under initial, enhanced (cued), and maintenance conditions. The results supporting a general capacity system were that (1) age-related performance differences in WM were found on all conditions and not isolated to specific processes, (2) the maintenance measures (high-load condition) predicted the variance better in age-related performance than process measures, and (3) although individual differences in WM performance reflected two independent operations, these operations produced similar correlations to achievement within age groups. Overall, the results support a general capacity explanation of age-related and individual differences in children’s WM performance.     

Relating children's attentional capabilities to intelligence, memory, and academic achievement: a test of construct specificity in children with asthma.

The relationship between attention, intelligence, memory, achievement, and behavior in a large population (N = 939) of children without neuropsychologic problems was investigated in children with mild and moderate asthma. It was hypothesized that different levels of children's attentional capabilities would be associated with different levels of intellectual, memory, and academic abilities. Children ages 6-12 at the eight clinical centers of the Childhood Asthma Management Program (CAMP) were enrolled in this study. Standardized measures of child neuropsychological and behavioral performance were administered to all participants, with analyses examining both the developmental trajectory of child attentional capabilities and the associations between Continuous Performance Test (CPT) scores and intellectual functioning, and measures of memory, academic achievement, and behavioral functioning. Findings demonstrated that correct responses on the CPT increase significantly with age, while commission errors decrease significantly with age. Performance levels on the CPT were associated with differences in child intellectual function, memory, and academic achievement. Overall these findings reveal how impairments in child attention skills were associated with normal levels of performance on measures of children's intelligence, memory, academic achievement, and behavioral functioning, suggesting that CPT performance is a salient marker of brain function.     

The relationship between speed of information processing and cognitive ability

Speed of information processing as measured by various reaction time and inspection tasks has been shown to correlate with psychometric intelligence, and it has been suggested that general intelligence (g) is determined to some degree by the speed that information is processed. If this is so, then various measures of speed of information processing should correlate substantially with each other, and each should also correlate with a wide range of psychometric tests that load on g. Alternatively, intelligence may be considered to be a multi-faceted complex of partially related abilities with specific abilities being dependent upon specific cognitive processes. If this is the case, it should be possible to discover independent cognitive processes, some of which correlate with one facet or broad ability and some with another. This paper presents three experiments in which the relationship between intellectual ability and four speed of information processing measures was examined. These were rate of memory scanning, rate of retrieval of information from long term memory, speed of stimulus-response mapping and inspection time (IT). Results showed that correlations between IT and most reaction time measures of speed of information processing were low, and that correlations between different versions of IT were negligible. In addition, some cognitive tasks with verbal material (memory scanning rate for digits and Posner letter matching IT) correlated most substantially with Verbal Reasoning whereas non-verbal (two-line) IT consistently correlated with tests loading on g. It was thus suggested that while non-verbal IT may be a measure of a perceptual speed attribute that contributes to mental functioning, other “speed of information processing” parameters may be more specific to a subset of abilities.     

Inspection time and its relation to intelligence

Inspection time, defined as the minimum duration for which two different stimuli must be presented if they are to be perceived as different, was measured for both auditory and visual stimuli. The minimum durations were determined by means of a two- alternative forced-choice task for 50 children whose average age was 12 years 2 months. The times were correlated with the children's verbal (Mill-Hill vocabulary) and nonverbal (Raven matrices) intelligence. The Kendall correlation coefficients were ?.3188 and ?.0929 for the auditory and visual inspection times with verbal intelligence, and ?.2322 and ?.2676 for those times with nonverbal intelligence. Auditory and visual inspection times were correlated .1721 with each other. These results do not support earlier claims that inspection time is closely related to conventional measures of intelligence.     

Intelligence, reaction times, and peripheral nerve conduction velocity

Two studies (with sample sizes of 85 and 88) are reported that investigated relationships among measures of intelligence, speed of information processing, and peripheral nerve conduction velocity (NCV). In both studies, NCV was significantly correlated with IQ scores (rs = .42 and .48) and with reaction times (RTs; rs = −.28 and −.18): Thus, faster NCV was associated with higher IQ scores and faster speed of processing. In both studies, NCV and RTs contributed significantly, in combination, to the prediction of fullscale IQ (shrunken multiple Rs = .53 and .57), but the expected pattern of causal relationships between the variables was not borne out. The results are interpreted in terms of a “neural efficiency” model of intelligence, which has recieved support from other studies of physiological correlates of human intelligence.     

Physical attractiveness and academic performance: Beauty is not always talent1

Stepwise multiple regressions were used to determine the relative importance of physical attractiveness in the prediction of academic achievement for two samples of college students. In the first study, only ACT scores made an independent contribution to the prediction of males' (N= 55) grade average. For females (N= 65), verbal IQ (as measured by Borgatta and Corsini's Quick Word Test) and father's education yielded the only independent effects. In the second, follow-up study, males' (N= 50) achievement was significantly positively associated with intelligence and high school grades and negatively associated with attractiveness. For females (N= 87), independent effects were obtained for intelligence, high school grades, socio-economic status (positively correlated), and need for approval (negatively correlated). Attractiveness was again not associated with females' academic performance. In a final study involving high school students, attractiveness was not associated with achievement for 84 boys but was negatively associated for 83 girls. The results are discussed in terms of potential underlying mechanisms and the limitations of a “what is beautiful is good” stereotype.     

The relationship between intelligence,working memory,academic self-esteem,and academic achievement

Academic achievement is crucial for life and long-term outcomes. The aim of the present study is to examine the joint role of cognitive (intelligence and working memory) and non-cognitive (academic self-esteem) factors in predicting academic achievement (mathematics and reading literacy) in a sample of Italian sixth and eighth graders. The results showed that within the cognitive factors considered, intelligence was the best predictor of achievement. As regards to non-cognitive factors, academic self-esteem was effective at predicting achievement after controlling for cognitive measures. Academic self-esteem was also found to have an indirect effect, mediated by intelligence, on academic achievement. Both theoretical and practical implications of the present results are discussed.     

The relationship between memory for order and other cognitive tasks

Measures of memory for order were correlated with measures requiring mental manipulation, achievement, and aptitude using college and fifth grade students. Memory for order was not significantly related to measures of mental manipulation nor achievement measures for college students. For fifth graders memory for order was significantly related to mental manipulation, intelligence, and achievement measures. It is suggested that the nature and capacity of short-term memory changes with age.     

Parents' education and children's achievement: The role of personality

The reasons for the positive association between families' background variables, such as parents' education, and children's academic achievement have not fully been clarified yet. The present study investigates children's intelligence and personality as potential mediators. A sample of 580 German high school students (mean age: M = 17.0; SD = 0.7) indicated the highest education of their parents and completed measures assessing their own personality and intelligence. Children's academic achievement was operationalized by grade point average. Children's intelligence, openness to experience and, marginally, conscientiousness partially mediated the association between parents' education and children's academic achievement. Even after controlling for children's intelligence, the mediating effects of those personality traits held. Results are discussed with regard to potential underlying processes. Copyright © 2010 John Wiley & Sons, Ltd.     

Intelligence and reaction times in the Hick, Sternberg and Posner paradigms

The relationship between psychometric intelligence and reaction times (RTs) in three well-known elementary cognitive tasks (Hick simple and choice reaction time task, Sternberg's short-term memory scanning, Posner's letter matching) was studied in a sample of 116 participants. In conformity with other studies mean RTs and intraindividual variabilities (SDs) of RT were correlated significantly with Raven's Advanced Progressive Matrices (APM). On the basis of the mental speed theory the processing measures or component scores (like slopes in the Hick and Sternberg paradigm and the NI-PI measure in the Posner task) should give the most substantial relationships with intelligence. However, as in other previous studies these measures displayed rather low, albeit significant, relationships with intelligence, which was probably due to the low reliability of these parameters. For the Posner paradigm, we proposed alternative approaches to compute an indicator for long-term memory (LTM) access that gave substantial correlations with intelligence. We conclude that LTM access is significantly associated with psychometric intelligence, whereas up to now there has been no unequivocal evidence for a substantial relationship between short-term memory access in the Sternberg task and intelligence.     

Explaining Social Disparities in Mathematical Achievement: The Role of Motivation

This study examined the role of motivation as a mediator of the relationship between parents' socio‐economic status (SES) and children's standardized test achievement in math. We employed a one‐year longitudinal approach using Programme for International Student Assessment (PISA) 2003 and a follow‐up exam in 2004. The sample consisted of N = 6020 German students (mean age 15.5 years, SD = .55) who continued school after Grade 9 (PISA 2003) and were in Grade 10 at the time of PISA 2004. Children completed measures related to their parents' SES, math‐specific self‐concept, task‐specific and global self‐efficacy, and interest, intelligence and mathematical competence. We found a small to moderate correlation between parents' SES and children's achievement. All motivational constructs partially mediated the relationship between father's SES as well as a family index for SES (economic, social, and cultural status) and children's mathematical competence, but only math‐specific self‐concept and self‐efficacy were significant mediators for mother's SES. Even when simultaneously considering the mediating effect of children's intelligence and prior achievement, the mediation effects of motivation remained significant. These results are important for our understanding of educational equality. Copyright © 2016 European Association of Personality Psychology     

Reaction times and speed-of-processing: Their relationship to timed and untimed measures of intelligence

Eighty-one university students were given a battery of reaction time tests, measuring the speed with which they performed various elementary cognitive processes, and a group test of intelligence which yielded timed and untimed scores. Multiple regression analyses indicated that speed of information-processing was an equally good predictor of timed and untimed intelligence test performance, and that various combinations of speed-of-processing variables accounted for as much as 48% of the variance in intelligence test scores. Different speed-of-processing variables varied relatively systematically in the extent to which they correlated with the individual subtests and scales of the intelligence test.     

Convergence between attention variables and factors of psychometric intelligence in older adults

The purpose of the present study was to examine the hypothesis that individual differences on measures of attention would converge with select factors of psychometric intelligence, especially fluid intelligence and short-term acquisition and retrieval. A sample of 83 elderly adults $\text{(}\text{X}\text{= 71}\text{years}\text{)}$ was administered a battery of 17 psychometric ability tests. Tests were selected to mark four psychometric ability factors (Cattell and Horn's dimensions of fluid and crystallized intelligence, short-term acquisition and retrieval, and perceptual speed). Also, seven tasks representing four aspects of attention—decoding processes, selective attention, attention switching, and concentration—were administered. A confirmatory factor analysis was conducted to examine the relationships among the four psychometric ability factors and 11 variables obtained from the attention tasks. Results were only partially consistent with the hypothesized pattern of convergence. Two attention measures had significant loadings on a fluid-type intelligence factor, and one had a marginally significant loading on a short-term memory factor. In general, the greatest convergence occured between attention variables and the ability factor of Perceptual Speed. Results were discussed with respect to previous research on psychometric abilities and cognitive processes, the theory of fluid-crystallized intelligence, and their implications for understanding intellectual aging.     

Ability factors and cognitive processes

Several measures of the speed of information processing were related to ability factors derived from the Cattell-Horn theory of fluid and crystallized intelligence. Ninety-one college students took a battery of paper and pencil tests designed to measure four ability factors: fluid intelligence (Gf), crystallized intelligence (Gc), spatial visualization (Gv), and clerical perceptual speed (CPS). They also performed paper and pencil and computerized versions of three information processing tasks: mental rotations, letter matching, and sentence verification. Correlations among the ability measures, among the information processing measures, and between the two domains were analyzed using confirmatory factor analysis. The four ability factors were found to be largely independent in this college population. Speed of letter-matching and sentence verification were highly correlated, but neither was related to speed of mental rotation. Mental rotation speed was strongly correlated with Gv; letter matching speed was correlated with CPS; and sentence verification speed was correlated with both Gc and CPS.