Cattell's Culture Research Articles

Auditory event-related potentials, neurocognition, and global functioning in drug naïve first-episode schizophrenia and bipolar disorder.

Deficits in event-related potential (ERP) including duration mismatch negativity (MMN) and P3a have been demonstrated widely in chronic schizophrenia (SZ) but inconsistent findings were reported in first-episode patients. Psychotropic medications and diagnosis might contribute to different findings on MMN/P3a ERP in first-episode patients. The present study examined MMN and P3a in first episode drug naïve SZ and bipolar disorder (BPD) patients and explored the relationships among ERPs, neurocognition and global functioning. Twenty SZ, 24 BPD and 49 age and sex-matched healthy controls were enrolled in this study. Data of clinical symptoms [Positive and Negative Symptoms Scale (PANSS), Young Manic Rating Scale (YMRS), Hamilton Depression Rating Scale (HAMD)], neurocognition [Wechsler Adult Intelligence Scale (WAIS), Cattell's Culture Fair Intelligence Test (CCFT), Delay Matching to Sample (DMS), Rapid Visual Information Processing (RVP)], and functioning [Functioning Assessment Short Test (FAST)] were collected. P3a and MMN were elicited using a passive auditory oddball paradigm. Significant MMN and P3a deficits and impaired neurocognition were found in both SZ and BPD patients. In SZ, MMN was significantly correlated with FAST (r = 0.48) and CCFT (r = -0.31). In BPD, MMN was significantly correlated with DMS (r = -0.54). For P3a, RVP and FAST scores were significant predictors in SZ, whereas RVP, WAIS and FAST were significant predictors in BPD. The present study found deficits in MMN, P3a, neurocognition in drug naïve SZ and BPD patients. These deficits appeared to link with levels of higher-order cognition and functioning.

Evaluating the relationship between psychometric intelligence and cognitive functions in paediatric multiple sclerosis.

BackgroundProcessing speed is frequently reduced in patients suffering from multiple sclerosis (MS). Reduced processing speed can also lead to impaired working memory capacity (WMC) in adult MS patients. Less is known about the interplay of cognitive deficits in paediatric MS patients.ObjectivesIn the present study, we investigated whether processing speed and WMC are reduced in paediatric MS patients compared with healthy controls and whether reduced processing speed and WMC might explain potential differences in psychometric intelligence between MS patients and healthy controls.MethodsTwenty-one paediatric MS patients and 21 healthy controls completed a reaction time (RT) task, a working memory task, and Cattell’s Culture Fair Test (CFT20-R).ResultsPatients with MS had slower RT and lower intelligence scores than healthy controls. We could find no significant differences for WMC. An analysis of covariance revealed that group differences in intelligence could be partially explained by processing speed differences.ConclusionThe results indicate that processing speed is a good marker for MS-related impaired efficiency and increased error-proneness of the central nervous system in higher-order cognition as required by Cattell’s CFT20-R.

Speed- and accuracy-related measures of an intelligence test are differentially predicted by the speed and accuracy measures of a cognitive task

Raw scores on time-limited multiple-choice intelligence tests are determined by incorrect responses and missing answers. Both these error types were previously found to be negatively related to each other. Individual differences in the emphasis on speed or accuracy can explain this finding. But even though individual differences in the emphasis on speed or accuracy have been identified not only in intelligence tests but also in cognitive tasks, little is known about their interplay. Therefore the aim of the present study was to investigate to what degree speed- and accuracy-related performance scores of an intelligence test can be predicted by speed and accuracy measures of cognitive tasks, respectively. For this purpose, 200 participants completed Cattell's Culture Fair Intelligence Test (CFT 20-R) and performed the Swaps Task, an experimental cognitive task. To investigate the interplay between the speed and the accuracy measures of both kinds of task, a latent variable approach was used. Overall, the emphasis on speed or accuracy was not systematically related to the intelligence score. However, closer inspection of the data revealed that reaction times, but not errors rates, in the Swaps Task predicted the number of not-reached items as an indicator of speed in the CFT 20-R. At the same time, error rates, but not reaction times, in the Swaps Task predicted incorrect responses as an indicator of accuracy in the CFT 20-R. Taken together, speed- and accuracy-related performance scores of an intelligence test were predicted by speed and accuracy measures of a cognitive task, respectively. Most important, however, the finding that the emphasis on speed or accuracy was not significantly related to intelligence scores clearly indicated that this emphasis does not interfere with the validity of the intelligence test.

Fluid intelligence, emotional intelligence, and the Iowa Gambling Task in children

This study explored the roles of fluid intelligence and emotional intelligence (EI) in predicting performance on the Iowa Gambling Task (IGT) in intellectually average and gifted children. One hundred and twenty-five average children and ninety-eight gifted children were tested with Cattell's Culture Fair Intelligence Test, the Trait Emotional Intelligence Questionnaire-Child Form and the IGT. It was currently found that intellectually gifted children demonstrated better IGT performance than their average peers, including superior decision-making strategies, decision-making speeds and conceptual knowledge stages in the IGT. Fluid intelligence and emotional intelligence played different roles in predicting IGT performance in average and gifted children: average children's IGT performance was related to fluid intelligence and EI, whereas gifted children's IGT performance was associated only with fluid intelligence. IGT performance was more strongly associated with cognitive processes compared to emotional processes. The present study helps to explain how cognitive and emotional processes interact in intellectually average and gifted children's decision making.

Hans J. Eysenck and Raymond B. Cattell on intelligence and personality

The two most prominent individual differences researchers of the twentieth century were Hans J. Eysenck and Raymond B. Cattell. Both were giants of scientific psychology, each publishing scores of books and hundreds of empirical peer-reviewed journal articles. Influenced by Hebb's distinction between physiological (Intelligence A) and experiential (Intelligence B), Eysenck focused on discovering the underlying biological substrata of intelligence. Analogously, Cattell proposed the Gf–Gc theory which distinguishes between fluid and crystallised intelligence. Cattell's Culture Fair Intelligence Test (CFIT), a measure primarily of fluid intelligence, was constructed specifically to minimise differences in test bias in IQ scores between different ethnic/racial groups. Within the personality realm, Eysenck adopted a pragmatic three-factor model as measured via the Eysenck Personality Questionnaire (EPQ-R) and its variants. In contrast, Cattell employed a lexical approach that resulted in a large number of primary and secondary normal and abnormal personality trait dimensions, measured via the Sixteen Personality Factor Questionnaire (16PF), and the corresponding Clinical Analysis Questionnaire (CAQ), respectively. Recent molecular genetics findings provide empirical confirmation of Eysenck and Cattell's positions on the biological underpinnings of personality and ability traits, allowing an improved understanding of the causes of individual differences.

Impact of Antenatal Glucocorticoid Therapy and Risk of Preterm Delivery on Intelligence in Term-Born Children.

Women at risk of preterm delivery are routinely treated with synthetic glucocorticoids (sGCs). Although this therapy substantially reduces neonatal morbidity, concerns remain whether sGC excess may disrupt neurodevelopmental trajectories underlying cognitive functioning. The present study is the first to disentangle direct effects of antenatal sGC treatment on possible long-term cognitive disadvantages from those of pregnancy complications and prematurity. This cross-sectional study included a mixed-sex cohort of 222 term-born children (aged 6-11 years) consisting of three groups: children of mothers admitted to hospital for threatening preterm delivery who had been treated (n = 97) or untreated (n = 36) with sGCs, and controls without pregnancy complications (n = 89). Antenatal sGC treatment consisted of single courses with dexamethasone or betamethasone. Psychometric intelligence was assessed using a German adaption of Cattell's Culture Fair Test. Children born to mothers at risk for preterm delivery scored, on average, 6-7 IQ points below children of mothers without pregnancy complications, irrespective of antenatal sGC treatment. Compared to females, boys were found to be more susceptible to cognitive disadvantages associated with maternal risk for preterm delivery. Our data indicate that conditions related to a threatening preterm delivery rather than antenatal sGC treatment per se are associated with long-term decreases in the child's intelligence. Although these findings imply that a single course of sGC therapy does not aggravate long-term cognitive deficits, they highlight the need for interventions to reduce the detrimental consequences of distress induced by a threatening preterm delivery.

Intelligence does not correlate with inhibitory ability at every age

Accumulating evidence suggests that inhibitory ability is related to intelligence, while other studies don’t confirm this finding. This study explored the relationship of intelligence to inhibitory control in primary school children, aged 7- to 8-year-old, 9- to 10-year-old and 11- to 12-year-old. Raven's advanced progressive matrices and Cattell's Culture Fair Test were administered. The inhibitory ability was measured with a computerized Stroop Test. There was only significant correlation between intelligence and Stroop Test on 11- to 12-year-old children. These results suggested that the relationship between intelligence and inhibitory control was dependent on the participants’ age. © 2009 Published by Elsevier Ltd.

Conflict control of children with different intellectual levels: An ERP study

Conflict control is an important cognitive ability in human behavioral regulation. The Eriksen flanker task was employed to explore the neural correlation between conflict control and intelligence with the aid of event-related potential (ERP) techniques. Two groups of early adolescents with different intellectual levels participated in the current study (an intellectually gifted group of 20 children vs. an intellectually average group of 21 children, with mean scores of 43 vs. 35.7 in Cattell's Culture Fair Test, respectively). Behavioral results indicate that the gifted children had better conflict control performances, with increased accuracy and faster response speeds than the intellectually average children. Electrophysiological results further show that the gifted children had more efficient N2 activations during conflict monitoring processing, faster P3 responses over frontal regions, and stronger P3 activations over central–parietal regions during attentional control processing. The difference waveform analysis showed that the gifted children had the weakest N2d activations when elicited by multiple conflicts. N2d amplitudes can be used to distinguish a stimulus conflict from a response conflict, and P3d amplitudes can be used to separate multiple conflicts from a single conflict. The results support the neural efficiency hypothesis of intelligence and shed light on the close relationship between conflict control ability and human intelligence.

Puberty timing and fluid intelligence: A study of correlations between testosterone and intelligence in 8- to 12-year-old Chinese boys

Sex hormone such as testosterone was recently recognized as an important contributor of spatial cognition and intelligence during development, but the relationship between puberty timing and intelligence especially in children is largely unknown. Here in this study, we investigated the potential relationship between the level of sex hormones in saliva and fluid intelligence in 8- to 12-year-old Chinese boys. Fluid intelligence was measured by the Cattell's Culture Fair Intelligence Test. 1600 children aged 8-12 years were included in the Cattell's Culture Fair Intelligence Test and saliva samples were collected thereafter from 166 boys with normal intelligence distribution, composed of 49, 54 and 63 boys in 8-, 10- and 12-year-old group respectively. The level of salivary testosterone and estradiol was measured with enzyme-immunoassay technique. Data of BMI and age were collected. The relationship between the level of salivary sex hormones and fluid intelligence was analysed by correlation test. There was no significant correlation between salivary testosterone level and fluid intelligence in 8-year-old boys, whereas there was a significant positive correlation in 10-year-old boys and a significant negative correlation in 12-year-old boys between those two variable. To verify the correlation, we performed stepwise multivariate linear regression and discriminant analysis, with both the age and BMI of the boys and their parents, and salivary estradiol level considered. The results showed that the level of testosterone and intelligence was correlated, and the correlation was much stronger when the level of salivary testosterone was higher than 14 pg/ml. In summary, the study suggests that the relationship of testosterone and intelligence varies from late childhood to early adolescence, and the puberty timing is closely related with fluid intelligence.

Neural substrates of the Topology Test to measure fluid reasoning: An fMRI study

In our prior study the negative correlation between Topology, a behavioral measure of fluid reasoning, and adult age diminished with the increase in the level of expertise in a cognitively-demanding domain of expertise in the game of GO. The present fMRI study was designed to investigate neural substrates of Topology. The modified topology sub-test of Cattell's Culture Fair Intelligence Tests was used as cognitive stimuli. The results indicated that higher-order cognition of Topology was supported by neural networks in: (1) the parietal cortex which is involved in activating possible responses based on learned stimulus-response associations, and (2) the prefrontal cortex that is recruited when there is a need to generate and evaluate hypotheses, and select between competing responses. Our results were consistent with previous neuroimaging studies of reasoning using Raven's Progressive Matrices that revealed the engagement of the prefrontal cortex and the parietal cortex in inductive reasoning. The future need was discussed to systematically examine neural networks supporting Topology over the course of expertise development and adult development in order to specify unique aspects of fluid reasoning that support high levels of cognitive behaviors of Topology.

Age and Flexible Thinking: An Experimental Demonstration of the Beneficial Effects of Increased Cognitively Stimulating Activity on Fluid Intelligence in Healthy Older Adults

ABSTRACT The disuse hypothesis of cognitive aging attributes decrements in fluid intelligence in older adults to reduced cognitively stimulating activity. This study experimentally tested the hypothesis that a period of increased mentally stimulating activities thus would enhance older adults' fluid intelligence performance. Participants (N = 44, mean age 67.82) were administered pre- and post-test measures, including the fluid intelligence measure, Cattell's Culture Fair (CCF) test. Experimental participants engaged in diverse, novel, mentally stimulating activities for 10–12 weeks and were compared to a control condition. Results supported the hypothesis; the experimental group showed greater pre- to post-CCF gain than did controls (effect size d = 0.56), with a similar gain on a spatial-perceptual task (WAIS-R Blocks). Even brief periods of increased cognitive stimulation can improve older adults' problem solving and flexible thinking.

Voxel-based morphometry and stereology provide convergent evidence of the importance of medial prefrontal cortex for fluid intelligence in healthy adults

We investigated whether a relationship exists between frontal lobe volume and fluid intelligence as measured by both Cattell's Culture Fair test and the Wechsler Adult Intelligence Scale-Revised (WAIS-R) Performance scale, but not with crystallized intelligence as measured by the WAIS-R Verbal scale, in healthy adults, using two well-established image analysis techniques applied to high-resolution MR brain images. Firstly, using voxel-based morphometry (VBM), we investigated whether a significant relationship exists between gray matter concentration and fluid intelligence on a voxel-by-voxel basis. Secondly, we applied the Cavalieri method of modern design stereology in combination with point counting to investigate possible relationships between macroscopic volumes of relevant brain regions defined as dorsolateral, dorsomedial, orbitolateral, and orbitomedial prefrontal cortex on the basis of neuroanatomical landmarks, and fluid intelligence. We also examined the effect on these relationships of normalizing regional brain volumes to intracranial volume. VBM analysis revealed a positive correlation between gray matter concentration in the medial region of prefrontal cortex and Culture Fair scores (corrected for multiple comparisons), and also WAIS-R Performance Intelligence sum of scaled scores (SSS) (uncorrected for multiple comparisons before controlling for age, and this converges with the stereological finding of the positive correlation between volume of dorsomedial prefrontal cortex normalized to intracranial volume and Culture Fair scores after controlling for age. WAIS-R Verbal Intelligence SSS showed no correlations. We interpret our findings, from independent analyses of both VBM and stereology, as evidence of the importance of medial prefrontal cortex in supporting fluid intelligence.

CORRELATIONS BETWEEN NONVERBAL INTELLIGENCE AND NERVE CONDUCTION VELOCITIES IN RIGHT-HANDED MALE AND FEMALE SUBJECTS

A neurological theory of intelligence suggesting a direct correlation between nerve conduction velocity and psychometric intelligence was tested. Cattell's Culture Fair Intelligence Test was used to asses the nonverbal intelligence (IQ) of subjects. The motor median nerve conduction velocity from right hand of males was positively correlated with IQ. In subjects with no familial sinistrality (FS–), the motor ulnar-nerve conduction velocity from the right and left hands of males negatively correlated with IQ; there were inverse correlations between IQ and nerve conduction velocity (motor median nerve from right, sensory median nerve from right and left) in females. In subjects with familial sinistrality (FS+), IQ directly correlated with nerve conduction velocity from motor median (right and left), sensory median (right), and motor ulnar (right) nerves, but only in males. The speed hypothesis and neurological theory of intelligence were not supported by these results, which, in contrast, emphasized the importance of sex and familial sinistrality in any theory of intelligence.

Correlations among Handedness, Eyedness, Monocular Shifts from Binocular Focal Point, and Nonverbal Intelligence in University Mathematics Students

Relationships among hand preference, nonverbal intelligence, and the monocular shifts of binocular focal point were studied in 33 men and 12 women university mathematics students. Ocular dominance was assessed with the Miles test. The monocular shift of binocular focal point for each eye was assessed with a modified Miles test. Hand preference was assessed on the Edinburg Handedness Inventory. Nonverbal intelligence was assessed with Cattell's Culture Fair Intelligence Test. In a prior study, the percentage of left-eye preference had been reported to be greater for mathematics students than for nonmathematics students. In the present study there were positive correlations between hand preference and the sum of the monocular shifts of two eyes. In addition, there was a negative correlation between nonverbal intelligence and the sum of the monocular shifts of two eyes. As these resultssuggest that the sum of the monocular shifts of two eyes may be related to mathematical ability and nonverbal intelligence, further research with a larger sample including non-mathematics students is needed.

Sex Differences in Verbal and Spatial Ability Reconsidered in Relation to Body Size Lung Volume, and Sex Hormones

Sex differences in verbal and nonverbal abilities were reconsidered in relation to bodily measures and sex hormones in Turkish university students. Perceptual-verbal ability was evaluated using As Test. To assess the nonverbal abilities, the mental rotation test and Cattell's Culture Fair Intelligence Test were used. As expected, the 53 women performed better than men on the As Test; 79 men had a higher mean than the 53 women on the mental rotation task; there was no sex difference on Cattell's IQ Test. Cattell IQs correlated only with tidal volume of lungs. Scores on the As Test did not show significant correlations with body size and lung capacities. Mental rotation was significantly correlated with height, weight, and lung volume. With covariates of height, weight, and vital capacity, sex differences in mental rotation completely disappeared, but the difference on the As Test increased while Cattell IQ remained sex-neutral. With testosterone as covariate, the sex difference on the As test increased but on the mental rotation task disappeared; Cattell IQ was sex-neutral. With covariates of estradiol and progesterone, sex differences on the As test disappeared; mental rotation scores and Cattell IQ were not influenced. Under a combined covariation of height, weight, and testosterone, sex differences in mental rotation reversed, women scoring better than men; after adding estradiol or progesterone instead of testosterone to this model, sex differences on mental rotation completely disappeared, but verbal ability and Cattell IQ were not changed. These results suggest that Cattell's Culture Fair Intelligence Test is unique in resistance to sex differences; perceptual-verbal ability was the most sex-specific mental trait but with dependence on estradiol; mental rotation, on the contrary, was least sex-specific, depending on body size, lung volume, sex hormones, and their combined actions, which explains women's better performance.

Vehicles of spatial ability

Spatial ability implies the generation, retention, retrieval, and transformation of visuo-spatial information. Factor analytic research has identified a broad array of spatial factors. Visualization (Vz) and Spatial relations (SR) are among the most cited. Dynamic spatial performance (DSP) has emerged in more recent times as a new strong candidate. However, there are some doubts about the existence of clear separate spatial factors. On the one hand, general spatial ability (Gv) has a substantial overlap with fluid reasoning (Gf). On the other hand, as Carroll's [Carroll, J. B. (1993). Human cognitive abilities: a survey of factor analytic studies. Cambridge: Cambridge University Press] survey notes, procedures of measurement are in need of considerable refinement. A battery of Vz, SR, and DSP spatial tests was applied in the present study to a sample of 105 undergraduates. The correlation matrix is analysed through a Schmid–Leiman hierarchical factor analysis, resulting in a powerful higher-order factor identified with Gv. First-order factors are shown as psychologically meaningless. Moreover, a confirmatory factor analysis demonstrates that a single endogenous factor, identified with Gv, predicts fairly well all the spatial markers. The correlation between the subjects' Gv factor scores and their scores in the Cattell's Culture Fair test shows a value of +0.6. Therefore, the study suggests that there is no clear separation among markers of some core spatial factors and that Gv strongly correlates with fluid ability (Gf).

Inducing Inductive Reasoning: Does It Transfer to Fluid Intelligence?

Based on a prescriptive theory of inductive reasoning, a training program to foster inductive reasoning has been developed. Children from 12 first-grade classes, mean age about 7 years, N = 279, participated in a training experiment. The children of 6 classes were trained to apply a strategy to reason inductively while the children of the remaining classes continued their regular classroom activities. It was expected that trained children would outperform the untrained children with respect to Raven's Coloured Progressive Matrices but not with respect to a vocabulary test, thus indicating convergent and discriminant or domain-specific training effects. Results confirmed this expectation. Moreover, it was expected that training would improve performance on the inductive subtests of Cattell's Culture Fair Test 1, but not influence subtests that did not involve inductive reasoning. Considerable transfer to both kinds of subtests was found on the immediate transfer task. However, with a delayed posttest 6 months later, the expected differential training effect could be observed. Finally, a LISREL model analysis confirmed the hypothesis that training children to reason inductively improved fluid but not crystallized intelligence.

Magnetic resonance imaging brain size/IQ relations in Turkish University students

The relation of IQ (Cattell's Culture Fair Intelligence Test) to brain size was studied in 103 right- and left-handed men and women at Atatürk University in eastern Turkey. Cerebral areas were measured on a midsagittal section of the brain using MRI. An overall correlation of 40 was found between MRI-measured total area and IQ thereby further supporting the IQ–brain size hypothesis. Additional analyses suggested that these results may need qualification. In men, only anterior cerebral area correlated with IQ. In women, total and posterior cerebral areas were correlated with IQ. Other results varied by handedness.

Correlations among scores on measures of field dependence-independence cognitive style, cognitive ability, and sustained attention.

The Children's Embedded Figures Test, the Rod and Frame Test to measure the field dependence-independence cognitive style, Cattell's Culture Fair Intelligence Tests to measure cognitive ability, and two cancellation tasks (Zazzo task and Bourdon task) to assess sustained attention were administered to 179 boys and 110 girls whose average age was 9.0 yr. Correlations between scores on measures of field dependence-independence and cognitive ability were moderated. Average correlations between scores on measures of field dependence-independence, cognitive ability, and measures of sustained attention was .23 for the Zazzo task and quite weak (.06) for the Bourdon task.

The Curvelinear Correlations Between the Total Testosterone Levels and Fluid Intelligence in Men and Women

The relationship between serum total testosterone (T) level and the fluid intelligence (Cattell's Culture Fair Intelligence Test) was studied in men and women. There was no significant difference between IQs of men and women. There was an inverse curvelinear relationship between IQ and T in women. The same was found also in men, but the declining part of the regression line at high T levels was not as pronounced as in women. It is concluded that T may be related to IQ, even in subjects exhibiting no sex difference in IQ tests; too low or too high T levels may be disadvantageous for the fluid intelligence, especially in women.