Finding the g-factor in brain structure using the method of correlated vectors

It is unclear whether brain mechanisms underlying human intelligence are distributed throughout the brain or mainly concentrated in the frontal lobes. Data are inconsistent possibly due, at least in part, to the different ways the construct of intelligence is measured. Here we apply the method of correlated vectors to determine how the general factor of intelligence (g) is related to regional gray matter and white matter volumes. This is a re-analysis of an earlier study showing regional gray matter and white matter volume is correlated to Full Scale IQ (FSIQ). However, it is well-known that FSIQ taps several cognitive abilities and skills in addition to g. The results now show that the g factor accounts for several but not all FSIQ/gray matter correlations distributed throughout the brain and these areas may differ for young and older adults.     

小学优等生与学习不良学生智力特征的比较研究

本研究运用 WISC-CR研究了小学阶段一、三、五年级优生与学习不良儿童在智力水平与智力结构上的异同。研究结果表明 :1优生与学习不良儿童在智力水平上有十分显著的差异 ,优生的平均智商为 1 2 0 .1 ,学习不良儿童的平均智商为 97.4;2优生在操作分量表与语言分量表上的得分比较均匀 ,但学习不良儿童的操作智商显著地优于语言智商 ;3优生与学习不良儿童在智力结构上也不尽相同 ,优生在词汇、积木、类同等分测验上的得分高 ,在算术、背数、排列等分测验上的得分较低 ;学习不良儿童在拼图、译码、填图、词汇等分测验上的得分较高 ,在常识、算术、背数等上的得分较低。     

Implicit theories of intelligence and IQ test performance in adolescents with Generalized Anxiety Disorder

During the past decade, several studies have reported positive effects of cognitive-behavioral therapy (CBT) in the treatment of children and adolescents with mental disorders. One of the most important CBT interventions is to teach children and adolescents to challenge negative thoughts that lead to maladjusted behaviors. Based on the implicit theories of intelligence framework, the main purpose of this study was to test whether an incremental theory manipulation could be used to affect IQ test performance in adolescents with Generalized Anxiety Disorder (GAD). Results showed that patients demonstrated enhanced IQ performance and experienced less state anxiety when they were exposed to an incremental theory of intelligence manipulation. Our findings suggest that incremental theory manipulation provides a useful cognitive strategy for addressing school-related anxiety in adolescents with mental disorders such as GAD.     

Expanding the g-nexus: Further evidence regarding the relations among national IQ, religiosity and national health outcomes

The current study seeks to better understand how religiosity and health are positioned within the g-nexus. Specifically, the degree to which differences in average IQ across nations is associated with differences in national religiosity (i.e., belief rate) and national health statistics independent of differences in national wealth is examined. Consistent with expectations, results show that, independent of national wealth and belief rate, IQ has a positive influence on national health as indicated by fertility rate, infant mortality rate, maternal mortality rate, and deaths due to HIV/AIDS, and life expectancy. Additionally, as hypothesized, IQ and belief rate interacted to influence reproductive health (i.e., fertility rate, infant- and maternal mortality). Specifically, high IQ acts as a buffer against the negative effects of belief rate; when IQ is high belief rate has no effect, but when IQ is low belief rate has a strong negative effect. The pattern of findings from this study, combined with previous research, serve to confirm that general cognitive ability (i.e., the g-factor) is an important and central node within a larger nexus of psychological and social variables. Theoretical and epidemiological implications are discussed.     

IQ, skin color, crime, HIV/AIDS, and income in 50 U.S. states

In 50 U.S. states, we found a positive manifold across 11 measures including IQ, skin color, birth rate, infant mortality, life expectancy, HIV/AIDS, violent crime, and state income with the first principal component accounting for 33% of the variance (median factor loading = .34). The correlation with a composite of total violent crime was higher with skin color (r = .55), a more biologically influenced variable than with GDP (r = −.17), a more culturally influenced variable. These results corroborate and extend those found at the international level using INTERPOL crime statistics and at the county, provincial, and state levels within countries using local statistics. We interpret the cross-cultural consistency from an evolutionary life history perspective in which hierarchically organized traits culminate in a single, heritable, super-factor. Traits need to be genetically organized to meet the trials of life—survival, growth, and reproduction. We discuss brain size and the g nexus as central to understand individual and group differences and we highlight melanin and skin color as a potentially important new life history variable.     

智力分布纵论

智力分布本是心理测量的一项重要内容,但众多心理测量教材往往对此论述不足。因此,本文详述有关智力分布的4个论题:(1)正确理解智商组别的组距和组限的表述;(2)4种智力中等标准之比较;(3)3种智力超常标准之比较;(4)如何计算智力分布类别的理论百分比。     

Estimating state IQ: Measurement challenges and preliminary correlates

The purpose of this study is threefold. First, an estimate of state IQ is derived and its strengths and limitations are considered. To that end, an indicator of downward bias in estimating state IQ is provided. Two preliminary causal models are offered that predict state IQ. These models were found to be highly predictive of state IQ, yielding multiple R's of 0.83 and 0.89. Second, the extent to which state IQ predicts state outcome variables (e.g., gross state product, health, violent crime, and government effectiveness) is estimated. State IQ shows positive correlations with gross state product, health, and government effectiveness and negative correlations with violent crime. These results are consistent with the extent to which IQ predicts outcomes at the level of the individual. Third, a research agenda is provided for improving estimates of state IQ, identifying factors that cause differences in state IQ, and delineating the role of IQ in predicting important variables.     

IQ stability: the relation between child and young adult intelligence test scores in low-birthweight samples

The stability of IQ from childhood to adulthood in low-birthweight subjects was measured in two independent samples with follow-up intervals of approximately 14 and 9.5 years. In both samples, intelligence was assessed with the WISC at a mean age of 9.5. Twenty-six subjects were retested with the WAIS at a mean age of 23.5, and 78 subjects with the BPP (the Danish Military Draft Board Intelligence Test) at the age of 19.1. Both samples obtained childhood and adult test scores below the expected means. For the Wechsler Verbal, Performance and Full-Scale IQs, the stability quotients were 0.86, 0.86, and 0.89 in the WAIS sample, and the retest correlations for the three IQs with the BPP score were 0.66, 0.65, and 0.74. Thus, the majority of children showed stable patterns of intellectual development from middle childhood to young adulthood.     

Correlation between general factors for personality and cognitive skills in the National Merit twin sample

General factors of personality (based on the California Psychological Inventory) and cognitive skill (the National Merit Scholarship Qualifying Test selection score) were correlated .284 in a sample of 490 monozygotic and 317 dizygotic twin pairs. The correlation was partitioned into genetic, and shared and unshared environmental sources: approximately 39%, 50% and 11%, respectively. The results offered some support to a theory that such a correlation may reflect evolutionary trends, although questions remained about the role of nonadditive genetic variance and the nature of the selection involved.     

A brief explanation of the Chu bamboo slips Hengxian

The discovery of Hengxian and the formation of the category of hengxian are an important recapitulation and creative integration of the theory of the ontological Dao (Tao) in the Pre-Qin period. The cosmology of “self-creating and self-functioning” in Hengxian and the theory of “self-creating and self-evolving” in Liezi and Zhuangzi can be mutually interpreted. It indicates that the theory of transformation of qi entered a quite mature state in the Warring States Period. __________ Translated from Qilu Xuekan 齐鲁学刊 (Qilu Academic Journal), 2005 (1) by Yan Xin     

On the Dao in the Commentary of the Book of Change

The existence of the Dao 道 (the Way), according to the Yizhuan 易传 (the Commentary), is something intangible. The connotation of the Dao is the law of change caused by the interaction between yin and yang. The main functions of the Dao are “to change” and “to generate”. The intangible refers to the law of change caused by the interaction between yin and yang, and the law is expressed by the divinatory symbolic system (卦爻符号, the trigrams or hexagrams). It is through the unique permutation of yin and yang lines of a trigram or hexagram that the law of change is explained as a universal model uniting celestial, terrestrial and human laws. The symbolic system is used to express the universal nature of continual generation of life. __________ Translated from Zhongguo Zhexue Shi 中国哲学史 (History of Chinese Philosophy), 2005(4) by Yun Yufen     

A review of the worst performance rule: Evidence, theory, and alternative hypotheses

This paper reviews evidence, theory, and alternative hypotheses for the worst performance rule (WPR), which states that on multitrial cognitive tasks, worst performance trials predict general intelligence (g) better than best performance trials. A review of the relevant evidence indicates that the WPR has been found for a variety of participants, tasks, and measures. A review of relevant theories reveals that the WPR appears to be related to cognitive factors (e.g., lapses in working memory) as well as biological factors (e.g., individual differences in neural oscillations). A review of alternative hypotheses shows that the WPR cannot be attributed to statistical or data artifacts such as outliers, unreliable measurement, or variance compression. The preponderance of evidence supports the hypothesis that the WPR holds for cognitive tasks high in g saturation but not for cognitive tasks low in g saturation. The paper ends with a call for research on the causes of the WPR and for research on the correlates of best performance.     

County-level IQ and fertility rates: A partial test of Differential-K theory

Human intelligence (IQ) correlates with a number of important life outcomes ranging from mortality and morbidity to social rank and status. Noticeably absent from the literature, however, has been a unifying framework from which to examine why IQ should correspond to so many seemingly disparate outcomes. Rushton’s Differential-K theory represents a theoretical perspective capable of accounting for the role of IQ in understanding human flourishing. We tested predictions suggested by Differential-K theory by examining the association between IQ at the aggregate level and two life-history variables: parental investment and fertility rates. Our results provide tentative support for some of the predictions of Differential-K theory.     

Jensen Effects and African/Coloured/Indian/White differences on Raven's Standard Progressive Matrices in South Africa

A test is made to determine whether various ethnic group differences on tests of cognitive performance in South Africa are like the Black/White differences in the United States in being positively associated with a tests' g loadings, where g is the general factor of intelligence. A non-parametric re-analysis is made of data from 1056 White, 1063 Indian, 778 mixed-race “Coloured,” and 1093 Black 14 year olds on the Raven's Standard Progressive Matrices Test in South Africa, given without time limits by Owen (1992) [Personality and Individual Differences, 13, 149]. The new analyses showed that the more highly correlated an item was with g, the more it predicted the White/Indian/Coloured/African differences on the test (Spearman's rhos from 0.35 to 0.85; all Ps<0.01). The effects remained regardless of which group g was extracted from. Understanding group differences around the world requires new research on the nature and nurture of g.     

Investigating the predictive roles of working memory and IQ in academic attainment

There is growing evidence for the relationship between working memory and academic attainment. The aim of the current study was to investigate whether working memory is simply a proxy for IQ or whether there is a unique contribution to learning outcomes. The findings indicate that children’s working memory skills at 5 years of age were the best predictor of literacy and numeracy 6 years later. IQ, in contrast, accounted for a smaller portion of unique variance to these learning outcomes. The results demonstrate that working memory is not a proxy for IQ but rather represents a dissociable cognitive skill with unique links to academic attainment. Critically, we find that working memory at the start of formal education is a more powerful predictor of subsequent academic success than IQ. This result has important implications for education, particularly with respect to intervention.     

On the heritability of inspection time and its covariance with IQ: a twin study

Using the classical twin design, this study investigates the influence of genetic factors on the large phenotypic variance in inspection time (IT), and whether the well established IT–IQ association can be explained by a common genetic factor. Three hundred ninety pairs of twins (184 monozygotic, MZ; 206 dizygotic, DZ) with a mean age of 16 years participated, and 49 pairs returned approximately 3 months later for retesting. As in many IT studies, the pi figure stimulus was used and IT was estimated from the cumulative normal ogive. IT ranged from 39.4 to 774.1 ms (159±110.1 ms) with faster ITs (by an average of 26.9 ms) found in the retest session from which a reliability of .69 was estimated. Full-scale IQ (FIQ) was assessed by the Multidimensional Aptitude Battery (MAB) and ranged from 79 to 145 (111±13). The phenotypic association between IT and FIQ was confirmed (−.35) and bivariate results showed that a common genetic factor accounted for 36% of the variance in IT and 32% of the variance in FIQ. The maximum likelihood estimate of the genetic correlation was −.63. When performance and verbal IQ (PIQ & VIQ) were analysed with IT, a stronger phenotypic and genetic relationship was found between PIQ and IT than with VIQ. A large part of the IT variance (64%) was accounted for by a unique environmental factor. Further genetic factors were needed to explain the remaining variance in IQ with a small component of unique environmental variance present. The separability of a shared genetic factor influencing IT and IQ from the total genetic variance in IQ suggests that IT affects a specific subcomponent of intelligence rather than a generalised efficiency.     

中国哲学中身心关系的几种形态

Ancient Chinese philosophers were inclined to preserve the doctrine of a unified body and mind rather than to engage in a discussion on the separation of the two. In addition, most traditional Chinese philosophers stressing in particular the function of mind. Based on the tradition of believing in the concept of qi, they traced the cause of their spiritual activities to the natural effect of the qi. The modalities display a phenomenological characteristic that looks at mental activities lightly, and examines language and action as a natural revelation of material force, qi. __________ Translated from Beijing Daxue Xuebao 北京大学学报 (Journal of Peking University), 2005, (5): 5–14