IQ Correlation Research Articles

9 The Correlation of IQ and Executive Function of VLBW and ELBW Preterm Children with Normal Early Development

AbstractObjective:Previous studies had shown that even with normal early development, preterm children at age six still have executive function deficits, including planning, cognitive flexibility, and nonverbal working memory. The present study aims to discuss further the correlation between IQ and EF of preterm children with different birthweight in order to clarify the potential influence of birthweight.Participants and Methods:The preterm children were recruited from the Regional Cohort Network for premature infants who were admitted to neonatal intensive care units. Inclusion criteria were their scores of Bayley Scales of Infant and Toddler Development, second or third edition at 12 and 24 months, and Wechsler Preschool and Primary Scale of Intelligence, Revised Edition at 5 years old were higher than 70. Meanwhile, their FSIQ of Wechsler Intelligence Scale for Children, Fourth Edition were higher than 85 at age 6. Exclusion criteria were visual impairment, hearing impairment, and cerebral palsy. There was a total of 251 preterm children recruited in the present study. Preterm children were then divided into very low birthweight (VLBW) and extremely low birth weight (ELBW) groups. The VLBW group included 183 preterm children, whose birthweight is between 1000-1500g, and gestational age is less than 37 weeks. The ELBW group included 68 preterm children, whose birthweight is less than 1000g and gestational age is less than 37 weeks. Four types of executive function were assessed. Inhibition was assessed through Comprehensive Nonverbal Attention Test Battery (CNAT), cognitive flexibility was assessed through Wisconsin Card Sorting Test (WCST), verbal working memory was assessed through the Longest Digit Span Forward (LDSB) index of Digit Span Subtest of Wechsler Intelligence Scale for Children-IV (WISC-IV), and nonverbal working memory was assessed through Knox's Cube Test (KCT), and planning ability was assessed through Tower of London (ToL). Data were analyzed with independent T-test and Pearson Correlation.Results:In VLBW preterm group, results showed that there were significant correlations (p<.05) between FSIQ and EF indexes in five out of six indexes of WCST, LDSB of Digit Span of WISC-IV, Backward score of Knox's Cube Test, and three out of six indexes of ToL. As to the CNAT, there was no index of CNAT that was significantly correlated with FSIQ in the VLBW preterm group. In ELBW preterm group, results showed that there were significant correlations (p<.05) between FSIQ and EF indexes in one out of five indexes of CNAT, one out of six indexes of WCST, Backward score of Knox's Cube Test, and two out of six indexes of ToL. And the LDSB of Digit Span of WISC-IV was not significantly correlated with FSIQ in ELBW preterm group.Conclusions:There were fewer EF indexes significantly correlated with FSIQ in ELBW preterm children with normal early development than VLBW preterm children with normal early development, suggesting that even with an IQ higher than 85, lower the birthweight, especially lower than 1000g, higher the EF performance should be concerned. Therefore, in the clinical setting, it is very important to assess the EF independently. And birthweight may be a crucial factor in preterm children's prefrontal cortex maturity.

The abilities of movie-watching functional connectivity in individual identifications and individualized predictions.

Quite a few studies have been performed based on movie-watching functional connectivity (FC). As compared to its resting-state counterpart, however, there is still much to know about its abilities in individual identifications and individualized predictions. To pave the way for appropriate usage of movie-watching FC, we systemically evaluated the minimum number of time points, as well as the exact functional networks, supporting individual identifications and individualized predictions of apparent traits based on it. We performed the study based on the 7T movie-watching fMRI data included in the HCP S1200 Release, and took IQ as the test case for the prediction analyses. The results indicate that movie-watching FC based on only 15 time points can support successful individual identifications (99.47%), and the connectivity contributed more to identifications were much associated with higher-order cognitive processes (the secondary visual network, the frontoparietal network and the posterior multimodal network). For individualized predictions of IQ, it was found that successful predictions necessitated 60 time points (predicted vs. actual IQ correlation significant at P < 0.05, based on 5,000 permutations), and the prediction accuracy increased logarithmically with the number of time points used for connectivity calculation. Furthermore, the connectivity that contributed more to individual identifications exhibited the strongest prediction ability. Collectively, our findings demonstrate that movie-watching FC can capture rich information about human brain function, and its ability in individualized predictions depends heavily on the length of fMRI scans.

Regional Cortical Thickness Correlates of Intellectual Abilities Differ in Children With Traumatic Brain Injury Versus Those With Orthopedic Injury in the Chronic Post-Injury Phase.

A decline in intellectual functioning (intelligence quotient [IQ]) is often observed following more severe forms of traumatic brain injury (TBI) and is a useful index for long-term outcome. Identifying brain correlates of IQ can serve to inform developmental trajectories of behavior in this population. Using magnetic resonance imaging (MRI), we examined the relationship between intellectual abilities and patterns of cortical thickness in children with a history of TBI or with orthopedic injury (OI) in the chronic phase of injury recovery. Participants were 47 children with OI and 58 children with TBI, with TBI severity ranging from complicated-mild to severe. Ages ranged from 8 to 14 years old, with an average age of 10.47 years, and an injury-to-test range of ∼1-5 years. The groups did not differ in age or sex. The intellectual ability estimate (full-scale [FS]IQ-2) was derived from a two-form (Vocabulary and Matrix Reasoning subtests) Wechsler Abbreviated Scale of Intelligence (WASI). MRI data were processed using the FreeSurfer toolkit and harmonized across data collection sites using neuroComBat procedures, while holding demographic features (i.e., sex, socioeconomic status [SES]), TBI status, and FSIQ-2 constant. Separate general linear models per group (TBI and OI) and a single interaction model with all participants were conducted with all significant results withstanding correction for multiple comparisons via permutation testing. Intellectual ability was higher (p < 0.001) in the OI group (FSIQ-2 = 110.81) than in the TBI group (FSIQ-2 = 99.81). In children with OI, bi-hemispheric regions, including the right pre-central gyrus and precuneus and bilateral inferior temporal and left occipital areas were related to IQ, such that higher IQ was associated with thicker cortex in these regions. In contrast, only cortical thickness in the right pre-central gyrus and bilateral cuneus positively related to IQ in children with TBI. Significant interaction effects were found in the bilateral temporal, parietal, and occipital lobes and left frontal regions, indicating that the relationship between IQ and cortical thickness differed between groups in these regions. Changes in cortical associations with IQ after TBI may reflect direct injury effects and/or adaptation in cortical structure and intellectual functioning, particularly in the bilateral posterior parietal and inferior temporal regions. This suggests that the substrates of intellectual ability are particularly susceptible to acquired injury in the integrative association cortex. Longitudinal work is needed to account for normal developmental changes and to investigate how cortical thickness and intellectual functioning and their association change over time following TBI. Improved understanding of how TBI-related cortical thickness alterations relate to cognitive outcome could lead to improved predictions of outcome following brain injury.

Intelligence, Personality and Tolerance of Ambiguity.

In this study, 3836 adults completed a personality test (the HPTI) and a multidimensional intelligence test (GIA). Two prominent theories that link personality traits to intelligence (compensation and investment) were tested. There were more sex differences in the personality traits than in the IQ scores. Correlational and regression analyses results provided little evidence for either theory but pointed to the role of tolerance of ambiguity as a consistently significant, positive correlate of IQ at both the facet and domain levels. The role of this neglected trait is discussed. Limitations of various aspects of this study and its implications are considered.

A Blueprint for Genetic Determinism

A Blueprint for Genetic Determinism

Correlation of Emotional Intelligence, Intelligence Quotient with academic performances of Dental students. A Cross Sectional study

Introduction: Several researchers academics have revealed in recent years that cognitive ability alone is insufficient to predict success,and that morals, talent, attitude, and behaviour all play a role. Salovey and Mayer investigated the reasons why many clever people failed in life more than a decade ago. Their research led to the identification of an intelligence subset known as emotional intelligence (EI). EI, as a sort of social intelligence, is more important than cognitive intelligence in terms of success.Objective: The aim of the present study was to determine the correlation of EQ and IQ with Academic performances.Methods: The present cross -sectional study was conducted in Baqai Dental College from July 2021- September 2021 after getting ethical approval from Ethical review board, Baqai Dental College. Dental students from 2nd year, 3rd year and Final year were invited to participate through census sampling technique. The study included all students from each class who were present on the day of data collection whereas those absent from each class were excluded from the study.Results: A total of 165 dental students participated in the study. Majority of the dental students fall in the domain of emotional awareness and management within 25-34 range of effective functioning. Frequency and percentages were also calculated for level of intelligence and 72 (43.6%) of the dental students scored 90-109 which is considered as Normal. Association of students marks from the last examination with IQ score was calculated and 48(39.7%) students with &lt;60% in the last examination fall in the Normal range of IQ. Correlation between EQ, IQ and academic performance was calculated and showed that a negative correlation was found between Academic performance and IQ.Conclusion: The present study concluded that emotional intelligence is positively correlated with academic performance and negatively correlated with IQ.KEYWORDS: Academic performance, Intelligent Quotient, Emotional awareness, Emotional intelligence, Emotional management, Relationship management

A Reevaluation of the 1990 “Minnesota Study of Twins Reared Apart” IQ Study

In 1990, Thomas J. Bouchard Jr. and colleagues published the widely cited 1990 “Minnesota Study of Twins Reared Apart” (MISTRA) Science IQ study. To arrive at the conclusion that “IQ is strongly affected by genetic factors,” Bouchard and colleagues omitted their control group reared-apart dizygotic twin (DZA) IQ score correlations. Near-full-sample correlations published after the study’s 2000 end point show that the reared-apart monozygotic twin (MZA) and DZA group IQ correlations did not differ at a statistically significant level, suggesting that the study failed the first step in determining that IQ scores are influenced by heredity. After bypassing the model-fitting technique they used in most non-IQ MISTRA studies, the researchers assumed that the MZA group IQ score correlation alone “directly estimates heritability.” This method was based on unsupported assumptions by the researchers, and they largely overlooked the confounding influence of cohort effects. Bouchard and colleagues then decided to count most environmental influences they did recognize as genetic influences. I conclude that the MISTRA IQ study failed to discover genetic influences on IQ scores and cognitive ability across the studied population, and that the study should be evaluated in the context of psychology’s replication problem.

Brain Functional Correlates of Intelligence Score in ADHD Based on EEG.

It has been shown that intelligence as a general mental ability is related to the structure and function of the brain regions. However, the specificity of these regional dependencies to the intelligence scores in the typical and atypical developed individuals needs to be well understood. In this study, we hypothesized that neural correlates of IQ should not have a fixed pattern rather they must follow a dynamic pattern to compensate for the functional deficits caused by a neurodevelopmental disorder. Therefore, electroencephalography (EEG) correlates of normal IQ in various subtypes of attention deficit hyperactive disorder (ADHD) were compared with a group of healthy controls. Sixty-three ADHD subjects comprising combined, inattentive, and hyperactive individuals diagnosed by a psychiatrist using structural clinical interview for DSM-V, and 46 healthy controls with similar normal IQ scores were recruited in this study. The subjects' EEG data were then recorded during an eye-closed resting condition. The subjects' intelligence level was measured by Raven's standard progressive matrices. Then, the association between IQ and the power of the EEG signal was computed in the conventional frequency bands. Subsequently, topographical representations of these associations were compared between the groups. Our results demonstrated that the association between IQ score and EEG power is not the same in various ADHD subtypes and healthy controls. This finding suggests a compensatory mechanism in ADHD individuals for changing the regional oscillatory pattern to maintain the IQ within a normal range.

Relationship between IQ and academic performance of medical students.

Objective: The objectives of this study were to find the correlation among the intelligence and academic achievement of MBBS students and to see if the correlation differs between boys and girls. Study Design: Cross Sectional Study. Setting: Ameer Ud Din Medical College / PGMI Lahore. Period: 1st January 2019 to 31st January 2019 Material &amp; Methods: A total of 100 second year MBBS students volunteered to participate (46 males and 54 females). Modified Wechsler Adult Intelligence Scale (WAIS) was used to access the IQ of students. Previous academic records of the students before their admission in medical college and written and oral test marks of second year MBBS students during the year were used for measuring academic achievements of students. The results were analyzed by spearmans correlation, Independent t test and Mann Whitney U test. Results: A statistically significant difference (p = 0.04) between IQ of boys and girls was found with males having mean IQ of 97.4±22.7 as compared to females 89.3±15.5. No significant difference was observed in academic achievements of male and female students. Correlation of IQ with academic achievements was also non-significant. Conclusion: Although males have higher IQ but it has no relationship with academic achievement of medical students. Hard work of the students with average or low IQ could be the reason that there was no difference in the academic achievement when they were compared with the students having higher IQ.

Examination of the genetic factors underlying the cognitive variability associated with neurofibromatosis type 1

PurposeNeurofibromatosis type 1 (NF1) is an autosomal dominant disorder associated with cognitive deficits. The NF1 cognitive phenotype is generally considered to be highly variable, possibly due to the observed T2-weighted hyperintensities, loss of heterozygosity, NF1-specific genetic modifiers, or allelic imbalance. MethodsWe investigated cognitive variability and assessed the contribution of genetic factors by performing a retrospective cohort study and a monozygotic twin case series. We included data of 497 children with genetically confirmed NF1 and an IQ assessment, including 12 monozygotic twin and 17 sibling sets. ResultsIndividuals carrying an NF1 chromosomal microdeletion showed significant lower full-scale IQ (FSIQ) scores than individuals carrying intragenic pathogenic NF1 variants. For the intragenic subgroup, the variability in cognitive ability and the correlation of IQ between monozygotic NF1 twin pairs or between NF1 siblings is similar to the general population. ConclusionsThe variance and heritability of IQ in individuals with NF1 are similar to that of the general population, and hence mostly driven by genetic background differences. The only factor that significantly attenuates IQ in NF1 individuals is the NF1 chromosomal microdeletion genotype. Implications for clinical management are that individuals with intragenic NF1 variants that score <1.5–2 SD below the mean of the NF1 population should be screened for additional causes of cognitive disability.

Overall cognitive profiles in patients with GLUT1 Deficiency Syndrome.

IntroductionGlucose Transporter Type I Deficiency Syndrome (GLUT1DS) classical symptoms are seizures, involuntary movements, and cognitive impairment but so far the literature has not devoted much attention to the last.MethodsIn our retrospective study involving 25 patients with established GLUT1DS diagnosis, we describe the cognitive impairment of these patients in detail and their response to the ketogenic diet in terms of cognitive improvement.ResultsWe outlined a specific cognitive profile where performance skills were more affected than verbal ones, with prominent deficiencies in visuospatial and visuomotor abilities. We demonstrated the efficacy of ketogenic diet (KD) on cognitive outcome, with particular improvement tin total and verbal IQ; we found that timing of KD introduction was inversely related to IQ outcome: the later the starting of KD, the lower the IQ, more notable nonverbal scale (verbal IQ correlation coefficient −0.634, p‐value = 0.015). We found a significant direct correlation between cognition and CSF/blood glucose ratio values: the higher the ratio, the better the cognitive improvement in response to diet (from T0–baseline evaluation to T1 on average 18 months after introduction of KD‐: TIQ correlation coefficient 0.592, p‐value = 0.26; VIQ correlation coefficient 0.555, p‐value = 0.039). Finally, we demonstrated that a longer duration of treatment is necessary to find an improvement in patients with “severely low ratio.”ConclusionOur results were consistent with the hypothesis that timing of the diet introduction is a predictive factor of cognitive outcome in these patients, confirming that earlier initiation of the diet may prevent the onset of all GLUT1DS symptoms: epilepsy, movement disorders, and cognitive impairment.

IQ profiles and clinical symptoms of Chinese school-aged boys with autism spectrum disorder

Background and objectiveThe cognitive abilities of individuals with autism spectrum disorder (ASD) vary widely, but studies have not yet examined Chinese school-aged boys with ASD in a systematic way.This study aims to explore the IQ profile of Chinese school-aged boys with ASD; and the correlation of IQ and related symptoms. MethodsThirty-one boys with ASD and forty-eight typically developing (TD) boys were examined using the WISC-IV Chinese version. The relationship between IQ index scores and ASD symptoms was explored. ResultsFor boys with ASD, in comparison to the TD Group, significantly lower scores were found for the Verbal Comprehension Index (VCI), Processing Speed Index (PSI) and Full Scale IQ (FSIQ). Examination of the Verbal IQ-Nonverbal IQ pattern across groups revealed differences between the ASD and the TD groups (x2=13.282, p=.001). For the ASD sample, a negative correlation was observed between all the Index scores and the Level & Consistency of Intellectual Response score. ConclusionsOur results indicated that Chinese school-aged boys with ASD show a different pattern of intellectual ability from their TD peers, with equivalent abilities in the PRI and WMI.

Peabody Picture Vocabulary Test: Proxy for Verbal IQ in Genetic Studies of Autism Spectrum Disorder.

This study assessed the utility of a brief assessment (the Peabody Picture Vocabulary Test-4th Edition; PPVT4) as a proxy for verbal IQ (VIQ) in large-scale studies of autism spectrum disorder (ASD). In a sample of 2,420 proband with ASD, PPVT4:IQ correlations were strong. PPVT4 scores were, on average, 5.46 points higher than VIQ; 79% of children had PPVT4 scores within one standard deviation (+/-15) of their VIQ and 90% were similarly classified as having abilities above or below 70 on both measures. Distributions of PPVT4 and VIQ by de novo mutation status were highly similar. These results strongly support the utility of PPVT4 as a proxy for VIQ in large-scale ASD studies, particularly for genetic investigations.

Small to medium magnitude Jensen effects on brain volume: A meta-analytic test of the processing volume theory of general intelligence

The processing volume theory of general intelligence predicts that brain volume imposes general constraints on the overall amounts of cortical substrate available for solving complex problems. Bigger brains contain more processing volume, hence can solve problems generally more efficiently than smaller brains. This theory predicts that the g loading of ability tests should substantially moderate the association between ability test performance and brain volume. This is tested with a bare-bones meta-analysis employing the method of correlated vectors (MCV) on the association between brain volume∗subtest correlations and subtest g loadings. The mean weighted vector correlation across four studies is ρ=0.07 (total N=246), increasing to ρ=0.35 when one potentially outlying study is removed. The magnitude of these Jensen effects suggests that g plays at best only a modest role in moderating the strength of the brain volume∗IQ correlation, contrary to predictions from the processing volume theory. This result is consistent with the observation that brain volume has low evolutionary lability compared with g, suggesting that recent evolutionary changes in population levels of g may have occurred largely independently of overall changes in brain volume.

The effectiveness of working memory training – points to consider for future research

Abstract Working memory training (WMT) has recently become one of the most debated issues in the field of cognitive psychology. Since working memory (WM) is considered a strong correlate of IQ, numerous researchers have been trying to increase the latter by training the former. Proven effectiveness of working memory training could lead to its application in the therapy of many cognitive impairments. WMT could be also used as a tool of improving cognitive functioning of healthy subjects. However, almost every publication claiming to provide evidence for achieving one of above mentioned objectives has been criticised, mostly because of methodological shortcomings. The aim of my presentation is to extract potential sources of inconsistencies existing between the authors of meta-analysis and reviews of WMT research. For this reason I take a closer look at results and conclusions of several meta-analysis and reviews. As a result I point few indications that should be taken into consideration in future studies on WMT effectiveness.

What Can an Adoption Study Tell Us About the Effect of Prenatal Environment on a Trait?

Adoption studies provide possibilities for estimating the extent to which prenatal environmental events account for individual differences on a trait. Correlations with birth mothers but not adoptive mothers suggest the presence of genetic or prenatal environmental effects; higher correlations with birth mothers than with birth fathers suggest the presence of the latter. Changes over time may also be relevant. The concepts involved are illustrated with parent-child IQ correlations from the Texas and Colorado Adoption Projects.

The effect of intelligence on financial development: A cross-country comparison

We assess the correlations between intelligence and financial development in 123 countries using data averages from 2000–2010. Cognitive human capital is measured in terms of IQ (Lynn and Vanhanen's IQ measures), cognitive ability (Rindermann's combination of psychometric and student assessment test measures) and cognitive skills (Hanushek's student assessment test measures), while financial development is appreciated both from financial intermediary and stock market development perspectives. Short-term financial measures are private and domestic credits whereas long-term financial indicators include: stock market capitalization, stock market value traded and turnover ratio. The following findings are established based on standardized correlations. (1) For the nexus with private credit, the positive correlations of IQ and cognitive ability are broadly similar, while that of cognitive skills is lower relative to cognitive ability. (2) The correlation between intelligence and other financial variables are broadly similar, but for the higher degree of association with stock market value traded. (3) The underlying findings are broadly confirmed in terms of sign of correlation, though the magnitude of correlation is higher (lower) with the addition of social capital or ethnic fractionalization (institutions or income). (4) When continents are excluded to control for extreme effects, baseline results are confirmed and the following on order of continental importance in financial development is established in increasing magnitude: Americas, Europe, Oceania, Africa and Asia.

Neuroanatomical Diversity of Corpus Callosum and Brain Volume in Autism: Meta-analysis, Analysis of the Autism Brain Imaging Data Exchange Project, and Simulation

BackgroundPatients with autism have been often reported to have a smaller corpus callosum (CC) than control subjects. MethodsWe conducted a meta-analysis of the literature, analyzed the CC in 694 subjects of the Autism Brain Imaging Data Exchange project, and performed computer simulations to study the effect of different analysis strategies. ResultsOur meta-analysis suggested a group difference in CC size; however, the studies were heavily underpowered (20% power to detect Cohen’s d = .3). In contrast, we did not observe significant differences in the Autism Brain Imaging Data Exchange cohort, despite having achieved 99% power. However, we observed that CC scaled nonlinearly with brain volume (BV): large brains had a proportionally smaller CC. Our simulations showed that because of this nonlinearity, CC normalization could not control for eventual BV differences, but using BV as a covariate in a linear model would. We also observed a weaker correlation of IQ and BV in cases compared with control subjects. Our simulations showed that matching populations by IQ could then induce artifactual BV differences. ConclusionsThe lack of statistical power in the previous literature prevents us from establishing the reality of the claims of a smaller CC in autism, and our own analyses did not find any. However, the nonlinear relationship between CC and BV and the different correlation between BV and IQ in cases and control subjects may induce artifactual differences. Overall, our results highlight the necessity for open data sharing to provide a more solid ground for the discovery of neuroimaging biomarkers within the context of the wide human neuroanatomical diversity.

The Effect of Intelligence on Financial Development: A Cross-Country Comparison

We assess the correlations between intelligence and financial development in 123 countries using data averages from 2000-2010. Human capital is measured in terms of IQ, cognitive ability & cognitive skills, while financial development is appreciated both from financial intermediary and stock market development perspectives. Short-term financial measures are private and domestic credits whereas long-term financial indicators include: stock market capitalization, stock market value traded and turnover ratio. The following findings are established. (1) With respect to private credit, the positive correlations of IQ and cognitive ability are broadly similar while that of cognitive skills is substantially higher in terms of magnitude. (2) The correlation between intelligence and other financial variables are broadly similar. (3) The underlying findings are broadly confirmed in terms of sign of correlation, though the magnitude of correlation is higher (lower) with the addition of social capital or ethnic fractionalization (institutions or income). (4) When continents are excluded to control for extreme effects, baseline results are confirmed and the following on order of continental importance in financial development is established in increasing magnitude: Africa, Americas, Oceania, Europe & Asia.

The genetic correlation between height and IQ: shared genes or assortative mating?

Traits that are attractive to the opposite sex are often positively correlated when scaled such that scores increase with attractiveness, and this correlation typically has a genetic component. Such traits can be genetically correlated due to genes that affect both traits (“pleiotropy”) and/or because assortative mating causes statistical correlations to develop between selected alleles across the traits (“gametic phase disequilibrium”). In this study, we modeled the covariation between monozygotic and dizygotic twins, their siblings, and their parents (total N = 7,905) to elucidate the nature of the correlation between two potentially sexually selected traits in humans: height and IQ. Unlike previous designs used to investigate the nature of the height–IQ correlation, the present design accounts for the effects of assortative mating and provides much less biased estimates of additive genetic, non-additive genetic, and shared environmental influences. Both traits were highly heritable, although there was greater evidence for non-additive genetic effects in males. After accounting for assortative mating, the correlation between height and IQ was found to be almost entirely genetic in nature. Model fits indicate that both pleiotropy and assortative mating contribute significantly and about equally to this genetic correlation.