Is there G beyond g? (Is there genetic influence on specific cognitive abilities independent of genetic influence on general cognitive ability?)

Little is known about the importance of genetic effects on individual differences in cognitive abilities late in life. We present the first report from the Swedish Adoption/Twin Study of Aging (SATSA) for cognitive data, including general cognitive ability and 13 tests of specific cognitive abilities. The adoption/twin design consists of identical twins separated at an early age and reared apart (46 pairs), identical twins reared together (67 pairs), fraternal twins reared apart (100 pairs), and fraternal twins reared together (89 pairs); average age was 65 years. Heritability of general cognitive ability in these twins was much higher (about 80%) than estimates typically found earlier in life (about 50%). Consistent with the literature, heritabilities of specific cognitive abilities were lower than the heritability of general cognitive ability but nonetheless substantial. Average heritabilities for verbal, spatial, perceptual speed, and memory tests were, respectively, 58%, 46%, 58%, and 38%.

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The Genetic and Environmental Relationship Between General and Specific Cognitive Abilities in Twins Age 80 and Older

Psychological Science ◽

10.1111/1467-9280.00035 ◽

1998 ◽

Vol 9 (3) ◽

pp. 183-189 ◽

Cited By ~ 26

Author(s):

Stephen A. Petrill ◽

Robert Plomin ◽

Stig Berg ◽

Boo Johansson ◽

Nancy L. Pedersen ◽

...

Keyword(s):

Cognitive Ability ◽

Cognitive Abilities ◽

Memory Performance ◽

General Cognitive Ability ◽

Speed Of Processing ◽

Processing Abilities ◽

Genetic And Environmental Factors ◽

Performance Results ◽

The Relationship ◽

Specific Cognitive Abilities

In the first twin study of the old-old, individuals 80 years old and older, we examined the relationship between general and specific cognitive abilities from a genetic perspective. That is, we examined the extent to which genetic and environmental factors influence major group factors of cognitive abilities, independent of general cognitive ability. As part of the OctoTwin project in Sweden, general and specific cognitive abilities were assessed in 52 monozygotic and 65 same-sex dizygotic twin pairs 80 years old and older using a battery of seven tests that assess verbal, spatial, speed-of-processing, and memory performance. Results suggest that genetic effects associated with general cognitive ability (g) account for the correlation between g and verbal, spatial, and speed-of-processing abilities. No genetic influences were found for these specific cognitive abilities separate from g. In contrast, memory ability appears to be more distinct genetically from g than are other cognitive abilities. Comparison with younger samples suggests that cognitive abilities relating to speed of processing may be genetically dedifferentiated in the old-old.

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Spurious correlations in research on the effects of specific cognitive abilities

10.31234/osf.io/knc4t ◽

2021 ◽

Author(s):

Kimmo Sorjonen ◽

Bo Melin

Keyword(s):

Cognitive Ability ◽

Cognitive Abilities ◽

Test Scores ◽

Verbal Ability ◽

Positive Association ◽

Longitudinal Survey ◽

The Other ◽

General Cognitive Ability ◽

Math Ability ◽

Specific Cognitive Abilities

Studies on the effect of non-g ability residuals have often employed double adjustment for general cognitive ability (g), as they have calculated the ability residuals adjusting for g and then calculated the effect of the non-g residuals while adjusting for g. The present simulations demonstrate that the double adjustments may result in spurious negative associations between the non-g residual on one cognitive ability, e.g. verbal ability, and variables with a positive association with another ability, e.g. SAT math and math ability. In analyses of the 1997 National Longitudinal Survey of Youth (NLSY97), the negative associations between non-g residuals on verbal and math ability and aptitude test scores on the other ability vanished when not double adjusting for g. This indicates that the observed negative associations may be spurious and not due to differential investment of time and effort in one ability at the expense of the other ability, as suggested in the literature. Researchers of the effects of specific abilities are recommended to validate their findings and interpretations with analyses not double adjusting for g.

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Similarity in General Cognitive Ability, Creativity, and Cognitive Style in a Sample of Adolescent Russian Twins

Acta geneticae medicae et gemellologiae twin research ◽

10.1017/s000156600000252x ◽

1992 ◽

Vol 41 (1) ◽

pp. 65-72 ◽

Cited By ~ 14

Author(s):

E.L. Grigorenko ◽

M.C. LaBuda ◽

A.S. Carter

Keyword(s):

Soviet Union ◽

Cognitive Ability ◽

Cognitive Abilities ◽

Cognitive Styles ◽

Twin Studies ◽

General Cognitive Ability ◽

Fraternal Twin ◽

The Soviet Union ◽

Russian Adolescent ◽

Specific Cognitive Abilities

AbstractData on five tests of general and specific cognitive abilities, cognitive styles, and creativity, obtained from members of 60 identical and 63 fraternal Russian adolescent twin pairs, are presented. All tests are adaptations of standardized instruments widely used outside of the Soviet Union. Identical and fraternal twin correlations for general cognitive ability yielded a lower estimate of heritability (0.29) than generally found in other countries worldwide (0.52) although the twin correlations themselves are fairly comparable to figures from other countries and cultures — 0.83 and 0.69 for Russian identical and fraternal twin pairs, respectively, vs 0.86 and 0.60 for non-Russian identical, and fraternal twin pairs. Twin correlations for other cognitive-related abilities assessed were also comparable to correlations obtained outside the Soviet Union with the exception of creativity which yielded higher within-pair resemblance than reported in previous twin studies.

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What Is IQ? Life Beyond “General Intelligence”

Current Directions in Psychological Science ◽

10.1177/0963721419827275 ◽

2019 ◽

Vol 28 (2) ◽

pp. 189-194 ◽

Cited By ~ 16

Author(s):

Kristof Kovacs ◽

Andrew R. A. Conway

Keyword(s):

Cognitive Ability ◽

Cognitive Abilities ◽

Latent Trait ◽

Cognitive Activity ◽

General Intelligence ◽

General Cognitive Ability ◽

Neural Basis ◽

Standard View ◽

Different Content ◽

Recent Account

For more than a century, the standard view in the field of human intelligence has been that there is a “general intelligence” that permeates all human cognitive activity. This general cognitive ability is supposed to explain the positive manifold, the finding that intelligence tests with different content all correlate. Yet there is a lack of consensus regarding the psychological or neural basis of such an ability. A recent account, process-overlap theory, explains the positive manifold without proposing general intelligence. As a consequence of the theory, IQ is redefined as an emergent formative construct rather than a reflective latent trait. This implies that IQ should be interpreted as an index of specific cognitive abilities rather than the reflection of an underlying general cognitive ability.

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Brain structure and cognitive ability in healthy aging: a review on longitudinal correlated change

Reviews in the Neurosciences ◽

10.1515/revneuro-2018-0096 ◽

2019 ◽

Vol 31 (1) ◽

pp. 1-57 ◽

Cited By ~ 15

Author(s):

Jessica Oschwald ◽

Sabrina Guye ◽

Franziskus Liem ◽

Philippe Rast ◽

Sherry Willis ◽

...

Keyword(s):

Cognitive Ability ◽

Brain Structure ◽

Cognitive Abilities ◽

Medial Temporal Lobe ◽

Healthy Aging ◽

Cross Sectional ◽

Healthy Older Adults ◽

Memory Processing ◽

Theory Of Aging ◽

Specific Cognitive Abilities

Abstract Little is still known about the neuroanatomical substrates related to changes in specific cognitive abilities in the course of healthy aging, and the existing evidence is predominantly based on cross-sectional studies. However, to understand the intricate dynamics between developmental changes in brain structure and changes in cognitive ability, longitudinal studies are needed. In the present article, we review the current longitudinal evidence on correlated changes between magnetic resonance imaging-derived measures of brain structure (e.g. gray matter/white matter volume, cortical thickness), and laboratory-based measures of fluid cognitive ability (e.g. intelligence, memory, processing speed) in healthy older adults. To theoretically embed the discussion, we refer to the revised Scaffolding Theory of Aging and Cognition. We found 31 eligible articles, with sample sizes ranging from n = 25 to n = 731 (median n = 104), and participant age ranging from 19 to 103. Several of these studies report positive correlated changes for specific regions and specific cognitive abilities (e.g. between structures of the medial temporal lobe and episodic memory). However, the number of studies presenting converging evidence is small, and the large methodological variability between studies precludes general conclusions. Methodological and theoretical limitations are discussed. Clearly, more empirical evidence is needed to advance the field. Therefore, we provide guidance for future researchers by presenting ideas to stimulate theory and methods for development.

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Cortical Structure and Cognition in Infants and Toddlers

Cerebral Cortex ◽

10.1093/cercor/bhz126 ◽

2019 ◽

Vol 30 (2) ◽

pp. 786-800 ◽

Cited By ~ 5

Author(s):

Jessica B Girault ◽

Emil Cornea ◽

Barbara D Goldman ◽

Shaili C Jha ◽

Veronica A Murphy ◽

...

Keyword(s):

Cognitive Ability ◽

Cortical Thickness ◽

Cognitive Abilities ◽

Maternal Education ◽

General Cognitive Ability ◽

Infants And Toddlers ◽

Cognitive Domains ◽

Cortical Structure ◽

Cortical Regions ◽

Visual Reception

ABSTRACTCortical structure has been consistently related to cognitive abilities in children and adults, yet we know little about how the cortex develops to support emergent cognition in infancy and toddlerhood when cortical thickness (CT) and surface area (SA) are maturing rapidly. In this report, we assessed how regional and global measures of CT and SA in a sample (N = 487) of healthy neonates, 1-year-olds, and 2-year-olds related to motor, language, visual reception, and general cognitive ability. We report novel findings that thicker cortices at ages 1 and 2 and larger SA at birth, age 1, and age 2 confer a cognitive advantage in infancy and toddlerhood. While several expected brain–cognition relationships were observed, overlapping cortical regions were also implicated across cognitive domains, suggesting that infancy marks a period of plasticity and refinement in cortical structure to support burgeoning motor, language, and cognitive abilities. CT may be a particularly important morphological indicator of ability, but its impact on cognition is relatively weak when compared with gestational age and maternal education. Findings suggest that prenatal and early postnatal cortical developments are important for cognition in infants and toddlers but should be considered in relation to other child and demographic factors.

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Physical frailty and decline in general and specific cognitive abilities: the Lothian Birth Cohort 1936

Journal of Epidemiology & Community Health ◽

10.1136/jech-2019-213280 ◽

2019 ◽

Vol 74 (2) ◽

pp. 108-113 ◽

Cited By ~ 3

Author(s):

Catharine Gale ◽

Stuart J Ritchie ◽

John M Starr ◽

Ian J Deary

Keyword(s):

Cognitive Ability ◽

Birth Cohort ◽

Processing Speed ◽

Cognitive Abilities ◽

General Cognitive Ability ◽

Visuospatial Ability ◽

Physical Frailty ◽

Cognitive Domains ◽

Memory Processing ◽

Lothian Birth Cohort

BackgroundPhysical frailty is associated with many adverse outcomes including disability, chronic disease, hospitalisation, institutionalisation and death. It is unclear what impact it might have on the rate of normal cognitive ageing. We investigated whether physical frailty was related to initial level of, and change in, cognitive abilities from age 70 to 79 years.MethodParticipants were 950 members of the Lothian Birth Cohort 1936. Physical frailty was assessed at age 70 years using the Fried criteria. Cognitive function was assessed at ages 70, 73, 76 and 79 years. We used linear regression to examine cross-sectional and prospective associations between physical frailty status at age 70 years and factor score estimates for baseline level of and change in four cognitive domains (visuospatial ability, memory, processing speed and crystallised ability) and in general cognitive ability.ResultsPhysical frailty, but not prefrailty, was associated with lower baseline levels of visuospatial ability, memory, processing speed and general cognitive ability after control for age, sex, education, depressive symptoms, smoking and number of chronic illnesses. Physical frailty was associated with greater decline in each cognitive domain: age-adjusted and sex-adjusted standardised regression coefficients (95% CIs) were: −0.45 (−0.70 to –0.20) for visuospatial ability, −0.32 (−0.56 to –0.07) for memory, −0.47 (−0.72 to −0.22) for processing speed, −0.43 (−0.68 to –0.18) for crystallised ability and −0.45 (−0.70 to –0.21) for general cognitive ability. These associations were only slightly attenuated after additional control for other covariates.ConclusionPhysical frailty may be an important indicator of age-related decline across multiple cognitive domains.

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Associations between total MRI-visible small vessel disease burden and domain-specific cognitive abilities in a community-dwelling older-age cohort

10.1101/2021.02.02.21250986 ◽

2021 ◽

Author(s):

OKL Hamilton ◽

SR Cox ◽

L Ballerini ◽

ME Bastin ◽

J Corley ◽

...

Keyword(s):

Cognitive Ability ◽

Processing Speed ◽

Verbal Memory ◽

Cognitive Abilities ◽

Small Vessel Disease ◽

Full Range ◽

Community Dwelling ◽

Small Vessel ◽

General Cognitive Ability ◽

Vessel Disease

AbstractCerebral small vessel disease (SVD) is a leading cause of vascular cognitive impairment, however the precise nature of SVD-related cognitive deficits, and their associations with structural brain changes, remain unclear. We combined computational volumes and visually-rated MRI markers of SVD to quantify total SVD burden, using data from the Lothian Birth Cohort 1936 (n=540; age:72.6±0.7 years). We found negative associations between total SVD burden and general cognitive ability (standardised β: −0.363; 95%CI: [−0.49, −0.23]; p(FDR)<0.001), processing speed (−0.371 [−0.50, −0.24]; p(FDR)<0.001), verbal memory (−0.265; [−0.42, −0.11]; p(FDR)=0.002), and visuospatial ability (−0.170; [−0.32, −0.02]; p(FDR)=0.029). Only the association between SVD burden and processing speed remained after accounting for covariance with general cognitive ability (−0.325; [−0.61, −0.04]; p(FDR)=0.029). This suggests that SVD’s association with poorer processing speed is not driven by, but is independent of its association with poorer general cognitive ability. Tests of processing speed may be particularly sensitive to the cognitive impact of SVD, but all major cognitive domains should be tested to determine the full range of SVD-related cognitive characteristics.

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Blood-based epigenome-wide analyses of cognitive abilities

10.1101/2021.05.24.21257698 ◽

2021 ◽

Author(s):

Daniel L. McCartney ◽

Robert F Hillary ◽

Daniel Trejo-Banos ◽

Danni Alisha Gadd ◽

Rosie M Walker ◽

...

Keyword(s):

Dna Methylation ◽

Individual Differences ◽

Association Study ◽

Cognitive Ability ◽

Cognitive Functions ◽

Cognitive Abilities ◽

Variance Components ◽

General Cognitive Ability ◽

Variance Components Analysis ◽

Components Analysis

We present a blood-based epigenome-wide association study and variance-components analysis of cognitive functions (n=9,162). Individual differences in DNA methylation (DNAm) accounted for up to 41.5% of the variance in cognitive functions; together, genetic and epigenetic markers accounted for up to 70.4% of the variance. A DNAm predictor accounted for 3.4% and 4.5% (P≤9.9x10-6) of the variance in general cognitive ability, independently of a polygenic score, in two external cohorts.

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