The Sequenced Inventory of Communication Development: An Adoption Study of                 Two and Three-year olds

The etiology of individual differences in communicative development is explored using data from 226 adoptive and 224 nonadoptive families in the Colorado Adoption Project. Scores from the Sequenced Inventory of Communication Development (SICD) (Hedrick, Prather, & Tobin, 1975) in 2-and 3-year-old children are compared to concurrent and longitudinal measures of verbal and general cognitive ability and to verbal and general cognitive ability in their parents. Sibling correlations for the SICD and cross-correlations for the SICD and I.Q. in related and unrelated pairs are also examined. Sibling correlations indicate that performance on the SICD is genetically influenced and that the relationship between the SICD and I.Q. at 2 and 3 years of age is in part genetically mediated. At 2 and 3 years of age, SICD scores are related to parental intelligence and verbal ability and this relationship is partially determined by family environmental factors at both ages. At 3 years of age, the SICD scores of adopted children correlates significantly with their biological mothers' general cognitive ability.

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Nature, Nurture, and Cognitive Development from 1 to 16 Years: A Parent-Offspring Adoption Study

Psychological Science ◽

10.1111/j.1467-9280.1997.tb00458.x ◽

1997 ◽

Vol 8 (6) ◽

pp. 442-447 ◽

Cited By ~ 130

Author(s):

Robert Plomin ◽

David W. Fulker ◽

Robin Corley ◽

John C DeFries

Keyword(s):

Cognitive Development ◽

Cognitive Ability ◽

Middle Childhood ◽

Cognitive Abilities ◽

Verbal Ability ◽

Adoptive Parents ◽

Childhood And Adolescence ◽

Adopted Children ◽

Adoption Study ◽

Biological Parents

Children increasingly resemble their parents in cognitive abilities from infancy through adolescence Results obtained from a 20-year longitudinal adoption study of 245 adopted children and their biological and adoptive parents, as well as 245 matched nonadoptive (control) parents and offspring, show that this increasing resemblance is due to genetic factors Adopted children resemble their adoptive parents slightly in early childhood but not at all in middle childhood or adolescence In contrast, during childhood and adolescence, adopted children become more like their biological parents, and to the same degree as children and parents in control families Although these results were strongest for general cognitive ability and verbal ability similar results were found for other specific cognitive abilities—spatial ability, speed of processing, and recognition memory These findings indicate that within this population, genes that stably affect cognitive abilities in adulthood do not all come into play until adolescence and that environmental factors that contribute to cognitive development are not correlated with parents' cognitive ability

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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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Race and General Cognitive Ability: The Myth of Diminishing Returns to Education

Psychological Science ◽

10.1111/1467-9280.00026 ◽

1998 ◽

Vol 9 (2) ◽

pp. 139-142 ◽

Cited By ~ 22

Author(s):

Joel Myerson ◽

Mark R. Rank ◽

Fredric Q. Raines ◽

Mark A. Schnitzler

Keyword(s):

Cognitive Ability ◽

Racial Differences ◽

College Education ◽

Educational Process ◽

General Cognitive Ability ◽

Diminishing Returns ◽

Using Data ◽

The Impact ◽

Positive Effect ◽

Educational Careers

The impact of education on racial differences in general cognitive ability was assessed using data from the National Longitudinal Survey of Youth. To control for attrition during the educational process, we compared the scores of individuals who ultimately attained the same level of education but who were tested at different points in their educational careers. Multiple regression analyses revealed that education can have a strong positive effect on cognitive ability in both whites and blacks. Whites benefited more from education than blacks during the high school years, but blacks benefited much more than whites from a college education, substantially narrowing the gap between the races. These findings contradict the hypothesis that racial differences in intelligence are relatively immutable, in part because of the diminishing returns from increases in education.

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Attitudes Toward Presidential Candidates in the 2012 and 2016 American Elections: Cognitive Ability and Support for Trump

Social Psychological and Personality Science ◽

10.1177/1948550618800494 ◽

2018 ◽

Vol 10 (7) ◽

pp. 924-934 ◽

Cited By ~ 2

Author(s):

Yoav Ganzach ◽

Yaniv Hanoch ◽

Becky L. Choma

Keyword(s):

Cognitive Ability ◽

Verbal Ability ◽

Party Affiliation ◽

Or Education ◽

Presidential Candidates ◽

American Elections ◽

Using Data ◽

Election Studies ◽

The Relationship ◽

Negative Predictor

Using data from the American National Election Studies, we investigated the relationship between cognitive ability and attitudes toward and actual voting for presidential candidates in the 2012 and 2016 U.S. presidential elections (i.e., Romney, Obama, Trump, and Clinton). Isolating this relationship from competing relationships, results showed that verbal ability was a significant negative predictor of support and voting for Trump (but not Romney) and a positive predictor of support and voting for Obama and Clinton. By comparing within and across the election years, our analyses revealed the nature of support for Trump, including that support for Trump was better predicted by lower verbal ability than education or income. In general, these results suggest that the 2016 U.S. presidential election had less to do with party affiliation, income, or education and more to do with basic cognitive ability.

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Sex Differences in Childhood Associations between DNA Markers and General Cognitive Ability

Journal of Individual Differences ◽

10.1027/1614-0001.28.3.161 ◽

2007 ◽

Vol 28 (3) ◽

pp. 161-164 ◽

Cited By ~ 1

Author(s):

Rosalind Arden ◽

Nicole Harlaar ◽

Robert Plomin

Keyword(s):

Sex Differences ◽

Single Nucleotide Polymorphisms ◽

Cognitive Ability ◽

Dna Markers ◽

Community Sample ◽

Nucleotide Polymorphisms ◽

General Cognitive Ability ◽

Single Nucleotide ◽

The Difference

Abstract. An association between intelligence at age 7 and a set of five single-nucleotide polymorphisms (SNPs) has been identified and replicated. We used this composite SNP set to investigate whether the associations differ between boys and girls for general cognitive ability at ages 2, 3, 4, 7, 9, and 10 years. In a longitudinal community sample of British twins aged 2-10 (n > 4,000 individuals), we found that the SNP set is more strongly associated with intelligence in males than in females at ages 7, 9, and 10 and the difference is significant at 10. If this finding replicates in other studies, these results will constitute the first evidence of the same autosomal genes acting differently on intelligence in the two sexes.

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