scispace - formally typeset
Search or ask a question
Author

Eric Turkheimer

Bio: Eric Turkheimer is an academic researcher from University of Virginia. The author has contributed to research in topics: Personality disorders & Twin study. The author has an hindex of 56, co-authored 194 publications receiving 11847 citations. Previous affiliations of Eric Turkheimer include University of Texas at Austin & Case Western Reserve University.


Papers
More filters
Journal ArticleDOI
TL;DR: Results demonstrate that the proportions of IQ variance attributable to genes and environment vary nonlinearly with SES, and suggest that in impoverished families, 60% of the variance in IQ is accounted for by the shared environment, and the contribution of genes is close to zero; in affluent families, the result is almost exactly the reverse.
Abstract: Scores on the Wechsler Intelligence Scale for Children were analyzed in a sample of 7-year-old twins from the National Col- laborative Perinatal Project. A substantial proportion of the twins were raised in families living near or below the poverty level. Biometric analyses were conducted using models allowing for components attrib- utable to the additive effects of genotype, shared environment, and non- shared environment to interact with socioeconomic status (SES) measured as a continuous variable. Results demonstrate that the proportions of IQ variance attributable to genes and environment vary nonlinearly with SES. The models suggest that in impoverished families, 60% of the vari- ance in IQ is accounted for by the shared environment, and the contri- bution of genes is close to zero; in affluent families, the result is almost exactly the reverse.

1,194 citations

Journal ArticleDOI
TL;DR: Twin studies offer a useful methodological shortcut, but do not show that genes are more fundamental than environments, andotype is in fact a more systematic source of variability than environment.
Abstract: Behavior genetics has demonstrated that genetic variance is an important component of variation for all behavioral outcomes, but variation among families is not. These results have led some critics of behavior genetics to conclude that heritability is so ubiquitous as to have few consequences for scientific understanding of development, while some behavior genetic partisans have concluded that family environment is not an important cause of developmental outcomes. Both views are incorrect. Genotype is in fact a more systematic source of variability than environment, but for reasons that are methodological rather than substantive. Development is fundamentally nonlinear, interactive, and difficult to control experimentally. Twin studies offer a useful methodological shortcut, but do not show that genes are more fundamental than environments.

787 citations

Journal ArticleDOI
TL;DR: The relationship between working memory and intelligence, the apparent contradiction between strong heritability effects on IQ, whether a general intelligence factor could arise from initially largely independent cognitive skills, the relation between self-regulation and Cognitive skills, and the effects of stress on intelligence are reported.
Abstract: We review new findings and new theoretical developments in the field of intelligence New findings include the following: (a) Heritability of IQ varies significantly by social class (b) Almost no genetic polymorphisms have been discovered that are consistently associated with variation in IQ in the normal range (c) Much has been learned about the biological underpinnings of intelligence (d) "Crystallized" and "fluid" IQ are quite different aspects of intelligence at both the behavioral and biological levels (e) The importance of the environment for IQ is established by the 12-point to 18-point increase in IQ when children are adopted from working-class to middle-class homes (f) Even when improvements in IQ produced by the most effective early childhood interventions fail to persist, there can be very marked effects on academic achievement and life outcomes (g) In most developed countries studied, gains on IQ tests have continued, and they are beginning in the developing world (h) Sex differences in aspects of intelligence are due partly to identifiable biological factors and partly to socialization factors (i) The IQ gap between Blacks and Whites has been reduced by 033 SD in recent years We report theorizing concerning (a) the relationship between working memory and intelligence, (b) the apparent contradiction between strong heritability effects on IQ and strong secular effects on IQ, (c) whether a general intelligence factor could arise from initially largely independent cognitive skills, (d) the relation between self-regulation and cognitive skills, and (e) the effects of stress on intelligence

765 citations

Journal ArticleDOI
TL;DR: Self-harmers had more symptoms of several personality disorders than non-self- Harmers, and their performance across measures suggested that anxiety plays a prominent role in their psychopathology.
Abstract: OBJECTIVE: Research on deliberate self-harm (intentionally injuring oneself without suicidal intent) has focused on clinical and forensic populations. Studying only these populations, which typically have serious psychopathology, may lead to inflated estimates of the association between self-harm and psychiatric disorder, as well as of the prevalence of deliberate self-harm. The present study investigated the prevalence and correlates of deliberate self-harm in a large group of nonclinical subjects. METHOD: Participants were 1,986 military recruits, 62% of whom were men, who were participating in a study of peer assessment of personality traits and pathology. Individuals who did and did not report a history of self-harm were compared on measures of personality and psychopathology. RESULTS: Approximately 4% of the participants reported a history of deliberate self-harm. Compared with participants without a history of deliberate self-harm, self-harmers scored higher on self- and peer-report measures of bord...

754 citations

Journal ArticleDOI
TL;DR: The authors review the conceptual foundations of nonshared environment, with emphasis on distinctions between components of environmental variance and causal properties of environmental events and between the effective and objective aspects of the environment.
Abstract: When genetic similarity is controlled, siblings often appear no more alike than individuals selected at random from the population. Since R, Plomin and D. Daniels' seminal 1987 review, it has become widely accepted that the source of this dissimilarity is a variance component called nonshared environment. The authors review the conceptual foundations of nonshared environment, with emphasis on distinctions between components of environmental variance and causal properties of environmental events and between the effective and objective aspects of the environment. A statistical model of shared and nonshared environmental variables is developed. A quantitative review shows that measured nonshared environmental variables do not account for a substantial portion of the nonshared variability posited by biometric studies of behavior. Other explanations of the preponderance of nonshared environmental variability are suggested. Why Are Children in the Same Family So Different? In what may have been the most influential article ever written in the field of developmental behavior genetics, Plomin and Daniels (1987) reviewed evidence that a substantial portion of the variability in behavioral outcomes could not be explained by the additive effects of genotype or the environmental influences of families. They suggested that this residual term, which they called the nonshared environment, had been neglected by environmentally oriented researchers who assumed that the most important mechanisms of environmental action involved familial variables, like socioeconomic status and parenting styles, that are shared by siblings raised in the same home and serve to make siblings more similar to each other. Indeed, Plomin and Daniels argued, once genetic relatedness has been taken into account, siblings seem to be hardly more similar than children chosen at random from the

514 citations


Cited by
More filters
Journal Article
TL;DR: For the next few weeks the course is going to be exploring a field that’s actually older than classical population genetics, although the approach it’ll be taking to it involves the use of population genetic machinery.
Abstract: So far in this course we have dealt entirely with the evolution of characters that are controlled by simple Mendelian inheritance at a single locus. There are notes on the course website about gametic disequilibrium and how allele frequencies change at two loci simultaneously, but we didn’t discuss them. In every example we’ve considered we’ve imagined that we could understand something about evolution by examining the evolution of a single gene. That’s the domain of classical population genetics. For the next few weeks we’re going to be exploring a field that’s actually older than classical population genetics, although the approach we’ll be taking to it involves the use of population genetic machinery. If you know a little about the history of evolutionary biology, you may know that after the rediscovery of Mendel’s work in 1900 there was a heated debate between the “biometricians” (e.g., Galton and Pearson) and the “Mendelians” (e.g., de Vries, Correns, Bateson, and Morgan). Biometricians asserted that the really important variation in evolution didn’t follow Mendelian rules. Height, weight, skin color, and similar traits seemed to

9,847 citations

Book
08 Sep 2020
TL;DR: A review of the comparative database from across the behavioral sciences suggests both that there is substantial variability in experimental results across populations and that WEIRD subjects are particularly unusual compared with the rest of the species – frequent outliers.
Abstract: Behavioral scientists routinely publish broad claims about human psychology and behavior in the world's top journals based on samples drawn entirely from Western, Educated, Industrialized, Rich, and Democratic (WEIRD) societies. Researchers - often implicitly - assume that either there is little variation across human populations, or that these "standard subjects" are as representative of the species as any other population. Are these assumptions justified? Here, our review of the comparative database from across the behavioral sciences suggests both that there is substantial variability in experimental results across populations and that WEIRD subjects are particularly unusual compared with the rest of the species - frequent outliers. The domains reviewed include visual perception, fairness, cooperation, spatial reasoning, categorization and inferential induction, moral reasoning, reasoning styles, self-concepts and related motivations, and the heritability of IQ. The findings suggest that members of WEIRD societies, including young children, are among the least representative populations one could find for generalizing about humans. Many of these findings involve domains that are associated with fundamental aspects of psychology, motivation, and behavior - hence, there are no obvious a priori grounds for claiming that a particular behavioral phenomenon is universal based on sampling from a single subpopulation. Overall, these empirical patterns suggests that we need to be less cavalier in addressing questions of human nature on the basis of data drawn from this particularly thin, and rather unusual, slice of humanity. We close by proposing ways to structurally re-organize the behavioral sciences to best tackle these challenges.

6,370 citations

Journal ArticleDOI
TL;DR: A review of the distinction between various forms of intraclass correlation coefficients (ICC) can be found in this article, followed by a discussion of the relationship between the two types of ICCs.
Abstract: Although intraclass correlation coefficients (ICCs) are commonly used in behavioral measurement, psychometrics, and behavioral genetics, procedures available for forming inferences about ICCs are not widely known. Following a review of the distinction between various forms of the ICC, this article p

5,858 citations

BookDOI
01 Nov 2000
TL;DR: From Neurons to Neighborhoods as discussed by the authors presents the evidence about "brain wiring" and how children learn to learn to speak, think, and regulate their behavior, and examines the effect of the climate-family, child care, community-within which the child grows.
Abstract: How we raise young children is one of today's most highly personalized and sharply politicized issues, in part because each of us can claim some level of "expertise." The debate has intensified as discoveries about our development-in the womb and in the first months and years-have reached the popular media. How can we use our burgeoning knowledge to assure the well-being of all young children, for their own sake as well as for the sake of our nation? Drawing from new findings, this book presents important conclusions about nature-versus-nurture, the impact of being born into a working family, the effect of politics on programs for children, the costs and benefits of intervention, and other issues. The committee issues a series of challenges to decision makers regarding the quality of child care, issues of racial and ethnic diversity, the integration of children's cognitive and emotional development, and more. Authoritative yet accessible, From Neurons to Neighborhoods presents the evidence about "brain wiring" and how kids learn to speak, think, and regulate their behavior. It examines the effect of the climate-family, child care, community-within which the child grows.

5,295 citations

Journal ArticleDOI
TL;DR: A meta-analysis of the results shows that early math skills have the greatest predictive power, followed by reading and then attention skills, while measures of socioemotional behaviors were generally insignificant predictors of later academic performance.
Abstract: Using 6 longitudinal data sets, the authors estimate links between three key elements of school readiness--school-entry academic, attention, and socioemotional skills--and later school reading and math achievement In an effort to isolate the effects of these school-entry skills, the authors ensured that most of their regression models control for cognitive, attention, and socioemotional skills measured prior to school entry, as well as a host of family background measures Across all 6 studies, the strongest predictors of later achievement are school-entry math, reading, and attention skills A meta-analysis of the results shows that early math skills have the greatest predictive power, followed by reading and then attention skills By contrast, measures of socioemotional behaviors, including internalizing and externalizing problems and social skills, were generally insignificant predictors of later academic performance, even among children with relatively high levels of problem behavior Patterns of association were similar for boys and girls and for children from high and low socioeconomic backgrounds

4,384 citations