IQ on the rise: the Flynn effect in rural Kenyan children

Abstract - Multiple studies have documented significant IQ gains over time, a phenomenon labeled the Flynn effect. Data from 20 industrialized nations show massive IQ gains over time, most notably in culturally reduced tests like the Raven's Progressive Matrices. To our knowledge, however, this is the first study to document the Flynn effect in a rural area of a developing country. Data for this project were collected during two large studies in Embu, Kenya, in 1984 and 1998. Results strongly support a Flynn effect over this 14-year period, with the most significant gains found in Raven's matrices. Previously hypothesized explanations (e.g., improved nutrition; increased environmental complexity; and family, parental, school, and methodological factors) for the Flynn effect are evaluated for their relevance in this community, and other potential factors are reviewed. The hypotheses that resonate best with our findings are those related to parents' literacy, family structure, and children's nutrition and health.     

Resolving the IQ paradox: heterosis as a cause of the Flynn effect and other trends

IQ test scores have risen steadily across the industrialized world ever since such tests were first widely administered, a phenomenon known as the Flynn effect. Although the effect was documented more than 2 decades ago, there is currently no generally agreed-on explanation for it. The author argues that the phenomenon heterosis represents the most likely cause. Heterosis, often referred to as hybrid vigor, is a genetic effect that results from matings between members of genetically distinct subpopulations, such as has been occurring in human populations through the breakup of small, relatively isolated communities owing to urbanization and greater population mobility. In Part 1 of the article, empirical findings are listed that are consistent with a heterosis hypothesis but render other hypotheses either implausible or very difficult to test. In Part 2, a formal model of the process of heterosis is presented. The goal of the modeling is to develop a quantitatively rigorous method for estimating the potential contribution of heterosis in the Flynn effect, as well as trends observed in other heritable traits and conditions.     

Item-response theory modeling of IQ gains (the Flynn effect) on crystallized intelligence: Rodgers' hypothesis yes,Brand's hypothesis perhaps

Potential explanations for generational intelligence test score gains continue to be subject to intense debate and scrutiny in the scientific community. However, the explanatory value of some of the proposed causes remains difficult to determine, since only little empirical evidence is available. To clarify the role of two scarcely investigated theories accounting for the Flynn effect, this study set out to examine the role of changing test-taking behavior (Brand's hypothesis) and of a narrowing of the IQ ability distribution (Rodgers' hypothesis). Archival records of crystallized intelligence test performance over a time-span of 17 years of a large number of psychiatric inpatients and outpatients in Austria were investigated (N = 5445; 1978–94). This sample was particularly suitable to investigate our hypotheses since participants were under no pressure to perform which makes observed changes in test taking behavior attributable to personal style and ability rather than differential performance in pressure situations. Analytical approaches of both classical test theory and item response theory (IRT) yielded gains of 1.0 to 2.4 IQ points per decade. Test-taking behavior indicative of guessing and decreasing population IQ variability appeared to contribute both to IQ test score gains. IRT-based analyses showed that gains were largely preserved when controlling for highest educational qualification, while the test instrument showed measurement invariance between cohorts. However, IRT-based results also suggested that changes in test-taking behavior might not necessarily reflect increased guessing, but item drift instead. In all, this evidence emphasizes better performance of individuals of the lower tail of the IQ ability distribution in more recent years as one important contributing factor for generational IQ test score gains.     

The effect of a commercial game on children's block design scores on the WISC-R IQ test

Two experiments investigated the extent to which 10-year old children's scores on the WISC-R Block Design subtest were affected by prior experience with a specific commercial game that involved blocks and matching patterns. Experiment 1 found that 12 10-year old children who happened to have experience with the particular commercial game scored approximately three scaled score points higher on the WISC-R Block Design subtest than 24 matched children without game experience. In Experiment 2, 24 children who did not have prior experience with this particular commercial game were randomly assigned either to a Game condition (involving two 15-minute sessions with the game) or to a No-Game condition (which involved no further game experience). Children in the Game condition subsequently increased their WISC-R Block Design scores more than children in the No-Game condition. Taken together, the experiments indicate that relatively brief interactions with a commercial game can cause a significant improvement in children's performance on an IQ subtest.     

School-level genetic variation predicts school-level verbal IQ scores: Results from a sample of American middle and high schools

Research has consistently revealed that average IQ scores vary significantly across macro-level units, such as states and nations. The reason for this variation in IQ, however, has remained at the center of much controversy. One of the more provocative explanations is that IQ across macro-level units is the result of genetic differences, but empirical studies have yet to examine this possibility directly. The current study partially addresses this gap in the literature by examining whether average IQ scores across thirty-six schools are associated with differences in the allelic distributions of dopaminergic polymorphisms across schools. Analysis of data drawn from subjects (ages 12-19 years) participating in the National Longitudinal Study of Adolescent Health provides support in favor of this perspective, where variation in school-level IQ scores was predicted by school-level genetic variation. This association remained statistically significant even after controlling for the effects of race.     

"Panic": the impact of Le Bon's crowd psychology on U.S. military thought

The controversial crowd psychology of Gustave Le Bon has been both praised as an incisive contribution to social theory and also condemned as a doctrine of irrationality and mass manipulation associated with fascism. New archival documentation now demonstrates that Le Bon exercised significant influence on U.S. military thinking and practice through World War II. Army writings and officer training on morale, leadership, and battlefield psychology rested substantially on his theory of crowds, particularly regarding races and panic. Le Bon's racial psychology took on additional importance when the African-American 92 nd Infantry Division panicked during combat in Italy. This new evidence offers an excellent case study of the direct and enduring impact of a peculiar type of social psychology on the institutional culture of the army from the classrooms at the Army War College to the battlefield itself.     

The impact of perceived racial discrimination on the mental health of Asian American and Latino college students

The authors examined the impact of perceived racial discrimination on various mental health outcomes for Asian American and Latino college students within an emic and etic framework. Results indicate that Asian American and Latino college students experienced similar exposure and reactions to various kinds of discrimination. However, Latino students were more likely than Asian American students to have been accused of doing something wrong, such as cheating and breaking the law, and more likely to appraise these experiences as stressful. Asian Americans evidenced higher risk for trait anxiety. Regardless of ethnicity, perceived racial discrimination was associated with several negative mental health outcomes, including higher psychological distress, suicidal ideation, state anxiety, trait anxiety, and depression. Findings highlight the need to address discrimination across multiple social and professional settings and to understand the broad array of mental health outcomes.     

Presidential IQ, Openness, Intellectual Brilliance, and Leadership: Estimates and Correlations for 42 U.S. Chief Executives

Individual differences in intelligence are consistently associated with leader performance, including the assessed performance of presidents of the United States. Given this empirical significance, IQ scores were estimated for all 42 chief executives from George Washington to G. W. Bush. The scores were obtained by applying missing-values estimation methods (expectation-maximization) to published assessments of (a) IQ (Cox, 1926; n =  8), (b) Intellectual Brilliance (Simonton, 1986c; n =  39), and (c) Openness to Experience (Rubenzer & Faschingbauer, 2004; n =  32). The resulting scores were then shown to correlate with evaluations of presidential leadership performance. The implications for George W. Bush and his presidency were then discussed.     

The epidemiology of mental retardation: challenges and opportunities in the new millennium

There are a number of problems and challenges in relating the science of epidemiology to mental retardation (MR). These relate to how MR is defined and classified and how these definitions may change over time. These as well as other differences in ascertainment sources and methods need to be considered when comparing MR prevalence over time and place. On the other hand, advances in technology also provide new and efficient methods of data collection both by data linkage and by use of web-based methods to study rare diseases. While prevalence studies have not been individually reviewed, we have examined the range of data including recent studies relating to how prevalence differs according to age, gender, social class and ethnicity. Some problems with available etiological classification systems have been identified. Recent etiological studies, most of which use different classification systems, have been reviewed and explanations have been postulated to account for differences in results. Individual risk factors for MR are considered whilst the option of considering a population as opposed to a high risk strategy to MR prevention is raised. This might well involve improving the social milieu surrounding the occurrence of individual risk factors. The impact of biotechnological advances such as antenatal and neonatal screening and assisted reproduction on MR are discussed. The issue of how inequalities in access to technology may impact on case identification and even have the potential to further widen inequalities is raised. The importance of extending the use of epidemiological tools to study the social, health and economic burden of MR is also emphasized. However, in order to apply to MR the "prevention-intervention-research" cycle, which surely underpins all epidemiology, it is vital to ensure that the methodological challenges we raise are adequately addressed.     

The effect of acculturation and ethnic identification on consumer disidentification and consumption: An investigation of U.S. Hispanics

This study examines the antecedents and outcomes of consumer disidentification (CDI) among immigrants and the role that cultural change plays in affecting this consumer orientation. Specifically, it explores the effect of acculturation and ethnic identification on host nation sentiments (i.e., host nation identification, disidentification, and affinity) and how the latter influence CDI. Then, it assesses the effect of CDI on consumer behaviors including product quality judgments and willingness to buy products originating in the host country. Survey data from a convenience sample of 555 adults of Cuban and Puerto Rican origin, who live in the USA, confirm that disidentification with the host nation is the basis of CDI. Acculturation is the process through which disidentification with the host nation and the resulting CDI can be mitigated. However, ethnic identification shows inconsistencies in affecting consumers' sentiments toward the host nation and CDI. While CDI is negatively related to consumers' willingness to buy domestic products, it does not seem to affect consumers' willingness to buy domestic products through their product quality judgments. Practically, this study facilitates strategic marketing decisions that are related to the presentation of country‐of‐origin (COO) product attributes in marketing communication and branding campaigns. This study is one of the few empirical studies on CDI, and it focuses on COO effects of domestic rather than foreign products among subcultures within national boundaries. Understanding COO effects among subnational cultural consumers is of primary importance given the ever‐increasing ethnic diversification of consumer markets.     

Expanding variance and the case of historical changes in IQ means: a critique of Dickens and Flynn (2001)

The Flynn effect is the rise in mean IQ scores during the 20th century, amounting to about 0.33 IQ points per year. Many theoretical explanations have been proposed, though none are universally accepted. W. Dickens and J. R. Flynn's (2001) new approach explains the large IQ changes by means of recursive models of IQ growth. A salient feature of their models is that IQ phenotypes and their supportive environments are correlated; in addition, environmental effects can rebound on phenotypic IQ to increase or lower IQ. In this critique, the authors examine an empirical challenge to their models, which typically imply large changes in IQ variance. However, the historical rise in IQ mean level has not been accompanied by substantial variance changes, a finding inconsistent with the properties of the proposed model.     

The Bermond-Vorst Alexithymia Questionnaire: a measurement invariance examination among U.S. Anglos and U.S. Hispanics

The aim of this article is to assess the measurement invariance of the Bermond-Vorst Alexithymia Questionnaire (BVAQ) in U.S. Anglo (n = 490) and U.S. Hispanic ( n = 379) samples of college students. The BVAQ items demonstrated invariance of the factor loadings, the latent item intercepts, and unique factor variances. However, Hispanics had higher verbalizing scores and lower fantasizing scores on the latent variables. As a whole, the BVAQ requires additional testing and/or refinement for use with a Hispanic sample. Until such refinements, the authors recommend that the Toronto Alexithymia Scale-20 be used with U.S. Hispanic samples.     

MMPI-2 scores of Puerto Rican, Mexican, and U.S. Latino college students: a research note

In this brief report, we present MMPI-2 basic validity and clinical scale data of Latino-descent persons from Puerto Rico (n = 290), Mexico (n = 1,920), and the United States (n = 28). All were administered one of three Spanish translations of the MMPI-2. A review of the mean scores of these respective groups indicates similarities across all scales. Differences among these three groups, with the exception of the Mf scale (which is keyed to sex), were well within the one standard deviation band. More importantly, these findings are promising given the fact that three different translations of the MMPI-2 were applied.     

The impact of environmental noise on mealtime social interactions in a residential facility for persons with mental retardation

Four levels of environmental noise were experimentally manipulated during lunch and dinner in a residential living unit for 10 behaviorally disordered persons with mental retardation. During the highest noise conditions, there appeared to be some suppression of social interaction between these people, while interaction rates were uniformly higher during softer noise conditions. This effect was evident at both lunch and dinner. Staff members were less affected by the fluctuation in noise levels, although lunchtime staff engaged in more interactions with clients when both the radio and TV were played softly.     

The face of the state on the U.S.-Mexico border

In recent years, feminist geopolitics and the turns toward emotional and affective geography have resulted in new perspectives on theories of power, embodiment and subjectivity. Other recent trends have considered non-human objects as important for state theory, insofar as state practice often relies upon the force of objects in everyday life. This article works to bring together object-oriented and emotional geographies for a new perspective on the state. It does so by drawing on another theoretical tradition that has been less familiar for political geography: psychoanalytic theory. Findings from ethnographic research with residents living near the U.S.-Mexico border in Arizona help illuminate the presence and spectral circulation of what we call the “face of the state” as a psycho-emotional entity in everyday life for these residents. Surveillance objects enter the psyche through the face of the state, insofar as they are imagined and felt as a visual and embodied experience. The force of the object, then, extends beyond its own materiality and into the psycho-social dimensions of life through which state power operates, thereby empowering the border to gaze at the subject population in powerful new ways.     

The impact of national integration policies on prejudice and psychological well-being: The fundamental role of the clarity and coherence of integration policies

Recent advances in social psychological research have shown that national integration policies influence how immigrants are perceived and treated by the mainstream population. However, the processes by which these policies come to have an impact on prejudice and well-being of the general population are largely unknown. Moreover, past research has often relied on unrepresentative samples limiting generalizability. The present research proposes that when the national integration policies of a given society are perceived as clearly defined and coherent, they have a direct impact on the perceived cultural norm related to those national integration policies. In turn, the perceived cultural norm affects personal attitudes toward cultural norms (i.e., the degree to which individuals support a given policy), which influence the level of anti-immigrant prejudice as well as psychological well-being. Findings from two correlational studies with representative samples of the mainstream population conducted in France on the policy of secularism (N = 940) and in Québec on the policy of interculturalism (N = 912) supported the proposed theoretical model.