Deborah Finkel

Predicting Prejudice from Religious Fundamentalism and Right-Wing Authoritarianism: A Multiple-Regression Approach

In a study designed to investigate the respective roles of religious fundamentalism and right-wing authoritarianism as predictors of prejudice against racial minorities and homosexuals, participants (47 males, 91 females) responded to a series of questionnaire measures of these constructs. Data were analyzed using multiple regression. Consistent with previous research, authoritarianism was a significant and strong positive predictor of both forms of prejudice. With authoritarianism statistically controlled, however, fundamentalism emerged as a significant negative predictor of racial prejudice but a positive predictor of homosexual prejudice. In a second study, we conducted parallel multiple regressions using the correlations from two previously published studies. The Study I results were replicated exactly, except that fundamentalism was a nonsignificant predictor of homosexual prejudice. We interpret the results as evidence that Christian fundamentalism consists of a second major component other than authoritarianism - related to Christian belief content - that is inversely related to some forms of prejudice (including racial prejudice) but not others (e.g., homosexual prejudice).

Religious Fundamentalism as a Predictor of Prejudice: A Two-Component Model

The present study aims to determine whether the empirical relationship between religious fundamentalism and prejudice can be accounted for in terms of the mutually opposing effects of Christian orthodoxy and right-wing authoritarianism using multiple regression. Three separate samples (total n = 320) completed measures of religious fundamentalism, right-wing authoritarianism, Christian orthodoxy, ethnic prejudice, and homosexual prejudice. Consistent with previous research, fundamentalism (1) was essentially unrelated to ethnic prejudice when considered alone; (2) was positively related to ethnic prejudice when orthodoxy was statistically controlled; and (3) was negatively related to ethnic prejudice when authoritarianism was statistically controlled. Finally, when both authoritarianism and orthodoxy were controlled simultaneously, fundamentalism was again unrelated to prejudice, whereas orthodoxy was negatively related and authoritarianism positively related. In contrast, fundamentalism was a significant positive predictor of prejudice against gays and lesbians irrespective of whether authoritarianism and/or orthodoxy were statistically controlled.

Age changes in processing speed as a leading indicator of cognitive aging.

Bivariate dual change score models were applied to longitudinal data from the Swedish Adoption/Twin Study of Aging to compare the dynamic predictions of 2-component theories of intelligence and the processing speed theory of cognitive aging. Data from up to 5 measurement occasions covering a 16-year period were available from 806 participants ranging in age from 50 to 88 years at the first measurement wave. Factors were generated to tap 4 general cognitive domains: verbal ability, spatial ability, memory, and processing speed. Model fitting indicated no dynamic relationship between verbal and spatial factors, providing no support for the hypothesis that age changes in fluid abilities drive age changes in crystallized abilities. The results suggest that, as predicted by the processing speed theory of cognitive aging, processing speed is a leading indicator of age changes in memory and spatial ability, but not verbal ability.

Heritability of cognitive abilities in adult twins: Comparison of Minnesota and Swedish data

Cross-sectional reports suggest heritability of cognitive ability increases throughout adulthood. To investigate this hypothesis, quantitative genetic analyses were conducted on four measures of cognitive ability (verbal, spatial, perceptual speed, memory). Data from Minnesota and Swedish twin studies of aging were compared. Heritability estimates and the factor structure of cognitive abilities could be equated across younger twins (age, 27-50) and middle-aged twins (age, 50-65) from both studies, suggesting stability of heritability during adulthood. The heritability of 81% for a general cognitive factor confirmed earlier findings of high heritability in younger and middle-aged samples. Older Swedish twins (age, 65-85) demonstrated significantly lower heritability estimates for cognitive abilities (54%) and a significantly different factor structure of cognitive ability.

Latent growth curve analyses of accelerating decline in cognitive abilities in late adulthood.

Latent growth models were applied to data from the Swedish Adoption/Twin Study of Aging to discover if the rate of change in cognitive performance increased from middle age to later adulthood. The sample included 590 participants aged 44 to 88 years at first measurement. Data were gathered at 2 follow-up occasions at intervals of 3 years. Cognitive ability was assessed through 11 tests that tapped crystallized, fluid, memory, and spatial abilities and perceptual speed. Results indicated stability for measures of crystallized ability, linear age changes for many cognitive abilities, and a significant acceleration in linear decline after age 65 for measures with a large speed component. Gender differences were found only in mean level, not in rate of decline.

Sex differences and nonadditivity in heritability of the Multidimensional Personality Questionnaire Scales.

A sex-limitation model was applied to the Multidimensional Personality Questionnaire (MPQ) data from the Minnesota Twin Family Registry. The sample included 626 monozygotic (MZ) twin pairs, 517 same-sex dizygotic (DZ) twin pairs, and 114 opposite-sex DZ twin pairs ranging in age from 27 to 64 years (mean age = 37.8). In addition, whenever possible, family members of the twins were also assessed: 1,690 spouses, 495 parents, 322 siblings, and 535 offspring. The goals of the present investigation were to analyze the covariance matrices to determine whether (a) there was evidence for sex limitation of heritability of the MPQ scales and (b) there was evidence for nonadditive genetic influences on these scales. Significant sex differences in heritability were found for 3 of the scales: Alienation, Control, and Absorption. In addition, evidence for dominance was found for all scales except Traditionalism and Absorption.

Quantitative genetic analysis of latent growth curve models of cognitive abilities in adulthood

Though many cognitive abilities exhibit marked decline over the adult years, individual differences in rates of change have been observed. In the current study, biometrical latent growth models were used to examine sources of variability for ability level (intercept) and change (linear and quadratic effects) for verbal, fluid, memory, and perceptual speed abilities in the Swedish Adoption/Twin Study of Aging. Genetic influences were more important for ability level at age 65 and quadratic change than for linear slope at age 65. Expected variance components indicated decreasing genetic and increasing nonshared environmental variation over age. Exceptions included one verbal and two memory measures that showed increasing genetic and nonshared environmental variance. The present findings provide support for theories of the increasing influence of the environment with age on cognitive abilities.

Processing Speed and Longitudinal Trajectories of Change for Cognitive Abilities: The Swedish Adoption/Twin Study of Aging

In this manuscript, The Swedish Adoption/Twin Study of Aging (SATSA) is described. Although the study is a multidisciplinary program in gerontological genetics, the summary of findings focuses on the cognitive measures. In the second part of the manuscript, we investigate the role played by measures of processing speed in explaining the longitudinal trajectories of change for cognitive abilities and the genetic and environmental influences on those trajectories. When processing speed was regressed out of cognitive measures representing three cognitive domains (crystallized, fluid, and memory) and a general cognitive factor, the trajectory of decline was less severe. Quantitative genetic analyses indicated that environmental variance increases in late adulthood. A substantial portion of the genetic variance for these cognitive abilities was accounted for by genetic variance for speed. With increasing age, genetic variance associated with processing speed becomes a more prominent component of genetic variance for fluid abilities and for the general cognitive factor.

The Role of Occupational Complexity in Trajectories of Cognitive Aging Before and After Retirement

We examined the association between complexity of the main lifetime occupation and changes in cognitive ability in later life. Data on complexity of work with data, people, and things and on 4 cognitive factors (verbal, spatial, memory, and speed) were available from 462 individuals in the longitudinal Swedish Adoption/Twin Study of Aging. Mean age at the first measurement wave was 64.3 years (SD = 7.2), and 65% of the sample had participated in at least three waves of data collection. Occupational complexity with people and data were both correlated with cognitive performance. Individuals with more complex work demonstrated higher mean performance on the verbal, spatial, and speed factors. Latent growth curve analyses indicated that, after correcting for education, only complexity with people was associated with differences in cognitive performance and rate of cognitive change. Continued engagement as a result of occupational complexity with people helped to facilitate verbal function before retirement, whereas a previous high level of complexity of work with people was associated with faster decline after retirement on the spatial factor.

Longitudinal and Cross-Sectional Twin Data on Cognitive Abilities in Adulthood: The Swedish Adoption/Twin Study of Aging.

Cross-sequential methods of analysis, designed to separate age and cohort effects, were applied to data from the Swedish Adoption/Twin Study of Aging. Thirteen cognitive variables were collected at 3 times of measurement separated by 3-year intervals. Data were available from 85 individuals from monozygotic (MZ) pairs reared apart, 132 from MZ pairs reared together, 207 from dizygotic (DZ) pairs reared apart, and 178 from DZ pairs reared together (age range at first assessment: 41-84 years). Time x Cohort interactions were found for mean performance on 8 of the measures, revealing stable mean performance in the younger cohorts and longitudinal decreases in mean performance in the older cohorts. Cohort and time effects for total variance were mixed; little evidence was found for increases in variance with age. Age changes and cohort differences in genetic and environmental components of variance were test-specific; several Cohort x Time interactions attained significance. Heritability of the general cognitive ability factor showed significant longitudinal decreases over time in the older cohorts.