Age-related differences in face processing: a meta-analysis of three functional neuroimaging experiments.

Differences between young and old adults in brain activity, measured with positron emission tomography, were examined during three face processing experiments: episodic memory, working memory, and degraded face perception. Each experiment contained an easy face matching condition and a more difficult processing condition. Young adults showed greater activity in bilateral prefrontal cortex during the memory tasks, compared to face matching, but no difference in prefrontal activity between degraded and nondegraded perception. Older adults, on the other hand, had greater prefrontal activity in both memory and degraded perceptual tasks compared to matching. This suggests that increased prefrontal activity is task-specific in young adults, but, in old adults, is a more general response to increased cognitive effort or need for resources. These data are consistent with the dedifferentiation hypothesis of aging, and suggest a possible neural mechanism for this dedifferentiation, such that dependence on prefrontal activity across a greater number of tasks could also increase the amount of covariance across these tasks.     

The determinants of employee absenteeism: An empirical test of a causal model*

LISREL estimates of the parameters of a causal model of absenteeism are reported for a sample of 425 full-time employees of a 327-bed medical centre. The model modifies and extends the conceptual framework of Steers & Rhodes (1978) and includes routinization, centralization, pay, distributive justice, work involvement, role ambiguity, conflict and overload, kinship responsibility, organizational permissiveness, job satisfaction, job involvement, organizational commitment, health status and alcohol involvement as the determinants of absenteeism. Based on self-report measures of absence frequency, significant positive direct effects of kinship responsibility, organizational permissiveness, role ambiguity and alcohol involvement, and negative direct effects of centralization, pay and job satisfaction yielded an R² for absenteeism of 21.6. Job satisfaction completely mediated the effects of routinization and work involvement, and partially mediated the effects of centralization and role ambiguity.     

Gender differences in temperament: a meta-analysis

The authors used meta-analytical techniques to estimate the magnitude of gender differences in mean level and variability of 35 dimensions and 3 factors of temperament in children ages 3 months to 13 years. Effortful control showed a large difference favoring girls and the dimensions within that factor (e.g., inhibitory control: d = -.41, perceptual sensitivity: d = -0.38) showed moderate gender differences favoring girls, consistent with boys' greater incidence of externalizing disorders. Surgency showed a difference favoring boys, as did some of the dimensions within that factor (e.g., activity: d = 0.33, high-intensity pleasure: d = 0.30), consistent with boys' greater involvement in active rough-and-tumble play. Negative affectivity showed negligible gender differences.     

Twin-singleton differences in intelligence: a meta-analysis

Since the emergence of twin studies in the 1920s, time and again the question of possible twin-singleton differences in intelligence has been posed. This study addressed the issue through a meta-analysis of published studies on this theme. Twins on the average seem to have lower IQs than singletons. The best estimate for this group difference is 4.2 IQ points (less than one-third of a standard deviation), with a great divide between study outcomes of less vs more recent birth cohorts (5.1 vs 0.5 IQ points, respectively). The evidence is based on studies from six countries (including population-based ones of entire birth cohorts), a massive database (comparisons of more than 30,000 twins with nearly 1.6 million singletons), a variety of intelligence tests, and birth cohorts spanning most of the 20th century, but, for the most part, on an age range limited to children and adolescents. The effect shows considerable between-study heterogeneity but appears robust (fail-safe N calculations), not due to influential individual studies (sensitivity analysis) or publication bias, was present since the very first published studies (cumulative meta-analysis), and appears generalizable across sex, zygosity, and other intelligence domains beyond the verbal. There are insufficient data as to whether the effect persists over the lifespan, exists as well within families, or has ceased in recent birth cohorts of highly developed countries (Denmark and The Netherlands). Likely causes of the effect appear to be prenatal and perinatal factors (reduced fetal growth and shorter gestation for twins).     

Sex differences in impulsivity: a meta-analysis

Men are overrepresented in socially problematic behaviors, such as aggression and criminal behavior, which have been linked to impulsivity. Our review of impulsivity is organized around the tripartite theoretical distinction between reward hypersensitivity, punishment hyposensitivity, and inadequate effortful control. Drawing on evolutionary, criminological, developmental, and personality theories, we predicted that sex differences would be most pronounced in risky activities with men demonstrating greater sensation seeking, greater reward sensitivity, and lower punishment sensitivity. We predicted a small female advantage in effortful control. We analyzed 741 effect sizes from 277 studies, including psychometric and behavioral measures. Women were consistently more punishment sensitive (d = -0.33), but men did not show greater reward sensitivity (d = 0.01). Men showed significantly higher sensation seeking on questionnaire measures (d = 0.41) and on a behavioral risk-taking task (d = 0.36). Questionnaire measures of deficits in effortful control showed a very modest effect size in the male direction (d = 0.08). Sex differences were not found on delay discounting or executive function tasks. The results indicate a stronger sex difference in motivational rather than effortful or executive forms of behavior control. Specifically, they support evolutionary and biological theories of risk taking predicated on sex differences in punishment sensitivity. A clearer understanding of sex differences in impulsivity depends upon recognizing important distinctions between sensation seeking and impulsivity, between executive and effortful forms of control, and between impulsivity as a deficit and as a trait.     

Business-unit-level relationship between employee satisfaction,employee engagement,and business outcomes: a meta-analysis

Based on 7,939 business units in 36 companies, this study used meta-analysis to examine the relationship at the business-unit level between employee satisfaction-engagement and the business-unit outcomes of customer satisfaction, productivity, profit, employee turnover, and accidents. Generalizable relationships large enough to have substantial practical value were found between unit-level employee satisfaction-engagement and these business-unit outcomes. One implication is that changes in management practices that increase employee satisfaction may increase business-unit outcomes, including profit.     

Age-related differences in deception

Young and older participants judged the veracity of young and older speakers' opinions about topical issues. All participants found it easier to judge when an older adult was lying relative to a young adult, and older adults were worse than young adults at telling when speakers were telling the truth versus lying. Neither young nor older adults were advantaged when judging a speaker from the same age group. Overall, older adults were more transparent as liars and were worse at detecting lies, with older adults' worse emotion recognition fully mediating the relation between age group and lie detection failures.     

Gender differences in mathematics performance: a meta-analysis

Reviewers have consistently concluded that males perform better on mathematics tests than females do. To make a refined assessment of the magnitude of gender differences in mathematics performance, we performed a meta-analysis of 100 studies. They yielded 254 independent effect sizes, representing the testing of 3,175,188 Ss. Averaged over all effect sizes based on samples of the general population, d was -0.05, indicating that females outperformed males by only a negligible amount. For computation, d was -0.14 (the negative value indicating superior performance by females). For understanding of mathematical concepts, d was -0.03; for complex problem solving, d was 0.08. An examination of age trends indicated that girls showed a slight superiority in computation in elementary school and middle school. There were no gender differences in problem solving in elementary or middle school; differences favoring men emerged in high school (d = 0.29) and in college (d = 0.32). Gender differences were smallest and actually favored females in samples of the general population, grew larger with increasingly selective samples, and were largest for highly selected samples and samples of highly precocious persons. The magnitude of the gender difference has declined over the years; for studies published in 1973 or earlier d was 0.31, whereas it was 0.14 for studies published in 1974 or later. We conclude that gender differences in mathematics performance are small. Nonetheless, the lower performance of women in problem solving that is evident in high school requires attention.     

Gender differences in moral orientation: a meta-analysis

C. Gilligan's (1982) critique of L. Kohlberg's theory of moral reasoning and her assertion that two modes of moral reasoning (justice and care) exist have been the subject of debate within the field of psychology for more than 15 years. This meta-analysis was conducted to review quantitatively the work on gender differences in moral orientation. The meta-analysis revealed small differences in the care orientation favoring females (d = -.28) and small differences in the justice orientation favoring males (d = .19). Together, the moderator variables accounted for 16% of the variance in the effect sizes for care reasoning and 17% of the variance in the effect sizes for justice reasoning. These findings do not offer strong support for the claim that the care orientation is used predominantly by women and that the justice orientation is used predominantly by men.     

Sex differences in romantic attachment: a meta-analysis

This article presents the first meta-analysis of sex differences in the avoidance and anxiety dimensions of adult romantic attachment, based on 113 samples (N = 66,132) from 100 studies employing two-dimensional romantic attachment questionnaires (Experiences in Close Relationships, Experiences in Close Relationships-Revised, and Adult Attachment Questionnaire). Overall, males showed higher avoidance and lower anxiety than females, with substantial between-study heterogeneity. Sex differences were much larger in community samples (bivariate D = .28) than in college samples (D = .12); web-based studies showed the smallest sex differences (D = .07) in the opposite direction. Sex differences also varied across geographic regions (overall Ds = .10 to .34). Sex differences in anxiety peaked in young adulthood, whereas those in avoidance increased through the life course. The relevance of these findings for evolutionary models of romantic attachment is discussed, and possible factors leading to underestimation of sex differences are reviewed.     

Gender differences in self-esteem: a meta-analysis.

Two analyses were conducted to examine gender differences in global self-esteem. In analysis I, a computerized literature search yielded 216 effect sizes, representing the testing of 97,121 respondents. The overall effect size was 0.21, a small difference favoring males. A significant quadratic effect of age indicated that the largest effect emerged in late adolescence (d = 0.33). In Analysis II, gender differences were examined using 3 large, nationally representative data sets from the National Center for Education Statistics (NCES). All of the NCES effect sizes, which collectively summarize the responses of approximately 48,000 young Americans, indicated higher male self-esteem (ds ranged from 0.04 to 0.24). Taken together, the 2 analyses provide evidence that males score higher on standard measures of global self-esteem than females, but the difference is small. Potential reasons for the small yet consistent effect size are discussed.     

Sex differences in self-disclosure: a meta-analysis.

A meta-analysis of 205 studies involving 23,702 Ss was conducted to determine whether there are sex differences in self-disclosure. Across these studies, women disclosed slightly more than men (d = .18). This effect size was not homogeneous across studies. Several moderator variables were found. Sex of target and the interaction effect of relationship to target and measure of self-disclosure moderated the effect of sex on self-disclosure. Sex differences in self-disclosure were significantly greater to female and same-sex partners than to opposite-sex or male partners. When the target had a relationship with the discloser (i.e., friend, parent, or spouse), women disclosed more than men regardless of whether self-disclosure was measured by self-report or observation. When the target was a stranger, men reported that they disclosed similarly to women; however, studies using observational measures of self-disclosure found that women disclosed more than men.     

Age-related differences in interlingual priming: a behavioural and electrophysiological investigation

Reaction time (RT) and the N400 ERP component were measured to examine age-related differences in bilingual language processing. Although young bilinguals appear to access both languages simultaneously (i.e., non-selective access), little is known about language selection in older adults. The effect of language context on language selectivity was investigated using interlingual homographs (IH; i.e., words with identical orthography but distinct semantic features in two languages, e.g., coin meaning 'corner' in French and 'money' in English). Younger and older French/English bilinguals were presented with triplets of letter strings comprised of a language context cue, an IH, and a target word, in a lexical decision semantic priming task. RT and ERP results support non-selective language access in young adults; however, the older bilinguals used the language context cue to bias their reading of the IH. Results are discussed in terms of age-related changes in language processing and context use in bilinguals.     

Perceived employability and employee strain: A meta-analysis

This meta-analysis addresses the association between perceived employability (PE) and employee strain (k = 34). Consistent with expectations, PE was negatively related to strain (ρ = −.12, 95% CI = −.16 to −.08). Moderator analysis showed that this relationship was stronger post-2008 (ρ = −.20, 84% CI = −.23 to −.17) versus pre-2008 (ρ = −.06, 84% CI = −.08 to −.05) and in high (ρ = −.17, 84% CI = −.21 to −.14) versus low (ρ = −.07, 84% CI = −.09 to −.06) uncertainty avoidant cultures. Our results suggest that career competency development interventions can be effective for reducing employee strain and that national uncertainty avoidance need be incorporated into models of boundaryless careers, especially as it relates to employee health and well-being.     

Age-related differences in clustering: A new approach

The present study attempted to determine why children under 8 years of age show categorical clustering in free recall above chance expectations, but such organization does not correlate with recall. Six-year-old children and adults were tested for their memory for 24 pictures of categorizable items. Several new measures of organization such as the proportion of items recalled in category strings and number of strings of each length were evaluated. It was found that children's output is characterized by strings of only two intracategory items and many isolates which does not contribute to recall. Adults produced longer strings from more categories which enhanced recall. In addition, different characteristics of output organization predicted recall for adults and children.     

Age-related differences in irrelevant-speech effects

Three experiments examined age-related differences in irrelevant-speech effects. Younger and older adults were required to recall short prose texts or lists of semantically related words presented visually together with distractor speech. In all experiments, older adults made more semantically related intrusion errors from the irrelevant speech than younger adults. Results of a source memory test suggested that these age-related differences in interference are most likely due to both inhibitory deficits and source-monitoring problems. The results lend partial support to the inhibition deficit theory of cognitive aging.     

Age-related differences in the elderly in a spatial recognition task

ABSTRACT

Spatial memory is a cognitive ability which declines with ageing thus showing changes in some process such as the use of allocentric strategies. These age-related changes in spatial orientation suggest that this skill could be an adequate marker of cognitive decline. Many tasks used in investigation to assess spatial memory demand a participant’s active role, which involves that the navigational experience is different for everyone. In this study, the Almeria Spatial Memory Recognition Test (ASMRT), a test based on a recognition paradigm, was used to offer the same experience with the environment. The aim of this research was to determine if the ASMRT is suitable to be applied in the elderly and detect spatial memory differences as one age. The ASMRT and other neuropsychological tests were applied in a sample aged between 50and 79 years. Results revealed a decrease in the ASMRT performance by the older group. No gender differences were found. Performance in attention and visuospatial working memory tests revealed some correlations with the ASMRT performance. In conclusion, this study demonstrates that 70–79-year-old participants clearly show age-related changes in spatial memory. Thanks to its simplicity the ASMRT could be used as a screening test in medical practice.     

Sex differences in left-handedness: a meta-analysis of 144 studies

Human handedness, a marker for language lateralization in the brain, continues to attract great research interest. A widely reported but not universal finding is a greater male tendency toward left-handedness. Here the authors present a meta-analysis of k = 144 studies, totaling N = 1,787,629 participants, the results of which demonstrate that the sex difference is both significant and robust. The overall best estimate for the male to female odds ratio was 1.23 (95% confidence interval = 1.19, 1.27). The widespread observation of this sex difference is consistent with it being related to innate characteristics of sexual differentiation, and its observed magnitude places an important constraint on current theories of handedness. In addition, the size of the sex difference was significantly moderated by the way in which handedness was assessed (by writing hand or by other means), the location of testing, and the year of publication of the study, implicating additional influences on its development.     

Age-related differences in inference revision processing

In comparison to younger adults, older adults demonstrate deficiencies in cognitive and linguistic abilities. Such cognitive factors that decline with age include working memory capacity and inhibitory abilities. The purpose of the present investigation was to measure differences in time course processing of inference revision abilities, as well as working memory, as they exist relative to adult age differences. Fifteen neurologically intact older adults and 15 younger adults participated in this study. A cross-modal lexical priming paradigm was chosen as the measure of the inference revision task; the listening span task of Tompkins, Bloise, Timko, and Baumgaertner (1994) was selected as the measure of working memory. Both groups demonstrated normal priming effects. No age-related differences were found on the working memory measure. Age-related differences did emerge on inferencing abilities. A significant correlation emerged between the older group's performance on comprehending inference revisions and their working memory capacity. Generally, inhibitory abilities and working memory capacity appeared to adversely affect older participant's performance.     

Age-related differences in localized attentional interference

Attentional selection of an object in the visual field degrades processing of neighboring stimuli in young adults. A pair of experiments examined the effects of aging on such localized attentional interference. In Experiment 1, younger and older observers made speeded same-different judgments of target shapes that varied in spatial separation. Performance declined for both age groups as the distance between targets decreased, but an Age x Distance interaction indicated that the magnitude of this effect was larger for older adults. Experiment 2 ruled out sensory masking as an explanation for these findings. Results indicate that older observers experience losses in the ability to attend to multiple spatially proximal stimuli within the visual field.