Natural teeth and cognitive function in humans

A number of neurobiological, psychological and social factors may account for cognitive impairment. In animal studies a relation between dental status and cognitive performance has been found. It is unclear whether such a relation exists for humans. In a first step we compared the performance of 1,351 participants (53% women, 47% men; age M = 54.0) with natural teeth to 487 edentulous participants (59% women, 41% men; age M = 71.3) on 12 cognitive tests. The natural teeth group had a lower mean age, fewer women, more years of education, higher mini-mental state (MMSE), and performed significantly higher on several cognitive tests. In a subsequent analysis, the cognitive performance of a subset of the participants (50-85 years) was examined. In this analysis, 211 had natural dentition and 188 were edentulous. The groups were matched for gender, age, social variables, diseases, stress and MMSE. The cognitive disadvantage of the edentulous group was still apparent. The results suggest that functional natural teeth relate to relatively preserved cognitive functioning in older age.     

Mesomorphy correlates with experiential cognitive style

The purpose of this study was to test for a relationship between mesomorphy and experiential cognitive style (S. Epstein, 1994) in a sample of university students (30 women and 24 men). Anthropometric somatotypes were obtained using the Heath-Carter procedure (J. E. L. Carter, 2002). Experiential cognitive style was operationalized as scores on the experiential scale of the Rational Experiential Inventory for Adolescents (A. D. Marks, D. W. Hine, R. L. Blore, & W. J. Phillips, 2008). Nonparametric bootstrap correlations were calculated using 80% confidence intervals. There were significant correlations between mesomorphy and experiential cognitive style for men (r(s) = .33) and women (r(s) = .25). For men, experiential cognitive style was also correlated with endomorphy (r(s) = .39) and ectomorphy (rs = -.48).     

Gender Group Differences in Coping with Chronic Terror: The Israeli Scene

Gender group differences in terror–stress, cognitive appraisals, ways of coping with terror, and stress reactions were explored in a sample of Israeli adults following prolonged exposure to political violence. Data were gathered at the height of the Al-Aqsa Intifada uprising (May/July 2002) from a sample of 707 adult participants (60% women and 40% men) residing in Haifa and northern Israel. Israeli women reported that they were more distressed by political violence than the men did, and they also appraised the crisis situation as more threatening and less manageable. Women reported using more problem-focused as well as emotion-focused coping than men did; both men and women used a mixture of coping strategies. Compared to men, women reported that they experienced more somatic symptoms and more frequent posttraumatic stress symptoms than men did. Negative affectivity was found to mediate gender differences in appraisals, coping, and outcomes. Overall, the nexus of relations among key variables was found to be highly similar for men and women. These data suggest that women may be more reactive to chronic political violence situations than men are. The data are discussed and explicated in the context of stress and coping theory and prior research on political violence and community disasters.     

Gender Effects in Information Processing on a Nonverbal Decoding Task

Women typically outperform men on the ability to assess other people??s nonverbal behavior. This difference might occur because women are taught to be more sensitive to emotional and nonverbal cues at a very early age compared to men. As a consequence, women might use a more favorable cognitive processing style than men during nonverbal decoding. The present study investigated whether this gender difference is due to the use of different cognitive information processing styles (global or local). Participants (N?=?137) were Swiss undergraduate students that were randomly assigned to either a global (focusing on the whole) or a local (focusing on details) priming of information processing style, or to a control group. They then performed a nonverbal decoding task. Results showed that compared to the control group, local priming had beneficial and global priming detrimental effects for nonverbal decoding accuracy. This was due to an improved performance in men after the local priming; women??s performance was not significantly affected by the local priming. Global priming increased nonverbal decoding accuracy in men and decreased performance in women. We conclude that women already use the more beneficial local processing style by default and that men??s performance can be boosted when providing them a processing strategy.     

Cognitive and Personality Characteristics of Masculinity and Femininity Predict Wayfinding Competence and Strategies of Men and Women

Bem (1974) reconceptualized masculinity and femininity as independent and orthogonal constructs that both men and women possess to varying degrees. This perspective was used as a starting point to investigate whether the contributions of gender-typed characteristics can help to account for commonly observed gender differences in wayfinding (the ability to identify one’s current location and successfully navigate to an unseen location in the environment) favoring men. We further divided gender-typed characteristics into cognitive and personality characteristics to assess their separate influence on wayfinding and explored whether gender-typed characteristics predicted self-reported use of masculine wayfinding strategies (i.e., orientation strategies) and self-reported wayfinding competence. Participants were 452 college women and men in a southern U.S. public university. They completed the Gender-Stereotypic Characteristics questionnaire (Diekman and Eagly 2000), a social comparison questionnaire (created by the authors), a wayfinding strategy questionnaire (Lawton 1994), and a wayfinding competence questionnaire (Hegarty et al. 2002). For both men and women, higher masculine cognitive characteristics significantly correlated with greater use of orientation wayfinding strategies typical of men. For men, both higher masculine and feminine cognitive characteristics predicted better overall wayfinding competence whereas for women, only higher masculine cognitive characteristics predicted better overall wayfinding competence. For both men and women, higher feminine personality characteristics predicted poorer wayfinding competence. These results demonstrated the importance of considering cognitive and personality characteristics of masculinity and femininity in explaining individual differences in wayfinding.     

Sex differences in intrinsic aptitude for mathematics and science?: a critical review

This article considers 3 claims that cognitive sex differences account for the differential representation of men and women in high-level careers in mathematics and science: (a) males are more focused on objects from the beginning of life and therefore are predisposed to better learning about mechanical systems; (b) males have a profile of spatial and numerical abilities producing greater aptitude for mathematics; and (c) males are more variable in their cognitive abilities and therefore predominate at the upper reaches of mathematical talent. Research on cognitive development in human infants, preschool children, and students at all levels fails to support these claims. Instead, it provides evidence that mathematical and scientific reasoning develop from a set of biologically based cognitive capacities that males and females share. These capacities lead men and women to develop equal talent for mathematics and science.     

Role of Gender in Dual-Tasking Timed Up and Go Tests: A Cross-Sectional Study

Gender plays a role in cognitive performance. Yet the selection of a secondary task, an important paradigm in studies of posture control, has not considered gender as a variable. We explored whether different cognitive tasks differentially influence performance during the Timed Up and Go (TUG) test in men and women. Twenty young adults performed five cognitive tasks while seated and during the TUG test. Men exhibited a slower normalized cadence than women. When seated, women recalled more items than men and men were more accurate in mental calculation task. There were no changes in spatiotemporal measures. We conclude that gender did not play a major role in motor-cognitive interference during dual task TUG test.     

Gender moderates the impact of need for structure on social beliefs: implications for ethnocentrism and authoritarianism

The present research examines the interplay between individual differences in need for structure, social beliefs, and gender. It is well documented that need for structure, that is, a preference for structure and simplicity in one's thinking, predicts authoritarianism and ethnocentrism. Further, women tend to score lower in authoritarianism and ethnocentrism than men. Although there seem to be no gender differences in need for structure, the present research hypothesizes that the association between need for structure and social beliefs is stronger for men than for women. This hypothesis comes from the observation that, all else being equal, men tend to think more about the domain of beliefs such as authoritarianism and ethnocentrism, which should strengthen the relationship between men's cognitive needs and their social beliefs. The hypothesis is also motivated by the finding that, more than men, women often give priority to caring and compassion when forming beliefs about outgroups. This should weaken the link between women's cognitive needs and their social beliefs. Three studies conducted in the USA (n = 398) and one study conducted in Germany (n = 112) examined whether gender moderated the influence of need for structure on authoritarianism and racism. Using a variety of measures, need for structure predicted authoritarianism and racism for men, but not for women. The discussion focuses on the implications of the present findings for the relationship between cognitive orientations and social beliefs. It is argued that research on cognitive orientation and social beliefs needs to take gender into account to improve its accuracy of prediction.     

Sex differences in theory of mind: A male advantage on Happé's “cartoon” task

It is a commonly held stereotype that women show superior performance on tests of social cognition such as face processing and theory of mind (ToM) compared to men. However, such purported differences have not been empirically tested. In this study 40 healthy men and 40 women matched for age and years of education completed a well-known experimental ToM test requiring the attribution of either physical or mental states (Happé's cartoon task). Men showed superior performance compared to women, with a medium effect size, on both the mental state and physical state cartoons. It is suggested that men may use a cognitive systemising strategy during these tasks. The results emphasise the task-specific nature of sex differences in social cognition and necessitate future work to elucidate individual differences at the interface of cognitive and affective processes.     

BDNF is a novel marker of cognitive function in ageing women: the DR's EXTRA Study

Brain-derived neurotrophic factor (BDNF) is one of the key molecules modulating brain plasticity. While low circulating levels of BDNF have been suggested to predispose to Alzheimer's disease, very little data are available on its association with cognitive function in general population. We evaluated the association between plasma BDNF levels and cognition in a representative population sample of ageing men and women. The subjects (n=1389) were participants of the Dose-Responses to Exercise Training (DR's EXTRA) Study and represent a random sample of Eastern Finnish people (684 men and 705 women), 57-79 years of age at baseline of the study. Plasma BDNF levels were measured by enzyme-linked immunosorbent assay (ELISA). Cognitive function was evaluated using the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) neuropsychological test battery. Women had a higher mean (+/-SEM) plasma BDNF level than men (1721+/-55vs. 1495+/-54pg/ml, P<0.001). In women, 1 SD decrease in BDNF increased the risk for a low score in Naming Test by 53% (95% CI 1.21-1.92, P<0.001), in Mini-Mental State Examination by 63% (95% CI 1.21-2.20, P=0.001), in Word List Memory by 56% (95% CI 1.08-2.26, P=0.019), in Word List Recall by 50% (95% CI 1.10-2.05, P=0.010), in Word List Saving by 49% (95% CI 1.12-1.99, P=0.007), and in Word List Recognition by 64% (95% CI 1.19-2.25, P=0.002). Data were adjusted for age, education, depression, impaired glucose metabolism, cardiovascular disease, antihypertensive medication, lipid lowering medication, use of sex hormones, smoking, alcohol consumption, storing time of plasma in the freezer and platelet count. BDNF was not associated with cognition in men. Present data suggest that plasma BDNF is a biomarker of impaired memory and general cognitive function in ageing women.     

Subjective Distress to Violations of Trust in Mexican American Close Relationships Conforms to Evolutionary Principles

Sex differences in subjective distress to violations of trust in a close relationship were observed among Mexican American men and women. Imagining a partner’s emotional infidelity and other female-linked violations (for example, a partner who no longer desires to work) distressed a larger percentage of women than men. In contrast, imagining a partner’s sexual infidelity and other male-linked violations (for example, a partner who no longer makes an effort to look physically attractive) distressed a larger percentage of men than women. The results from two studies provided compelling evidence against a social–cognitive explanation of the sex differences and for an evolutionary psychology explanation based on men and women responding to threats to their sex-linked mating strategies.     

Sex differences in cognition in healthy elderly individuals

ABSTRACT

Sex differences in patterns of cognitive test performance have been attributed to factors, such as sex hormones or sexual dimorphisms in brain structure, that change with normal aging. The current study examined sex differences in patterns of cognitive test performance in healthy elderly individuals. Cognitive test scores of 957 men and women (age 67–89), matched for overall level of cognitive test performance, age, education, and depression scale score, were compared. Men and women were indistinguishable on tests of auditory divided attention, category fluency, and executive functioning. In contrast, women performed better than men on tests of psychomotor speed and verbal learning and memory, whereas men outperformed women on tests of visuoconstruction and visual perception. Our finding that the pattern of sex differences in cognition observed in young adults is observed in old age has implications for future studies of both healthy elderly individuals and of those with cognitive disorders.     

STEREOTYPE THREAT AND GENDER DIFFERENCES IN PERFORMANCE ON A NOVEL VISUOSPATIAL TASK

Stereotype threat research has shown that being a member of a negatively stereotyped group may result in impaired performance on tests of skills thought to be relevant to the stereotype. This study investigated whether stereotype threat influences gender differences in performance on a novel test of visuospatial ability. Undergraduates ( N  = 194) were told that men outperform women on the test (explicit threat), were given no gender-relevant information (implicit threat), or were told that men and women do not differ (nullified stereotype). Although men outperformed women in the explicit and implicit stereotype threat groups, women's performance did not differ significantly from men's when told there is no gender difference. The effect was most pronounced for difficult line judgments. Although stereotypes regarding visuospatial ability may be less culturally salient than those of other cognitive abilities, these findings suggest that they influence performance nonetheless. Implications for optimizing cognitive test performance are discussed.     

An fMRI study of sex differences in regional activation to a verbal and a spatial task

Sex differences in cognitive performance have been documented, women performing better on some phonological tasks and men on spatial tasks. An earlier fMRI study suggested sex differences in distributed brain activation during phonological processing, with bilateral activation seen in women while men showed primarily left-lateralized activation. This blood oxygen level-dependent fMRI study examined sex differences (14 men, 13 women) in activation for a spatial task (judgment of line orientation) compared to a verbal-reasoning task (analogies) that does not typically show sex differences. Task difficulty was manipulated. Hypothesized ROI-based analysis documented the expected left-lateralized changes for the verbal task in the inferior parietal and planum temporal regions in both men and women, but only men showed right-lateralized increase for the spatial task in these regions. Image-based analysis revealed a distributed network of cortical regions activated by the tasks, which consisted of the lateral frontal, medial frontal, mid-temporal, occipitoparietal, and occipital regions. The activation was more left lateralized for the verbal and more right for the spatial tasks, but men also showed some left activation for the spatial task, which was not seen in women. Increased task difficulty produced more distributed activation for the verbal and more circumscribed activation for the spatial task. The results suggest that failure to activate the appropriate hemisphere in regions directly involved in task performance may explain certain sex differences in performance. They also extend, for a spatial task, the principle that bilateral activation in a distributed cognitive system underlies sex differences in performance.     

Cognitive functioning and neuroticism in an elderly community sample

The relationship between neuroticism and cognitive functioning was investigated using data from a community survey of the elderly. Contrary to Pearson (1993, Personality and Individual Differences, 14, 265–266), neuroticism was related to poorer performance on a number of cognitive measures, but the pattern of correlations differed between men and women. For men there were correlations with a dementia screening test and with tests of episodic memory and fluid intelligence, while for women there were correlations with reaction time measures. It is hypothesized that correlations with neuroticism reflect the effect of chronic stress on cognitive ageing.     

Effects of self-evaluation on the P300 event-related potential

The effects of self evaluation on the P300 event-related potential (ERP) were explored with 56 participants (16 men, 40 women; M age = 23.4 yr., SD = 1.2) across three conditions. The conditions included (1) a standard ERP auditory oddball discrimination between a random target (15% occurrence) and standard stimuli (85% occurrence), (2) the oddball task followed by the additional cognitive task of maintaining a mental count of the target tones, and (3) the oddball task followed by the additional cognitive task of self-evaluating whether they felt surprised by the current occurrence of the target tone. The added cognitive requirements for Conditions 2 and 3 required the subjects to maintain a cognitive readiness for the secondary stimulus-related task during their sensory discrimination response for the standard oddball task. During the self-evaluation condition, the P300 amplitude was significantly larger across all recording locations than the regular oddball condition and the cognitive count condition.     

Digit Symbol Substitution test performance: sex differences in a Hebrew-readers' health population

The Digit Symbol Substitution test is simple to administer and sensitive to individual differences related to cognitive performance. The present study evaluated sex-related differences in performance by a Hebrew reading sample. The test was administered to 275 men and 252 women (age range: 20-44 years). Hebrew women significantly scored higher than the men. Means which increased during four consecutive 30-sec. time periods of performance, was significantly greater for the women than the men. This finding indicates women were more effective on this pair-associated learning task than men.     

Sex differences in cognition among illiterate Bangladeshis: a comparison with literate Bangladeshis and Swedes

We investigated the presence and magnitude of sex differences in late adulthood, assessing 426 illiterate Bangladeshis, 239 literate Bangladeshis, and 598 Swedes. The cognitive domains examined included calculation, episodic memory, spatial visualization, and global cognitive ability. In general, men performed at a higher level than women on tasks assessing calculation and spatial visualization, whereas women performed at a higher level than men on the episodic memory task. Notably, the pattern of cognitive sex differences was similar irrespective of nationality and literacy, although the magnitude of the male advantage was inversely related to level of education. Finally, the low performance of the illiterate women demonstrated the penalizing effect restrictions in public exposure might have on cognitive performance.     

Gender and neural substrates subserving implicit processing of death-related linguistic cues

Our recent functional magnetic resonance imaging study revealed decreased activities in the anterior cingulate cortex (ACC) and bilateral insula for women during the implicit processing of death-related linguistic cues. Current work tested whether aforementioned activities are common for women and men and explored potential gender differences. We scanned twenty males while they performed a color-naming task on death-related, negative-valence, and neutral-valence words. Whole-brain analysis showed increased left frontal activity and decreased activities in the ACC and bilateral insula to death-related versus negative-valence words for both men and women. However, relative to women, men showed greater increased activity in the left middle frontal cortex and decreased activity in the right cerebellum to death-related versus negative-valence words. The results suggest, while implicit processing of death-related words is characterized with weakened sense of oneself for both women and men, men may recruit stronger cognitive regulation of emotion than women.     

Novelty seeking in adulthood: increases accompany decline

Using stereotypes, researchers have predicted that novelty seeking declines in adulthood. Through this cross-sectional study, the authors revealed that only the external sensational type of novelty seeking declined, whereas the internal sensational and internal and external cognitive types remained stable or increased. A population of 233 adults (152 men, 81 women) completed the Novelty Experiencing Scale (P. H. Pearson, 1970). Correlational analyses revealed that older men sought novelty more frequently through cognition than did younger men and that older women were less likely than were younger women to seek novelty through their senses. Multivariate analysis of variance, 2 x 5 (Gender x Age), showed that cognitive novelty seeking increased significantly among participants younger than 50 years of age. Sensational novelty seeking was lower among women older than 40 years and among men older than 50 years. The analyses revealed no significant Gender x Age interactions.