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.     

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.     

Cognitive functioning in healthy older adults aged 64-81: a cohort study into the effects of age, sex, and education

The objective of this study was to determine a possible differential effect of age, education, and sex on cognitive speed, verbal memory, executive functioning, and verbal fluency in healthy older adults. A group of 578 healthy participants in the age range of 64-81 was recruited from a large population study of healthy adults (Maastricht Aging Study). Even in healthy individuals in this restricted age range, there is a clear, age-related decrease in performance on executive functioning, verbal fluency, verbal memory, and cognitive speed tasks. The capacity to inhibit information is affected most. Education had a substantial effect on cognitive functioning: participants with a middle or high level of education performed better on cognitive tests than did participants with a low level of education. Women performed better than men on verbal memory tasks. Therefore, education and sex must be taken into account when examining an older individual's cognitive performance.     

The Boston Naming Test in Swedish: normative data

The purpose of the present study was to introduce a Swedish version of the Boston Naming Test and to offer normative data based on a sample of native Swedish-speaking healthy adults stratified concerning age, gender, and length of education. The subjects were assessed with other lexical tests and half of the group also performed tests of global cognitive function. A semantic analysis of the responses was performed and the typical Swedish naming of the pictures of BNT was investigated. The results showed that long education, high performance on tests of global cognitive ability (FSIQ), verbal fluency, and other lexical tests had a significant positive association to a good performance on BNT whereas age and gender had a minor influence. The response analysis showed that the more difficult an item was, the more variations in the response pattern. To conclude, the Boston Naming Test is appropriate for use in a Swedish-speaking context and an effective test for assessment of naming ability.     

Gender differences in episodic memory

The relationship between gender and memory has been largely neglected by research, despite occasional studies reporting gender differences in episodic memory performance. The present study examined potential gender differences in episodic memory, semantic memory, primary memory, and priming. Five hundred thirty women and 470 men, randomly sampled from the city of Umeå, Sweden, 35–80 years of age, participated in the study. There were no differences between men and women with regard to age or education, or on a measure of global intellectual functioning. As has been demonstrated previously, men outperformed women on a visuospatial task and women outperformed men on tests of verbal fluency. In addition, the results demonstrated that women consistently performed at a higher level than did men on the episodic memory tasks, although there were no differences between men and women on the tasks assessing semantic memory, primary memory, or priming. The women’s higher level of performance on the episodic memory tasks could not be fully explained by their higher verbal ability.     

Sex differences in cognition are stable over a 10-year period in adulthood and old age

Sex differences in declarative memory and visuospatial ability are robust in cross-sectional studies. The present longitudinal study examined whether sex differences in cognition were present over a 10-year period, and whether age modified the magnitude of sex differences. Tests assessing episodic and semantic memory, and visuospatial ability were administered to 625 nondemented adults (initially aged 35-80 years), participating in the population-based Betula study at two follow-up occasions. There was stability of sex differences across five age groups and over a 10-year period. Women performed at a higher level than men on episodic recall, face and verbal recognition, and semantic fluency, whereas men performed better than women on a task-assessing, visuospatial ability. Sex differences in cognitive functions are stable over a 10-year period and from 35 to 90 years of age.     

Women with Childhood ADHD: Comparisons by Diagnostic Group and Gender

This study compared adult women with childhood ADHD to adult women without childhood ADHD and to adult men with childhood ADHD. The participants, all from a larger longitudinal study, included 30 women and 30 men (approximately age 23 to 24) with childhood ADHD, and 27 women without ADHD. Women with childhood ADHD were matched to comparison women on age, ethnicity, and parental education, and to men with childhood ADHD on age, ethnicity, and IQ. Self- and parent-reports of internalizing, interpersonal, academic, and job impairment, as well as substance use and delinquency indicated group differences on measures of self-esteem, interpersonal and vocational functioning, as well as substance use. Follow-up planned comparison tests revealed that almost all of these differences emerged by diagnostic status, and not by gender. This study adds to research on the negative adult outcomes of ADHD and demonstrates that the outcomes of men and women with childhood ADHD are relatively similar.     

Sex Differences in Cognition are Stable Over a 10-Year Period in Adulthood and Old Age

ABSTRACT

Sex differences in declarative memory and visuospatial ability are robust in cross-sectional studies. The present longitudinal study examined whether sex differences in cognition were present over a 10-year period, and whether age modified the magnitude of sex differences. Tests assessing episodic and semantic memory, and visuospatial ability were administered to 625 nondemented adults (initially aged 35–80 years), participating in the population-based Betula study at two follow-up occasions. There was stability of sex differences across five age groups and over a 10-year period. Women performed at a higher level than men on episodic recall, face and verbal recognition, and semantic fluency, whereas men performed better than women on a task-assessing, visuospatial ability. Sex differences in cognitive functions are stable over a 10-year period and from 35 to 90 years of age.     

Parental interest in children's education,children's self‐esteem and locus of control,and later educational attainment: Twenty‐six year follow‐up of the 1970 British Birth Cohort

Background. Few studies have investigated if mother's interest and father's interest in child's education are linked to educational attainment via their impact on child's self‐esteem and locus of control. Aims. (1) To investigate (after controlling for known confounding factors) the long‐term effect of mother's and father's interest in child's education at age 10 and child's locus of control and self‐esteem at age 10 in educational attainment at age 26; and (2) to explore if mother's interest and father's interest in child's education are linked to child's educational attainment via their effect in increasing child's self‐esteem and internal locus of control. Sample. The study used longitudinal data from sweeps of the 1970 British Cohort Study (BCS70). The initial sample was those 1,737 men and 2,033 women with valid data on age 10 self‐esteem, locus of control, father's interest, mother's interest, and age 26 educational attainment. Of these, 1,326 men and 1,578 women were included in the final analysis. Method. The birth to age 10 factors that were controlled for were birth weight, parental social class, socio‐economic disadvantage, emotional/behavioural problems, cognitive ability, and mother's educational attainment. Results. At the multivariate level, internal locus of control and mother's interest (but not self‐esteem) were significantly related to educational attainment in both men and women. Father's interest was a significant predictor of educational attainment only in women. Parent's interest was not linked to educational attainment via its impact on child's self‐esteem or locus of control. Self‐esteem predicted educational attainment in both genders by increasing internal locus of control, and fathers' interest predicted educational attainment in men by increasing mother's involvement. Conclusion. Although mothers' and fathers' interest in their children's education were not linked to educational attainment via their impact on children's self‐esteem or locus of control, they were significant predictors of educational attainment especially in daughters.     

Sex and post-menopause hormone therapy effects on hippocampal volume and verbal memory

Many studies suggest sex differences in memory and hippocampal size, and that hormone therapy (HT) may positively affect these measures in women; however, the parameters of HT use that most likely confer benefits are debated. We evaluated the impact of sex and postmenopausal HT use on verbal learning and memory and hippocampal size in 94 cognitively intact women and 49 men. Using analysis of covariance that controlled for age and education, women had better total word learning and delayed verbal memory performance than men. HT analyses showed that non-HT users performed similarly to men, while HT users performed better than men in Delayed Memory regardless of whether use was current or in the past. Women had larger hippocampal volumes than men regardless of whether they were HT users. Using univariate linear models, we assessed group differences in the predictive value of hippocampal volumes for verbal learning and memory. Hippocampal size significantly predicted memory performance for men and non-HT users, but not for HT users. This lack of relationship between hippocampal size and verbal learning and memory performance in HT users suggests HT use may impact memory through extra-hippocampal neural systems.     

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.     

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.     

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.     

Swedish norms for word fluency tests: FAS, animals and verbs

Verbal fluency tests are useful measures of acquired language impairment and cognitive decline of various etiologies. The aim of this study was to provide normative data for the Swedish population on the three verbal fluency tests, FAS, Animals and Verbs. A group of 165 healthy participants ranging from 16 to 89 years of age were assessed with the verbal fluency tests and tests of level of intellectual functioning. The sample was stratified by education, age and gender. Level of education had a substantial influence on the performance on verbal fluency, most clearly so in FAS and Verbs. Intellectual level had a positive and significant correlation with all measures of word fluency. Moreover, there was an interaction between age and gender such that women aged between 30 and 64 years outperformed elderly men on FAS and Verbs. Guidelines for instructions and scoring in Swedish are given in the article.     

Fuzzy logic-based observation and evaluation of pedestrians’ behavioral patterns by age and gender

Pedestrian behavior is affected by a multitude of factors such as age, gender, and operating conditions. However, traditional statistical analysis based on observed movements or questionnaire survey is unable to model decision-making process of each pedestrian. This study develops an innovative approach based on fuzzy logic to model the underlying cognitions and behavioral patterns of pedestrians as inferred from field observation in order to evaluate age and gender effect of pedestrians in crossing a signalized crosswalk and when jaywalking. Fuzzy sets and rules are created to model the relationship between human cognitions and decisions of an individual pedestrian. Through calibrating the membership functions of different age and gender groups, behavioral patterns of pedestrians are evaluated and compared. Different from most previous studies, both older and younger pedestrians are found to be less risk-taking than adult pedestrians. Moreover, significant gender difference is found only for cognitions of most hazardous conditions. Consistent with previous studies, it is seen that men have better cognitive skills than women at detecting hazardous situations. The findings from this study are useful to better design safe pedestrian crossing facilities. The fuzzy logic-based approach also provides an innovative way to simulate pedestrian movements in microscopic simulation models.     

Endogenous estradiol is associated with verbal memory in nondemented older men

This study examined the relationship between endogenous hormones and cognitive function in nondemented, ethnically-diverse community-dwelling older men enrolled in the Einstein Aging Study (EAS). All eligible participants (185 men, mean age=81 years) received neuropsychological assessment (Free and Cued Selective Reminding Test (FCSRT), Logical Memory (LM), Trail Making Test B (TMTB), block design (BD)) and provided blood samples for hormonal assays (total estradiol, total testosterone, calculated free testosterone index). Linear regression analysis adjusted for age, education, body mass index, and cardiovascular comorbidities indicated that men with high levels of total estradiol demonstrated better FCSRT verbal memory performance (β=0.17, p<0.02) compared to men with lower levels of total estradiol. The results remained unchanged when the model was further adjusted for ethnicity. We did not detect an association between testosterone and cognitive performance. These findings indicate that high levels of total estradiol in older men are associated with better performance on a cue-based, controlled learning test of verbal memory that is a sensitive predictor of dementia.     

Pathways to adulthood and their precursors and outcomes

Norway has an extensive welfare system which may provide adolescents with many options and high levels of flexibility in terms of pathways to adulthood. This study aimed to describe Norwegian developmental pathways to adulthood, including changes in role statuses (such as living situations, education, work, marriage/cohabitation and parenthood) from 16 to 30 years of age, and their precursors and outcomes. Repeated measures latent class analysis of longitudinal data from 998 Norwegian individuals indicated three main pathways to adulthood among women and men. In both sexes, most individuals undertook a long period of education and postponed family formation. However, some individuals started working early, a group of women established families with partners and children early, and a group of men remained primarily single between 16 and 30 years of age. Furthermore, the results show that pathways to adulthood in Norway are surprisingly similar to pathways in other countries such as the US, UK and Finland. The results indicate that pathways to adulthood are influenced by social reproduction factors in a country with high levels of welfare benefits as well. In addition, the results suggest that pathways involving living with a partner and either higher education or work are associated with high life satisfaction at age 30.     

The effects of marital status on episodic and semantic memory in healthy middle-aged and old individuals

The present study examined the influences of marital status on different episodic and semantic memory tasks. A total of 1882 adult men and women participated in a longitudinal project (Betula) on memory, health and aging. The participants were grouped into two age cohorts, 35-60 and 65-85, and studied over a period of 5 years. Episodic memory tasks concerned recognition and recall, whereas semantic memory tasks concerned knowledge and fluency. The results showed, after controlling for education, some diseases, chronological age and leisure activity as covariates, that there were significant differences between married and single individuals in episodic memory, but not in semantic memory. Married people showed significantly better memory performances than singles in both subsystems of episodic memory, that is, recall and recognition. Also, the rate of decline in episodic memory was significantly larger for singles and widowed than other groups over the 5-year time period in both age groups. The findings demonstrate that the positive relation found between marriage and health can be extended to the relation between marriage and cognitive performance. This effect might be explained by the role played by cognitive stimulation in memory and cognition.     

No protective effects of education during normal cognitive aging: results from the 6-year follow-up of the Maastricht Aging Study

Recent large-scale longitudinal aging studies question earlier claims that higher education protects against cognitive decline in older age. In the present study, the authors addressed this issue by determining whether educational level had an attenuating effect on the rate of cognitive change assessed with a broad range of neuropsychological tests in a community sample of 872 healthy individuals aged 49 to 81 years at baseline. The participants were followed for 6 years and were tested 3 times (at baseline and at 3 and 6 years after baseline). Results of linear mixed-model analyses showed that education had no significant effect on cognitive change over time. These results are discussed in terms of the age range of the sample, definition and range of education, cognitive measures used, length of the study and number of consecutive assessments, and confounding effect of health. The findings question the extent of the presumed protective effects of higher education on cognitive decline during normal aging.