Sex differences in cognition

Sex differences in cognitive skills, grouped into three areas — motor, spatial, and linguistic — are assessed in the context of current notions of cerebral lateralization (Buffery and Gray, 1972). There are few convincing sex differences, either overall, or in interactions with (putative) functional localization. There are several qualifying criteria (nature of further interactions with age, birth order, culture, sex of experimenter, sex role pressure) which would have to be met, but these are as yet inadequately documented. Serious caution is urged on the proliferating number of researchers in this area.     

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.     

Sex differences in face recognition--women's faces make the difference

Sex differences favoring women have been found in face recognition tasks as well as in verbal episodic memory tasks. Women's higher face recognition performance was hypothesized to be related to either their higher verbal ability or to their superiority in recognizing female faces, rather than faces in general. Results showed that whereas there were no differences between men and women in the recognition of male faces, or in verbal ability, women performed at a higher level than men in the recognition of female faces. Verbal ability did not influence women's face recognition performance. Potential explanations for this pattern of data, such as sex differences in interest and prior knowledge, are discussed.     

Sex differences in face recognition and influence of facial affect

To study sex differences in the recognition of human faces with different facial expressions, 65 female and 64 male participants learned to associate names with various male and female neutral faces. During the recall phase, participants were then asked to name the same persons depicting different emotional expressions (neutral, happy, angry, and fearful). Females were faster than males at naming male faces, and males were faster than females at naming female faces. All participants were faster at naming neutral or happy female faces than neural or happy male faces. These results suggest that opposite-sex faces require less processing time than same-sex faces, which is consistent with an evolutionary account.     

Sex differences in spatial cognition, computational fluency, and arithmetical reasoning

Alternative explanations for the male advantage in arithmetical reasoning, as measured by the ability to solve complex word problems, include a male advantage in spatial cognition and a male advantage in computational fluency. The current study was designed to test these competing hypotheses. To this end, 113 male and 123 female undergraduates were administered arithmetical computations and arithmetical reasoning tests, along with an IQ test and a test of spatial cognition. There was no sex difference on the IQ test, but males showed significantly higher mean scores on the arithmetical computations, arithmetical reasoning, and spatial cognition measures. A series of structural equation models indicated that individual differences in arithmetical reasoning were related to individual differences in IQ, spatial abilities, and computational fluency. Moreover, the results suggested that the male advantage in arithmetical reasoning is mediated by the male advantages in both computational fluency and spatial cognition.     

Sex differences in cognition: the role of testosterone and sexual orientation

The performance of both heterosexual and homosexual males and females was compared on four cognitive tasks which have been shown to reveal evidence of sexual dimorphism. In one spatial and one verbal task, significant sex and orientation effects were found. Significant relationships were also found between salivary free-testosterone levels and performance on both spatial tasks, but no significant associations were found for performance on the two verbal tasks. The present study revealed both within- and between-sex differences in cognition and indicates that these differences may be partly accounted for by the activational effects of free testosterone.     

Sex differences in unfamiliar face identification: evidence from matching tasks

Research on sex differences in face recognition has reported mixed results, on balance suggesting an advantage for female observers. However, it is not clear whether this advantage is specific to face processing or reflects a more general superiority effect in episodic memory. The current study therefore examined sex differences with a face-matching task that eliminates memory demands. Across two experiments, female but not male observers showed an own-sex advantage on match trials, in which two pictures have to be identified as the same person. This advantage was present for whole faces and when only the internal or external facial features were shown. Female observers were also more accurate in these three conditions on mismatch encounters, in which two photographs have to be identified as different people, but this reflects a more general effect that is present for male and female faces. These findings converge with claims of a female advantage in face recognition and demonstrate that this effect persists when memory demands are eliminated.     

Neurocognitive mechanisms of individual differences in face cognition: A replication and extension

Face cognition performance is related to individual differences in cognitive subprocesses, as reflected in the amplitudes and latencies of event-related brain potentials (ERPs; Herzmann, Kunina, Sommer, & Wilhelm, 2010). In order to replicate and extend these findings, 110 participants were tested on a comprehensive task battery measuring face cognition abilities and established cognitive abilities, followed by ERP recordings in a face-learning-and-recognition task. We replicated the links of the ERP components indicating the speed of structural face encoding (N170 latency) and access to structural representations in memory (early repetition effect [ERE]/N250r) with the accuracy and speed of face cognition and with established cognitive abilities. As a novel result, we differentiated between the accuracy of face perception and face memory on the behavioral and electrophysiological levels and report a relationship between basic visual processes (P100 amplitude) and face memory. Moreover, the brain–behavior relationships for the ERE/N250r held true, even though we eliminated pictorial and perceptual structural codes from the priming effects by using backward masking of the primes with novel unfamiliar faces. On a methodological level, we demonstrated the utility of the latent difference score modeling technique to parameterize ERP difference components (e.g., ERE/N250r) on a latent level and link them to face cognition abilities.     

Sex differences and the own-gender bias in face recognition: A meta-analytic review

We review the literature on sex differences and the own-gender bias in face recognition. By means of a meta-analysis, we found that girls and women remember more faces than boys and men do (g=0.36), and more female faces (g=0.55), but not more male faces (g=0.08); however, when only male faces are presented, girls and women outperform boys and men (g=0.22). In addition, there is female own-gender bias (g=0.57), but not a male own-gender bias (g= ? 0.03), showing that girls and women remember more female than male faces. It is argued that girls and women have an advantage in face processing and episodic memory, resulting in sex differences for faces, and that the female own-gender bias may stem from an early perceptual expertise for female faces, which may be strengthened by reciprocal interactions and psychological processes directing girls' and women's interest to other females.     

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 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.     

Modeling individual differences in cognition

Many evaluations of cognitive models rely on data that have been averaged or aggregated across all experimental subjects, and so fail to consider the possibility of important individual differences between subjects. Other evaluations are done at the single-subject level, and so fail to benefit from the reduction of noise that data averaging or aggregation potentially provides. To overcome these weaknesses, we have developed a general approach to modeling individual differences using families of cognitive models in which different groups of subjects are identified as having different psychological behavior. Separate models with separate parameterizations are applied to each group of subjects, and Bayesian model selection is used to determine the appropriate number of groups. We evaluate this individual differences approach in a simulation study and show that it is superior in terms of the key modeling goals of prediction and understanding. We also provide two practical demonstrations of the approach, one using the ALCOVE model of category learning with data from four previously analyzed category learning experiments, the other using multidimensional scaling representational models with previously analyzed similarity data for colors. In both demonstrations, meaningful individual differences are found and the psychological models are able to account for this variation through interpretable differences in parameterization. The results highlight the potential of extending cognitive models to consider individual differences.     

Sex differences in pain

Are there sex differences in pain? For experimentally delivered somatic stimuli, females have lower thresholds, greater ability to discriminate, higher pain ratings, and less tolerance of noxious stimuli than males. These differences, however, are small, exist only for certain forms of stimulation and are affected by many situational variables such as presence of disease, experimental setting, and even nutritive status. For endogenous pains, women report more multiple pains in more body regions than men. With no obvious underlying rationale, some painful diseases are more prevalent among females, others among males and, for many diseases, symptoms differ between females and males. Sex differences in attitudes exist that affect not only reporting, coping, and responses to treatment, but also measurement and treatment. So many variables are operative, however, that the most striking feature of sex differences in reported pain experience is the apparent overall lack of them. On the other hand, deduction from known biological sex differences suggests that these are powerful sex differences in the operation of pain mechanisms. First, the vaginal canal provides an additional route in women for internal trauma and invasion by pathological agents that puts them at greater risk for developing hyperalgesia in multiple body regions. Second, sex differences in temporal patterns are likely to give rise to sex differences in how pain is "learned" and stimuli are interpreted, a situation that could lead to a greater variability and wider range of pains without obvious peripheral pathology among females. Third, sex differences in the actions of sex hormones suggest pain-relevant differences in the operation of many neuroactive agents, opiate and nonopiate systems, nerve growth factor, and the sympathetic system. Thus, while inductive analysis of existing data demonstrate more similarities than differences in pain experience between females and males, deductive analysis suggests important operational sex differences in its production.     

Sex differences in self-silencing

The construct of self-silencing was proposed to account for women's greater vulnerability to developing depression. This study of 1,117 students (795 women and 322 men) explored possible explanations for the empirical finding that men self-silence to the same or greater extent than women. Analysis showed that men reported more self-silencing than women. A factor analysis confirmed the subscale structure of the Silencing the Self Scale for women and men, with relatively few departures from the originally proposed subscales. Depression and self-silencing scores were correlated positively for both men and women. The results of two multiple regressions, performed separately for men and women, showed that depressive symptomatology accounted for a significant percentage of the variance in self-silencing but that social desirability did not account for a significant increment in the variance accounted for in silencing the self. The scores on the Care as Self-sacrifice and the Divided Self subscales were intercorrelated for women, but not for men, indicating that there may be a sex difference in perception of self-silencing behavior.     

Sex differences in depression

The role of housewife has been hypothesized as the source of excess mental illness among married women as compared with married men. The present study found both housewives and working wives significantly more depressed than working husbands. Although working wives report that they do more housework than husbands, this factor was not significantly related to depression for either wives or husbands. It is suggested that the risk factors for depression, including marriage for women, may be better understood in the context of clinical theories of depression, especially the learned helplessness model.     

Gender differences in animal cognition science

Animal Cognition - Women’s representation in science is increasing steadily, with some fields closing gender parity in terms of participation and scientific output. Animal cognition appears...     

Sex differences in preadolescent self-disclosure

Both amount and content of self-disclosure may vary with sex role. Both adult and preadolescent females have been reported as engaging in greater amounts of self-disclosure than males; the present study attempted to replicate these findings with preadolescents, and to investigate sex differences in the content of self-disclosure. A self-disclosure questionnaire covering a wide range of subjects was administered to 307 urban children. The sex difference on the total number of items revealed to a friend closely approached significance, with girls showing greater disclosure. When only intimate content items were examined, the sex difference reached clear significance. Content analysis showed that girls were more willing to reveal items related to emotionality, anxiety, and dependence.     

Sex differences in achievement motivation

Abstract.— Norwegian undergraduate psychology students were given Heckhausen's TAT test of achievement motivation prior to or after final course examination. Women obtained higher mean score on Fear of Failure than men on both occasions. There was no sex difference in length of protocol, nor was this variable related to any of the motivation scores. Success in terms of examination results did not affect motivation scores, whereas failure led to higher score on Hope of Success for men but not for women.