Sex differences in children's discrepant perceptions of peer acceptance

Sex differences in children's play patterns during middle childhood are thought to promote greater awareness of social acceptance among girls compared with boys. The present study posited that girls are more discerning of peer acceptance than are boys; however, these sex differences were predicted to vary depending on how discrepant perceptions were assessed (i.e., inaccuracy versus bias). Additional differences were expected if children perceived acceptance by same- versus opposite-sex peers. Participants were 912 third through fifth graders (420 girls and 492 boys). Consistent with predictions, boys were more inaccurate than girls, but only for perceived acceptance by same-sex peers. As expected, girls were more negatively biased than boys, but only for perceived acceptance by opposite-sex peers. Results did not support the hypothesis that boys have more positively biased perceptions of peer acceptance than girls. Overall, these findings raise important issues regarding the evaluation of children's discrepant self-perceptions of peer acceptance.     

Tacting and manding in correspondence training: effects of child selection of verbalization.

We investigated correspondence between verbal and nonverbal behavior in preschool children in a play setting. Four children (4 years old) participated in a multiple baseline across subjects design. Children were asked what toy(s) they were going to play with during an immediately upcoming play period. When no contingencies were placed on either verbal or nonverbal behavior, children showed high rates of correspondence. When children were required to verbalize about a toy from a restricted range of infrequently used toys, but no contingencies were placed on correspondence, low rates of correspondence were observed. High rates of correspondence were noted when reinforcement was contingent on it. Results are discussed in terms of tacting and manding.     

Sex differences in historical knowledge and school grades: a 26 nation study

Sex differences among ninth grade school students in historical knowledge and grades were examined in 29 samples drawn from 26 countries. Boys obtained higher mean scores on the tests of historical knowledge in all samples, while girls obtained better grades in 22 of the samples.     

Sex differences in general knowledge in German high school students

This study examines the hypotheses that (1) 17 domains of general knowledge can be identified; (2) these are positively intercorrelated and form a general factor of general knowledge; (3) there are sex differences in the different domains of general knowledge; and (4) males have more general knowledge in more of these domains than females and in the general factor. The study tests these hypotheses on a sample of 302 German high school students. All the hypotheses were confirmed. All the domains of general knowledge were positively intercorrelated. A general factor was found that explained 31.3% of the variance. Males achieved significantly and substantially higher scores than females in general knowledge of 0.60d. The only area in which females scored significantly higher than males was Nutrition for which there was a medium size effect size (d=0.50). The results are highly similar to those among university students in Northern Ireland reported by Lynn, Irwing, and Cammock (2002).     

Sex differences in dichotic listening

The present study quantified the magnitude of sex differences in perceptual asymmetries as measured with dichotic listening. This was achieved by means of a meta-analysis of the literature dating back from the initial use of dichotic listening as a measure of laterality. The meta-analysis included 249 effect sizes pertaining to sex differences and 246 effect sizes for the main effect of laterality. The results showed small and homogeneous sex differences in laterality in favor of men (d=0.054). The main effect of laterality was of medium magnitude (d=0.609) but it was heterogeneous. Homogeneity for the main effect of laterality was achieved through partitioning as a function of task, demonstrating larger asymmetries for verbal (d=0.65) than for non-verbal tasks (d=0.45). The results are discussed with reference to top-down and bottom-up factors in dichotic listening. The possible influence of a publication bias is also discussed.     

Sex differences in expressive drawing

We examined sex differences in expressive drawings produced by 105 boys and 105 girls aged 9-15 years. The drawings were classified according to the type of expressive strategy used to depict emotion (literal, content, abstract, or any combination of these), and rated according to the complexity of that strategy. A creative/divergent thinking task (figural form) was used to assess the relationship between expressive drawing and figural creativity. As predicted, girls scored higher than boys on the expressive drawing task. Specifically, girls relied less often on literal strategies alone and were more likely to combine literal expression with metaphorical (content and abstract) expression than boys. There was a linear relationship between expressive drawing and divergent thinking scores. These results are consistent with the idea that boys and girls differ in the expressive component of emotion, and suggest that these sex differences extend to the expressive drawing domain. They also suggest that divergent thinking may be involved in the ability to draw expressively.     

Sex differences in the relation between math performance, spatial skills, and attitudes

Sex differences have been previously found in cognitive and affective predictors of math achievement, including spatial skills and math attitudes. It is important to determine whether there are sex differences not only in the predictors themselves, but also in the nature of their relation to math achievement. The present paper examined spatial skills and math attitudes as predictors of curriculum-based measures of math performance in middle-school students, specifically comparing the patterns of these predictive relations for boys and girls. The results of the current study showed that, despite similar levels of math performance for boys and girls, the significance of particular predictors varied as a function of sex. Specifically, spatial skills predicted math performance in boys, but not in girls. We suggest that sex differences in spatial reasoning in conjunction with the differential involvement of spatial reasoning in math problem solving may lead to later sex differences in math outcomes.     

Single landmark learning in rats: Sex differences in a navigation task

In Experiments 1 and 2, rats were trained in a Morris pool to find a hidden platform located some distance away from a single landmark. Males learned to swim to the platform faster than females, but on test trials without the platform, males, unlike females, spent less time in the platform quadrant of the pool in the second half of each test trial than in the first. They also showed greater persistence in searching in the platform quadrant over a series of extinction trials. In Experiments 3a and 3b, the problem was made easier by locating the platform closer to the solitary landmark. Now males and females learned to swim to the platform equally rapidly, and both stopped searching in the platform quadrant in the second half of each test trial. Experiment 4 ruled out the possibility that males´ shorter latencies to find the platform in Experiment 2 were due to their swimming faster than females.     

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 the links between attractiveness, self-esteem and the body

Two studies were conducted to determine: if the links between the body and self-perceived attractiveness and self-esteem for men and women differ. Following evolutionary and social learning theories, affective and cognitive links were hypothesized for women's attractiveness while no links were hypothesized for men's attractiveness. Additionally, affective links were expected for women's self-esteem while no links were expected for men's self-esteem. The results obtained supported these hypotheses. Findings are discussed in terms of the societal value placed on women's attractiveness and evolutionary theory.     

Sex differences in brain activity related to general and emotional intelligence

The study investigated gender differences in resting EEG (in three individually determined narrow alpha frequency bands) related to the level of general and emotional intelligence. Brain activity of males decreased with the level of general intelligence, whereas an opposite pattern of brain activity was observed in females. This difference was most pronounced in the upper-alpha band which is related to semantic memory processes. It was further found that highly intelligent males displayed greater decoupling of frontal brain areas, whereas highly intelligent females showed more coupling between frontal and parietal/occipital brain areas. Similar, but less significant differences were observed for the two area scores of strategic and experiential emotional intelligence. It appears that males and females have different resting EEG correlates of IQ.     

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 jealousy in response to infidelity: Evaluation of demographic moderators in a national random sample

Studies examining sex differences in jealousy have often relied on student samples and were restricted to the evaluation of a selected few moderators. In this study, a nationally representative survey of American households was presented with either an actual or a hypothetical infidelity scenario (which appeared as either a forced choice or as continuous measures). Significant sex differences only emerged for forced choice measures and not for continuous measures. Importantly, this effect appeared most strongly in participants reporting reactions to an actual infidelity. We also explored a number of potential moderators of this effect. These moderators were more influential for the hypothetical than for the actual infidelity scenario. Exploratory analysis of additional demographic variables was conducted.     

Sex differences in the effects of visual contact and eye contact in negotiations

Previous research has proposed that the ability to see others would benefit negotiations. We argue that this view is too narrow and that the impact of visual contact on negotiated agreements depends on the meaning individuals ascribe to either its presence or absence. Based on previous research showing that females are more likely to understand others in the presence of visual contact while males understand others better in the absence of visual contact, we explore how visual contact, eye contact, and sex affect the quality of negotiated agreements in a meta-analysis (Study 1) and a laboratory experiment (Study 2). The two studies combined show that because direct communication via the face facilitates a shared understanding for two unacquainted females, their agreements are of higher quality when they have visual contact compared to when they do not (Study 1), and if they have visual contact, their agreements are better when they have eye contact than when they do not (Study 2). Because communication via the face increases discomfort between two unacquainted males, their agreements are of higher quality when they do not have visual contact (Study 1), and if they do have visual contact, their agreements are better when they have no eye contact than when they do (Study 2).     

Sex differences in the ability to recognise non-verbal displays of emotion: A meta-analysis

The present study aimed to quantify the magnitude of sex differences in humans' ability to accurately recognise non-verbal emotional displays. Studies of relevance were those that required explicit labelling of discrete emotions presented in the visual and/or auditory modality. A final set of 551 effect sizes from 215 samples was included in a multilevel meta-analysis. The results showed a small overall advantage in favour of females on emotion recognition tasks (d = 0.19). However, the magnitude of that sex difference was moderated by several factors, namely specific emotion, emotion type (negative, positive), sex of the actor, sensory modality (visual, audio, audio-visual) and age of the participants. Method of presentation (computer, slides, print, etc.), type of measurement (response time, accuracy) and year of publication did not significantly contribute to variance in effect sizes. These findings are discussed in the context of social and biological explanations of sex differences in emotion recognition.     

Sex differences in object location memory and spatial navigation in Long-Evans rats

In both humans and rodents, males typically excel on a number of tasks requiring spatial ability. However, human females exhibit advantages in memory for the spatial location of objects. This study investigated whether rats would exhibit similar sex differences on a task of object location memory (OLM) and on the watermaze (WM). We predicted that females should outperform males on the OLM task and that males should outperform females on the WM. To control for possible effects of housing environment, rats were housed in either complex environments or in standard shoebox housing. Eighty Long-Evans rats (40 males and 40 females) were housed in either complex (Complex rats) or standard shoebox housing (Control rats). Results indicated that males had superior performance on the WM, whereas females outperformed males on the OLM task, regardless of housing environment. As these sex differences cannot be easily attributed to differences in cognitive style related to linguistic processing of environmental features or to selection pressures related to the hunting gathering evolutionary prehistory of humans, these data suggest that sex differences in spatial ability may be related to traits selected for by polygynous mating strategies.     

Sex drive, attachment style, relationship status and previous infidelity as predictors of sex differences in romantic jealousy

Recent research examining sex differences in jealousy suggests that more men than women tend to be distressed by sexual infidelity, and that more women than men tend to be distressed by emotional infidelity. The primary explanation for these findings is that evolution has shaped men’s and women’s responses to enhance their chances of reproductive success. However, within-sex differences are also found in terms of relative level of distress at sexual or emotional infidelity. This study examined the effect of alternative variables, particularly those associated with attachment and sexual motivations, on both between- and within-sex differences in relative distress at sexual and emotional infidelity. A community sample of 437 adults provided data using a self-report questionnaire. The results showed that sex drive was a significant predictor of distress at jealousy for both men and women, while attachment avoidance and previously being the victim of a sexual infidelity were significant predictors for men only, and relationship status was a significant predictor for women only. Overall, these findings support the evolutionary model of jealousy, and suggest that sex-specific evolved psychological mechanisms underpinning jealousy are influenced by attachment and sexual motivations.     

Sex differences in the processing of flankers

The study of sex differences in cognition has often focused on differences in spatial processing. Recently, sex differences in selective attention have been observed by Bayliss, di Pellegrino, and Tipper (2005), showing that women are more influenced than men by irrelevant spatial cues. The current study elaborates on this finding and tests whether sex differences in the processing of irrelevant information also occur in a simpler task, in which there is no need to redirect visual attention and no need to remember multiple spatial stimulus–response associations. Here, attention is studied using a novel combination of a go/no-go task and a flanker task. A total of 80 neurotypical participants were studied, and it was found that responses in women were more strongly affected by flanker information than were responses in men. This suggests that these sex differences were not due to difficulties with spatial reorientation, or remembering spatial stimulus–response relationships. The findings are discussed in the context of the hunter–gatherer theory of sex differences.     

Sex differences in humor production ability: A meta-analysis

We offer the first systematic quantitative meta-analysis on sex differences in humor production ability. We included studies where participants created humor output that was assessed for funniness by independent raters. Our meta-analysis includes 36 effect sizes from 28 studies published between 1976 and 2018 (N = 5057, 67% women). Twenty of the 36 effect sizes, accounting for 61% of the participants, were not previously published. Results based on random-effects model revealed that men's humor output was rated as funnier than women's, with a combined effect size d = 0.321. Results were robust across various moderators and study characteristics, and multiple tests indicated that publication bias is unlikely. Both evolutionary and cultural explanations were considered and discussed.