This review brings together evidence from a diverse field of methods for investigating sex differences in language processing. Differences are found in certain language-related deficits, such as stuttering, dyslexia, autism and schizophrenia. Common to these is that language problems may follow...... studies on regional grey matter distribution using voxel-based morphometry, indicate no consistent differences between males and females in language related cortical regions. Language function in Wada-tests, aphasia, and in normal aging also fails to show sex differentiation. ...
This review brings together evidence from a diverse field of methods for investigating sex differences in language processing. Differences are found in certain language-related deficits, such as stuttering, dyslexia, autism and schizophrenia. Common to these is that language problems may follow...
Becker, Jill B
Women exhibit more rapid escalation from casual drug taking to addiction, exhibit a greater withdrawal response with abstinence, and tend to exhibit greater vulnerability than men in terms of treatment outcome. In rodents, short-term estradiol intake in female rats enhances acquisition and escalation of drug taking, motivation for drugs of abuse, and relapse-like behaviors. There is also a sex difference in the dopamine response in the nucleus accumbens. Ovariectomized female rats exhibit a smaller initial dopamine increase after cocaine treatment than castrated males. Estradiol treatment of ovariectomized female rats enhances stimulated dopamine release in the dorsolateral striatum, but not in the nucleus accumbens, resulting in a sex difference in the balance between these two dopaminergic projections. In the situation where drug-taking behavior becomes habitual, dopamine release has been reported to be enhanced in the dorsolateral striatum and attenuated in the nucleus accumbens. The sex difference in the balance between these neural systems is proposed to underlie sex differences in addiction.
Geerdink, Danny; Buter, Jeffrey; van Beek, Teris A.; Minnaard, Adriaan J.
Virgin females of the parasitoid wasp Trichogramma turkestanica produce minute amounts of a sex pheromone, the identity of which has not been fully established. The enantioselective synthesis of a putative component of this pheromone, (6S,8S,10S)-4,6,8,10-tetramethyltrideca-2E,4E-dien-1-ol (2), is
Scully, Eileen P
This review will outline the multilevel effects of biological sex on HIV acquisition, pathogenesis, treatment response, and prospects for cure. Potential mechanisms will be discussed along with future research directions. HIV acquisition risk is modified by sex hormones and the vaginal microbiome, with the latter acting through both inflammation and local metabolism of pre-exposure prophylaxis drugs. Female sex associates with enhanced risk for non-AIDS morbidities including cardiovascular and cerebrovascular disease, suggesting different inflammatory profiles in men and women. Data from research on HIV cure points to sex differences in viral reservoir dynamics and a direct role for sex hormones in latency maintenance. Biological sex remains an important variable in determining the risk of HIV infection and subsequent viral pathogenesis, and emerging data suggest sex differences relevant to curative interventions. Recruitment of women in HIV clinical research is a pathway to both optimize care for women and to identify novel therapeutics for use in both men and women.
Becker, Jill B; Hu, Ming
Sex differences are present for all of the phases of drug abuse (initiation, escalation of use, addiction, and relapse following abstinence). While there are some differences among specific classes of abused drugs, the general pattern of sex differences is the same for all drugs of abuse. Females begin regularly self-administering licit and illicit drugs of abuse at lower doses than do males, use escalates more rapidly to addiction, and females are at greater risk for relapse following abstinence. In this review, sex differences in drug abuse are discussed for humans and in animal models. The possible neuroendocrine mechanisms mediating these sex differences are discussed.
Sex differences in the brain are real and clinically important but often grossly distorted in popular discourse. Considering the public's deep fascination with sex difference research and its impact on issues from mental health to education and workplace equity, neuroscientists should pay greater heed to its misappropriation and to studying how gender enculturation shapes neural function. Copyright © 2011 Elsevier Inc. All rights reserved.
Men have higher blood pressure than women through much of life regardless of race and ethnicity. This is a robust and highly conserved sex difference that it is also observed across species including dogs, rats, mice and chickens and it is found in induced, genetic and transgenic animal models of hypertension. Not only do the differences between the ovarian and testicular hormonal milieu contribute to this sexual dimorphism in blood pressure, the sex chromosomes also play a role in and of themselves. This review primarily focuses on epidemiological studies of blood pressure in men and women and experimental models of hypertension in both sexes. Gaps in current knowledge regarding what underlie male-female differences in blood pressure control are discussed. Elucidating the mechanisms underlying sex differences in hypertension may lead to the development of anti-hypertensives tailored to one's sex and ultimately to improved therapeutic strategies for treating this disease and preventing its devastating consequences. PMID:22417477
Jennifer L Anderson
Full Text Available Within vertebrates, major sex determining genes can differ among taxa and even within species. In zebrafish (Danio rerio, neither heteromorphic sex chromosomes nor single sex determination genes of large effect, like Sry in mammals, have yet been identified. Furthermore, environmental factors can influence zebrafish sex determination. Although progress has been made in understanding zebrafish gonad differentiation (e.g. the influence of germ cells on gonad fate, the primary genetic basis of zebrafish sex determination remains poorly understood. To identify genetic loci associated with sex, we analyzed F(2 offspring of reciprocal crosses between Oregon *AB and Nadia (NA wild-type zebrafish stocks. Genome-wide linkage analysis, using more than 5,000 sequence-based polymorphic restriction site associated (RAD-tag markers and population genomic analysis of more than 30,000 single nucleotide polymorphisms in our *ABxNA crosses revealed a sex-associated locus on the end of the long arm of chr-4 for both cross families, and an additional locus in the middle of chr-3 in one cross family. Additional sequencing showed that two SNPs in dmrt1 previously suggested to be functional candidates for sex determination in a cross of ABxIndia wild-type zebrafish, are not associated with sex in our AB fish. Our data show that sex determination in zebrafish is polygenic and that different genes may influence sex determination in different strains or that different genes become more important under different environmental conditions. The association of the end of chr-4 with sex is remarkable because, unique in the karyotype, this chromosome arm shares features with known sex chromosomes: it is highly heterochromatic, repetitive, late replicating, and has reduced recombination. Our results reveal that chr-4 has functional and structural properties expected of a sex chromosome.
Tolor, Alexander; Brannigan, Gary G.
This rebuttal of the criticisms made by Evans and Sperekas points to the fact that sex differences have been found by the authors on locus of control scales, that the purported sex-biased items in the Future Events Test are not necessarily outside the response repetoire of women, and the criticism of including female relevant items cannot be…
Becker, Jill B.; Hu, Ming
Sex differences are present for all of the phases of drug abuse (initiation, escalation of use, addiction, and relapse following abstinence). While there are some differences among specific classes of abused drugs, the general pattern of sex differences is the same for all drugs of abuse. Females begin regularly self-administering licit and illicit drugs of abuse at lower doses than do males, use escalates more rapidly to addiction, and females are at greater risk for relapse following abstin...
Becker, Jill B; McClellan, Michele L; Reed, Beth Glover
This review discusses alcohol and other forms of drug addiction as both a sociocultural and biological phenomenon. Sex differences and gender are not solely determined by biology, nor are they entirely sociocultural. The interactions among biological, environmental, sociocultural, and developmental influences result in phenotypes that may be more masculine or more feminine. These gender-related sex differences in the brain can influence the responses to drugs of abuse, progressive changes in the brain after exposure to drugs of abuse and whether addiction results from drug-taking experiences. In addition, the basic laboratory evidence for sex differences is discussed within the context of four types of sex/gender differences. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Becker, Jill B.; McClellan, Michele L.; Reed, Beth Glover
This review discusses alcohol/other drug addiction as both a sociocultural and biological phenomenon. Sex differences and gender are not solely determined by biology, nor are they entirely sociocultural. The interactions among biological, environmental, sociocultural and developmental influences result in phenotypes that may be more masculine or more feminine. These gender-related sex differences in the brain can influence the responses to drugs of abuse, progressive changes in the brain afte...
Plevkova, J; Buday, T; Kavalcikova-Bogdanova, N; Ioan, I; Demoulin-Alexikova, S
Majority of patients visiting cough clinics are postmenopausal women, who are affected by intractable cough for years. Why the cough reflex becomes exaggerated in women is not known. Basic research excludes females from the studies contributing to the sex bias which may be responsible for lack of understanding of "hypersensitive" cough in women. Biological and behavioural differences between women and men are the factors affecting cough physiology. Gender also shapes the patterns of behaviour and determines the character of environmental exposures which differs between sexes. The article offers an insight into the physiology of the cough, differences in the maturation of it and biological, social and behavioural factors contributing to the sex differences in cough. Copyright © 2016 Elsevier B.V. All rights reserved.
In the majority of neuropsychiatric conditions, marked gender-based differences have been found in the epidemiology, clinical manifestations, and therapy of disease. Emerging data suggest that gender differences exist also in the epidemiology, and pathophysiology of epilepsy. The present review summarizes the current information regarding gender and epilepsy. These differences are regarded from the perspective of innate sex differences in cerebral morphology, structural and functional connections, and assuming that these differences may render men and women differently vulnerable to epileptogenicity. Copyright © 2014 Elsevier Inc. All rights reserved.
Fattore, Liana; Melis, Miriam; Fadda, Paola; Fratta, Walter
Gender-dependent differences in the rate of initiation and frequency of misuse of addicting drugs have been widely described. Yet, men and women also differ in their propensity to become addicted to other rewarding stimuli (e.g., sex, food) or activities (e.g., gambling, exercising). The goal of the present review is to summarize current evidence for gender differences not only in drug addiction, but also in other forms of addictive behaviours. Thus, we first reviewed studies showing gender-dependent differences in drug addiction, food addiction, compulsive sexual activity, pathological gambling, Internet addiction and physical exercise addiction. Potential risk factors and underlying brain mechanisms are also examined, with particular emphasis given to the role of sex hormones in modulating addictive behaviours. Investigations on factors allowing the pursuit of non-drug rewards to become pathological in men and women are crucial for designing gender-appropriate treatments of both substance and non-substance addictions. Copyright © 2014 Elsevier Inc. All rights reserved.
In this special issue, the topic of sex difference in the field of anesthesiology is featured. Eight subtopics are discussed including 1) sex differences in cardiovascular medicine, 2) perioperative cardiovascular management, 3) sex differences in the respiratory functions of the upper airway, 4) sex differences in the anesthetic management, 5) sex differences in pain, 6) sex differences in laboratory medicine, 7) sex differences in pharmacokinetics of anesthetics, and 8) postoperative nausea and vomiting. Although recent clinical and experimental studies have shown the existence of sex and/or gender differences in many fields of medicine, our knowledge of sex differences in anesthesiology is apparently insufficient. I believe that anesthesiologists should pay more attention to this topic to improve our daily practice of anesthesia.
Dickens, B M; Serour, G I; Cook, R J; Qiu, R-Z
This paper contrasts ethical approaches to sex selection in countries where discrimination against women is pervasive, resulting in selection against girl children, and in countries where there is less general discrimination and couples do not prefer children of either sex. National sex ratio imbalances where discrimination against women is common have resulted in laws and policies, such as in India and China, to deter and prevent sex selection. Birth ratios of children can be affected by techniques of prenatal sex determination and abortion, preconception sex selection and discarding disfavored embryos, and prefertilization sperm sorting, when disfavored sperm remain unused. Incentives for son preference are reviewed, and laws and policies to prevent sex selection are explained. The elimination of social, economic and other discrimination against women is urged to redress sex selection against girl children. Where there is no general selection against girl children, sex selection can be allowed to assist families that want children of both sexes.
Full Text Available Purpose. Female runners typically suffer more from chronic running injuries than age-matched males, although the exact biome-chanical mechanisms behind the increased susceptibility of female runners are unknown. This study aimed to compare sex differences in tibiocalcaneal kinematics during the stance phase of running. Methods. Twenty male and twenty female participants ran at 4.0 m · s–1. Tibiocalcaneal kinematics were measured using an eight-camera motion analysis system and compared using independent samples t tests. Results. Peak eversion and tibial internal rotation angles were shown to be significantly greater in female runners. Conclusions. based on these observations, it was determined that female runners may be at increased risk from chronic injury development in relation to excessive tibiocalcaneal motions in the coronal and transverse planes.
Naninck, E.F.G.; Lucassen, P.J.; Bakker, J.
Depression is one of the most common, costly and severe psychopathologies worldwide. Its incidence, however, differs significantly between the sexes, and depression rates in women are twice those of men. Interestingly, this sex difference emerges during adolescence. Although the adolescent period is
Shors, Tracey J; Millon, Emma M; Chang, Han Yan M; Olson, Ryan L; Alderman, Brandon L
It is generally accepted that women tend to ruminate more than men do and these thought patterns are often associated with depressive symptoms (Nolen-Hoeksema et al., ). Based on these findings, we considered whether the relationship between rumination and depression is stronger in women than in men and if so, whether this might explain the higher prevalence of major depressive disorder (MDD) in women and finally, whether the association can be disrupted through a mind/body intervention. Adult men and women, most of whom were clinically depressed, participated in an intervention known as MAP Training, which combines "mental" training with silent meditation and "physical" training with aerobic exercise (Shors et al., ). After eight weeks of training, both men and women reported significantly fewer symptoms of depression and fewer ruminative thoughts (Alderman et al., ). Statistical correlations between depressive symptoms and ruminative thoughts were strong and significant (rho > 0.50; p depressive symptoms relate to "reflective" ruminations, which involve analyses of past events, feelings, and behaviors. This is also the only relationship that dissipated after the intervention. In general, these analyses suggest that the strength of the relationship between depressive symptoms and rumination does not necessarily explain sex differences in depression; but because the relationship is strong, targeting rumination through intervention can reduce the incidence of MDD, which is more prevalent among women. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Lindekleiv, Haakon M; Valen-Sendstad, Kristian; Morgan, Michael K
. The female preponderance is usually explained by systemic factors (hormonal influences and intrinsic wall weakness); however, the uneven sex distribution of intracranial aneurysms suggests a possible physiologic factor-a local sex difference in the intracranial arteries....
Kolář, František; Ošťádal, Bohuslav
Roč. 207, č. 4 (2013), s. 584-587 ISSN 1748-1708 Institutional support: RVO:67985823 Keywords : heart * vascular * risk factors * sex Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery Impact factor: 4.251, year: 2013
Schousboe, Karoline; Willemsen, Gonneke; Kyvik, Kirsten O
pairs (including opposite sex pairs) aged 20-29 and 30-39 from eight different twin registries participating in the GenomEUtwin project. Quantitative genetic analyses were conducted and sex differences were explored. Variation in BMI was greater for women than for men, and in both sexes was primarily...... explained by additive genetic variance in all countries. Sex differences in the variance components were consistently significant. Results from analyses of opposite sex pairs also showed evidence of sex-specific genetic effects suggesting there may be some differences between men and women in the genetic...... factors that influence variation in BMI. These results encourage the continued search for genes of importance to the body composition and the development of obesity. Furthermore, they suggest that strategies to identify predisposing genes may benefit from taking into account potential sex specific effects....
Sex, the states of being female or male, potentially interacts with all xenobiotic exposures, both inadvertent and deliberate, and influences their toxicokinetics (TK), toxicodynamics, and outcomes. Sex differences occur in behavior, exposure, anatomy, physiology, biochemistry, and genetics, accounting for female-male differences in responses to environmental chemicals, diet, and pharmaceuticals, including adverse drug reactions (ADRs). Often viewed as an annoying confounder, researchers have studied only one sex, adjusted for sex, or ignored it. Occupational epidemiology, the basis for understanding many toxic effects in humans, usually excluded women. Likewise, Food and Drug Administration rules excluded women of childbearing age from drug studies for many years. Aside from sex-specific organs, sex differences and sex × age interactions occur for a wide range of disease states as well as hormone-influenced conditions and drug distribution. Women have more ADRs than men; the classic sex hormone paradigm (gonadectomy and replacement) reveals significant interaction of sex and TK including absorption, distribution, metabolisms, and elimination. Studies should be designed to detect sex differences, describe the mechanisms, and interpret these in a broad social, clinical, and evolutionary context with phenomena that do not differ. Sex matters, but how much of a difference is needed to matter remains challenging.
In recent decades, premarital sex, extramarital sex, and homosexuality have become increasingly visible in China, leading scholars to claim that a national "sex revolution" is under way. However, China's internal sociocultural diversity calls this nation-level generalization into question. How do sex ideologies vary across China's distinct provinces? To what extent are interprovince variations in sex ideologies associated with distinct macrolevel social factors in China? In this research, data from the 2010 China General Social Survey and the 2011 Chinese Statistics Yearbook were analyzed using multilevel models to test four contending theories of interprovince differences in sex ideologies in China: modernization, Westernization, deindustrialization, and the "rice theory." The modernization theory was unsupported by the results, as socioeconomic development is not significantly associated with sex ideologies. Higher levels of deindustrialization and Westernization were associated with less traditional sex ideologies, but the strength of association varied across the domains of premarital sex, extramarital sex, and homosexuality. The rice theory was consistently supported, as the distinction between rice and wheat agriculture explained up to 30% of the province-level variance in sex ideologies. The findings underline the roles of both long-standing geographic differences and recent social changes in shaping China's ideational landscape of sex.
Bale, Tracy L; Epperson, C Neill
Sex differences in stress responses can be found at all stages of life and are related to both the organizational and activational effects of gonadal hormones and to genes on the sex chromosomes. As stress dysregulation is the most common feature across neuropsychiatric diseases, sex differences in how these pathways develop and mature may predict sex-specific periods of vulnerability to disruption and increased disease risk or resilience across the lifespan. The aging brain is also at risk to the effects of stress, where the rapid decline of gonadal hormones in women combined with cellular aging processes promote sex biases in stress dysregulation. In this Review, we discuss potential underlying mechanisms driving sex differences in stress responses and their relevance to disease. Although stress is involved in a much broader range of diseases than neuropsychiatric ones, we highlight here this area and its examples across the lifespan. PMID:26404716
Bale, Tracy L; Epperson, C Neill
Sex differences in stress responses can be found at all stages of life and are related to both the organizational and activational effects of gonadal hormones and to genes on the sex chromosomes. As stress dysregulation is the most common feature across neuropsychiatric diseases, sex differences in how these pathways develop and mature may predict sex-specific periods of vulnerability to disruption and increased disease risk or resilience across the lifespan. The aging brain is also at risk to the effects of stress, where the rapid decline of gonadal hormones in women combined with cellular aging processes promote sex biases in stress dysregulation. In this Review, we discuss potential underlying mechanisms driving sex differences in stress responses and their relevance to disease. Although stress is involved in a much broader range of diseases than neuropsychiatric ones, we highlight here this area and its examples across the lifespan.
Lenroot, Rhoshel K.; Giedd, Jay N.
Adolescence is a time of increased divergence between males and females in physical characteristics, behavior, and risk for psychopathology. Here we will review data regarding sex differences in brain structure and function during this period of the lifespan. The most consistent sex difference in brain morphometry is the 9-12% larger brain size…
Jordan M Ramsey
Full Text Available Sex is an important factor in the prevalence, incidence, progression, and response to treatment of many medical conditions, including autoimmune and cardiovascular diseases and psychiatric conditions. Identification of molecular differences between typical males and females can provide a valuable basis for exploring conditions differentially affected by sex.Using multiplexed immunoassays, we analyzed 174 serum molecules in 9 independent cohorts of typical individuals, comprising 196 males and 196 females. Sex differences in analyte levels were quantified using a meta-analysis approach and put into biological context using k-means to generate clusters of analytes with distinct biological functions. Natural sex differences were established in these analyte groups and these were applied to illustrate sexually dimorphic analyte expression in a cohort of 22 males and 22 females with Asperger syndrome. Reproducible sex differences were found in the levels of 77 analytes in serum of typical controls, and these comprised clusters of molecules enriched with distinct biological functions. Analytes involved in fatty acid oxidation/hormone regulation, immune cell growth and activation, and cell death were found at higher levels in females, and analytes involved in immune cell chemotaxis and other indistinct functions were higher in males. Comparison of these naturally occurring sex differences against a cohort of people with Asperger syndrome indicated that a cluster of analytes that had functions related to fatty acid oxidation/hormone regulation was associated with sex and the occurrence of this condition.Sex-specific molecular differences were detected in serum of typical controls and these were reproducible across independent cohorts. This study extends current knowledge of sex differences in biological functions involved in metabolism and immune function. Deviations from typical sex differences were found in a cluster of molecules in Asperger syndrome
Fejer, René; Hartvigsen, Jan; Kyvik, Kirsten Ohm
Experimental studies have suggested biological factors as a possible explanation for gender disparities in perception of pain. Recently, heritability of liability to neck pain (NP) has been found to be statistically significantly larger in women compared to men. However, no studies have been...... conducted to determine whether the sex differences in heritability of NP are due to sex-specific genetic factors. Data on lifetime prevalence of NP from a population-based cross-sectional survey of 33,794 Danish twins were collected and age-stratified univariate biometrical modeling using sex......-limitation models was performed based on 10,605 dizygotic (DZ) twins of opposite sex to estimate the qualitative sex differences. In a full sex-limitation model the genetic component in females were higher than in males, but the genetic and the shared environmental correlations were equal to what is normally...
Full Text Available Sex differences in the brain appear to play an important role in the prevalence and progression of various neuropsychiatric disorders, but to date little is known about the cerebral mechanisms underlying these differences. One widely reported finding is that women demonstrate higher cerebral perfusion than men, but the underlying cause of this difference in perfusion is not known. This study investigated the putative role of steroid hormones such as oestradiol, testosterone, and dehydroepiandrosterone sulphate (DHEAS as underlying factors influencing cerebral perfusion. We acquired arterial spin labelling perfusion images of 36 healthy adult subjects (16 men, 20 women. Analyses on average whole brain perfusion levels included a multiple regression analysis to test for the relative impact of each hormone on the global perfusion. Additionally, voxel-based analyses were performed to investigate the sex difference in regional perfusion as well as the correlations between local perfusion and serum oestradiol, testosterone, and DHEAS concentrations. Our results replicated the known sex difference in perfusion, with women showing significantly higher global and regional perfusion. For the global perfusion, DHEAS was the only significant predictor amongst the steroid hormones, showing a strong negative correlation with cerebral perfusion. The voxel-based analyses revealed modest sex-dependent correlations between local perfusion and testosterone, in addition to a strong modulatory effect of DHEAS in cortical, subcortical, and cerebellar regions. We conclude that DHEAS in particular may play an important role as an underlying factor driving the difference in cerebral perfusion between men and women.
Studied three different criteria of within-sex, gender-related individual differences taken from three studies. Data showed that items displaying large sex differences tended also to correlate most strongly with independent gender-related criteria within the sexes. Discusses assessment implications for gender-related and other group-related…
E.M. Rodenburg (Eline)
textabstractIn the early sixties, a prominent professor in Clinical Pharmacology at the University College in London, D.R. Laurence, stated: “There are no clinically important sex differences in drug action, except, of course, to sex steroid hormones, but the subject is poorly documented. Women
Canino, Glorisa J.; And Others
Examined sex differences in rates of depressive disorders and depressive symptomatology, as measured by the Diagnostic Interview Schedule, for an island-wide probability sample of Puerto Rico. Found depression significantly more prevalent among women than men. Discusses risk factors from a sex-role and cultural perspective. (Author/KS)
Tybur, J.M.; Bryan, A.D.; Lieberman, D.L.; Caldwell Hooper, A.E.; Merriman, L.A.
Across two studies, we test for sex differences in the factor structure, factor loadings, concurrent validity, and means of the Three Domain Disgust Scale. In Study 1, we find that the Three Domain Disgust Scale has indistinguishable factor structure and factor loadings for men and women. In Study
Steven C Munger
Full Text Available In vertebrates, primary sex determination refers to the decision within a bipotential organ precursor to differentiate as a testis or ovary. Bifurcation of organ fate begins between embryonic day (E 11.0-E12.0 in mice and likely involves a dynamic transcription network that is poorly understood. To elucidate the first steps of sexual fate specification, we profiled the XX and XY gonad transcriptomes at fine granularity during this period and resolved cascades of gene activation and repression. C57BL/6J (B6 XY gonads showed a consistent ~5-hour delay in the activation of most male pathway genes and repression of female pathway genes relative to 129S1/SvImJ, which likely explains the sensitivity of the B6 strain to male-to-female sex reversal. Using this fine time course data, we predicted novel regulatory genes underlying expression QTLs (eQTLs mapped in a previous study. To test predictions, we developed an in vitro gonad primary cell assay and optimized a lentivirus-based shRNA delivery method to silence candidate genes and quantify effects on putative targets. We provide strong evidence that Lmo4 (Lim-domain only 4 is a novel regulator of sex determination upstream of SF1 (Nr5a1, Sox9, Fgf9, and Col9a3. This approach can be readily applied to identify regulatory interactions in other systems.
Michael J. Tagler; Heather M. Jeffers
Sex differences in reactions to partner infidelity have often been studied by comparing emotional reactions to scenarios of sexual versus emotional infidelity. Men, relative to women, tend to react with more distress to partner sexual infidelity than to emotional infidelity. Evolutionary theorists interpret this difference as evidence of sexually dimorphic selection pressures. In contrast, focusing only on the simple effects within each sex, social-cognitive theorists suggest that men and wom...
Warner, Timothy A; Libman, Matthew K; Wooten, Katherine L; Drugan, Robert C
Various animal models of depression have been used to seek a greater understanding of stress-related disorders. However, there is still a great need for novel research in this area, as many individuals suffering from depression are resistant to current treatment methods. Women have a higher rate of depression, highlighting the need to investigate mechanisms of sex differences. Therefore, we employed a new animal model to assess symptoms of depression, known as intermittent swim stress (ISS). In this model, the animal experiences 100 trials of cold water swim stress. ISS has already been shown to cause signs of behavioral depression in males, but has yet to be assessed in females. Following ISS exposure, we looked at sex differences in the Morris water maze and forced swim test. The results indicated a spatial learning effect only in the hidden platform task between male and female controls, and stressed and control males. A consistent spatial memory effect was only seen for males exposed to ISS. In the forced swim test, both sexes exposed to ISS exhibited greater immobility, and the same males and females also showed attenuated climbing and swimming, respectively. The sex differences could be due to different neural substrates for males and females. The goal of this study was to provide the first behavioral examination of sex differences following ISS exposure, so the stage of estrous cycle was not assessed for the females. This is a necessary future direction for subsequent experiments. The current article highlights the importance of sex differences in response to stress.
Lesley J. Rogers
Full Text Available A recent upsurge in unitary biological explanations for gender differences in behavior (i.e. that they are “hard-wired” in the genetic code, put forward not only in books written for a general audience but also in scientific papers, makes it important to examine the fallacies of these ideas. Such genetic and hormonal explanations of human behavior, formulated with little consideration of the influences of experience, and often without taking experience into account at all, are part of a new wave of genetic explanations for a broad range of human behavior, as explained in the paper. These ideas are far from new; moreover, they are pseudoscientific and are used for political influence under the guise of science. They are a conservative social force that maintains social and educational inequalities between women and men. This paper explains that causal explanations of differences between the sexes are of two completely different types: unitary (genetic determinist versus interactive explanations. The false reasoning used to support genetic determinist explanations of sex differences in behavior is discussed. To illustrate what biology really tells us about gender differentiation, the paper discusses the interactive roles of genetic, hormonal and environmental influences on the development of gender differences. These interactions are illustrated using two model biological systems (e.g. the intertwined influences of genes, sex hormones and experience on the development of sex differences in behavior in rats, and sex differences in neuronal connections in chickens. There is plenty of scientific evidence to show the complex interactive, and ever changing, influences of experience and genes that take place as an organism develops and throughout its life. Malleability of brain and behavior can be shown clearly using animal models, and the processes involved apply also to the development of brain and behavior in humans. We diminish our understanding
Elise E. DeVito
Full Text Available Data presented are from a sex-differences secondary analysis of a human laboratory investigation of single doses of atomoxetine (40 mg and 80 mg versus placebo in abstinent individuals with cocaine use disorders (CUD. Subjective drug effects, cognitive performance and cardiovascular measures were assessed. The primary atomoxetine dose analyses (which do not consider sex as a factor are reported in full elsewhere (DeVito et al., 2017 .
Lindekleiv, Haakon M; Valen-Sendstad, Kristian; Morgan, Michael K
Subarachnoid hemorrhage (SAH) is a serious condition, occurring more frequently in females than in males. SAH is mainly caused by rupture of an intracranial aneurysm, which is formed by localized dilation of the intracranial arterial vessel wall, usually at the apex of the arterial bifurcation. T....... The female preponderance is usually explained by systemic factors (hormonal influences and intrinsic wall weakness); however, the uneven sex distribution of intracranial aneurysms suggests a possible physiologic factor-a local sex difference in the intracranial arteries....
Full Text Available Although the first sex-dependent differences for chemosensory processing were reported in the scientific literature over 60 years ago, the underlying mechanisms are still unknown. Generally, more pronounced sex-dependent differences are noted with increased task difficulty or with increased levels of intranasal irritation produced by the stimulus. Whether differences between the sexes arise from differences in chemosensory sensitivity of the two intranasal sensory systems involved or from differences in cognitive processing associated with emotional evaluation of the stimulants is still not known. We used simultaneous and complementary measures of electrophysiological (EEG, psychophysiological, and psychological responses to stimuli varying in intranasal irritation and oldorousness to investigate whether sex differences in the processing of intranasal irritation are mediated by varying sensitivity of the involved sensory systems or by differences in cognitive and/or emotional evaluation of the irritants. Women perceived all stimulants more irritating and they exhibited larger amplitudes of the late positive deflection of the event-related potential than men. No significant differences in sensory sensitivity, anxiety and arousal responses could be detected. Our findings suggest that men and women process intranasal irritation differently. Importantly, the differences cannot be explained by variation in sensory sensitivity to irritants, differences in anxiety or differences in physiological arousal. We propose that women allocate attention stronger to potentially noxious stimuli, which eventually causes differences in cognitive appraisal and subjective perception.
Krauss, I; Grau, S; Mauch, M; Maiwald, C; Horstmann, T
The purpose of the study was to investigate sex-related differences in foot morphology. In total, 847 subjects were scanned using a 3-D-footscanner. Three different analysis methods were used: (1) comparisons were made for absolute foot measures within 250-270 mm foot length (FL); (2) and for averaged measures (% FL) across all sizes; (3) the feet were then classified using a cluster analysis. Within 250-270 mm FL, male feet were wider and higher (mean differences (MD) 1.3-5.9 mm). No relevant sex-related differences could be found in the comparison of averaged measures (MD 0.3-0.6% FL). Foot types were categorised into voluminous, flat-pointed and slender. Shorter feet were more often voluminous, longer feet were more likely to be narrow and flat. However, the definition of 'short' and 'long' was sex-related; thus, allometry of foot measures was different. For shoe design, measures should be derived for each size and sex separately. Different foot types should be considered to account for the variety in foot shape. Improper footwear can cause foot pain and deformity. Therefore, knowledge of sex-related differences in foot measures is important to assist proper shoe fit in both men and women. The present study supplements the field of knowledge within this context with recommendations for the manufacturing of shoes.
Serrano, A K; Rojas, J C; Cruz-López, L C; Malo, Edi A; Mikery, O F; Castillo, A
Lutzomyia cruciata (Coquillet) is a vector of cutaneous leishmaniasis in Mexico and Central America. However, several aspects of its ecology and behavior are unknown, including whether a male pheromone partially mediates the sexual behavior of this sand fly. In this study, we evaluated the behavioral response of females to male abdominal extracts in a Y-tube olfactometer. The volatile compounds from male abdominal extracts were identified by gas chromatography-mass spectrometry and compared with those of female abdominal extracts. Finally, the disseminating structures of the putative sex pheromone were examined by scanning electron microscopy in the male abdomen. Females were more attracted to male abdominal extract than to the hexane control, suggesting the presence of male-produced sex pheromone. The male abdominal extracts were characterized by the presence of 12 sesquiterpene compounds. The major component, an unknown sesquiterpene with an abundance of 60%, had a mass spectrum with molecular ion of m/z 262. In contrast, the abdominal female extracts contained saturated fatty acids. Finally, we detected the presence of small "papules" with a mammiform morphology distributed on the abdominal surface of tergites IV-VII of male Lu. cruciata These structures are not present in females. We conclude that Lu. cruciata males likely produce a pheromone involved in attracting or courting females. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: firstname.lastname@example.org.
Miller, David I; Halpern, Diane F
Surprising new findings indicate that many conclusions about sex differences and similarities in cognitive abilities need to be reexamined. Cognitive sex differences are changing, decreasing for some tasks whereas remaining stable or increasing for other tasks. Some sex differences are detected in infancy, but the data are complex and depend on task characteristics. Diverse disciplines have revolutionized our understanding of why these differences exist. For instance, fraternal-twin studies align with earlier literature to help establish the role of prenatal androgens and large international datasets help explain how cultural factors such as economic prosperity and gender equity affect females and males differently. Understanding how biological and environmental factors interact could help maximize cognitive potential and address pressing societal issues. Copyright © 2013 Elsevier Ltd. All rights reserved.
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.
Lubienski, Sarah Theule; Miller, Emily K.; Saclarides, Evthokia Stephanie
Women in the sciences who earn PhDs are less likely than their male counterparts to pursue tenure-track positions at research universities. Moreover, among those who become STEM researchers, men have been found to publish more than women. These patterns raise questions about when sex differences in publication begin. Using data from a survey of…
Wijnhoven, H. A H; de Vet, Henrica C W; Picavet, H. Susan J
STUDY DESIGN. Cross-sectional population-based study. OBJECTIVE. To study sex differences in consequences of musculoskeletal pain (MP): limited functioning, work leave or disability, and healthcare use. SUMMARY OF BACKGROUND DATA. MP is a major public health problem in developed countries due to
van der Sluis, S.; Vinkhuyzen, A.A.E.; Boomsma, D.I.; Posthuma, D.
Achievement motivation is considered a prerequisite for success in academic as well as non-academic settings. We studied sex differences in academic and general achievement motivation in an adult sample of 338 men and 497 women (ages 18-70 years). Multi-group covariance and means structure analysis
Grgurevic, Neza; Majdic, Gregor
Although considerable progress has been made in our understanding of brain function, many questions remain unanswered. The ultimate goal of studying the brain is to understand the connection between brain structure and function and behavioural outcomes. Since sex differences in brain morphology were first observed, subsequent studies suggest different functional organization of the male and female brains in humans. Sex and gender have been identified as being a significant factor in understanding human physiology, health and disease, and the biological differences between the sexes is not limited to the gonads and secondary sexual characteristics, but also affects the structure and, more crucially, the function of the brain and other organs. Significant variability in brain structures between individuals, in addition to between the sexes, is factor that complicates the study of sex differences in the brain. In this review, we explore the current understanding of sex differences in the brain, mostly focusing on preclinical animal studies. © 2016 The Author(s). published by Portland Press Limited on behalf of the Biochemical Society.
Lau, Charles Q.
This study contributes to the emerging demographic literature on same-sex couples by comparing the level and correlates of union stability among 4 types of couples: (a) male same-sex cohabitation, (b) female same-sex cohabitation, (c) different-sex cohabitation, and (d) different-sex marriage. The author analyzed data from 2 British birth cohort…
Hypothalamic-pituitary-gonadal (HPG) axis function fundamentally affects the physiology of eating. We review sex differences in the physiological and pathophysiological controls of amounts eaten in rats, mice, monkeys, and humans. These controls result from interactions among genetic effects, organizational effects of reproductive hormones (i.e., permanent early developmental effects), and activational effects of these hormones (i.e., effects dependent on hormone levels). Male-female sex differences in the physiology of eating involve both organizational and activational effects of androgens and estrogens. An activational effect of estrogens decreases eating 1) during the periovulatory period of the ovarian cycle in rats, mice, monkeys, and women and 2) tonically between puberty and reproductive senescence or ovariectomy in rats and monkeys, sometimes in mice, and possibly in women. Estrogens acting on estrogen receptor-α (ERα) in the caudal medial nucleus of the solitary tract appear to mediate these effects in rats. Androgens, prolactin, and other reproductive hormones also affect eating in rats. Sex differences in eating are mediated by alterations in orosensory capacity and hedonics, gastric mechanoreception, ghrelin, CCK, glucagon-like peptide-1 (GLP-1), glucagon, insulin, amylin, apolipoprotein A-IV, fatty-acid oxidation, and leptin. The control of eating by central neurochemical signaling via serotonin, MSH, neuropeptide Y, Agouti-related peptide (AgRP), melanin-concentrating hormone, and dopamine is modulated by HPG function. Finally, sex differences in the physiology of eating may contribute to human obesity, anorexia nervosa, and binge eating. The variety and physiological importance of what has been learned so far warrant intensifying basic, translational, and clinical research on sex differences in eating. PMID:23904103
Full Text Available Sex differences in the development of hypertension and cardiovascular disease have been described in humans and in animal models. In this paper we will review some of our studies which have as their emphasis the examination of the role of sex differences and sex steroids in modulating the central actions of angiotensin II (ANG II via interactions with free radicals and nitric oxide, generating pathways within brain circumventricular organs and in central sympathomodulatory systems. Our studies indicate that low-dose infusions of ANG II result in hypertension in wild-type male mice but not in intact wild-type females. Furthermore, we have demonstrated that ANG II-induced hypertension in males is blocked by central infusions of the androgen receptor antagonist, flutamide, and by central infusions of the superoxide dismutase mimetic, tempol. We have also found that, in comparison to females, males show greater levels of intracellular reactive oxygen species in circumventricular organ neurons following long-term ANG II infusions. In female mice, ovariectomy, central blockade of estrogen receptors or total knockout of estrogen a receptors augments the pressor effects of ANG II. Finally, in females but not in males, central blockade of nitric oxide synthase increases the pressor effects of ANG II. Taken together, these results suggest that sex differences and estrogen and testosterone play important roles in the development of ANG II-induced hypertension.
Tipton, Ashlee J; Sullivan, Jennifer C
Hypertension is a major risk factor for cardiovascular disease, stroke, and end-organ damage. There is a sex difference in blood pressure (BP) that begins in adolescence and continues into adulthood, in which men have a higher prevalence of hypertension compared with women until the sixth decade of life. Less than 50% of hypertensive adults in the United States manage to control their BP to recommended levels using current therapeutic options, and women are more likely than are men to have uncontrolled high BP. This, is despite the facts that more women compared with men are aware that they have hypertension and that women are more likely to seek treatment for the disease. Novel therapeutic targets need to be identified in both sexes to increase the percentage of hypertensive individuals with controlled BP. The purpose of this article was to review the available literature on the role of T cells in BP control in both sexes, and the potential therapeutic application/implications of targeting immune cells in hypertension. A search of PubMed was conducted to determine the impact of sex on T cell-mediated control of BP. The search terms included sex, gender, estrogen, testosterone, inflammation, T cells, T regulatory cells, Th17 cells, hypertension, and blood pressure. Additional data were included from our laboratory examinations of cytokine expression in the kidneys of male and female spontaneously hypertensive rats (SHRs) and differential gene expression in both the renal cortex and mesenteric arterial bed of male and female SHRs. There is a growing scientific literature base regarding the role of T cells in the pathogenesis of hypertension and BP control; however, the majority of these studies have been performed exclusively in males, despite the fact that both men and women develop hypertension. There is increasing evidence that although T cells also mediate BP in females, there are distinct differences in both the T-cell profile and the functional impact of sex
Faber, James E; Moore, Scott M; Lucitti, Jennifer L; Aghajanian, Amir; Zhang, Hua
Premenopausal women and intact female rodents sustain smaller cerebral infarctions than males. Several sex-dependent differences have been identified as potential contributors, but many questions remain unanswered. Mice exhibit wide variation in native collateral number and diameter (collateral extent) that is dependent on differences in genetic background, aging, and other comorbidities and that contributes to their also-wide differences in infarct volume. Likewise, variation in infarct volume correlates with differences in collateral-dependent blood flow in patients with acute ischemic stroke. We examined whether extent of pial collateral arterioles and posterior communicating collateral arteries (PComAs) differ depending on sex in young, aged, obese, hypertensive, and genetically different mice. We combined new data with meta-analysis of our previously published data. Females of C57BL/6J (B6) and BALB/cByJ (BC) strains sustained smaller infarctions than males after permanent MCA occlusion. This protection was unchanged in BC mice after introgression of the B6 allele of Dce1, the major genetic determinant of variation in pial collaterals among mouse strains. Consistent with this, collateral extent in these and other strains did not differ with sex. Extent of PComAs and primary cerebral arteries also did not vary with sex. No dimorphism was evident for loss of pial collateral number and/or diameter (collateral rarefaction) caused by aging, obesity, and hypertension, nor for collateral remodeling after pMCAO. However, rarefaction was greater in females with long-standing hypertension. We conclude that smaller infarct volume in female mice is not due to greater collateral extent, greater remodeling, or less rarefaction caused by aging, obesity, or hypertension.
Michael J. Tagler
Full Text Available Sex differences in reactions to partner infidelity have often been studied by comparing emotional reactions to scenarios of sexual versus emotional infidelity. Men, relative to women, tend to react with more distress to partner sexual infidelity than to emotional infidelity. Evolutionary theorists interpret this difference as evidence of sexually dimorphic selection pressures. In contrast, focusing only on the simple effects within each sex, social-cognitive theorists suggest that men and women do not differ in their reactions to partner infidelity. As evidenced by recent rival meta-analytic reports, these diverging perspectives remain largely unresolved and contentious. The present study was designed to take a new approach by measuring attitudes toward partner infidelity. Results were consistent with the evolutionary perspective: Men, to a significantly larger degree than women, evaluated partner sexual infidelity more negatively than emotional infidelity.
Tagler, Michael J; Jeffers, Heather M
Sex differences in reactions to partner infidelity have often been studied by comparing emotional reactions to scenarios of sexual versus emotional infidelity. Men, relative to women, tend to react with more distress to partner sexual infidelity than to emotional infidelity. Evolutionary theorists interpret this difference as evidence of sexually dimorphic selection pressures. In contrast, focusing only on the simple effects within each sex, social-cognitive theorists suggest that men and women do not differ in their reactions to partner infidelity. As evidenced by recent rival meta-analytic reports, these diverging perspectives remain largely unresolved and contentious. The present study was designed to take a new approach by measuring attitudes toward partner infidelity. Results were consistent with the evolutionary perspective: Men, to a significantly larger degree than women, evaluated partner sexual infidelity more negatively than emotional infidelity.
Boone, Alexander P; Gong, Xinyi; Hegarty, Mary
Research on human navigation has indicated that males and females differ in self-reported navigation strategy as well as objective measures of navigation efficiency. In two experiments, we investigated sex differences in navigation strategy and efficiency using an objective measure of strategy, the dual-solution paradigm (DSP; Marchette, Bakker, & Shelton, 2011). Although navigation by shortcuts and learned routes were the primary strategies used in both experiments, as in previous research on the DSP, individuals also utilized route reversals and sometimes found the goal location as a result of wandering. Importantly, sex differences were found in measures of both route selection and navigation efficiency. In particular, males were more likely to take shortcuts and reached their goal location faster than females, while females were more likely to follow learned routes and wander. Self-report measures of strategy were only weakly correlated with objective measures of strategy, casting doubt on their usefulness. This research indicates that the sex difference in navigation efficiency is large, and only partially related to an individual's navigation strategy as measured by the dual-solution paradigm.
Examines fantasies about the opposite sex expressed by 116 children, adolescents, and adults responding to the Drawing from Imagination task of the Silver Drawing Test of Cognition and Emotion. Results indicate that both males and females expressed more negative than positive feelings toward subjects of the opposite sex. Males were more negative.…
John J. McMahon
Full Text Available The countermovement jump (CMJ is commonly used to explore sex differences in neuromuscular function, but previous studies have only reported gross CMJ measures or have partly examined CMJ phase characteristics. The purpose of this study was to explore differences in CMJ phase characteristics between male and female athletes by comparing the force-, power-, velocity-, and displacement-time curves throughout the entire CMJ, in addition to gross measures. Fourteen men and fourteen women performed three CMJs on a force platform from which a range of kinetic and kinematic variables were calculated via forward dynamics. Jump height (JH, reactive strength index modified, relative peak concentric power, and eccentric and concentric displacement, velocity, and relative impulse were all greater for men (g = 0.58–1.79. Relative force-time curves were similar between sexes, but relative power-, velocity-, and displacement-time curves were greater for men at 90%–95% (immediately before and after peak power, 47%–54% (start of eccentric phase and 85%–100% (latter half of concentric phase, and 65%–87% (bottom of countermovement and initial concentric phase of normalized jump time, respectively. The CMJ distinguished between sexes, with men demonstrating greater JH through applying a larger concentric impulse and, thus, achieving greater velocity throughout most of the concentric phase, including take-off.
Full Text Available The fungal kingdom displays a fascinating diversity of sex-determination systems. Recent advances in genomics provide insights into the molecular mechanisms of sex, mating type determination, and evolution of sexual reproduction in many fungal species in both ancient and modern phylogenetic lineages. All major fungal groups have evolved sexual differentiation and recombination pathways. However, sexuality is unknown in arbuscular mycorrhizal fungi (AMF of the phylum Glomeromycota, an ecologically vital group of obligate plant root symbionts. AMF are commonly considered an ancient asexual lineage dating back to the Ordovician, approximately 460 M years ago. In this study, we used genomic and transcriptomic surveys of several AMF species to demonstrate the presence of conserved putative sex pheromone-sensing mitogen-activated protein (MAP kinases, comparable to those described in Ascomycota and Basidiomycota. We also find genes for high mobility group (HMG transcription factors, homologous to SexM and SexP genes in the Mucorales. The SexM genes show a remarkable sequence diversity among multiple copies in the genome, while only a single SexP sequence was detected in some isolates of Rhizophagus irregularis. In the Mucorales and Microsporidia, the sexM gene is flanked by genes for a triosephosphate transporter (TPT and a RNA helicase, but we find no evidence for synteny in the vicinity of the Sex locus in AMF. Nonetheless, our results, together with previous observations on meiotic machinery, suggest that AMF could undergo a complete sexual reproduction cycle.
Hone, Liana S E; McCullough, Michael
Drinking games are a risk factor for behavioral and health problems among university students. Previous cross-sectional research by Hone, Carter, and McCullough (2013) replicated well-established sex differences in drinking game behaviors (i.e., that men are more active drinking game participants than are women) and university drinking problems more generally. Hone et al. (2013) also found that these male-specific behavioral patterns are attributable in part to the fact that men's generally unrestricted sexual strategies, plus their social competitiveness, motivate them to participate in drinking games to display their fortitude and compete with same-sex rivals. Here, the authors conducted a study to evaluate with greater causal rigor whether sex differences in sexual restrictedness and social competitiveness-and sex differences in motivations for participating in drinking games in particular-are partially responsible for the sex differences in university students' drinking game behaviors and drinking problems. Sex differences in changes in frequency of drinking game participation were partially mediated by competitive motivations for participating in drinking games and by the effects of social competitiveness on competitive drinking game motivation. These findings lend additional support to the proposition that participation in drinking games is motivated in part by their suitability as a venue for sexual competition in university students' day-to-day lives.
Liana S. E. Hone
Full Text Available Drinking games are a risk factor for behavioral and health problems among university students. Previous cross-sectional research by Hone, Carter, and McCullough (2013 replicated well-established sex differences in drinking game behaviors (i.e., that men are more active drinking game participants than are women and university drinking problems more generally. Hone et al. (2013 also found that these male-specific behavioral patterns are attributable in part to the fact that men's generally unrestricted sexual strategies, plus their social competitiveness, motivate them to participate in drinking games to display their fortitude and compete with same-sex rivals. Here, the authors conducted a study to evaluate with greater causal rigor whether sex differences in sexual restrictedness and social competitiveness—and sex differences in motivations for participating in drinking games in particular—are partially responsible for the sex differences in university students' drinking game behaviors and drinking problems. Sex differences in changes in frequency of drinking game participation were partially mediated by competitive motivations for participating in drinking games and by the effects of social competitiveness on competitive drinking game motivation. These findings lend additional support to the proposition that participation in drinking games is motivated in part by their suitability as a venue for sexual competition in university students' day-to-day lives.
Barth, Robert J.; Kinder, Bill N.
Investigates sex differences in same-sex friendships of 312 undergraduate students in terms of the intersection and social penetration model of relationship development, and Bem's theory of sex role orientation. Finds significant sex-related differences in depth, duration, and involvement. (FMW)
Full Text Available Ahmad Delbari,1 Farzane Keyghobadi,2 Yadollah Abolfathi Momtaz,1,3 Fariba Keyghobadi,2 Reza Akbari,2 Houman Kamranian,2 Mohammad Shouride Yazdi,2 Sayed Shahaboddin Tabatabaei,1 Seyed-Mohammad Fereshtehnejad4 1Iranian Research Center on Aging, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran; 2Research Center on Healthy Aging, Sabzevar University of Medical Sciences, Sabzevar, Khorasan, Iran; 3Malaysian Research Institute on Ageing (MyAgeing™, Universiti Putra Malaysia, Serdang, Selangor, Malaysia; 4Department of Neurobiology, Division of Clinical Geriatrics, Care Sciences and Society (NVS, Karolinska Institutet, Stockholm, Sweden Background: A number of studies have explored the issue of sex differences in stroke from biomedical perspective; however, there are still large gaps in the existing knowledge. The purpose of this study was to assess whether the differences in socioeconomic status and living conditions between men and women may explain the part of the sex differences in incidence and outcomes of stroke. Methods: All stroke participants aged ≥60 years admitted in Vaseie Hospital in Sabzevar, Iran, from March 21, 2013, until March 20, 2014, were included in this study. Computerized tomography and magnetic resonance imaging were used to confirm stroke. A series of χ2 tests were performed and Statistical Program for Social Sciences, Version 21.0, was used to investigate the potential differences between older men and women in stroke incidence and outcomes. Results: A total of 159 incident stroke cases were documented during 1 year. The annual rate of stroke was statistically significantly higher in elderly women than in elderly men (401 vs 357 per 100,000; P<0.001. Female elderly participants had significantly lower socioeconomic status, poorer living conditions, and higher lifetime history of depression, hypertension, and diabetes mellitus than their male counterparts. Conclusion: The findings from this study
Cross, Catharine P
Sex differences in same-sex direct aggression and sociosexuality are among the most robust in the literature. The present article evaluated the hypothesis that both can be explained by a sex difference in the willingness to take impulsive risks. Self-report data were gathered from 3,775 respondents (1,514 female) on same-sex aggression, sociosexuality, and risky impulsivity. Risky impulsivity was higher for men than for women (d = .34) and path analysis showed it to be a common cause of same-sex aggression and sociosexuality for both sexes. However, it did not completely mediate the sex differences in same-sex aggression and sociosexuality. The results suggest that same-sex aggression and sociosexual behavior share a common psychological mechanism, but that fully explaining sex differences in aggression requires a more sensitive assay of impulsive risk and a consideration of dyadic processes.
Catharine P. Cross
Full Text Available Sex differences in same-sex direct aggression and sociosexuality are among the most robust in the literature. The present article evaluated the hypothesis that both can be explained by a sex difference in the willingness to take impulsive risks. Self-report data were gathered from 3,775 respondents (1,514 female on same-sex aggression, sociosexuality, and risky impulsivity. Risky impulsivity was higher for men than for women (d = .34 and path analysis showed it to be a common cause of same-sex aggression and sociosexuality for both sexes. However, it did not completely mediate the sex differences in same-sex aggression and sociosexuality. The results suggest that same-sex aggression and sociosexual behavior share a common psychological mechanism, but that fully explaining sex differences in aggression requires a more sensitive assay of impulsive risk and a consideration of dyadic processes.
Public discourses around ‘migrant sex workers’ are often more confident about what migrant sex workers signify morally (i.e. vulnerability, criminality) but are less clear about who the ‘migrant’ is. This thesis interrogates the implications of the ‘migrant sex worker’ category based on semi-structured interviews with 65 immigrant, migrant and racialised women in sex work and two support staff in Melbourne, Australia and Vancouver, Canada during 2013–2014. Specifically, I employ an intersecti...
Stebbins, Charles; And Others
Validates the "College Self-Expression Scale." Shows that females are significantly more assertive, and that in one of the criterion situations each sex was significantly more assertive toward members of the same sex than members of the opposite sex. (RL)
Whissell, C; McCall, L
Advertisements in men's, women's, girls', and boys' magazines (n = 38,195 words) were scored objectively in terms of 15 measures of linguistic style, e.g., use of common words, use of long words, use of specific words and emotional tone (pleasantness and activation, as measured by the Dictionary of Affect). There were several sex- and age-related differences among advertisements from different sources. Advertisements from boys' magazines were extremely active, those from women's and girls' magazines were shorter and unusually pleasant. In two follow-up studies (N = 122 volunteers), objective emotional measures of advertising text proved to be related to ratings of persuasion and of success of appeal for individual advertisements. The most preferred advertisement for women was pleasant and active, that for men unpleasant and active. When men and women created advertisements, women's were shorter and more pleasant.
Krause, A.E.; Eshenroder, R.L.; Begnoche, L.J.
We analyzed buoyancy in two deepwater ciscoes, Coregonus hoyi and C. kiyi, and in C. artedi, their putative ancestor, and also analyzed how variations in fish weight, water content, and lipid content affected buoyancy. Buoyancy was significantly different among the three species (p < 0.0001). Estimates of percent buoyancy (neutral buoyancy = 0.0%) were: kiyi, 3.8%; hoyi, 4.7%; and artedi, 5.7%. Buoyancy did not change with fish weight alone (p = 0.38). Fish weight was negatively related to water content for all three species (p = 0.037). Lipid content was not significantly different between hoyi and kiyi, but artedi had significantly fewer lipids than hoyi and kiyi (p < 0.10). When artedi was removed from the analysis, fish weight and lipids accounted for 48% of the variation in buoyancy (p = 0.003), fatter hoyi were less dense than leaner hoyi, but fatter and leaner kiyi were no different in density. Our findings provide additional evidence that buoyancy regulation was a speciating mechanism in deepwater ciscoes and that kiyi is more specialized than hoyi for diel-vertical migration in deep water.
In the last decade, a number of studies have reported sex differences in selective attention, but a unified explanation for these effects is still missing. This study aims to better understand these differences and put them in an evolutionary psychological context. 418 adult participants performed a computer-based Simon task, in which they responded to the direction of a left or right pointing arrow appearing left or right from a fixation point. Women were more strongly influenced by task-irrelevant spatial information than men (i.e., the Simon effect was larger in women, Cohen's d = 0.39). Further, the analysis of sex differences in behavioral adjustment to errors revealed that women slow down more than men following mistakes (d = 0.53). Based on the combined results of previous studies and the current data, it is proposed that sex differences in selective attention are caused by underlying sex differences in core abilities, such as spatial or verbal cognition.
Dawson, Samantha J; Bannerman, Brittany A; Lalumière, Martin L
Little research has been conducted to examine paraphilic sexual interests in nonclinical samples. The little that exists suggests that atypical sexual interests are more common in men than in women, but the reasons for this difference are unknown. In this study, we explored the prevalence of paraphilic interests in a nonclinical sample of men and women. We expected that men would report greater arousal (or less repulsion) toward various paraphilic acts than women. We also examined putative correlates of paraphilias in an attempt to explain the sex difference. In all, 305 men and 710 women completed an online survey assessing sexual experiences, sexual interests, as well as indicators of neurodevelopmental stress, sex drive, mating effort, impulsivity, masculinity/femininity, and socially desirable responding. As expected, significant sex differences were found, with men reporting significantly less repulsion (or more arousal) to the majority of paraphilic acts than women. Using mediation analysis, sex drive was the only correlate to significantly and fully mediate the sex difference in paraphilic interests. In other words, sex drive fully accounted for the sex difference in paraphilic interests. The implications of these findings for understanding the etiology of atypical sexual interests are discussed. © The Author(s) 2014.
Full Text Available Snapchat offers a distinctive feature from other social networks in that its users control the visibility of the contents they share with others by defining how long these contents may be available. Snapchat is changing the way men and women perceive online information privacy and content management. This paper aims to illustrate the relevance of social representation theory to evaluate perceived privacy in Snapchat users, with a sample of 268 young adults residing in Bogotá. A survey method was employed for data collection purposes. The results reveal that Snapchat users are concerned about their networks’ privacy, with no significant sex differences, although men's perception of Snapchat privacy is safer than that of women. Finally, a discussion is presented as to the limitations and implications of these results for further studies.
Swaab, D. F.; Chung, W. C.; Kruijver, F. P.; Hofman, M. A.; Ishunina, T. A.
Sex differences in the brain may be the basis not only for sex differences in reproduction, gender identity (the feeling of being male or female), and sexual orientation (heterosexuality vs homosexuality), but also for the sex difference in prevalence of psychiatric and neurological diseases ( Swaab
Manning, Wendy D; Brown, Susan L; Stykes, J Bart
Relationship stability is a key indicator of well-being, but most U.S.-based research has been limited to different-sex couples. The 2008 panel of the Survey of Income and Program Participation (SIPP) provides an untapped data resource to analyze relationship stability of same-sex cohabiting, different-sex cohabiting, and different-sex married couples (n = 5,701). The advantages of the SIPP data include the recent, nationally representative, and longitudinal data collection; a large sample of same-sex cohabitors; respondent and partner socioeconomic characteristics; and identification of a state-level indicator of a policy stating that marriage is between one man and one woman (i.e., DOMA). We tested competing hypotheses about the stability of same-sex versus different-sex cohabiting couples that were guided by incomplete institutionalization, minority stress, relationship investments, and couple homogamy perspectives (predicting that same-sex couples would be less stable) as well as economic resources (predicting that same-sex couples would be more stable). In fact, neither expectation was supported: results indicated that same-sex cohabiting couples typically experience levels of stability that are similar to those of different-sex cohabiting couples. We also found evidence of contextual effects: living in a state with a constitutional ban against same-sex marriage was significantly associated with higher levels of instability for same- and different-sex cohabiting couples. The level of stability in both same-sex and different-sex cohabiting couples is not on par with that of different-sex married couples. The findings contribute to a growing literature on health and well-being of same-sex couples and provide a broader understanding of family life.
Andersen, ML; Sawyer, EK; Howell, LL
A consistent observation in drug abuse research is that males and females show differences in their response to drugs of abuse. In order to understand the neurobiology underlying cocaine abuse and effective treatments, it is important to consider the role of sex differences. Sex hormones have been investigated in both behavioral and molecular studies, but further evidence addressing drug abuse and dependence in both sexes would expand our knowledge of sex-differences in response to drugs of a...
In the last decade, a number of studies have reported sex differences in selective attention, but a unified explanation for these effects is still missing. This study aims to better understand these differences and put them in an evolutionary psychological context. 418 adult participants performed a computer-based Simon task, in which they responded to the direction of a left or right pointing arrow appearing left or right from a fixation point. Women were more strongly influenced by task-irr...
Barrett, Carol J.
Previous writers have presumed that widowhood is more stressful for one sex or the other. Hypotheses derived from demographic considerations and sex role developmental theory compared the needs and resources of 147 widows and 42 widowers, relative to 190 married persons. All subjects were non-institutionalized urban residents aged 62 or over. The…
Sons, 1977. 6 15. Horn, J, L. Human abilities: A review of research and theory in the early 1970’s. Annual Review of Psychology. 1976, 27^, 437...Mother-Infant Interaction, Howard A. Moss. 149. Sex of Parent X Sex of Child: Socioemotional Development, Micheal Lewis and Marsha Weinraub. 165...C. Thomas, 1971. Contents: Biology of Sex Differences. 3. Psychological Sex Differences. 12. Freudian Theory of Feminine Development. 43. The
Estes, Zachary; Felker, Sydney
On tasks that require the mental rotation of 3-dimensional figures, males typically exhibit higher accuracy than females. Using the most common measure of mental rotation (i.e., the Mental Rotations Test), we investigated whether individual variability in confidence mediates this sex difference in mental rotation performance. In each of four experiments, the sex difference was reliably elicited and eliminated by controlling or manipulating participants' confidence. Specifically, confidence predicted performance within and between sexes (Experiment 1), rendering confidence irrelevant to the task reliably eliminated the sex difference in performance (Experiments 2 and 3), and manipulating confidence significantly affected performance (Experiment 4). Thus, confidence mediates the sex difference in mental rotation performance and hence the sex difference appears to be a difference of performance rather than ability. Results are discussed in relation to other potential mediators and mechanisms, such as gender roles, sex stereotypes, spatial experience, rotation strategies, working memory, and spatial attention.
da Silva, L A; Lin, S M; Teixeira, M J; de Siqueira, J T T; Jacob Filho, W; de Siqueira, S R D T
To investigate age and sex differences in orofacial sensory detection. One hundred and twenty-six (126) healthy subjects were divided into five groups according to their ages. They were assessed with a quantitative sensory testing protocol for gustative, olfactory, thermal (cold/warm), mechanical (tactile/vibration/electric), and pain (deep/superficial) detection thresholds. The corneal reflex was also evaluated. Data were analyzed with the one-way ANOVA, chi-squared, Fisher's exact, Mann-Whitney, and Kruskal-Wallis tests. The groups of subjects over 61 years old had higher olfactory (P sweet P = 0.004, salty P = 0.007, sour P = 0.006), thermal (warm P sweet P = 0.020, salty P = 0.002, sour P < 0.001, and bitter P = 0.002), olfactory (P = 0.010), warm (P < 0.001) and deep (P < 0.001), and superficial pain (P = 0.008) detection thresholds than men, and men from all age groups had lower vibratory detection thresholds (P = 0.006) than women. High sensory detection thresholds were observed in subjects over the 6th decade of life, and women had a more accurate sensory perception than men. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Sramek, John J; Murphy, Michael F; Cutler, Neal R
Although a number of studies have observed that females respond better to serotonergic antidepressants than males and that postmenopausal females have a diminished response to antidepressants compared with younger females, there are also studies that conflict with both of these findings, making any generalizations regarding sex differences difficult to make. Sex variance in antidepressant efficacy and pharmacokinetics profiles have been attributed to sex-based physiological differences, behavioral differences, related disorders, and sex-specific conditions, including pregnancy and menopause. This paper will review the history and current research on sex effects of antidepressant treatment.
Sanchis-Segura, Carla; Becker, Jill B
Among mammals, every cell has a biological sex, and the sex of an individual pervades its body and brain. In this review, we describe the processes through which mammals become phenotypically male or female by organizational and activational influences of genes and hormones throughout development. We emphasized that the molecular and cellular changes triggered by sex chromosomes and steroid hormones may generate sex differences in overt physiological functions and behavior, but they may alternatively promote end-point convergences between males and females. Clinical and pre-clinical evidences suggest that sex and gender differences modulate drug consumption as well as of the transition towards drug-promoted pathological states such as dependence and addiction. Additionally, sex differences in drug pharmacokinetics and pharmacodynamics will also influence dependence and addiction as well as side effects of drugs. These effects will further interact with socially gendered factors to result in sex differences in the access to, engagement in and efficacy of any therapeutic attempt. Finally, we maintain that 'sex sameness' is as important as 'sex differences' when building a complete understanding of biology for both males and females and provide a framework with which to classify and guide investigation into the mechanisms mediating sex differences and sex sameness. © 2016 Society for the Study of Addiction.
Full Text Available Sexual dimorphism in common disease is pervasive, including a dramatic male preponderance in autism spectrum disorders (ASDs. Potential genetic explanations include a liability threshold model requiring increased polymorphism risk in females, sex-limited X-chromosome contribution, gene-environment interaction driven by differences in hormonal milieu, risk influenced by genes sex-differentially expressed in early brain development, or contribution from general mechanisms of sexual dimorphism shared with secondary sex characteristics. Utilizing a large single nucleotide polymorphism (SNP dataset, we identify distinct sex-specific genome-wide significant loci. We investigate genetic hypotheses and find no evidence for increased genetic risk load in females, but evidence for sex heterogeneity on the X chromosome, and contribution of sex-heterogeneous SNPs for anthropometric traits to ASD risk. Thus, our results support pleiotropy between secondary sex characteristic determination and ASDs, providing a biological basis for sex differences in ASDs and implicating non brain-limited mechanisms.
Jennings, Wesley G.; Maldonado-Molina, Mildred M.; Piquero, Alex R.; Odgers, Candice L.; Bird, Hector; Canino, Glorisa
Although sex is one of the strongest correlates of crime, contentions remain regarding the necessity of sex-specific theories of crime. The current study examines delinquent trajectories across sex among Puerto Rican youth socialized in two different cultural contexts (Bronx, United States; and San Juan, Puerto Rico). Results indicate similar…
Carson, James A; Manolagas, Stavros C
Estrogens and androgens influence the growth and maintenance of bones and muscles and are responsible for their sexual dimorphism. A decline in their circulating levels leads to loss of mass and functional integrity in both tissues. In the article, we highlight the similarities of the molecular and cellular mechanisms of action of sex steroids in the two tissues; the commonality of a critical role of mechanical forces on tissue mass and function; emerging evidence for an interplay between mechanical forces and hormonal and growth factor signals in both bones and muscles; as well as the current state of evidence for or against a cross-talk between muscles and bone. In addition, we review evidence for the parallels in the development of osteoporosis and sarcopenia with advancing age and the potential common mechanisms responsible for the age-dependent involution of these two tissues. Lastly, we discuss the striking difference in the availability of several drug therapies for the prevention and treatment of osteoporosis, as compared to none for sarcopenia. This article is part of a Special Issue entitled "Muscle Bone Interactions". Published by Elsevier Inc.
Salvatore, Jessica E; Cho, Seung Bin; Dick, Danielle M
The study of sex differences has been identified as one way to enhance scientific reproducibility, and the National Institutes of Health (NIH) have implemented a new policy to encourage the explicit examination of sex differences. Our goal here is to address sex differences in behavioral genetic research on alcohol outcomes. We review sex differences for alcohol outcomes and whether the source and magnitude of genetic influences on alcohol consumption and alcohol use disorder (AUD) are the same across sexes; describe common research designs for studying sex-specific gene-by-environment interaction (G × E) effects; and discuss the role of statistical power and theory when testing sex-specific genetic effects. There are robust sex differences for many alcohol outcomes. The weight of evidence suggests that the source and magnitude of genetic influences on alcohol consumption and AUD are the same across sexes. Whether there are sex-specific G × E effects has received less attention to date. The new NIH policy necessitates a systematic approach for studying sex-specific genetic effects in alcohol research. Researchers are encouraged to report power for tests of these effects and to use theory to develop testable hypotheses, especially for studies of G × E.
Cowell, Whitney J; Wright, Rosalind J
Environmental toxicants and psychosocial stressors share many biological substrates and influence overlapping physiological pathways. Increasing evidence indicates stress-induced changes to the maternal milieu may prime rapidly developing physiological systems for disruption by concurrent or subsequent exposure to environmental chemicals. In this review, we highlight putative mechanisms underlying sex-specific susceptibility of the developing neuroendocrine system to the joint effects of stress or stress correlates and environmental toxicants (bisphenol A, alcohol, phthalates, lead, chlorpyrifos, and traffic-related air pollution). We provide evidence indicating that concurrent or tandem exposure to chemical and non-chemical stressors during windows of rapid development is associated with sex-specific synergistic, potentiated and reversed effects on several neuroendocrine endpoints related to hypothalamic-pituitary-adrenal axis function, sex steroid levels, neurotransmitter circuits, and innate immune function. We additionally identify gaps, such as the role that the endocrine-active placenta plays, in our understanding of these complex interactions. Finally, we discuss future research needs, including the investigation of non-hormonal biomarkers of stress. We demonstrate multiple physiologic systems are impacted by joint exposure to chemical and non-chemical stressors differentially among males and females. Collectively, the results highlight the importance of evaluating sex-specific endpoints when investigating the neuroendocrine system and underscore the need to examine exposure to chemical toxicants within the context of the social environment.
Majeres, Raymond L.
Three experiments were conducted with 91 male and 91 female university students to assess sex differences in performance on speeded matching tests and theory on same-different judgments. Results are interpreted via the dual-process hypothesis of same-difference judgments with sex differences explained in terms of serial comparison processes rather…
Dalla, Christina; Shors, Tracey J
Males and females learn and remember differently at different times in their lives. These differences occur in most species, from invertebrates to humans. We review here sex differences as they occur in laboratory rodent species. We focus on classical and operant conditioning paradigms, including classical eyeblink conditioning, fear-conditioning, active avoidance and conditioned taste aversion. Sex differences have been reported during acquisition, retention and extinction in most of these paradigms. In general, females perform better than males in the classical eyeblink conditioning, in fear-potentiated startle and in most operant conditioning tasks, such as the active avoidance test. However, in the classical fear-conditioning paradigm, in certain lever-pressing paradigms and in the conditioned taste aversion, males outperform females or are more resistant to extinction. Most sex differences in conditioning are dependent on organizational effects of gonadal hormones during early development of the brain, in addition to modulation by activational effects during puberty and adulthood. Critically, sex differences in performance account for some of the reported effects on learning and these are discussed throughout the review. Because so many mental disorders are more prevalent in one sex than the other, it is important to consider sex differences in learning when applying animal models of learning for these disorders. Finally, we discuss how sex differences in learning continue to alter the brain throughout the lifespan. Thus, sex differences in learning are not only mediated by sex differences in the brain, but also contribute to them.
John E. Edlund
Full Text Available The present studies address two criticisms of the theory of evolved sex differences in jealousy: (a that the sex difference in jealousy emerges only in response to hypothetical infidelity scenarios, and (b that the sex difference emerges only using forced-choice measures. In two separate studies, one a paper-and-pencil survey with a student sample and the other a web-based survey targeting a non-student sample, men and women showed significant sex differences in jealousy in response to actual infidelity experiences; men experienced more jealousy in response to the sexual aspects of an actual infidelity, whereas women experienced more jealousy in response to the emotional aspects of the infidelity. Sex differences emerged using both continuous measures of jealousy as well as the traditional forced-choice measure. Overall, our results demonstrate that sex differences in jealousy are not limited to responses to hypothetical infidelity scenarios; they also emerge in response to actual infidelity experiences.
Juel Ahrenfeldt, Linda; Lindahl-Jacobsen, Rune; Möller, Sören
(RCOPE) for the assessment of positive and negative religious coping patterns. Differences between OS and SS twins were investigated using logistic regression for each sex. The analyses were adjusted for dependence within twin pairs. No significant differences in religiousness and religious coping were......Sex differences in religion are well known, with females generally being more religious than males, and shared environmental factors have been suggested to have a large influence on religiousness. Twins from opposite-sex (OS) and same-sex (SS) pairs may differ because of a dissimilar psycho...
Oksuzyan, Anna; Drefahl, Sven; Jacobsen, Rune
migrant effect and predominantly male migration from non-Western countries to Denmark and Sweden in 1960-70s, as well as high fertility in their female spouses, we expect to find even smaller sex differential mortality among migrants than in the ethnic Danish and Swedish populations. We use high...
Strimbu, Jerry L.; And Others
Determines patterns of drug usage and related behavior of college, university, and junior college students on a state-wide basis. This article focuses on sex as it relates to the total pattern of drug abuse of nine specific substances among a large group of college students and examines results in terms of both practical and statistical…
Yokota, Yukifumi; Fujino, Nobuyuki; Sato, Yoshiaki; Matsunobu, Akira; Tadokoro, Mamoru [Sagamihara Kyodo Hospital (Japan); Akane, Atsushi [Kansai Medical College, Osaka (Japan); Matsuura, Nobuo; Maeda, Tohru [Kitasato Univ. (Japan); Nakahori, Yutaka; Nakagome, Yasuo [Univ. of Tokyo (Japan)
We report on twins of unlike sex who shared a 45,X/46,X, +mar karyotype. The mar chromosome was found to be Yq- by DNA analysis. Marker studies, including 8 VNTR loci, yielded a probability of monozygosity of 0.99999996. 16 refs., 1 fig., 1 tab.
Bangasser, Debra A; Valentino, Rita J
Stress is associated with the onset and severity of several psychiatric disorders that occur more frequently in women than men, including posttraumatic stress disorder (PTSD) and depression. Patients with these disorders present with dysregulation of several stress response systems, including the neuroendocrine response to stress, corticolimbic responses to negatively valenced stimuli, and hyperarousal. Thus, sex differences within their underlying circuitry may explain sex biases in disease prevalence. This review describes clinical studies that identify sex differences within the activity of these circuits, as well as preclinical studies that demonstrate cellular and molecular sex differences in stress responses systems. These studies reveal sex differences from the molecular to the systems level that increase endocrine, emotional, and arousal responses to stress in females. Exploring these sex differences is critical because this research can reveal the neurobiological underpinnings of vulnerability to stress-related psychiatric disorders and guide the development of novel pharmacotherapies. Copyright © 2014 Elsevier Inc. All rights reserved.
DeSteno, David; Bartlett, Monica Y; Braverman, Julia; Salovey, Peter
Two studies are presented that challenge the evidentiary basis for the existence of evolved sex differences in jealousy. In opposition to the evolutionary view, Study I demonstrated that a sex difference in jealousy resulting from sexual versus emotional infidelity is observed only when judgments are recorded using a forced-choice response format. On all other measures, no sex differences were found; both men and women reported greater jealousy in response to sexual infidelity. A second study revealed that the sex difference on the forced-choice measure disappeared under conditions of cognitive constraint. These findings suggest that the sex difference used to support the evolutionary view of jealousy (e.g., D. M. Buss, R. Larsen, D. Westen, & J. Semmelroth, 1992; D. M. Buss et al., 1999) likely represents a measurement artifact resulting from a format-induced effortful decision strategy and not an automatic, sex-specific response shaped by evolution.
John E. Edlund; Jeremy D. Heider; Cory R. Scherer; Maria-Magdalena Farc; Brad J. Sagarin
The present studies address two criticisms of the theory of evolved sex differences in jealousy: (a) that the sex difference in jealousy emerges only in response to hypothetical infidelity scenarios, and (b) that the sex difference emerges only using forced-choice measures. In two separate studies, one a paper-and-pencil survey with a student sample and the other a web-based survey targeting a non-student sample, men and women showed significant sex differences in jealousy in response to actu...
Rhen, T; Metzger, K; Schroeder, A; Woodward, R
Modes of sex determination are quite variable in vertebrates. The developmental decision to form a testis or an ovary can be influenced by one gene, several genes, environmental variables, or a combination of these factors. Nevertheless, certain morphogenetic aspects of sex determination appear to be conserved in amniotes. Here we clone fragments of nine candidate sex-determining genes from the snapping turtle Chelydra serpentina, a species with temperature-dependent sex determination (TSD). We then analyze expression of these genes during the thermosensitive period of gonad development. In particular, we compare gene expression profiles in gonads from embryos incubated at a male-producing temperature to those from embryos at a female-producing temperature. Expression of Dmrt1 and Sox9 mRNA increased gradually at the male-producing temperature, but was suppressed at the female-producing temperature. This finding suggests that Dmrt1 and Sox9 play a role in testis development. In contrast, expression of aromatase, androgen receptor (Ar), and Foxl2 mRNA was constant at the male-producing temperature, but increased several-fold in embryos at the female-producing temperature. Aromatase, Ar, and Foxl2 may therefore play a role in ovary development. In addition, there was a small temperature effect on ER alpha expression with lower mRNA levels found in embryos at the female-producing temperature. Finally, Dax1, Fgf9, and SF-1 were not differentially expressed during the sex-determining period, suggesting these genes are not involved in sex determination in the snapping turtle. Comparison of gene expression profiles among amniotes indicates that Dmrt1 and Sox9 are part of a core testis-determining pathway and that Ar, aromatase, ER alpha, and Foxl2 are part of a core ovary-determining pathway. 2007 S. Karger AG, Basel
van Grootheest, D.S.; Beekman, A.T.F.; Broese Van Groenou, M.I.; Deeg, D.J.H.
Background: This study focuses on sex differences in depression of the widowed. Previous research showed different results in sex differences and in depression after bereavement. We assessed the effects of widowhood on depressive symptoms for men and women and examined whether environmental strain
Clements, A. M.; Rimrodt, S. L.; Abel, J. R.; Blankner, J. G.; Mostofsky, S. H.; Pekar, J. J.; Denckla, M. B.; Cutting, L. E.
Sex differences on language and visuospatial tasks are of great interest, with differences in hemispheric laterality hypothesized to exist between males and females. Some functional imaging studies examining sex differences have shown that males are more left lateralized on language tasks and females are more right lateralized on visuospatial…
Maria Julia Scerbo
Full Text Available The organizational action of testosterone during critical periods of development is the cause of numerous sex differences in the brain. However, sex differences in neuritogenesis have been detected in primary neuronal hypothalamic cultures prepared before the peak of testosterone production by fetal testis. In the present study we assessed the hypothesis of that cell-autonomous action of sex chromosomes can differentially regulate the expression of the neuritogenic gene neurogenin 3 (Ngn3 in male and female hypothalamic neurons, generating sex differences in neuronal development. Neuronal cultures were prepared from male and female E14 mouse hypothalami, before the fetal peak of testosterone. Female neurons showed enhanced neuritogenesis and higher expression of Ngn3 than male neurons. The silencing of Ngn3 abolished sex differences in neuritogenesis, decreasing the differentiation of female neurons. The sex difference in Ngn3 expression was determined by sex chromosomes, as demonstrated using the four core genotypes mouse model, in which a spontaneous deletion of the testis-determining gene Sry from the Y chromosome was combined with the insertion of the Sry gene onto an autosome. In addition, the expression of Ngn3, which is also known to mediate the neuritogenic actions of estradiol, was increased in the cultures treated with the hormone, but only in those from male embryos. Furthermore, the hormone reversed the sex differences in neuritogenesis promoting the differentiation of male neurons. These findings indicate that Ngn3 mediates both cell-autonomous actions of sex chromosomes and hormonal effects on neuritogenesis.
Donnelly, Rachel; Umberson, Debra; Kroeger, Rhiannon A.
Childhood adversity has enduring consequences for individuals throughout life, including increased reactivity to stress that may contribute to marital strain in adulthood. Past research on gendered experiences of heterosexual spouses raises questions about how the influence of childhood adversity might differ for men and women in same-sex marriages. We analyze dyadic diary data from 756 individuals in 106 male same-sex, 157 female same-sex, and 115 different-sex marriages to consider how childhood adversity moderates the association between daily stress and marital strain. Results suggest that the negative consequences of daily stress for marital strain are amplified by past childhood adversity with variation for men and women in same- and different-sex unions, such that women and those in same-sex marriages may experience some protection from the adverse consequences of childhood adversity.
Berbesque, J Colette; Marlowe, Frank W; Crittenden, Alyssa N
We investigate sex differences in frequencies of adults eating in a foraging population-the Hadza of Tanzania. We use eating frequency data from instantaneous scan observations of the Hadza, to see to how much sharing of foods taken back to camp compensates for the targeting of different foods by each sex while out foraging. Eating in camp differs by sex in terms of overall eating frequency, as well as in terms of diet composition (frequencies of eating each food type). We also control for sex-differences in time spent in camp and still find sex-differences in eating frequencies-women are observed eating significantly more frequently than men. There are also sex-differences in the eating frequencies of particular food types both with and without controlling for presence in camp. Finally, we use data on acquisition of each food type by sex and find that both sexes are more frequently observed eating women's foods in camp than men's foods. At least in the case of the Hadza, we see pronounced sex differences in the in-camp diet. Hadza men are eating a higher quality diet than are women, but women are able to eat far more frequently, and spend less time foraging than men. It is not yet clear whether a regular caloric intake of lower quality foods would be more beneficial for maintaining fecundity than a more variable diet consisting of higher quality foods. Copyright © 2011 Wiley-Liss, Inc.
Choi, Gi Won; Kim, Hak Jun; Kim, Tae Wan; Lee, Ji Wun; Park, Sung Bum; Kim, Jin Kak
With differences between the sexes in foot bone anatomy and ligamentous laxity, there is the possibility that the results of hallux valgus surgery may also differ between the sexes. We aimed to compare the results of hallux valgus surgery between the sexes. The authors retrospectively reviewed 60 males (66 feet) and 70 females (82 feet) who underwent distal or proximal chevron osteotomy for the treatment of hallux valgus deformity between June 2005 and December 2011. We compared the clinical and radiologic outcomes between the sexes. There were no statistically significant differences in demographics between the sexes. The mean American Orthopedic Foot and Ankle Society score, visual analogue scale for pain, and patient satisfaction at the last follow-up did not differ significantly between the sexes. The mean preoperative hallux valgus angle (HVA) and inter-metatarsal angle (IMA) were not significantly different between the sexes. At the last follow-up, the mean HVA was significantly greater in females (p=0.003) than in males; mean IMA was not significantly different between the sexes. The mean correction of HVA in males was significantly greater than that in females (p=0.014). There were no significant differences between the sexes regarding clinical outcomes after distal and proximal chevron osteotomy. However, male patients achieved greater correction of HVA than female patients. There is a possibility that sexual dimorphism of the foot may affect postoperative HVA.
Christiansen, Dorte Mølgaard
provides an overview of research on sex and gender differences in anxiety disorders ranging from the well-established female preponderance in prevalence and severity to possible sex differences in the risk and protective factors associated with anxiety, sex differences in the clinical presentation......Several studies have examined sex differences in different anxiety disorders. Females are repeatedly found to be more likely than males to suffer from anxiety in general and to be diagnosed with most anxiety disorders, including agoraphobia (AG), panic disorder (PD), separation anxiety (SA...... of anxiety disorders, and potential sex differences in the effectiveness of different treatments. The chapter contains suggestions for future research, including important questions that remain to be answered....
Hopcroft, Rosemary L.; Bradley, Dana Burr
The sex difference in depression is well documented in westernized, developed societies, although there has been little quantitative cross-cultural research on the topic. In this study, we use multilevel logit models to examine sex differences in depression across 29 countries using data from the World Values Survey. We find that in no country are…
Bermejo-Toro, Laura; Prieto-Ursúa, María
Although numerous studies have been carried out confirming high levels in symptomatology of stress and depression in the teaching profession, research focusing on sex differences in these problems has been both scarce and inconclusive. The aim of this study is to analyse differences with regards to sex in the incidence of absenteeism, work-related…
Sutton-Smith, B.; Rosenberg, B. G.
This paper deals with two sets of data-one that fails to find any long-term sex differences in adults, and another which seems to find such differences. The Berkeley Guidance Study offers longitudinal data in which no variables differentiate between the two sexes at all age levels. From these results, the authors conclude that the normal course of…
Background. The incidence of Nephrotic syndrome (NS) in Nigeria population remain undetermined. The sex differences in changes in lipoprotein levels in. NS. are not well defined. This study examines the sex differences in lipoprotein levels among Nigerian patients with the N.S.. Methods Of 79 patients seen ...
Kret, M.E.; de Gelder, B.
Interest in sex-related differences in psychological functioning has again come to the foreground with new findings about their possible functional basis in the brain. Sex differences may be one way how evolution has capitalized on the capacity of homologous brain regions to process social
Weafer, Jessica; de Wit, Harriet
Here, we review the evidence for sex differences in behavioral measures of impulsivity for both humans and laboratory animals. We focus on two specific components of impulsivity: impulsive action (i.e., difficulty inhibiting a prepotent response) and impulsive choice (i.e., difficulty delaying gratification). Sex differences appear to exist on these measures, but the direction and magnitude of the differences vary. In laboratory animals, impulsive action is typically greater in males than females, whereas impulsive choice is typically greater in females. In humans, women discount more steeply than men, but sex differences on measures of impulsive action depend on tasks and subject samples. We discuss implications of these findings as they relate to drug addiction. We also point out the major gaps in this research to date, including the lack of studies designed specifically to examine sex differences in behavioral impulsivity, and the lack of consideration of menstrual or estrous phase or sex hormone levels in the studies. © 2013.
Wallis, Amy; Butt, Henry; Ball, Michelle; Lewis, Donald P.; Bruck, Dorothy
ABSTRACT The microgenderome defines the interaction between microbiota, sex hormones and the immune system. Our recent research inferred support for the microgenderome by showing sex differences in microbiota-symptom associations in a clinical sample of patients with myalgic encephalomyelitis / chronic fatigue syndrome (ME/CFS). This addendum expands upon the sex-specific pattern of associations that were observed. Interpretations are hypothesized in relation to genera versus species-level an...
Nicola J. Fussell
Full Text Available An influential evolutionary account of romantic jealousy proposes that natural selection shaped a specific sexually-dimorphic psychological mechanism in response to relationship threat. However, this account has faced considerable theoretical and methodological criticism and it remains unclear whether putative sex differences in romantic jealousy actually exist and, if they do, whether they are consistent with its predictions. Given the multidimensional nature of romantic jealousy, the current study employed a qualitative design to examine these issues. We report the results of sixteen semi-structured interviews that were conducted with heterosexual men and women with the purpose of exploring the emotions, cognitions and behaviors that formed their subjective, lived experience in response to relationship threat. Interpretative phenomenological analysis revealed four super-ordinate themes (“threat appraisal”, “emotional episodes”, “sex-specific threat” and “forgive and forget” and unequivocal sex differences in romantic jealousy consistent with the evolutionary account. Self-esteem, particularly when conceptualized as an index of mate value, emerged as an important proximal mediator for both sexes. However, specific outcomes were dependent upon domains central to the individual's self concept that were primarily sex-specific. The findings are integrated within the context of existing self-esteem and evolutionary theory and future directions for romantic jealousy research are suggested.
Fussell, Nicola J; Stollery, Brian T
An influential evolutionary account of romantic jealousy proposes that natural selection shaped a specific sexually-dimorphic psychological mechanism in response to relationship threat. However, this account has faced considerable theoretical and methodological criticism and it remains unclear whether putative sex differences in romantic jealousy actually exist and, if they do, whether they are consistent with its predictions. Given the multidimensional nature of romantic jealousy, the current study employed a qualitative design to examine these issues. We report the results of sixteen semi-structured interviews that were conducted with heterosexual men and women with the purpose of exploring the emotions, cognitions and behaviors that formed their subjective, lived experience in response to relationship threat. Interpretative phenomenological analysis revealed four super-ordinate themes ("threat appraisal", "emotional episodes", "sex-specific threat" and "forgive and forget") and unequivocal sex differences in romantic jealousy consistent with the evolutionary account. Self-esteem, particularly when conceptualized as an index of mate value, emerged as an important proximal mediator for both sexes. However, specific outcomes were dependent upon domains central to the individual's self concept that were primarily sex-specific. The findings are integrated within the context of existing self-esteem and evolutionary theory and future directions for romantic jealousy research are suggested.
Brazil Reginaldo P
Full Text Available Lutzomyia (Lutzomyia cruzi has been named as a probable vector of Leishmania chagasi in Corumbá, Mato Grosso do Sul, Brazil. Taxonomically L. cruzi is closely related to the L. longipalpis species complex. Females of L. cruzi and L. longipalpis are morphologically indistinguishable and associated males must be examined carefully to confirm identifications. Chemical analysis hexane extracts of male L. cruzi has revealed the presence of a 9-methylgermacrene-B (C16, a homosesquiterpene (mw 218 previously shown to be the sex pheromone of one of the members of the L. longipalpis species complex.
Damoiseaux, Valerie A.; Proost, Johannes H.; Jiawan, Vincent C. R.; Melgert, Barbro N.
Women are twice as likely to develop depression as men. Moreover, the symptoms they experience also show sex differences: women tend to develop depression at an earlier age and show more severe symptoms than men. Likewise, the response to antidepressant pharmacotherapy appears to have sex
Hirnstein, Marco; Coloma Andrews, Lisa; Hausmann, Markus
Sex differences in specific cognitive abilities are well documented, but the biological, psychological, and sociocultural interactions that may underlie these differences are largely unknown. We examined within a biopsychosocial approach how gender stereotypes affect cognitive sex differences when adult participants were tested in mixed- or same-sex groups. A total of 136 participants (70 women) were allocated to either mixed- or same-sex groups and completed a battery of sex-sensitive cognitive tests (i.e., mental rotation, verbal fluency, perceptual speed) after gender stereotypes or gender-neutral stereotypes (control) were activated. To study the potential role of testosterone as a mediator for group sex composition and stereotype boost/threat effects, saliva samples were taken before the stereotype manipulation and after cognitive testing. The results showed the typical male and female advantages in mental rotation and verbal fluency, respectively. In general, men and women who were tested in mixed-sex groups and whose gender stereotypes had not been activated performed best. Moreover, a stereotype threat effect emerged in verbal fluency with reduced performance in gender stereotyped men but not women. Testosterone levels did not mediate the effects of group sex composition and stereotype threat nor did we find any relationship between testosterone and cognitive performance in men and women. Taken together, the findings suggest that an interaction of gender stereotyping and group sex composition affects the performance of men and women in sex-sensitive cognitive tasks. Mixed-sex settings can, in fact, increase cognitive performance as long as gender-stereotyping is prevented.
Jacqueline M Vink
Full Text Available We examined sex differences in familial resemblance for a broad range of behavioral, psychiatric and health related phenotypes (122 complex traits in children and adults. There is a renewed interest in the importance of genotype by sex interaction in, for example, genome-wide association (GWA studies of complex phenotypes. If different genes play a role across sex, GWA studies should consider the effect of genetic variants separately in men and women, which affects statistical power. Twin and family studies offer an opportunity to compare resemblance between opposite-sex family members to the resemblance between same-sex relatives, thereby presenting a test of quantitative and qualitative sex differences in the genetic architecture of complex traits. We analyzed data on lifestyle, personality, psychiatric disorder, health, growth, development and metabolic traits in dizygotic (DZ same-sex and opposite-sex twins, as these siblings are perfectly matched for age and prenatal exposures. Sample size varied from slightly over 300 subjects for measures of brain function such as EEG power to over 30,000 subjects for childhood psychopathology and birth weight. For most phenotypes, sample sizes were large, with an average sample size of 9027 individuals. By testing whether the resemblance in DZ opposite-sex pairs is the same as in DZ same-sex pairs, we obtain evidence for genetic qualitative sex-differences in the genetic architecture of complex traits for 4% of phenotypes. We conclude that for most traits that were examined, the current evidence is that same the genes are operating in men and women.
Wolleat, Patricia L.
Information processing theory could be made more sensitive to differences in career outcomes for males and females by (1) examining the nature of the career decision; (2) expanding the notion of information; (3) relating the vocational schema to the gender schema; and (4) noting whether variables are general, sex related, or sex specific. (SK)
Vink, J.M.; Bartels, M.; van Beijsterveldt, C.E.M.; van Dongen, J.; van Beek, J.H.D.A.; Distel, M.A.; de Moor, M.H.M.; Smit, D.J.A.; Minica, C.C.; Ligthart, R.S.L.; Geels, L.M.; Abdellaoui, A.; Middeldorp, C.M.; Hottenga, J.J.; Willemsen, G.; de Geus, E.J.C.; Boomsma, D.I.
We examined sex differences in familial resemblance for a broad range of behavioral, psychiatric and health related phenotypes (122 complex traits) in children and adults. There is a renewed interest in the importance of genotype by sex interaction in, for example, genome-wide association (GWA)
Evans, Suzette M; Reynolds, Brady
This special issue exemplifies one of the major goals of the current editor of Experimental and Clinical Psychopharmacology (Dr. Suzette Evans): to increase the number of manuscripts that emphasize females and address sex differences. Taken together, these articles represent a broad range of drug classes and approaches spanning preclinical research to treatment to better understand the role of sex differences in drug abuse. While not all studies found sex differences, we want to emphasize that finding no sex difference is just as important as confirming one, and should be reported in peer-reviewed journals. It is our intention and hope that this special issue will further advance scientific awareness about the importance of accounting for sex differences in the study of substance abuse. Participant sex is an essential variable to consider in developing a more comprehensive understanding of substance abuse. Rather than viewing investigating sex differences as burdensome, investigators should seize this opportune area ripe for innovative research that is long overdue. (c) 2015 APA, all rights reserved).
Craft, Rebecca M.; Clark, James L.; Hart, Stephen P.; Pinckney, Megan K.
Sex differences in reinforcing, analgesic and other effects of opioids have been demonstrated; however, the extent to which sex differences in motoric effects of opioids contribute to apparent sex differences in their primary effects is not known. The goal of this study was to compare the effects of the prototypic mu opioid agonist morphine on locomotor activity in male vs. female rats. Saline or morphine (1-10 mg/kg) was administered s.c. to adult Sprague-Dawley rats, which were placed into ...
Marco Del Giudice
Full Text Available A comprehensive evolutionary theory of sex differences will benefit from an accurate assessment of their magnitude across different psychological domains. This article shows that mainstream research has severely underestimated the magnitude of psychological sex differences; the reason lies in the common practice of measuring multidimensional differences one dimension at a time, without integrating them into a proper multivariate effect size (ES. Employing the Mahalanobis distance D (the multivariate generalization of Cohen's d results in more accurate, and predictably larger, estimates of overall sex differences in multidimensional constructs. Two real-world examples are presented: (1 In a published dataset on Big Five personality traits, sex differences on individual scales averaged d = .27, a typical ES conventionally regarded as “small.” However, the overall difference was D = .84 (disattenuated D = .98, implying considerable statistical separation between male and female distributions. (2 In a recent meta-analytic summary of sex differences in aggression, the individual ESs averaged d = .34. However, the overall difference was estimated at D = .75 – .80 (disattenuated D = .89–1.01. In many psychological domains, sex differences may be substantially larger than previously acknowledged.
Weafer, Jessica; de Wit, Harriet
Here, we review the evidence for sex differences in behavioral measures of impulsivity for both humans and laboratory animals. We focus on two specific components of impulsivity: impulsive action (i.e., difficulty inhibiting a prepotent response) and impulsive choice (i.e., difficulty delaying gratification). Sex differences appear to exist on these measures, but the direction and magnitude of the differences vary. In laboratory animals, impulsive action is typically greater in males than fem...
Elizabeth V Lonsdorf
Full Text Available The role of biological and social influences on sex differences in human child development is a persistent topic of discussion and debate. Given their many similarities to humans, chimpanzees are an important study species for understanding the biological and evolutionary roots of sex differences in human development. In this study, we present the most detailed analyses of wild chimpanzee infant development to date, encompassing data from 40 infants from the long-term study of chimpanzees at Gombe National Park, Tanzania. Our goal was to characterize age-related changes, from birth to five years of age, in the percent of observation time spent performing behaviors that represent important benchmarks in nutritional, motor, and social development, and to determine whether and in which behaviors sex differences occur. Sex differences were found for indicators of social behavior, motor development and spatial independence with males being more physically precocious and peaking in play earlier than females. These results demonstrate early sex differentiation that may reflect adult reproductive strategies. Our findings also resemble those found in humans, which suggests that biologically-based sex differences may have been present in the common ancestor and operated independently from the influences of modern sex-biased parental behavior and gender socialization.
Ramikie, Teniel Sonya; Ressler, Kerry J
Following sexual maturity, females disproportionately have higher rates of posttraumatic stress disorder (PTSD) and experience greater symptom severity and chronicity as compared with males. This observation has led many to examine sex differences in PTSD risk factors. Though relatively few, these studies reveal that the root causes of PTSD sex differences are complex, and partly represent interactions between sex-specific nonbiological and biological risk factors, which differentially shape PTSD vulnerability. Moreover, these studies suggest that sex-specific PTSD vulnerability is partly regulated by sex differences in fear systems. Fear, which represents a highly conserved adaptive response to threatening environmental stimuli, becomes pathological in trauma- and stress-based psychiatric syndromes, such as PTSD. Over the last 30 years, considerable progress has been made in understanding normal and pathological molecular and behavioral fear processes in humans and animal models. Thus, fear mechanisms represent a tractable PTSD biomarker in the study of sex differences in fear. In this review, we discuss studies that examine nonbiological and biological sex differences that contribute to normal and pathological fear behaviors in humans and animal models. This, we hope, will shed greater light on the potential mechanisms that contribute to increased PTSD vulnerability in females. Copyright © 2017 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.
Grigore, Daniela; Ojeda, Norma B; Alexander, Barbara T
Numerous clinical and experimental studies support the hypothesis that the intrauterine environment is an important determinant of cardiovascular disease and hypertension. This review examined the mechanisms linking an adverse fetal environment and increased risk for chronic disease in adulthood with an emphasis on gender differences and the role of sex hormones in mediating sexual dimorphism in response to a suboptimal fetal environment. This review focuses on current findings from the PubMed database regarding animal models of fetal programming of hypertension, sex differences in phenotypic outcomes, and potential mechanisms in offspring of mothers exposed to an adverse insult during gestation. For the years 1988 to 2007, the database was searched using the following terms: fetal programming, intrauterine growth restriction, low birth weight, sex differences, estradiol, testosterone, high blood pressure, and hypertension. The mechanisms involved in the fetal programming of adult disease are multifactorial and include alterations in the regulatory systems affecting the long-tterm control of arterial pressure. Sex differences have been observed in animal models of fetal programming, and recent studies suggest that sex hormones may modulate activity of regulatory systems, leading to a lower incidence of hypertension and vascular dysfunction in females compared with males. Animal models of fetal programming provide critical support for the inverse relationship between birth weight and blood pressure. Experimental models demonstrate that sex differences are observed in the pathophysiologic response to an adverse fetal environment. A role for sex hormone involvement is strongly suggested,with modulation of the renin-angiotensin system as a possible mechanism.
Scheinost, Dustin; Finn, Emily S; Tokoglu, Fuyuze; Shen, Xilin; Papademetris, Xenophon; Hampson, Michelle; Constable, R Todd
Resting-state functional magnetic resonance image (rs-fMRI) is increasingly used to study functional brain networks. Nevertheless, variability in these networks due to factors such as sex and aging is not fully understood. This study explored sex differences in normal age trajectories of resting-state networks (RSNs) using a novel voxel-wise measure of functional connectivity, the intrinsic connectivity distribution (ICD). Males and females showed differential patterns of changing connectivity in large-scale RSNs during normal aging from early adulthood to late middle-age. In some networks, such as the default-mode network, males and females both showed decreases in connectivity with age, albeit at different rates. In other networks, such as the fronto-parietal network, males and females showed divergent connectivity trajectories with age. Main effects of sex and age were found in many of the same regions showing sex-related differences in aging. Finally, these sex differences in aging trajectories were robust to choice of preprocessing strategy, such as global signal regression. Our findings resolve some discrepancies in the literature, especially with respect to the trajectory of connectivity in the default mode, which can be explained by our observed interactions between sex and aging. Overall, results indicate that RSNs show different aging trajectories for males and females. Characterizing effects of sex and age on RSNs are critical first steps in understanding the functional organization of the human brain. © 2014 Wiley Periodicals, Inc.
Fattore, Liana; Fratta, Walter
In humans as in animals, males and females are dissimilar in their genetic and hormonally driven behaviour; they process information differently, perceive experience and emotions in different ways, display diverse attitudes, language and social skills, and show sex-related differences in the brain anatomy and organization. Drug addiction is a widespread relapsing illness that affects both men and women. Sex-dependent differences have been frequently observed in the biological and behavioural effects of substances of abuse, including cannabis. Beside sex differences observed in the cannabinoid-induced effects related to cannabis abuse and dependence, cannabinoids have been shown to exert sex-dependent effects also in other physiological and behavioural aspects, such as food intake and energy balance (more evident in males), or anxiety and depression (more evident in females). Research has just begun to identify factors which could provide a neurobiological basis for gender-based differences in cannabinoid effects, among which, gonadal hormones seem to play a crucial role. Yet, cannabinoid pharmacodynamic and pharmacokinetic may also be important, as sex differences in cannabinoid effects might be due, at least in part, to differences in muscle mass and fat tissue distribution between males and females. Here, we will review both clinical and laboratory-based research evidence revealing important sex-related differences in cannabinoid effects, and put forward some suggestions for future studies to fill the gap in our knowledge of gender-specific bias in cannabinoid pharmacology.
Mogil, Jeffrey S; Bailey, Andrea L
It is a clinical reality that women make up the large majority of chronic pain patients, and there is now consensus from laboratory experiments that when differences are seen, women are more sensitive to pain than men. Research in this field has now begun to concentrate on finding explanations for this sex difference. Although sex differences in sociocultural, psychological, and experiential factors likely play important roles, evidence largely from animal studies has revealed surprisingly robust and often qualitative sex differences at low levels of the neuraxis. Although not yet able to affect clinical practice, the continued study of sex differences in pain may have important implications for the development of new analgesic strategies. Copyright © 2010 Elsevier B.V. All rights reserved.
Aanerud, Joel; Borghammer, Per; Rodell, Anders
cerebral blood flow and cerebral metabolic rate of oxygen as functions of age in healthy volunteers of both sexes. Cerebral metabolic rate of oxygen did not change with age for either sex and there were no differences of mean values of cerebral metabolic rate of oxygen between men and women in cerebral...... cortex. Women had significant decreases of cerebral blood flow as function of age in frontal and parietal lobes. Young women had significantly higher cerebral blood flow than men in frontal and temporal lobes, but these differences had disappeared at age 65. The absent sex difference of cerebral energy...... turnover suggests that the known differences of synaptic density between the sexes are counteracted by opposite differences of individual synaptic activity....
Huxley, Virginia H; Kemp, Scott S; Schramm, Christine; Sieveking, Steve; Bingaman, Susan; Yu, Yang; Zaniletti, Isabella; Stockard, Kevin; Wang, Jianjie
Endothelial dysfunction is an early hallmark of multiple disease states that also display sex differences with respect to age of onset, frequency, and severity. Results of in vivo studies of basal and stimulated microvascular barrier function revealed sex differences difficult to ascribe to specific cells or environmental factors. The present study evaluated endothelial cells (EC) isolated from macro- and/or microvessels of reproductively mature rats under the controlled conditions of low-passage culture to test the assumption that EC phenotype would be sex-independent. The primary finding was that EC, regardless of where they are derived, retain a sex-bias in low-passage culture, independent of varying levels of reproductive hormones. Implications of the work include the fallacy of expecting a universal set of mechanisms derived from study of EC from one sex and/or one vascular origin to apply uniformly to all EC under unstimulated conditions no less in the disease state. Vascular endothelial cells (EC) are heterogeneous with respect to phenotype reflecting at least organ of origin, location within the vascular network, and physical forces. Sex, as an independent influence on EC functions in health or etiology, susceptibility, and progression of dysfunction in numerous disease states, has been largely ignored. The current study focussed on EC isolated from aorta (macrovascular) and skeletal muscle vessels (microvascular) of age-matched male and female rats under identical conditions of short term (passage 4) culture. We tested the hypothesis that genomic sex would not influence endothelial growth, wound healing, morphology, lactate production, or messenger RNA and protein expression of key proteins (sex hormone receptors for androgen (AR) and oestrogen (ERα and ERβ); PECAM-1 and VE-CAD mediating barrier function; α v β 3 and N-Cadherin influencing matrix interactions; ICAM-1 and VCAM-1 mediating EC/white cell adhesion). The hypothesis was rejected as EC origin
McEwen, Bruce S; Milner, Teresa A
Sex hormones act throughout the entire brain of both males and females via both genomic and nongenomic receptors. Sex hormones can act through many cellular and molecular processes that alter structure and function of neural systems and influence behavior as well as providing neuroprotection. Within neurons, sex hormone receptors are found in nuclei and are also located near membranes, where they are associated with presynaptic terminals, mitochondria, spine apparatus, and postsynaptic densities. Sex hormone receptors also are found in glial cells. Hormonal regulation of a variety of signaling pathways as well as direct and indirect effects on gene expression induce spine synapses, up- or downregulate and alter the distribution of neurotransmitter receptors, and regulate neuropeptide expression and cholinergic and GABAergic activity as well as calcium sequestration and oxidative stress. Many neural and behavioral functions are affected, including mood, cognitive function, blood pressure regulation, motor coordination, pain, and opioid sensitivity. Subtle sex differences exist for many of these functions that are developmentally programmed by hormones and by not yet precisely defined genetic factors, including the mitochondrial genome. These sex differences and responses to sex hormones in brain regions, which influence functions not previously regarded as subject to such differences, indicate that we are entering a new era of our ability to understand and appreciate the diversity of gender-related behaviors and brain functions. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Barbui, Corrado; Nosè, Michela; Bindman, Jonathan; Schene, Aart; Becker, Thomas; Mazzi, Maria A.; Kikkert, Martijn; Camara, Jayne; Born, Anja; Tansella, Michele
In recent years, research efforts have been directed to better characterize the Subjective experience of taking psychotropic drugs. This Study investigated the sex difference in the subjective tolerability of antipsychotic drugs. Participants were recruited from patients under the care of
Bekker, Marrie H.J.; Van Assen, Marcel A.L.M.
Objectives: This study aimed to examine if autonomy-connectedness, capacity for self-governance under the condition of connectedness, would mediate sex differences in symptoms of various mental disorders (depression, anxiety, eating disorders, antisocial personality disorder). Method: Participants
Bekker, M.H.J.; van Assen, M.A.L.M.
Objectives This study aimed to examine if autonomy-connectedness, capacity for self-governance under the condition of connectedness, would mediate sex differences in symptoms of various mental disorders (depression, anxiety, eating disorders, antisocial personality disorder). Method Participants (N
Hausmann, Markus; Schoofs, Daniela; Rosenthal, Harriet E S; Jordan, Kirsten
Biological and social factors have been shown to affect cognitive sex differences. For example, several studies have found that sex hormones have activating effects on sex-sensitive tasks. On the other hand, it has been shown that gender stereotypes can influence the cognitive performance of (gender-) stereotyped individuals. However, few studies have investigated the combined effects of both factors. The present study investigated the interaction between sex hormones and gender stereotypes within a psychobiosocial approach. One hundred and fourteen participants (59 women) performed a battery of sex-sensitive cognitive tasks, including mental rotation, verbal fluency, and perceptual speed. Saliva samples were taken immediately after cognitive testing. Levels of testosterone (T) were analysed using chemiluminescence immunoassay (LIA). To activate gender stereotypes, a questionnaire was applied to the experimental group that referred to the cognitive tasks used. The control group received an identical questionnaire but with a gender-neutral content. As expected, significant sex differences favouring males and females appeared for mental rotation and verbal fluency tasks, respectively. The results revealed no sex difference in perceptual speed. The male superiority in the Revised Vandenberg and Kuse Mental Rotations Tests (MRT-3D) was mainly driven by the stereotype-active group. No significant sex difference in MRT-3D appeared in the control group. The MRT-3D was also the task in which a strong gender-stereotype favouring males was present for both males and females. Interestingly, T levels of the stereotype-activated group were 60% higher than that of male controls. The results suggest that sex hormones mediate the effects of gender stereotypes on specific cognitive abilities.
Cross, Catharine P; Cyrenne, De-Laine M; Brown, Gillian R
Men score higher than women on measures of sensation-seeking, defined as a willingness to engage in novel or intense activities. This sex difference has been explained in terms of evolved psychological mechanisms or culturally transmitted social norms. We investigated whether sex differences in sensation-seeking have changed over recent years by conducting a meta-analysis of studies using Zuckerman's Sensation Seeking Scale, version V (SSS-V). We found that sex differences in total SSS-V scores have remained stable across years, as have sex differences in Disinhibition and Boredom Susceptibility. In contrast, the sex difference in Thrill and Adventure Seeking has declined, possibly due to changes in social norms or out-dated questions on this sub-scale. Our results support the view that men and women differ in their propensity to report sensation-seeking characteristics, while behavioural manifestations of sensation-seeking vary over time. Sex differences in sensation-seeking could reflect genetically influenced predispositions interacting with socially transmitted information.
Margaret M Mccarthy; Bridget M Nugent
The notion that epigenetics may play an important role in the establishment and maintenance of sex differences in the brain has garnered great enthusiasm but the reality in terms of actual advances has been slow. Two general approaches include the comparison of a particular epigenetic mark in males vs. females and the inhibition of key epigenetic enzymes or co-factors to determine if this eliminates a particular sex difference in brain or behavior. The majority of emphasis has been on candida...
Romberg, Kerstin; Tufvesson, Ellen; Bjermer, Leif
Background: Elite athletes, independent of sport, have increased risk of developing asthma, but little is known about sex difference among adolescent athletes. Objective: To investigate and compare sex-related differences according to symptoms and treatment of asthma, allergy, and health among elite athletes and a reference group. Methods: Adolescent elite swimmers (n = 101), tennis players (n = 86), and a reference group (n = 1,628) responded to a questionnaire about respiratory symptoms, al...
Hanske-Petitpierre, V; Chen, A C
This article reviews current knowledge in two major research domains: sex differences in neuropsychophysiology, and in human communication. An attempt was made to integrate knowledge from several areas of brain research with human communication and to clarify how such a cooperative effort may be beneficial to both fields of study. By combining findings from the area of brain research, a communication paradigm was developed which contends that brain-related sex differences may reside largely in the area of communication of emotion.
Samba Reddy, Doodipala
Epilepsy is one of the leading causes of chronic neurological morbidity worldwide. Acquired epilepsy may result from a number of conditions such brain injury, anoxia, tumors, stroke, neurotoxicity, and prolonged seizures. Sex differences have been observed in many seizures types; however there are sex-specific seizure disorders that are much more prevalent in women. Despite some inconsistencies, there is a substantial amount of data which indicates that sensitivity to seizure stimuli differs ...
David, Sean P; Naudet, Florian; Laude, Jennifer; Radua, Joaquim; Fusar-Poli, Paolo; Chu, Isabella; Stefanick, Marcia L; Ioannidis, John P A
Numerous functional magnetic resonance imaging (fMRI) studies have reported sex differences. To empirically evaluate for evidence of excessive significance bias in this literature, we searched for published fMRI studies of human brain to evaluate sex differences, regardless of the topic investigated, in Medline and Scopus over 10 years. We analyzed the prevalence of conclusions in favor of sex differences and the correlation between study sample sizes and number of significant foci identified. In the absence of bias, larger studies (better powered) should identify a larger number of significant foci. Across 179 papers, median sample size was n = 32 (interquartile range 23-47.5). A median of 5 foci related to sex differences were reported (interquartile range, 2-9.5). Few articles (n = 2) had titles focused on no differences or on similarities (n = 3) between sexes. Overall, 158 papers (88%) reached "positive" conclusions in their abstract and presented some foci related to sex differences. There was no statistically significant relationship between sample size and the number of foci (-0.048% increase for every 10 participants, p = 0.63). The extremely high prevalence of "positive" results and the lack of the expected relationship between sample size and the number of discovered foci reflect probable reporting bias and excess significance bias in this literature.
Leif Edward Ottesen Kennair
Full Text Available Despite highly replicable predictable differences between the sexes on various sexual desires and attitudes, critics of evolutionary perspectives argue against the biological origins of such differences, highlighting cultural explanations. Critics suggest that there are no cross-cultural evolutionary predictable, systematic differences. Eagly and Wood (1999 suggest that in egalitarian cultures sex differences will be small or disappear. We tested whether Trivers’ (1972 Parental Investment Theory and Buss and Schmitt’s (1993 Sexual Strategies Theory predicted sex differences in sexuality within samples of students (N=1072 in egalitarian Norway. We expected similar interest in long-term relationships, but that females seek short-term partners less than males. Furthermore, males were expected to have less restricted sociosexuality, fantasize more, take more initiative to sex and be less satisfied with frequency of sex. The predictions were supported in the evolutionarily-predicted directions. Clinical consequences of claiming there are no sex differences in sexuality, when indeed they exist, are discussed.
Carroll, Marilyn E; Lynch, Wendy J
The importance of studying sex as a biological variable in biomedical research is becoming increasingly apparent. There is a particular need in preclinical studies of addiction to include both sexes, as female animals are often excluded from studies, leaving large gaps in our knowledge of not only sex differences and potential prevention and treatment strategies but also with regard to the basic neurobiology of addiction. This review focuses on methodology that has been developed in preclinical studies to examine sex differences in the behavioral aspects and neurobiological mechanisms related to addiction across the full range of the addiction process, including initiation (acquisition), maintenance, escalation, withdrawal, relapse to drug seeking and treatment. This review also discusses strategic and technical issues that need to be considered when comparing females and males, including the role of ovarian hormones and how sex differences interact with other major vulnerability factors in addiction, such as impulsivity, compulsivity and age (adolescent versus adult). Novel treatments for addiction are also discussed, such as competing non-drug rewards, repurposed medications such as progesterone and treatment combinations. Practical aspects of conducting research comparing female and male animals are also considered. Making sex differences a point of examination requires additional effort and consideration; however, such studies are necessary given mounting evidence demonstrating that the addiction process occurs differently in males and females. These studies should lead to a better understanding of individual differences in the development of addiction and effective treatments for males and females. © 2016 Society for the Study of Addiction.
Aubry, P; Demian, H
Gender influences the clinical presentation and the management of some acquired cardiovascular diseases, such as coronary artery disease, resulting in different outcomes. Differences between women and men are also noticed in congenital heart disease. They are mainly related to the prevalence and severity of some congenital heart defects at birth, and in adulthood to the prognosis, incidence of Eisenmenger syndrome and risks of pregnancy. The role of gender on the risk of operative mortality of congenital heart surgery remains debated. Copyright Â© 2016 Elsevier Masson SAS. All rights reserved.
Lozo, Tijana; Komnenov, Dragana; Badr, M Safwan; Mateika, Jason H
The prevalence of sleep disordered breathing is greater in men compared to women. This disparity could be due to sex differences in the diagnosis and presentation of sleep apnea, and the pathophysiological mechanisms that instigate this disorder. Women tend to report more non-typical symptoms of sleep apnea compared to men, and the presentation of apneic events are more prevalent in rapid compared to non-rapid eye movement sleep. In addition, there is evidence of sex differences in upper airway structure and mechanics and in neural mechanisms that impact on the control of breathing. The purpose of this review is to summarize the literature that addresses sex differences in sleep-disordered breathing, and to discuss the influence that upper airway mechanics, chemoreflex properties, and sex hormones have in modulating breathing during sleep in men and women. Published by Elsevier B.V.
Worldwide, many research has been performed to investigate differences between men and women with type 2 diabetes (T2D) (the most common type of diabetes). These studies showed that the negative impact of T2D on health is higher among women compared to men. However, whether this phenomenon holds
Li, Rena; Singh, Meharvan
Studies have shown differences in specific cognitive ability domains and risk of Alzheimer's disease between the men and women at later age. However it is important to know that sex differences in cognitive function during adulthood may have their basis in both organizational effects, i.e., occurring as early as during the neuronal development period, as well as in activational effects, where the influence of the sex steroids influence brain function in adulthood. Further, the rate of cognitive decline with aging is also different between the sexes. Understanding the biology of sex differences in cognitive function will not only provide insight into Alzheimer's disease prevention, but also is integral to the development of personalized, gender-specific medicine. This review draws on epidemiological, translational, clinical, and basic science studies to assess the impact of sex differences in cognitive function from young to old, and examines the effects of sex hormone treatments on Alzheimer's disease in men and women. Copyright © 2014 Elsevier Inc. All rights reserved.
Full Text Available Why the autosomal recombination rate differs between female and male meiosis in most species has been a genetic enigma since the early study of meiosis. Some hypotheses have been put forward to explain this widespread phenomenon and, up to now, only one fact has emerged clearly: In species in which meiosis is achiasmate in one sex, it is the heterogametic one. This pattern, known as the Haldane-Huxley rule, is thought to be a side effect, on autosomes, of the suppression of recombination between the sex chromosomes. However, this rule does not hold for heterochiasmate species (i.e., species in which recombination is present in both sexes but varies quantitatively between sexes and does not apply to species lacking sex chromosomes, such as hermaphroditic plants. In this paper, we show that in plants, heterochiasmy is due to a male-female difference in gametic selection and is not influenced by the presence of heteromorphic sex chromosomes. This finding provides strong empirical support in favour of a population genetic explanation for the evolution of heterochiasmy and, more broadly, for the evolution of sex and recombination.
Guerrieri, Gioia M; Wakim, Paul G; Keenan, P A; Schenkel, Linda A; Berlin, Kate; Gibson, Carolyn J; Rubinow, David R; Schmidt, Peter J
Despite well-established sex differences in the performance on tests of several cognitive domains (e.g., visuospatial ability), few studies in humans have evaluated if these sex differences are evident both in the presence of circulating sex hormones and during sex steroid hormonal suppression. Sex differences identified in the relative absence of circulating levels of estradiol and testosterone suggest that differences in brain structure or function exist independent of current hormonal environment and are more likely a reflection of differing developmental exposures and/or genetic substrates. To evaluate cognitive performance in healthy eugonadal men and women before and again during GnRH agonist-induced hypogonadism. Men (n=16) and women (n=15) without medical or psychiatric illness were matched for IQ. Cognitive tests were performed at baseline (when eugonadal) and after 6-8 weeks of GnRH agonist-induced gonadal suppression. The test batteries included measures of verbal and spatial memory, spatial ability, verbal fluency, motor speed/dexterity, and attention/concentration. Data were analyzed using repeated-measures models. During both eugonadism and hypogonadism, men performed significantly better than women on several measures of visuospatial performance including mental rotation, line orientation, Money Road Map, Porteus maze, and complex figure drawing. Although some test performances showed an effect of hormone treatment, the majority of these differences reflected an improved performance during hypogonadism compared with baseline (and probably reflected practice effects). The well-documented male advantage in visuospatial performance, which we observed during eugonadal conditions, was maintained in the context of short-term suppression of gonadal function in both men and women. These findings suggest that, in humans, sex differences in visuospatial performance are not merely dependent on differences in the current circulating sex steroid environment. Thus
Fritzsche, Karoline; Arnqvis, Göran
Classic sex role theory predicts that sexual selection should be stronger in males in taxa showing conventional sex roles and stronger in females in role reversed mating systems. To test this very central prediction and to assess the utility of different measures of sexual selection, we estimated sexual selection in both sexes in four seed beetle species with divergent sex roles using a novel experimental design. We found that sexual selection was sizeable in females and the strength of sexual selection was similar in females and males in role-reversed species. Sexual selection was overall significantly stronger in males than in females and residual selection formed a substantial component of net selection in both sexes. Furthermore, sexual selection in females was stronger in role-reversed species compared to species with conventional sex roles. Variance-based measures of sexual selection (the Bateman gradient and selection opportunities) were better predictors of sexual dimorphism in reproductive behavior and morphology across species compared to trait-based measures (selection differentials). Our results highlight the importance of using assays that incorporate components of fitness manifested after mating. We suggest that the Bateman gradient is generally the most informative measure of the strength of sexual selection in comparisons across sexes and/or species. © 2013 The Author(s). Evolution © 2013 The Society for the Study of Evolution.
Browne, K D; Hines, Morag; Tully, Ruth J
Within the literature on sex offending, much attention is paid to the distinction between those sex offenders who offend against adults and those who offend against children. In contrast, there is a paucity of research into sex offenders who offend specifically against elderly or older victims. A detailed interview and psychometric tests were conducted with a sample of 28 sex offenders who had been convicted of a sexually motivated offence against an older female. These data were compared to a sample of 23 child sex offenders. Results indicate that amongst other significant differences between these sub-groups, men who offend against older women are generally younger, are more violent, and are more likely to use a weapon and cause injury and death compared to child sex offenders. The men who offended against children were more likely to think about and plan their offending, spend more time with the victim pre and post offence, admit sexual arousal during the offence, and admit to a sexual motivation for the offence. This study suggests that men who sexually offend against older women and men who sexually offend against children are distinct groups. Treatment and risk management strategies should take this into account. Further exploration of this sub-group of offenders is recommended to help inform treatment and risk management strategies for sex offenders who offend against older people.
Luine, Victoria; Gomez, Juan; Beck, Kevin; Bowman, Rachel
Chronic stress causes deleterious changes in physiological function in systems ranging from neural cells in culture to laboratory rodents, sub-human primates and humans. It is notable, however, that the vast majority of research in this area has been conducted in males. In this review, we provide information about chronic stress effects on cognition in female rodents and contrast it with responses in male rodents. In general, females show cognitive resilience to chronic stressors which impair male cognitive function using spatial tasks including the radial arm maze, radial arm water maze, Morris water maze, Y-maze and object placement. Moreover, stress often enhances female performance in some of these cognitive tasks. Memory in females is not affected by stress in non-spatial memory tasks like recognition memory and temporal order recognition memory while males show impaired memory following stress. We discuss possible bases for these sex-dependent differences including the use of different strategies by the sexes to solve cognitive tasks. Whether the sex differences result from changes in non-mnemonic factors is also considered. Sex-dependent differences in alcohol and drug influences on stress responses are also described. Finally, the role of neurally derived estradiol in driving sex differences and providing resilience to stress in females is shown. The importance of determining the nature and extent of sex differences in stress responses is that such differences may provide vital information for understanding why some stress related diseases have different incidence rates between the sexes and for developing novel therapeutic treatments. Copyright © 2016 Elsevier Inc. All rights reserved.
McHugh, R Kathryn; Votaw, Victoria R; Sugarman, Dawn E; Greenfield, Shelly F
The gender gap in substance use disorders (SUDs), characterized by greater prevalence in men, is narrowing, highlighting the importance of understanding sex and gender differences in SUD etiology and maintenance. In this critical review, we provide an overview of sex/gender differences in the biology, epidemiology and treatment of SUDs. Biological sex differences are evident across an array of systems, including brain structure and function, endocrine function, and metabolic function. Gender (i.e., environmentally and socioculturally defined roles for men and women) also contributes to the initiation and course of substance use and SUDs. Adverse medical, psychiatric, and functional consequences associated with SUDs are often more severe in women. However, men and women do not substantively differ with respect to SUD treatment outcomes. Although several trends are beginning to emerge in the literature, findings on sex and gender differences in SUDs are complicated by the interacting contributions of biological and environmental factors. Future research is needed to further elucidate sex and gender differences, especially focusing on hormonal factors in SUD course and treatment outcomes; research translating findings between animal and human models; and gender differences in understudied populations, such as those with co-occurring psychiatric disorders and gender-specific populations, such as pregnant women. Copyright © 2017 Elsevier Ltd. All rights reserved.
Jamison, Rene; Bishop, Somer L.; Huerta, Marisela; Halladay, Alycia K.
Research studies using existing samples of individuals with autism spectrum disorders have identified differences in symptoms between males and females. Differences are typically reported in school age and adolescence, with similarities in symptom presentation at earlier ages. However, existing studies on sex differences are significantly limited,…
Bale, Tracy L
Maternal stress experience is associated with neurodevelopmental disorders including schizophrenia and autism. Recent studies have examined mechanisms by which changes in the maternal milieu may be transmitted to the developing embryo and potentially translated into programming of the epigenome. Animal models of prenatal stress have identified important sex- and temporal-specific effects on offspring stress responsivity. As dysregulation of stress pathways is a common feature in most neuropsychiatric diseases, molecular and epigenetic analyses at the maternal-embryo interface, especially in the placenta, may provide unique insight into identifying much-needed predictive biomarkers. In addition, as most neurodevelopmental disorders present with a sex bias, examination of sex differences in the inheritance of phenotypic outcomes may pinpoint gene targets and specific windows of vulnerability in neurodevelopment, which have been disrupted. This review discusses the association and possible contributing mechanisms of prenatal stress in programming offspring stress pathway dysregulation and the importance of sex.
Torres, A; Gómez-Gil, E; Vidal, A; Puig, O; Boget, T; Salamero, M
To review scientific evidence on gender differences in cognitive functions and influence of sex hormones on cognitive performance. Systematical search of related studies identified in Medline. Women outperform men on verbal fluency, perceptual speed tasks, fine motor skills, verbal memory and verbal learning. Men outperform women on visuospatial ability, mathematical problem solving and visual memory. No gender differences on attention and working memory are found. Researchers distinguish four methods to investigate hormonal influence on cognitive performance: a) patient with hormonal disorders; b) neuroimaging in individuals during hormone administration; c) in women during different phases of menstrual cycle, and d) in patients receiving hormonal treatment (idiopathic hypogonadotropic hypogonadism, postmenopausal women and transsexuals). The findings mostly suggest an influence of sex hormones on some cognitive functions, but they are not conclusive because of limitations and scarcity of the studies. There are gender differences on cognitive functions. Sex hormones seem to influence cognitive performance.
Backer van Ommeren, Tineke; Koot, Hans M; Scheeren, Anke M; Begeer, Sander
Differences in the social limitations of girls compared to boys on the autism spectrum are still poorly understood. Impaired social-emotional reciprocity is a core diagnostic criterion for an autism spectrum disorder. This study compares sex differences in reciprocal behaviour in children with autism spectrum disorder (32 girls, 114 boys) and in typically developing children (24 girls, 55 boys). While children with autism spectrum disorder showed clear limitations in reciprocal behaviour compared to typically developing children, sex differences were found only in the autism spectrum disorder group: girls with autism spectrum disorder had higher reciprocity scores than boys with autism spectrum disorder. However, compared to typically developing girls, girls with autism spectrum disorder showed subtle differences in reciprocal behaviour. The sex-specific response patterns in autism spectrum disorder can inform and improve the diagnostic assessment of autism in females.
Nowadays, the word sex and its related terms (sexual differences, sexual roles and stereotypes), so common not long ago, seems to have been replaced by gender and its related terms (gender differences, gender roles and stereotypes). We can sometimes find both sex and gender sharing the same space in scientific articles, although referring to different domains. In this paper, I try to explain the need for a model that can integrate both of these complex domains of sex and gender, leading to two independent, although complementary, disciplines: Sexology and Genderology. In both cases, I start from a functional standpoint, which will give meaning to both disciplines' specificities, as it is meant to link contributions from different fields of knowledge. This approach can have consequences for research, education, the experience of women, men, and ambiguous individuals, and therapy.
Amani El-Alayli; Erin Kent
Despite its connection with relationship satisfaction, research on physical affection is scarce and fails to disentangle private and public displays of affection. It is important to examine both types if marginalized couples are less comfortable displaying affection publicly. The present study examined whether same-sex couples display less public (but not private) physical affection than different-sex couples due to stronger feelings of relationship marginalization. It also examined how publ...
Halpern, Diane F.; Benbow, Camilla P.; Geary, David C.; Gur, Ruben C.; Hyde, Janet Shibley; Gernsbacher, Morton Ann
Summary Amid ongoing public speculation about the reasons for sex differences in careers in science and mathematics, we present a consensus statement that is based on the best available scientific evidence. Sex differences in science and math achievement and ability are smaller for the mid-range of the abilities distribution than they are for those with the highest levels of achievement and ability. Males are more variable on most measures of quantitative and visuospatial ability, which necessarily results in more males at both high- and low-ability extremes; the reasons why males are often more variable remain elusive. Successful careers in math and science require many types of cognitive abilities. Females tend to excel in verbal abilities, with large differences between females and males found when assessments include writing samples. High-level achievement in science and math requires the ability to communicate effectively and comprehend abstract ideas, so the female advantage in writing should be helpful in all academic domains. Males outperform females on most measures of visuospatial abilities, which have been implicated as contributing to sex differences on standardized exams in mathematics and science. An evolutionary account of sex differences in mathematics and science supports the conclusion that, although sex differences in math and science performance have not directly evolved, they could be indirectly related to differences in interests and specific brain and cognitive systems. We review the brain basis for sex differences in science and mathematics, describe consistent effects, and identify numerous possible correlates. Experience alters brain structures and functioning, so causal statements about brain differences and success in math and science are circular. A wide range of sociocultural forces contribute to sex differences in mathematics and science achievement and ability—including the effects of family, neighborhood, peer, and school
Full Text Available Despite its connection with relationship satisfaction, research on physical affection is scarce and fails to disentangle private and public displays of affection. It is important to examine both types if marginalized couples are less comfortable displaying affection publicly. The present study examined whether same-sex couples display less public (but not private physical affection than different-sex couples due to stronger feelings of relationship marginalization. It also examined how public/private affection and marginalization relate to relationship satisfaction. Women in committed same-sex and different-sex relationships completed surveys of public affection, private affection, marginalization, and relationship satisfaction online. As predicted, women in same-sex relationships displayed less public affection than those in different-sex relationships, an effect mediated by general societal marginalization. Both private and public affection predicted higher relationship satisfaction, whereas feelings of marginalization by friends/family predicted lower relationship satisfaction. We discuss implications for relationship counseling and propose new ways of looking at marginalization.
Proverbio, Alice Mado
Several studies have demonstrated that women show a greater interest for social information and empathic attitude than men. This article reviews studies on sex differences in the brain, with particular reference to how males and females process faces and facial expressions, social interactions, pain of others, infant faces, faces in things (pareidolia phenomenon), opposite-sex faces, humans vs. landscapes, incongruent behavior, motor actions, biological motion, erotic pictures, and emotional information. Sex differences in oxytocin-based attachment response and emotional memory are also mentioned. In addition, we investigated how 400 different human faces were evaluated for arousal and valence dimensions by a group of healthy male and female University students. Stimuli were carefully balanced for sensory and perceptual characteristics, age, facial expression, and sex. As a whole, women judged all human faces as more positive and more arousing than men. Furthermore, they showed a preference for the faces of children and the elderly in the arousal evaluation. Regardless of face aesthetics, age, or facial expression, women rated human faces higher than men. The preference for opposite- vs. same-sex faces strongly interacted with facial age. Overall, both women and men exhibited differences in facial processing that could be interpreted in the light of evolutionary psychobiology. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Bangasser, Debra A; Eck, Samantha R; Telenson, Alexander M; Salvatore, Madeleine
There are sex differences in the prevalence and presentation of many psychiatric disorders. For example, posttraumatic stress disorder (PTSD) and major depression are more common in women than men, and women with these disorders present with more hyperarousal symptoms than men. In contrast, attention deficit hyperactivity disorder (ADHD) and schizophrenia are more common in men than women, and men with these disorders have increased cognitive deficits compared to women. A shared feature of the aforementioned psychiatric disorders is the contribution of stressful events to their onset and/or severity. Here we propose that sex differences in stress responses bias females towards hyperarousal and males towards cognitive deficits. Evidence from clinical and preclinical studies is detailed. We also describe underlying neurobiological mechanisms. For example, sex differences in stress receptor signaling and trafficking in the locus coeruleus-arousal center are detailed. In learning circuits, evidence for sex differences in dendritic morphology is provided. Finally, we describe how evaluating sex-specific mechanisms for responding to stress in female and male rodents can lead to better treatments for stress-related psychiatric disorders. Copyright © 2017 Elsevier Inc. All rights reserved.
Grattan, D.R.; Liu, L.; Bunn, S.J.
Full text: Sex differences in the brain may arise from the organisational effects of exposure to sex steroids during development, or from the exposure to a differential hormonal milieu in the adult. There is a marked sex difference in the neuroendocrine mechanism that regulates prolactin secretion. Levels of prolactin in the blood are higher in females than in males. Similarly, basal activity of tuberoinfundibular dopamine (TIDA) neurons, which are involved in the tonic suppression of prolactin secretion, are two fold higher in females than in males. Prolactin is known to stimulate the activity of TIDA neurons, thereby regulating its own secretion by short-loop feedback. Hence, it is thought that elevated TIDA neuronal activity in females is induced by increased prolactin in the blood. We have recently demonstrated that prolactin stimulation of TIDA neurons requires the transcription factor, STAT5b. We have now investigated prolactin secretion in male and female STAT5b-deficient mice, to test the hypothesis that sex differences in TIDA neuronal activity are dependent on stimulation by prolactin acting through STAT5b. Prolactin levels in blood were measured by radioimmunoassay, and TIDA activity was assessed by measuring concentrations of the dopamine metabolite DOPAC in the median eminence by HPLC, and by measuring tyrosine hydroxylase mRNA in the arcuate nucleus by real-time RT-PCR. The data demonstrate marked gender differences in the activity of TIDA neurons. While TIDA activity in STAT5b-deficient mice was reduced compared to wild type, the sex difference persisted. Since STAT5b is required for the actions of prolactin on these neurons, we can conclude that the sexual dimorphism in brain function is independent of gender differences in blood levels of prolactin. It seems likely that differential exposure to gonadal steroid hormones, either during development or in adulthood, might underlie the sex difference in TIDA neuronal activity. Copyright (2001
Backer van Ommeren, Tineke; Koot, Hans M.; Scheeren, Anke M.; Begeer, Sander
Differences in the social limitations of girls compared to boys on the autism spectrum are still poorly understood. Impaired social-emotional reciprocity is a core diagnostic criterion for an autism spectrum disorder. This study compares sex differences in reciprocal behaviour in children with autism spectrum disorder (32 girls, 114 boys) and in…
Catalan, Rosa Maria Jimenez
Reports the results of a descriptive study on sex differences in the use of a second language. A questionnaire was administered to 581 Spanish-speaking students learning Basque and English as second language to answer the following question: Do male and female second language learners differ in the number and the range of vocabulary strategies…
This study explored sex differences in mathematics performance of students in the final year of high school and changes in these differences over a 3-year period in Ghana. A convenience sample of 182 students, 109 boys and 72 girls in three high schools in Ghana was used. Mathematics performance was assessed using ...
Backer van Ommeren, Tineke; Koot, Hans M; Scheeren, Anke M; Begeer, Sander
Differences in the social limitations of girls compared to boys on the autism spectrum are still poorly understood. Impaired social-emotional reciprocity is a core diagnostic criterion for an autism spectrum disorder. This study compares sex differences in reciprocal behaviour in children with
Mills, Rosemary S. L.; And Others
Examines sex differences among 70 adults in the resolution of prosocial dilemmas involving self-sacrifice. Findings suggest that even when women and men make the same choices, they seem to think about and experience their choices in different ways. (MW)
Brenner, O. C.; Tomkiewicz, Joseph
Sex differences in job orientation found by Manhardt (1972) were explored to determine if they still exist, or if a trend toward similarity as found in studies on traits and behaviors prevails. Implications for personnel managers in handling differences on job orientation of males and females are discussed. (Author/KC)
Aanerud, Joel; Borghammer, Per; Rodell, Anders; Jónsdottir, Kristjana Y; Gjedde, Albert
Brain energy metabolism is held to reflect energy demanding processes in neuropil related to the density and activity of synapses. There is recent evidence that men have higher density of synapses in temporal cortex than women. One consequence of these differences would be different rates of cortical energy turnover and blood flow in men and women. To test the hypotheses that rates of oxygen consumption (CMRO 2 ) and cerebral blood flow are higher in men than in women in regions of cerebral cortex, and that the differences persist with aging, we used positron emission tomography to determine cerebral blood flow and cerebral metabolic rate of oxygen as functions of age in healthy volunteers of both sexes. Cerebral metabolic rate of oxygen did not change with age for either sex and there were no differences of mean values of cerebral metabolic rate of oxygen between men and women in cerebral cortex. Women had significant decreases of cerebral blood flow as function of age in frontal and parietal lobes. Young women had significantly higher cerebral blood flow than men in frontal and temporal lobes, but these differences had disappeared at age 65. The absent sex difference of cerebral energy turnover suggests that the known differences of synaptic density between the sexes are counteracted by opposite differences of individual synaptic activity.
David C. Geary
Full Text Available Darwin’s (1871 theory of sexual selection and the associated mechanisms of intrasexual competition (e.g., male-male competition and intersexual choice (e.g., female choice of mates have guided the scientific study of sex differences in hundreds of non-human species. These mechanisms and several recent advances in our understanding of the evolution and expression of sex differences in non-human species are described. The usefulness of this theory for approaching the study human sex differences is illustrated with discussion of patterns of women’s mate preferences and choices and with discussion of men’s one-on-one and coalitional competition. A comparison of these aspects of intersexual choice and intrasexual competition in humans and non-human species is provided, as is discussion of cultural variation in the expression of these behaviors. cultural influences (Maccoby & Jacklin, 1974.
Even J. Lanseng
Full Text Available This research investigates differences in men’s and women’s attitudes toward ads featuring product-relevant sex appeals. It is found that women, but not men, were more negative toward an ad featuring an attractive opposite-sex model when their commitment thoughts were heightened. Women were also more negative toward an ad with an attractive same-sex model in the presence of commitment thoughts, but only when they scored high on sociosexuality. Men appeared unaffected, regardless of their level of sociosexuality. Commitment thoughts were manipulated by two types of prime, a parenting prime (study1 and a romantic prime (study 2.Results are explained by differences in how men and women react to sexual material and by differences in men’s and women’s evolved mating preferences.
Lanseng, Even J
This research investigates differences in men's and women's attitudes toward ads featuring product-relevant sex appeals. It is found that women, but not men, were more negative toward an ad featuring an attractive opposite-sex model when their commitment thoughts were heightened. Women were also more negative toward an ad with an attractive same-sex model in the presence of commitment thoughts, but only when they scored high on sociosexuality. Men appeared unaffected, regardless of their level of sociosexuality. Commitment thoughts were manipulated by two types of prime, a parenting prime (study1) and a romantic prime (study 2). Results are explained by differences in how men and women react to sexual material and by differences in men's and women's evolved mating preferences.
Oksuzyan, A; Shkolnikova, M; Vaupel, J W
and a male advantage in self-rated health, physical functioning, and depression symptomatology. Only on cognitive tests males performed similarly to or worse than women. Nevertheless, Muscovite males had more than twice higher mortality at ages 55-69 years compared to Muscovite women, almost double the ratio......In high income countries females outlive men, although they generally report worse health, the so-called male-female health-survival paradox. Russia has one of the world's largest sex difference in life expectancy with a male disadvantage of more than 10 years. We compare components of the paradox...... between Denmark and Moscow by examining sex differences in mortality and several health measures. The Human Mortality Database and the Russian Fertility and Mortality Database were used to examine sex differences in all-cause death rates in Denmark, Russia, and Moscow in 2007-2008. Self-reported health...
Sex differences in the morphology of neural and peripheral structures related to reproduction often parallel the frequency of particular behaviours displayed by males and females. In a variety of model organisms, these sex differences are organized in development by gonadal steroids, which also act in adulthood to modulate behavioural expression and in some cases to generate parallel anatomical changes on a seasonal basis. Data collected from diverse species, however, suggest that changes in hormone availability are not sufficient to explain sex and seasonal differences in structure and function. This paper pulls together some of this literature from songbirds and lizards and considers the information in the broader context of taking a comparative approach to investigating genetic mechanisms associated with behavioural neuroendocrinology. PMID:26833833
McCullough Louise D
Full Text Available Abstract We have known for some time that the epidemiology of human stroke is sexually dimorphic until late in life, well beyond the years of reproductive senescence and menopause. Now, a new concept is emerging: the mechanisms and outcome of cerebral ischemic injury are influenced strongly by biological sex as well as the availability of sex steroids to the brain. The principal mammalian estrogen (17 β estradiol or E2 is neuroprotective in many types of brain injury and has been the major focus of investigation over the past several decades. However, it is becoming increasingly clear that although hormones are a major contributor to sex-specific outcomes, they do not fully account for sex-specific responses to cerebral ischemia. The purpose of this review is to highlight recent studies in cell culture and animal models that suggest that genetic sex determines experimental stroke outcome and that divergent cell death pathways are activated after an ischemic insult. These sex differences need to be identified if we are to develop efficacious neuroprotective agents for use in stroke patients.
Nedeltchev, Krassen; Wiedmer, Sebastian; Schwerzmann, Markus; Windecker, Stephan; Haefeli, Tobias; Meier, Bernhard; Mattle, Heinrich P; Arnold, Marcel
Sex differences in patients with patent foramen ovale (PFO) and cryptogenic stroke have not been systematically analyzed. We aimed to determine sex influences on demographics, vascular risk factors, clinical manifestations, stroke location, and clinical outcome. One thousand two hundred eighty-eight consecutive patients with ischemic stroke or transient ischemic attack (TIA) were admitted to a single stroke center. All patients underwent a complete stroke workup including clinical examination, standard blood tests, cerebral and vascular imaging, transesophageal echocardiography, and 24-hour electrocardiography. In 500 patients, no definite etiology could be established (cryptogenic stroke/TIA). Of them, 167 patients (107 men and 60 women, mean age 52 +/- 13 years) had an PFO. The prevalence of PFO in patients with cryptogenic stroke or TIA was higher in men than in women (38% vs 28%, P = .014). Stroke severity and the prevalence of risk factors did not differ between the 2 sexes. There was an independent association between male sex and stroke location in the posterior cerebral circulation (OR 3.0, 95% CI 1.4-6.5, P = .006). Men and women did not differ in respect to PFO grade, prevalence of right-to-left shunt at rest, or coexistence of atrial septal aneurysm. Clinical outcome at 3 months was similar in both sexes. Patent foramen ovale was more prevalent in men than in women with cryptogenic stroke. There were no sex influences on age, risk factors, echocardiographic characteristics of PFO, or clinical outcome. Male sex was independently associated with stroke in the posterior cerebral circulation.
Cross, Catharine P; Brown, Gillian R; Morgan, Thomas J H; Laland, Kevin N
Lack of confidence in one's own ability can increase the likelihood of relying on social information. Sex differences in confidence have been extensively investigated in cognitive tasks, but implications for conformity have not been directly tested. Here, we tested the hypothesis that, in a task that shows sex differences in confidence, an indirect effect of sex on social information use will also be evident. Participants (N = 168) were administered a mental rotation (MR) task or a letter transformation (LT) task. After providing an answer, participants reported their confidence before seeing the responses of demonstrators and being allowed to change their initial answer. In the MR, but not the LT, task, women showed lower levels of confidence than men, and confidence mediated an indirect effect of sex on the likelihood of switching answers. These results provide novel, experimental evidence that confidence is a general explanatory mechanism underpinning susceptibility to social influences. Our results have implications for the interpretation of the wider literature on sex differences in conformity. © 2016 The British Psychological Society.
Merz, Christian J; Wolf, Oliver T
Stress influences emotional learning and memory processes. These effects are thought to underlie stress-associated mental disorders. Sex differences in stress reactivity and in central nervous system stress sensitivity illustrate the important modulatory role of sex hormones. This Review outlines how stress hormones influence different stages of the fear conditioning process, such as fear acquisition, extinction, and retrieval. Results will be compared with findings on the impact of stress on episodic memory. The focus is on the available human data on sex differences and the impact sex hormones have on the stress effects on emotional learning and memory. It will become apparent that the menstrual cycle but also the intake of hormonal contraceptives modulates the impact of stress on brain and behavior. Additional basic research is needed for a deeper insight regarding the interplay between stress and sex hormones in emotion and cognition. In addition, new treatment options might be derived to optimize existing strategies such as exposure therapy, which relies on the principles of fear conditioning. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Ruytjens, Liesbet; Georgiadis, Janniko R.; Holstege, Gert; Wit, Hero P.; Albers, Frans W.J.; Willemsen, Antoon T.M.
We used PET to study cortical activation during auditory stimulation and found sex differences in the human primary auditory cortex (PAC). Regional cerebral blood flow (rCBF) was measured in 10 male and 10 female volunteers while listening to sounds (music or white noise) and during a baseline (no auditory stimulation). We found a sex difference in activation of the left and right PAC when comparing music to noise. The PAC was more activated by music than by noise in both men and women. But this difference between the two stimuli was significantly higher in men than in women. To investigate whether this difference could be attributed to either music or noise, we compared both stimuli with the baseline and revealed that noise gave a significantly higher activation in the female PAC than in the male PAC. Moreover, the male group showed a deactivation in the right prefrontal cortex when comparing noise to the baseline, which was not present in the female group. Interestingly, the auditory and prefrontal regions are anatomically and functionally linked and the prefrontal cortex is known to be engaged in auditory tasks that involve sustained or selective auditory attention. Thus we hypothesize that differences in attention result in a different deactivation of the right prefrontal cortex, which in turn modulates the activation of the PAC and thus explains the sex differences found in the activation of the PAC. Our results suggest that sex is an important factor in auditory brain studies. (orig.)
Mielke, Michelle M; Vemuri, Prashanthi; Rocca, Walter A
With the aging of the population, the burden of Alzheimer's disease (AD) is rapidly expanding. More than 5 million people in the US alone are affected with AD and this number is expected to triple by 2050. While men may have a higher risk of mild cognitive impairment (MCI), an intermediate stage between normal aging and dementia, women are disproportionally affected with AD. One explanation is that men may die of competing causes of death earlier in life, so that only the most resilient men may survive to older ages. However, many other factors should also be considered to explain the sex differences. In this review, we discuss the differences observed in men versus women in the incidence and prevalence of MCI and AD, in the structure and function of the brain, and in the sex-specific and gender-specific risk and protective factors for AD. In medical research, sex refers to biological differences such as chromosomal differences (eg, XX versus XY chromosomes), gonadal differences, or hormonal differences. In contrast, gender refers to psychosocial and cultural differences between men and women (eg, access to education and occupation). Both factors play an important role in the development and progression of diseases, including AD. Understanding both sex- and gender-specific risk and protective factors for AD is critical for developing individualized interventions for the prevention and treatment of AD.
Ruytjens, Liesbet [University Medical Center Groningen, Department of Otorhinolaryngology, Groningen (Netherlands); University Medical Center Utrecht, Department Otorhinolaryngology, P.O. Box 85500, Utrecht (Netherlands); Georgiadis, Janniko R. [University of Groningen, University Medical Center Groningen, Department of Anatomy and Embryology, Groningen (Netherlands); Holstege, Gert [University of Groningen, University Medical Center Groningen, Center for Uroneurology, Groningen (Netherlands); Wit, Hero P. [University Medical Center Groningen, Department of Otorhinolaryngology, Groningen (Netherlands); Albers, Frans W.J. [University Medical Center Utrecht, Department Otorhinolaryngology, P.O. Box 85500, Utrecht (Netherlands); Willemsen, Antoon T.M. [University Medical Center Groningen, Department of Nuclear Medicine and Molecular Imaging, Groningen (Netherlands)
We used PET to study cortical activation during auditory stimulation and found sex differences in the human primary auditory cortex (PAC). Regional cerebral blood flow (rCBF) was measured in 10 male and 10 female volunteers while listening to sounds (music or white noise) and during a baseline (no auditory stimulation). We found a sex difference in activation of the left and right PAC when comparing music to noise. The PAC was more activated by music than by noise in both men and women. But this difference between the two stimuli was significantly higher in men than in women. To investigate whether this difference could be attributed to either music or noise, we compared both stimuli with the baseline and revealed that noise gave a significantly higher activation in the female PAC than in the male PAC. Moreover, the male group showed a deactivation in the right prefrontal cortex when comparing noise to the baseline, which was not present in the female group. Interestingly, the auditory and prefrontal regions are anatomically and functionally linked and the prefrontal cortex is known to be engaged in auditory tasks that involve sustained or selective auditory attention. Thus we hypothesize that differences in attention result in a different deactivation of the right prefrontal cortex, which in turn modulates the activation of the PAC and thus explains the sex differences found in the activation of the PAC. Our results suggest that sex is an important factor in auditory brain studies. (orig.)
Full Text Available As per sample of 212 examinees at the age of 11 (±6 months at the fifth grade in Montenegrin elementary schools, it was used the system of 12 variables for the estimation of anthropometrical characteristis. The purpose of the examination was to establish differentiations between different students sex in the initial and final measuring. As for results given by using discriminant analysis and univariant analysis of variance on the anthropometrical student's status, it can be concluded that there's a statistical significant level in discrimination of subsamples of different sex.
Stinson, Crystal; Deng, Mohong; Yee, Michael B; Bellinger, Larry L; Kinchington, Paul R; Kramer, Phillip R
Most people are initially infected with varicella zoster virus (VZV) at a young age and this infection results in chickenpox. VZV then becomes latent and reactivates later in life resulting in herpes zoster (HZ) or "shingles". Often VZV infects neurons of the trigeminal ganglia to cause ocular problems, orofacial disease and occasionally a chronic pain condition termed post-herpetic neuralgia (PHN). To date, no model has been developed to study orofacial pain related to varicella zoster. Importantly, the incidence of zoster associated pain and PHN is known to be higher in women, although reasons for this sex difference remain unclear. Prior to this work, no animal model was available to study these sex-differences. Our goal was to develop an orofacial animal model for zoster associated pain which could be utilized to study the mechanisms contributing to this sex difference. To develop this model VZV was injected into the whisker pad of rats resulting in IE62 protein expression in the trigeminal ganglia; IE62 is an immediate early gene in the VZV replication program. Similar to PHN patients, rats showed retraction of neurites after VZV infection. Treatment of rats with gabapentin, an agent often used to combat PHN, ameliorated the pain response after whisker pad injection. Aversive behavior was significantly greater for up to 7 weeks in VZV injected rats over control inoculated rats. Sex differences were also seen such that ovariectomized and intact female rats given the lower dose of VZV showed a longer affective response than male rats. The phase of the estrous cycle also affected the aversive response suggesting a role for sex steroids in modulating VZV pain. These results suggest that this rat model can be utilized to study the mechanisms of 1) orofacial zoster associated pain and 2) the sex differences underlying zoster associated pain.
Andersen, Nicolas E; Dahmani, Louisa; Konishi, Kyoko; Bohbot, Véronique D
Reports of sex differences in wayfinding have typically used paradigms sensitive to the female advantage (navigation by landmarks) or sensitive to the male advantage (navigation by cardinal directions, Euclidian coordinates, environmental geometry, and absolute distances). The current virtual navigation paradigm allowed both men and women an equal advantage. We studied sex differences by systematically varying the number of landmarks. Eye tracking was used to quantify sex differences in landmark utilisation as participants solved an eight-arm radial maze task within different virtual environments. To solve the task, participants were required to remember the locations of target objects within environments containing 0, 2, 4, 6, or 8 landmarks. We found that, as the number of landmarks available in the environment increases, the proportion of time men and women spend looking at landmarks and the number of landmarks they use to find their way increases. Eye tracking confirmed that women rely more on landmarks to navigate, although landmark fixations were also associated with an increase in task completion time. Sex differences in navigational behaviour occurred only in environments devoid of landmarks and disappeared in environments containing multiple landmarks. Moreover, women showed sustained landmark-oriented gaze, while men's decreased over time. Finally, we found that men and women use spatial and response strategies to the same extent. Together, these results shed new light on the discrepancy in landmark utilisation between men and women and help explain the differences in navigational behaviour previously reported. Copyright © 2011 Elsevier Inc. All rights reserved.
Levy, Kenneth N; Kelly, Kristen M
Studies have found that more men than women endorse sexual infidelity as more distressing than emotional infidelity, whereas more women than men endorse emotional infidelity as more distressing than sexual infidelity. Some evolutionary psychologists have proposed that this sex difference can be best conceptualized as reflecting evolution-based differences in parental investment that produce a need for paternity certainty among men and a need for male investment in offspring among women. Nonetheless, a conspicuous subset of men report emotional infidelity as more distressing than sexual infidelity. Current theorizing explains between-sex differences but not within-sex differences. We hypothesized that attachment-style differences may help to explain both between- and within-sex differences in jealousy. As hypothesized, dismissing avoidant participants reported more jealousy regarding sexual than emotional infidelity (64.8%), and secure participants, including secure men, reported more jealousy regarding emotional than sexual infidelity (77.3%), chi(2)(3, N = 411) = 45.03, p jealousy relationship by attachment style. Implications of an attachment perspective are discussed.
Bobzean, Samara A M; DeNobrega, Aliza K; Perrotti, Linda I
Epidemiological data demonstrate that while women report lower rates of drug use than men, the number of current drug users and abusers who are women continues to increase. In addition women progress through the phases of addiction differently than men; women transition from casual drug use to addiction faster, are more reactive to stimuli that trigger relapse, and have higher rates of relapse then men. Sex differences in physiological and psychological responses to drugs of abuse are well documented and it is well established that estrogen effects on dopamine (DA) systems are largely responsible for these sex differences. However, the downstream mechanisms that result from interactions between estrogen and the effects of drugs of abuse on the DA system are just beginning to be explored. Here we review the basic neurocircuitry which underlies reward and addiction; highlighting the neuroadaptive changes that occur in the mesolimbic dopamine reward and anti-reward/stress pathways. We propose that sex differences in addiction are due to sex differences in the neural systems which mediate positive and negative reinforcement and that these differences are modulated by ovarian hormones. This forms a neurobehavioral basis for the search for the molecular and cellular underpinnings that uniquely guide motivational behaviors and make women more vulnerable to developing and sustaining addiction than men. Copyright © 2014 Elsevier Inc. All rights reserved.
Neuhaus, Andres H; Opgen-Rhein, Carolin; Urbanek, Carsten; Gross, Melanie; Hahn, Eric; Ta, Thi Minh Tam; Koehler, Simone; Dettling, Michael
Functional neuroimaging studies have increasingly aimed at approximating neural substrates of human cognitive sex differences elicited by visuospatial challenge. It has been suggested that females and males use different behaviorally relevant neurocognitive strategies. In females, greater right prefrontal cortex activation has been found in several studies. The spatiotemporal dynamics of neural events associated with these sex differences is still unclear. We studied 22 female and 22 male participants matched for age, education, and nicotine with 29-channel-electroencephalogram recorded under a visual selective attention paradigm, the Attention Network Test. Visual event-related potentials (ERP) were topographically analyzed and neuroelectric sources were estimated. In absence of behavioral differences, ERP analysis revealed a novel frontal-occipital second peak of visual N100 that was significantly increased in females relative to males. Further, in females exclusively, a corresponding central ERP component at around 220 ms was found; here, a strong correlation between stimulus salience and sex difference of the central ERP component amplitude was observed. Subsequent source analysis revealed increased cortical current densities in right rostral prefrontal (BA 10) and occipital cortex (BA 19) in female subjects. This is the first study to report on a tripartite association between sex differences in ERPs, visual stimulus salience, and right prefrontal cortex activation during attentional processing. 2009 Wiley-Liss, Inc.
Full Text Available Root system size is a key trait for improving water and nitrogen uptake efficiency in wheat (Triticum aestivum L.. This study aimed (i to characterize the root system and shoot traits of five wheat cultivars with apparent differences in root system size; (ii to evaluate whether the apparent differences in root system size observed at early vegetative stages in a previous semi-hydroponic phenotyping experiment are reflected at later phenological stages in plants grown in soil using large rhizoboxes. The five wheat cultivars were grown in a glasshouse in rhizoboxes filled to 1.0 m with field soil. Phenology and shoot traits were measured and root growth and proliferation were mapped to quantify root length density (RLD, root length per plant, root biomass and specific root length (SRL. Wheat cultivars with large root systems had greater root length, more root biomass and thicker roots, particularly in the top 40 cm, than those with small root systems. Cultivars that reached anthesis later had larger root system sizes than those that reached anthesis earlier. Later anthesis allowed more time for root growth and proliferation. Cultivars with large root systems had 25% more leaf area and biomass than those with small root systems, which presumably reflects high canopy photosynthesis to supply the demand for carbon assimilates to roots. Wheat cultivars with contrasting root system sizes at the onset of tillering (Z2.1 in a semi-hydroponic phenotyping system maintained their size ranking at booting (Z4.5 when grown in soil. Phenology, particularly time to anthesis, was associated with root system size.
Full Text Available Maize foundation parents (FPs play no-alternative roles in hybrid breeding because they were widely used in the development of new lines and hybrids. The combination of different identity-by-descent (IBD segments and genes could account for the formation patterns of different FPs, and knowledge of these IBD regions would provide an extensive foundation for the development of new candidate FP lines in future maize breeding. In this paper, a panel of 304 elite lines derived from FPs, i.e., B73, 207, Mo17, and Huangzaosi (HZS, was collected and analyzed using 43,252 single nucleotide polymorphism (SNP markers. Most IBD segments specific to particular FP groups were identified, including 116 IBD segments in B73, 105 in Mo17, 111 in 207, and 190 in HZS. In these regions, 423 quantitative trait nucleotides (QTNs associated with 15 agronomic traits and 804 candidate genes were identified. Some known adaptation-related genes, e.g., dwarf8 and vgt1 in HZS, zcn8 and epc in Mo17, and ZmCCT in 207, were validated as being tightly linked to particular IBD segments. In addition, numerous new candidate genes were also identified. For example, GRMZM2G154278 in HZS, which belongs to the cell cycle control family, was closely linked to a QTN of the ear height/plant height (EH/PH trait; GRMZM2G051943 in 207, which encodes an endochitinase precursor (EP chitinase, was closely linked to a QTN for kernel density; and GRMZM2G170586 in Mo17 was closely linked to a QTN for ear diameter. Complex correlations among these genes were also found. Many IBD segments and genes were included in the formation of FP lines, and complex regulatory networks exist among them. These results provide new insights on the genetic basis of complex traits and provide new candidate IBD regions or genes for the improvement of special traits in maize production.
Shaw, Allison K; Kokko, Hanna; Neubert, Michael G
The rate at which a population grows and spreads can depend on individual behaviour and interactions with others. In many species with two sexes, males and females differ in key life-history traits (e.g. growth, survival and dispersal), which can scale up to affect population rates of growth and spread. In sexually reproducing species, the mechanics of locating mates and reproducing successfully introduce further complications for predicting the invasion speed (spread rate), as both can change nonlinearly with density. Most models of population spread are based on one sex, or include limited aspects of sex differences. Here we ask whether and how the dynamics of finding mates interact with sex-specific life-history traits to influence the rate of population spread. We present a hybrid approach for modelling invasions of populations with two sexes that links individual-level mating behaviour (in an individual-based model) to population-level dynamics (in an integrodifference equation model). We find that limiting the amount of time during which individuals can search for mates causes a demographic Allee effect which can slow, delay, or even prevent an invasion. Furthermore, any sex-based asymmetries in life history or behaviour (skewed sex ratio, sex-biased dispersal, and sex-specific mating behaviours) amplify these effects. In contrast, allowing individuals to mate more than once ameliorates these effects, enabling polygynandrous populations to invade under conditions where monogamously mating populations would fail to establish. We show that details of individuals' mating behaviour can impact the rate of population spread. Based on our results, we propose a stricter definition of a mate-finding Allee effect, which is not met by the commonly used minimum mating function. Our modelling approach, which links individual- and population-level dynamics in a single model, may be useful for exploring other aspects of individual behaviour that are thought to impact the
van Hemmen, J; Saris, I M J; Cohen-Kettenis, P T; Veltman, D J; Pouwels, P J W; Bakker, J
Sex differences have been described regarding several aspects of human brain morphology; however, the exact biological mechanisms underlying these differences remain unclear in humans. Women with the complete androgen insensitivity syndrome (CAIS), who lack androgen action in the presence of a 46,XY
Broidy, Lisa; Cauffman, Elizabeth; Espelage, Dorothy L; Mazerolle, Paul; Piquero, Alex
Implicit in most theoretical accounts of sex differences in offending is the assumption that females are less likely than males to engage in crime--especially serious, violent crime--in part because of their comparatively higher levels of concern for others and stronger affiliative ties. Much research suggests that significant sex differences in both empathy and serious offending emerge in adolescence, with females displaying notably higher levels of empathy and males engaging in notably higher levels of serious offending. However, there has been little empirical work assessing the degree to which sex differences in empathy among adolescents can account for sex differences in offending. This research uses data from a sample of adolescents attending public high schools in Philadelphia (n = 425) and a sample of adolescents incarcerated in the California Youth Authority (CYA) (n = 232) to examine the relation between empathy and serious offending. Results suggest that empathy acts as a protective factor for both males and females but that there are subtle differences among males and females in the relation between empathy and offending.
Lapidus, Alla; Goltsman, Eugene; Auger, Sandrine; Galleron,Nathalie; Segurens, Beatrice; Dossat, Carole; Land, Miriam L.; Broussole,Veronique; Brillard, Julien; Guinebretiere, Marie-Helene; Sanchis,Vincent; Nguen-the, Christophe; Lereclus, Didier; Richardson, Paul; Winker, Patrick; Weissenbach, Jean; Ehrlich, S.Dusko; Sorokin, Alexei
The cereus group represents sporulating soil bacteriacontaining pathogenic strains which may cause diarrheic or emetic foodpoisoning outbreaks. Multiple locus sequence typing revealed a presencein natural samples of these bacteria of about thirty clonal complexes.Application of genomic methods to this group was however biased due tothe major interest for representatives closely related to B. anthracis.Albeit the most important food-borne pathogens were not yet defined,existing dataindicate that they are scattered all over the phylogenetictree. The preliminary analysis of the sequences of three genomesdiscussed in this paper narrows down the gaps in our knowledge of thecereus group. The strain NVH391-98 is a rare but particularly severefood-borne pathogen. Sequencing revealed that the strain must be arepresentative of a novel bacterial species, for which the name Bacilluscytotoxis is proposed. This strain has a reduced genome size compared toother cereus group strains. Genome analysis revealed absence of sigma Bfactor and the presence of genes encoding diarrheic Nhe toxin, notdetected earlier. The strain B. cereus F837/76 represents a clonalcomplex close to that of B. anthracis. Including F837/76, three such B.cereus strains had been sequenced. Alignment of genomes suggests that B.anthracis is their common ancestor. Since such strains often emerge fromclinical cases, they merit a special attention. The third strain, KBAB4,is a typical psychrotrophe characteristic to unbiased soil communities.Phylogenic studies show that in nature it is the most active group interms of gene exchange. Genomic sequence revealed high presence ofextra-chromosomal genetic material (about 530 kb) that may account forthis phenomenon. Genes coding Nhe-like toxin were found on a big plasmidin this strain. This may indicate a potential mechanism of toxicityspread from the psychrotrophic strain community. The results of thisgenomic work and ecological compartments of different strains incite
Yoo, Kyung Don; Yoon, Hyung-Jin; Hwang, Seung-Sik; Heo, Nam Ju; Chin, Ho Jun; Yang, Seung Hee; Joo, Kwon Wook; Kim, Yon Su; Lee, Hajeong
Renal hyperfiltration (RHF) is a marker of early kidney injury that was recently shown to be a novel marker of mortality. However, it has no clear definition. In this study, we suggested an age- and sex-adjusted RHF definition and explored the association between RHF and mortality by sex. We analyzed data from individuals receiving routine health examinations from 1995 to 2009. RHF was defined as an estimated glomerular filtration rate over the 95th percentile matched for age and sex. A total of 114 966 individuals were included. During the 75-month of observation period, 2559 (2.2%) participants died. Among those, 71.4% were men. Because sex and RHF had a significant interaction for mortality (P for interaction sex. RHF was related to lower body weight and a higher proportion of cigarette smoking in men, whereas these relationships were not found in women. In the Kaplan-Meier curve, RHF was associated with higher mortality rate than non-RHF in both sexes, but this relationship was more prominent in men. In the multivariate analysis, RHF remained as an independent risk factor for all-cause mortality even after adjustment for confounding in men (hazard ratio, 1.34; 95% confidence interval, 1.12-1.59; P = 0.001). In women, RHF was not associated with increased mortality. We demonstrated that RHF was a significant risk factor for mortality in men but not in women. The mechanisms and clinical implications of these different associations according to sex require a further clarification. © 2016 Asian Pacific Society of Nephrology.
Swaab, Dick F.; Chung, Wilson C. J.; Kruijver, Frank P. M.; Hofman, Michel A.; Hestiantoro, Andon
Quite a number of structural and functional sex differences have been reported in the human hypothalamus and adjacent structures that may be related to not only reproduction, sexual orientation and gender identity, but also to the often pronounced sex differences in prevalence of psychiatric and
The biological basis for differences between the sexes has become increasingly clear in recent years. The nature-nurture debate has made way for the view that the individual is a product of the interaction between genes and environment. For the world of school leadership this means that instead of
Coffman, M. C.; Anderson, L. C.; Naples, A. J.; McPartland, J. C.
Autism spectrum disorder (ASD) is more common in males than females. An underrepresentation of females in the ASD literature has led to limited knowledge of differences in social function across the sexes. Investigations of face perception represent a promising target for understanding variability in social functioning between males and females.…
Zalta, Alyson K.; Chambless, Dianne L.
A multivariate model was developed to examine the relative contributions of mastery, stress, interpretive bias, and coping to sex differences in worry. Rumination was incorporated as a second outcome variable to test the specificity of these associations. Participants included two samples of undergraduates totaling 302 men and 379 women. A path…
Waals, F.W. van der; Mohrs, J.; Foets, M.
Objective: To analyse sex differences among recipients of benzodiazepines in Dutch general practice. Design-Study of consultations and associated interventions as recorded in the Dutch national survey of general practice. Setting: Practices of 45 general practitioners monitored during 1 April to 30
Yan, Yan; Dominguez, Sky; Fisher, Daniel W; Dong, Hongxin
Clinical studies indicate that Alzheimer's disease (AD) disproportionately affects women in both disease prevalence and severity, but the mechanisms underlying this sex divergence are unknown. Though some have suggested this difference in risk is a reflection of known differences in longevity between men and women, mounting clinical and preclinical evidence supports women also having intrinsic susceptibilities towards the disease. While a number of potential risk factors have been hypothesized to affect these differences in risks, none have been definitively verified. In this review, we discuss a novel hypothesis whereby women's susceptibility to chronic stress also mediates increased risk for AD. As stress is a risk factor for AD, and women are twice as likely to develop mood disorders where stress is a major etiology, it is possible that sex dimorphisms in stress responses contribute to the increase in women with AD. In line with this, sex divergence in biochemical responses to stress have been noted along the hypothalamic-pituitary-adrenal (HPA) axis and among known molecular effectors of AD, with crosstalk between these processes also being likely. In addition, activation of the cortical corticotrophin-releasing factor receptor 1 (CRF1) signaling pathway leads to distinct female-biased increases in molecules associated with AD pathogenesis. Therefore, the different biochemical responses to stress between women and men may represent an intrinsic, sex-dependent risk factor for AD.
Conclusions: Current study showed no sex differences in the mean values of cognition, whereas higher intra-individual variability of short-term memory and attention switching was identified in women, indicating that their performance was lower on these cognitive abilities.
Ruytjens, Liesbet; Georgiadis, Janniko R.; Holstege, Gert; Wit, Hero P.; Albers, Frans W. J.; Willemsen, Antoon T. M.
Background We used PET to study cortical activation during auditory stimulation and found sex differences in the human primary auditory cortex (PAC). Regional cerebral blood flow (rCBF) was measured in 10 male and 10 female volunteers while listening to sounds (music or white noise) and during a
Rosenfeld, Cheryl S
Numbers of overweight and obese individuals are increasing in the United States and globally, and, correspondingly, the associated health care costs are rising dramatically. More than one-third of children are currently considered obese with a predisposition to type 2 diabetes, and it is likely that their metabolic conditions will worsen with age. Physical inactivity has also risen to be the leading cause of many chronic, noncommunicable diseases (NCD). Children are more physically inactive now than they were in past decades, which may be due to intrinsic and extrinsic factors. In rodents, the amount of time engaged in spontaneous activity within the home cage is a strong predictor of later adiposity and weight gain. Thus, it is important to understand primary motivators stimulating physical activity (PA). There are normal sex differences in PA levels in rodents and humans. The perinatal environment can induce sex-dependent differences in PA disturbances. This Review considers the current evidence for sex differences in PA in rodents and humans. The rodent studies showing that early exposure to environmental chemicals can shape later adult PA responses are discussed. Next, whether there are different motivators stimulating exercise in male vs. female humans are examined. Finally, the brain regions, genes, and pathways that modulate PA in rodents, and possibly by translation in humans, are described. A better understanding of why each sex remains physically active through the life span could open new avenues for preventing and treating obesity in children and adults. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Amr, Mostafa; Raddad, Dahoud; El-Mehesh, Fatima; Mahmoud, El-Hassanin; El-Gilany, Abdel-Hady
Although autism spectrum disorders (ASD) prevalence is higher in males than females in Arab countries, few studies address sex differences in autistic symptoms and coexiting behavioral problems. A total of 37 boys and 23 girls recruited from three Arab countries (Egypt, Saudi Arabia, Jordan) matched for age and IQ. They were compared using Indian…
Studies have reported no sex differences in variability of anthropometric characteristics, except in skinfolds with males more varied than females. Whether this is true of South African rural children is not known. The purpose of this study was to investigate the potential sexual anthropometric variability and verify its presence ...
Getz, Sandra K.; Herman, Jeanne B.
This study tests whether or not there are sex differences in judgments of the success of various male and female lifestyles, and if so, what differential standards are applied to males and females. The most interesting result of this study is that college men and women use the same standards to judge the success of male lifestyles but different…
Wong, Thessa M. L.; Loeber, Rolf; Slotboom, Anne-Marie; Bijleveld, Catrien C. J. H.; Hipwell, Alison E.; Stepp, Stephanie D.; Koot, Hans M.
This study examines sex differences in the risk threshold for adolescent delinquency. Analyses were based on longitudinal data from the Pittsburgh Youth Study (n = 503) and the Pittsburgh Girls Study (n = 856). The study identified risk factors, promotive factors, and accumulated levels of risks as predictors of delinquency and nondelinquency,…
McArthur, Laura H.; Raedeke, Thomas D.
Objectives: To assess sex/race differences on psychosocial correlates of physical activity among college students. Methods: Survey research protocol. Results: Students (n = 636) exercised an average of 3.5 days per week, with black females being the least active. Across subgroups, health/fitness was rated as the most important motive for exercise,…
Bao, Ai-Min; Swaab, Dick F.
Sex differences in the brain are reflected in behavior and in the risk for neuropsychiatric disorders. The fetal brain develops in the male direction due to a direct effect of testosterone on the developing neurons, or in the female direction due to the absence of such a testosterone surge. Because
Burman, Douglas D.; Bitan, Tali; Booth, James R.
Why females generally perform better on language tasks than males is unknown. Sex differences were here identified in children (ages 9-15) across two linguistic tasks for words presented in two modalities. Bilateral activation in the inferior frontal and superior temporal gyri and activation in the left fusiform gyrus of girls was greater than in…
Fedele, David A.; Lefler, Elizabeth K.; Hartung, Cynthia M.; Canu, Will H.
Objective: Given the mixed literature in the area, the aim of the current study was to determine whether sex differences exist in inattention, hyperactivity, and impairment in college adults with ADHD. Method: Individuals from three universities were recruited for the study. Participants with (n = 164) and without ADHD (n = 710) completed on-line…
Ignacio Zarragoitía Alonso
Full Text Available The article presents and analyzes the major factors involved in depression, taking into account those related to biological, psychological and social issues linked to sex and gender. Ultimately, these sex and gender-associated factors determine that the condition is present more often in women than in men, nearly doubling the cases. In addition, the article describes the singularities of depressive disorders in different reproductive periods when the disease acquires clinical specificity in accordance with sexual and hormonal functions. Finally, the way in which gender roles can intervene in how depression is approached in women vis-à-vis men is covered.
Mazur, Allan; Susman, Elizabeth J.; Edelbrock, Sandy
Testosterone (T) and cortisol (C) were assayed from saliva samples given by young men (n = 28) and women (n = 32) before, during, and after competing with a same-sex partner in a video game. The T response to the competition is different in each sex; the C response is the same. Male results confirm prior reports of a pre-contest rise in testosterone. Male results did not confirm previous findings that after a contest, the testosterone of winners is higher than that of losers, perhaps because ...
Full Text Available Cholesterol is linked to many multifactorial disorders, including different forms of liver disease where development and severity depend on the sex. We performed a detailed analysis of cholesterol and bile acid synthesis pathways at the level of genes and metabolites combined with the expression studies of hepatic cholesterol uptake and transport in female and male mice fed with a high-fat diet with or without cholesterol. Lack of dietary cholesterol led to a stronger response of the sterol sensing mechanism in females, resulting in higher expression of cholesterogenic genes compared to males. With cholesterol in the diet, the genes were down-regulated in both sexes; however, males maintained a more efficient hepatic metabolic flux through the pathway. Females had higher content of hepatic cholesterol but this was likely not due to diminished excretion but rather due to increased synthesis and absorption. Dietary cholesterol and sex were not important for gallbladder bile acids composition. Neither sex up-regulated Cyp7a1 upon cholesterol loading and there was no compensatory up-regulation of Abcg5 or Abcg8 transporters. On the other hand, females had higher expression of the Ldlr and Cd36 genes. These findings explain sexual dimorphism of cholesterol metabolism in response to dietary cholesterol in a high-fat diet in mice, which contributes to understanding the sex-basis of cholesterol-associated liver diseases.
Slagman, Anna; Searle, Julia; Vollert, Jörn O; Storchmann, Harald; Büschenfelde, Dirk Meyer Zum; von Recum, Johannes; Vlasny, Daniela; Ale-Abaei, Angela; Koch, Matthias; Müller, Christian; Müller, Reinhold; Somasundaram, Rajan; Möckel, Martin
Current guidelines recommend troponin as the preferred biomarker to diagnose acute myocardial infarction (AMI) irrespective of the patient's sex. Recent reports have shown that sex-specific cut-offs should be considered but studies investigating sex-differences in the diagnostic accuracy of cardiac troponins are sparse. To evaluate whether the diagnostic performance of cardiac troponin at admission (cTn) under routine conditions is influenced by patient's sex. Between 15th of February 2009 and 15th of February 2010, women (n=1648) and men (n=2305) who presented to the emergency department with chest pain (n=3954) were enrolled. The diagnostic performance of the routine, contemporary sensitive cTn assays (TnI; Stratus® CS, Siemens and TnT; Roche Diagnostics) at baseline for the diagnosis of non-ST-elevation myocardial infarction (NSTEMI) was analyzed. NSTEMI was diagnosed in 7.3% (n=287) of all patients. Men were more likely to be diagnosed with NSTEMI (8.8%; n=202) as compared to women (5.2%; n=85; psex, with a lower sensitivity and NPV in women. The definition and implementation of sex-specific cut-off values for cTn into clinical routine seems to be highly recommendable. Copyright © 2015. Published by Elsevier Ireland Ltd.
Zhang, Ya-Nan; Xia, Yi-Han; Zhu, Jia-Yao; Li, Sheng-Yun; Dong, Shuang-Lin
The general pathway of biosynthesis and degradation for Type-I sex pheromones in moths is well established, but some genes involved in this pathway remain to be characterized. The purple stem borer, Sesamia inferens, employs a pheromone blend containing components with three different terminal functional groups (Z11-16:OAc, Z11-16:OH, and Z11-16:Ald) of Type-I sex pheromones. Thus, it provides a good model to study the diversity of genes involved in pheromone biosynthesis and degradation pathways. By analyzing previously obtained transcriptomic data of the sex pheromone glands and antennae, we identified 73 novel genes that are possibly related to pheromone biosynthesis (46 genes) or degradation (27 genes). Gene expression patterns and phylogenetic analysis revealed that one desaturase (SinfDes4), one fatty acid reductase (SinfFAR2), and one fatty acid xtransport protein (SinfFATP1) genes were predominantly expressed in pheromone glands, and clustered with genes involved in pheromone synthesis in other moth species. Ten genes including five carboxylesterases (SinfCXE10, 13, 14, 18, and 20), three aldehyde oxidases (SinfAOX1, 2 and 3), and two alcohol dehydrogenases (SinfAD1 and 3) were expressed specifically or predominantly in antennae, and could be candidate genes involved in pheromone degradation. SinfAD1 and 3 are the first reported alcohol dehydrogenase genes with antennae-biased expression. Based on these results we propose a pathway involving these potential enzyme-encoding gene candidates in sex pheromone biosynthesis and degradation in S. inferens. This study provides robust background information for further elucidation of the genetic basis of sex pheromone biosynthesis and degradation, and ultimately provides potential targets to disrupt sexual communication in S. inferens for control purposes.
Fischette, Christine T.; Biegon, Anat; McEwen, Bruce S.
Male and female rats exhibit sex differences in binding by serotonin 1 receptors in discrete areas of the brain, some of which have been implicated in the control of ovulation and of gonadotropin release. The sex-specific changes in binding, which occur in response to the same hormonal (estrogenic) stimulus, are due to changes in the number of binding sites. Castration alone also affects the number of binding sites in certain areas. The results lead to the conclusion that peripheral hormones modulate binding by serotonin 1 receptors. The status of the serotonin receptor system may affect the reproductive capacity of an organism and may be related to sex-linked emotional disturbances in humans.
Zheng, Lijun; Lippa, Richard A; Zheng, Yong
Using data from an Internet survey, we assessed masculinity-femininity (self-ascribed masculinity-femininity [Self-MF], gender-related interests, instrumentality, expressiveness) and Big Five personality traits in a Chinese sample of 201 heterosexual men, 220 homosexual men, 353 heterosexual women, and 215 homosexual women. Sex differences and sexual orientation differences were largest for gender-related interests and Self-MF. Homosexual-heterosexual differences in emotional stability were opposite for men and women, supporting the "gender shift" over the "social stress" hypothesis. Sex and sexual orientation differences in gender-related interests, Self-MF, and emotional stability observed in China were consistent with those found in other countries, suggesting possible biological influences. In contrast, group differences in other traits were more variable, suggesting possible cultural influences.
Clougherty, Jane E; Eisen, Ellen A; Slade, Martin D; Kawachi, Ichiro; Cullen, Mark R
Studies have shown greater health risks associated with blue-collar manufacturing employment for women than men. It remains challenging, however, to distinguish gendered job status (affected by family composition and other personal characteristics) from sex-linked biological differences influencing physiological response to workplace physical hazards. We examined the effects of hourly (blue-collar) status on incident hypertension among men and women, using health claims data for 14, 618 white- and blue-collar aluminium manufacturing employees in eight US states. To explore gender differences in job status, we developed sex-stratified propensity score models identifying key socioeconomic predictors of hourly status for men and women. To examine the effects of hourly employment on hypertension risk, after adjusting for gender differences in job status, we applied time-weighted logistic regression models, stratified by propensity score, with additional adjustment for socioeconomic confounders. Family structure (partnership, parity) influenced job status for both sexes; single mothers were more likely to hold hourly jobs (OR 2.02; 95% CI 1.37 to 2.97) and partnered men with children less likely (OR 0.68; 95% CI 0.56 to 0.83). Education, age at hire and race influenced job status for both sexes. The effect of hourly status on hypertension was significant only among women predicted to be hourly (OR 1.78; 95% CI 1.34 to 2.35). Our results indicate significant risks of hypertension associated with hourly status for women, possibly exacerbated by sociodemographic factors predicting hourly status (eg, single parenthood, low education). Greater attention to gender differences in job status, and finer exploration of sex-linked biological differences influencing responsivity to workplace exposures, is warranted.
Lewis, Ben; Hoffman, Lauren A; Nixon, Sara Jo
Available evidence indicates women with substance use disorders may experience more rapid progression through usage milestones (telescoping). The few investigations of sex differences in treatment-seeking populations often focus on single substances and typically do not account for significant polysubstance abuse. The current study examined sex differences in a heterogeneous sample of treatment seeking polysubstance users. We examined patterns of drug use, age at drug use milestones (e.g., initial use, regular use), and progression rates between milestones. Nicotine and alcohol use were also evaluated. Participants (n = 543; 288 women) completed personal histories of substance use, including chronicity, frequency, and regularity, as well as inventories assessing affect, and intellectual ability. Rates of drug use and milestone ages varied by sex and specific drug. Analyses suggested pronounced telescoping effects for pain medication and marijuana, with women progressing more rapidly through usage milestones. Our data were generally supportive of telescoping effects, although considerable variance in progression measures was noted. The contrast between the marked telescoping observed in pain medication use and the absence of telescoping in other opioids was of particular interest. The discrepancy in telescoping effects, despite shared pharmacologies, suggests the need for further work examining underlying psychosocial factors. These results highlight that the specific sample population, substance, and outcome measure should be carefully considered when interpreting sex differences in substance use. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
Sundström Poromaa, Inger; Comasco, Erika; Georgakis, Marios K; Skalkidou, Alkistis
Women have a lifetime risk of major depression double that of men but only during their reproductive years. This sex difference has been attributed partially to activational effects of female sex steroids and also to the burdens of pregnancy, childbirth, and parenting. Men, in contrast, have a reproductive period difficult to delineate, and research on the mental health of men has rarely considered the effects of fatherhood. However, the couple goes through a number of potentially stressing events during the reproductive period, and both mothers and fathers are at risk of developing peripartum depression. This Review discusses the literature on maternal and paternal depression and the endocrine changes that may predispose a person to depression at this stage of life, with specific focus on the hypothalamus-pituitary axis, oxytocin, and testosterone levels in men. Important findings on sex differences in the neural correlates of maternal and paternal behavior have emerged, highlighting the relevance of the emotional brain in mothers and the sociocognitive brain in fathers and pointing toward the presence of a common parents' brain. Additionally, sex differences in neurogenesis and brain plasticity are described in relation to peripartum depression. © 2016 The Authors. Journal of Neuroscience Research Published by Wiley Periodicals, Inc. © 2016 The Authors. Journal of Neuroscience Research Published by Wiley Periodicals, Inc.
A large number of morphological, physiological and behavioural traits are differentially expressed by males and females in all vertebrates including humans. These sex differences, sometimes, reflect the different hormonal environment of the adults, but they often remain present after subjects of both sexes are placed in the same endocrine conditions following gonadectomy associated or not with hormonal replacement therapy. They are then the result of combined influences of organizational actions of sex steroids acting early during development, or genetic differences between the sexes, or epigenetic mechanisms differentially affecting males and females. Sexual partner preference is a sexually differentiated behavioural trait that is clearly controlled in animals by the same type of mechanisms. This is also probably true in humans, even if critical experiments that would be needed to obtain scientific proof of this assertion are often impossible for pragmatic or ethical reasons. Clinical, epidemiological and correlative studies provide, however, converging evidence strongly suggesting, if not demonstrating, that endocrine, genetic and epigenetic mechanisms acting during the pre- or perinatal life control human sexual orientation, i.e. homosexuality versus heterosexuality. Whether they interact with postnatal psychosexual influences remains, however, unclear at present. © 2016 The Author(s).
Popovich, C; Dockstader, C; Cheyne, D; Tannock, R
We used magnetoencephalography to investigate the effect of directed attention on sensorimotor mu (8-12 Hz) response (mu reactivity) to non-painful electrical stimulation of the median nerve in healthy adults. Mu desynchronization in the 10-12 Hz bandwidth is typically observed during higher-order cognitive functions including selective attentional processing of sensorimotor information (Pfurtscheller, Neuper, & Krauz, 2000). We found attention-related sex differences in mu reactivity, with females showing (i) prolonged mu desynchrony when attending to somatosensory stimuli, (ii) attentional modulation of the mu response based on whether attention was directed towards or away from somatosensory stimuli, which was absent in males, and (iii) a trend for greater neuronal excitability of the primary somatosensory region suggesting greater physiological responsiveness to sensory stimulation overall. Our findings suggest sex differences in attentional control strategies when processing somatosensory stimuli, whose salience may be greater for females. These sex differences in attention to somatosensory stimuli may help elucidate the well-documented sex biases in pain processing wherein females typically report greater sensitivity to experimental and clinical pain. Copyright © 2010 Elsevier Ltd. All rights reserved.
Full Text Available Abstract Background Changes in gene regulation are thought to be crucial for the adaptation of organisms to their environment. Transcriptome analyses can be used to identify candidate genes for ecological adaptation, but can be complicated by variation in gene expression between tissues, sexes, or individuals. Here we use high-throughput RNA sequencing of a single Drosophila melanogaster tissue to detect brain-specific differences in gene expression between the sexes and between two populations, one from the ancestral species range in sub-Saharan Africa and one from the recently colonized species range in Europe. Results Relatively few genes (Cyp6g1 and CHKov1. Conclusions Analysis of the brain transcriptome revealed many genes differing in expression between populations that were not detected in previous studies using whole flies. There was little evidence for sex-specific regulatory adaptation in the brain, as most expression differences between populations were observed in both males and females. The enrichment of genes with sexually dimorphic expression on the X chromosome is consistent with dosage compensation mechanisms affecting sex-biased expression in somatic tissues.
Filkowski, Megan M; Olsen, Rachel M; Duda, Bryant; Wanger, Timothy J; Sabatinelli, Dean
Behavioral and physiological sex differences in emotional reactivity are well documented, yet comparatively few neural differences have been identified. Here we apply quantitative activation likelihood estimation (ALE) meta-analysis across functional brain imaging studies that each reported clusters of activity differentiating men and women as they participated in emotion-evoking tasks in the visual modality. This approach requires the experimental paradigm to be balanced across the sexes, and thus may provide greater clarity than previous efforts. Results across 56 emotion-eliciting studies (n=1907) reveal distinct activation in the medial prefrontal cortex, anterior cingulate cortex, frontal pole, and mediodorsal nucleus of the thalamus in men relative to women. Women show distinct activation in bilateral amygdala, hippocampus, and regions of the dorsal midbrain including the periaqueductal gray/superior colliculus and locus coeruleus. While some clusters are consistent with prevailing perspectives on the foundations of sex differences in emotional reactivity, thalamic and brainstem regions have not previously been highlighted as sexually divergent. These data strongly support the need to include sex as a factor in functional brain imaging studies of emotion, and to extend our investigative focus beyond the cortex. Copyright © 2016 Elsevier Inc. All rights reserved.
Sagarin, Brad J
In a recent article, Harris (2003) concluded that the data do not support the existence of evolved sex differences in jealousy. Harris' review correctly identifies fatal flaws in three lines of evidence (spousal abuse, homicide, morbid jealousy), but her criticism of two other lines of evidence (self-report responses, psychophysiological measures) is based, in part, on a mischaracterization of the evolutionary psychological theory and a misunderstanding of the empirical implications of the theory. When interpreted according to the correct criterion (i.e., an interaction between sex and infidelity type), self-report studies (both forced-choice and non-forced choice) offer strong support for the existence of sex differences in jealousy. Psychophysiological data also offer some support, although these data are weakened by validity-related concerns. In addition, some refutational evidence cited by Harris (responses to real infidelity, responses under cognitive load) actually does not refute the theory. An integrative model that describes how jealousy might result from the interaction of sociocultural variables and evolved sex differences and suggestions for future research directions are discussed.
Furnham, Adrian; von Stumm, Sophie; Fenton-O'Creevy, Mark
This study examined sex differences in money beliefs and behaviours. Over 100,000 British participants completed two measures online, one of which assessed "money pathology" (Forman in Mind over money, Doubleday, Toronto, 1987), and the other four "money types", based on the emotional associations of money (Furnham et al. in Personal Individ Differ, 52:707-711, 2012). Nearly all measures showed significant sex differences with medium to large effect sizes, and with females exhibiting more "money pathology" than males. The biggest difference on the money types was on money being associated with generosity (money representing love) where men scored much lower than females, and autonomy (money representing freedom) where men scored higher than women. For men, more than women, money represented Power and Security. Men were more likely to be Hoarders while women did more emotional regulatory purchasing. Implications and limitations of this study are discussed.
and Therapy , 1970, 8, 353-366. 20. Singer, G., & Montgomery, R. B. Comment on roles of activation and inhibition in sex differences in cognitive...preference, and the sex difference. Sex Roles, 1975,1, 15-32. 13. Nielsen, J. M., & Doyle, P. T. Sex-role sterotypes of feminists and nonfeminists. Sex Roles
In the recent Demography article titled "The Effect of Same-Sex Marriage Laws on Different-Sex Marriage: Evidence From the Netherlands," Trandafir attempted to answer the question, Are rates of opposite sex marriage affected by legal recognition of same-sex marriages? The results of his approach to statistical inference-looking for evidence of a difference in rates of opposite-sex marriage-provide an absence of evidence of such effects. However, the validity of his conclusion of no causal relationship between same-sex marriage laws and rates of opposite-sex marriage is threatened by the fact that Trandafir did not also look for equivalence in rates of opposite-sex marriage in order to provide evidence of an absence of such an effect. Equivalence tests in combination with difference tests are introduced and presented in this article as a more valid inferential approach to the substantive question Trandafir attempted to answer.
Maryanne Fisher; Martin Voracek; P. Vivien Rekkas; Anthony Cox
Although there is extensive literature regarding sex differences in jealousy due to infidelity, guilt resulting from infidelity remains unexplored. We hypothesize that men will feel guiltier from imagined emotional rather than sexual infidelity, as it is most important for their partner's reproductive success. Similarly, we predict that women will feel more guilt from imagined sexual rather than emotional infidelity. The findings indicate a different pattern; men feel guiltier following sexua...
Olatunji, BO; Arrindell, WA; Lohr, JM
Recent research has shown a positive relationship between disgust sensitivity and blood-injection-injury (BII) fears. This line of research has also found that females report higher levels of BII fears and disgust sensitivity than males. The present study sought to determine if the sex difference in
Madenjian, Charles P.; Rediske, Richard R.; Krabbenhoft, David P.; Stapanian, Martin A.; Chernyak, Sergei M.; O'Keefe, James P.
Comparison of whole-fish polychlorinated biphenyl (PCB) and total mercury (Hg) concentrations in mature males with those in mature females may provide insights into sex differences in behavior, metabolism, and other physiological processes. In eight species of fish, we observed that males exceeded females in whole-fish PCB concentration by 17 to 43%. Based on results from hypothesis testing, we concluded that these sex differences were most likely primarily driven by a higher rate of energy expenditure, stemming from higher resting metabolic rate (or standard metabolic rate (SMR)) and higher swimming activity, in males compared with females. A higher rate of energy expenditure led to a higher rate of food consumption, which, in turn, resulted in a higher rate of PCB accumulation. For two fish species, the growth dilution effect also made a substantial contribution to the sex difference in PCB concentrations, although the higher energy expenditure rate for males was still the primary driver. Hg concentration data were available for five of the eight species. For four of these five species, the ratio of PCB concentration in males to PCB concentration in females was substantially greater than the ratio of Hg concentration in males to Hg concentration in females. In sea lamprey (Petromyzon marinus), a very primitive fish, the two ratios were nearly identical. The most plausible explanation for this pattern was that certain androgens, such as testosterone and 11-ketotestosterone, enhanced Hg-elimination rate in males. In contrast, long-term elimination of PCBs is negligible for both sexes. According to this explanation, males ingest Hg at a higher rate than females, but also eliminate Hg at a higher rate than females, in fish species other than sea lamprey. Male sea lamprey do not possess either of the above-specified androgens. These apparent sex differences in SMRs, activities, and Hg-elimination rates in teleost fishes may also apply, to some degree, to higher
Robinson, Michael E; Gagnon, Christine M; Dannecker, Erin A; Brown, Jennifer L; Jump, Rebecca L; Price, Donald D
This study examined (1) the effects of sex-related stereotypes in commonly experienced, potentially painful events and (2) differences in events representing the worst pain sensation imaginable for the typical woman and the typical man. Undergraduates (63 women and 54 men) completed the Situational Pain Questionnaire as the typical woman would and as the typical man would. The participants also answered 2 open-ended questions regarding the worst pain sensation imaginable for the typical woman and for the typical man. Our findings demonstrate that sex-related stereotypes extend to common pain events and that men and women expected that men would report less pain for common pain events than women. This suggests a gender-role related learning history that is relatively consistent for both sexes. The worst pain sensation imaginable was perceived to be different for typical men and women. Both sexes chose injury as the class of events men would find most painful and childbirth and menstrual pain as the class of events women would find most painful. Implications of this finding for common pain scaling approaches are discussed. The results of this study were obtained from a fairly uniform group of undergraduate men and women, which may limit the generalizability of our findings.
Rhodes, Anne E; Boyle, Michael H; Bridge, Jeffrey A; Sinyor, Mark; Links, Paul S; Tonmyr, Lil; Skinner, Robin; Bethell, Jennifer M; Carlisle, Corine; Goodday, Sarah; Hottes, Travis Salway; Newton, Amanda; Bennett, Kathryn; Sundar, Purnima; Cheung, Amy H; Szatmari, Peter
Suicide is the second leading cause of death in youth globally; however, there is uncertainty about how best to intervene. Suicide rates are typically higher in males than females, while the converse is true for suicide attempts. We review this “gender paradox” in youth, and in particular, the age-dependency of these sex/gender differences and the developmental mechanisms that may explain them. Epidemiologic, genetic, neurodevelopmental and psychopathological research have identified suicidal behaviour risks arising from genetic vulnerabilities and sex/gender differences in early adverse environments, neurodevelopment, mental disorder and their complex interconnections. Further, evolving sex-/gender-defined social expectations and norms have been thought to influence suicide risk. In particular, how youth perceive and cope with threats and losses (including conforming to others’ or one’s own expectations of sex/gender identity) and adapt to pain (through substance use and help-seeking behaviours). Taken together, considering brain plasticity over the lifespan, these proposed antecedents to youth suicide highlight the importance of interventions that alter early environment(s) (e.g., childhood maltreatment) and/or one’s ability to adapt to them. Further, such interventions may have more enduring protective effects, for the individual and for future generations, if implemented in youth. PMID:25540727
Ahrenfeldt, Linda J; Lindahl-Jacobsen, Rune; Möller, Sören; Christensen, Kaare; Hvidtjørn, Dorte; Hvidt, Niels Christian
Sex differences in religion are well known, with females generally being more religious than males, and shared environmental factors have been suggested to have a large influence on religiousness. Twins from opposite-sex (OS) and same-sex (SS) pairs may differ because of a dissimilar psycho-social rearing environment and/or because of different exposures to hormones in utero. We hypothesized that OS females may display more masculine patterns of religiousness and, vice versa, that OS males may display more feminine patterns. We used a web-based survey conducted in Denmark, which is a secular society. The survey included 2,997 twins aged 20-40 years, identified through the population-based Danish Twin Registry. We applied la Cour and Hvidt's adaptation of Fishman's three conceptual dimensions of meaning: Cognition, Practice, and Importance, and we used Pargament's measure of religious coping (RCOPE) for the assessment of positive and negative religious coping patterns. Differences between OS and SS twins were investigated using logistic regression for each sex. The analyses were adjusted for dependence within twin pairs. No significant differences in religiousness and religious coping were found for OS and SS twins except that more OS than SS females were members of the Danish National Evangelical Lutheran Church and fewer OS than SS females were Catholic, Muslim, or belonged to other religious denominations. Moreover, OS males at age 12 had higher rates of church attendance than did SS males. This study did not provide evidence for masculinization of female twins with male co-twins with regard to religiousness. Nor did it show any significant differences between OS and SS males except from higher rates of church attendance in childhood among males with female co-twins.
Hanifah, U.; Juniati, D.; Siswono, T. Y. E.
This study aims at describing the students’ spatial abilities based on cognitive styles and sex differences. Spatial abilities in this study include 5 components, namely spatial perception, spatial visualization, mental rotation, spatial relations, and spatial orientation. This research is descriptive research with qualitative approach. The subjects in this research were 4 students of junior high school, there were 1 male FI, 1 male FD, 1 female FI, and 1 female FI. The results showed that there are differences in spatial abilities of the four subjects that are on the components of spatial visualization, mental rotation, and spatial relations. The differences in spatial abilities were found in methods / strategies used by each subject to solve each component problem. The differences in cognitive styles and sex suggested different choice of strategies used to solve problems. The male students imagined the figures but female students needed the media to solve the problem. Besides sex, the cognitive style differences also have an effect on solving a problem. In addition, FI students were not affected by distracting information but FD students could be affected by distracting information. This research was expected to contribute knowledge and insight to the readers, especially for math teachers in terms of the spatial ability of the students so that they can optimize their students’ spatial ability.
Mutlu, A Kadir; Schneider, Maude; Debbané, Martin; Badoud, Deborah; Eliez, Stephan; Schaer, Marie
While significant differences in male and female brain structures have commonly been reported, only a few studies have focused on the sex differences in the way the cortex matures over time. Here, we investigated cortical thickness maturation between the age of 6 to 30 years, using 209 longitudinally-acquired brain MRI scans. Significant sex differences in the trajectories of cortical thickness change with age were evidenced using non-linear mixed effects models. Similar statistical analyses were computed to quantify the differences between cortical gyrification changes with age in males and females. During adolescence, we observed a statistically significant higher rate of cortical thinning in females compared to males in the right temporal regions, the left temporoparietal junction and the left orbitofrontal cortex. This finding is interpreted as a faster maturation of the social brain areas in females. Concomitantly, statistically significant sex differences in cortical folding changes with age were observed only in one cluster of the right prefrontal regions, suggesting that the mechanisms underlying cortical thickness and gyrification changes with age are quite distinct. Sexual dimorphism in the developmental course of the cortical maturation may be associated with the different age of onset and clinical presentation of many psychiatric disorders between males and females. Copyright © 2013 Elsevier Inc. All rights reserved.
Differences in frequency of postmyelographic adverse reactions were analyzed with respect to sex and age in a prospective study including 1026 patients injected with metrizamide and 739 injected with iohexol. Regardless of the type of contrast medium or myelography, all types of adverse reactions were 1.4-3.8 times as frequent in women as in men. Most of the differences were statistically significant. Headache was more frequent, while vomiting and dizziness were less frequent in both women and men aged 26-50 years compared with those over 50 years of age. Dizziness and increased low back pain were consistently reported spontaneously by the patients less frequently than emerged via formal interview. The large differences between the sexes suggest that further research on contrast media toxicity would be best performed with separation of the data by gender. (orig.)
Full Text Available Adults exposed to affective facial displays produce specific rapid facial reactions (RFRs which are of lower intensity in males compared to females. We investigated such sex difference in a population of 60 primary school children (30 F; 30 M, aged 7–10 years. We recorded the surface electromyographic (EMG signal from the corrugator supercilii and the zygomatici muscles, while children watched affective facial displays. Results showed the expected smiling RFR to smiling faces and the expected frowning RFR to sad faces. A systematic difference between male and female participants was observed, with boys showing less ample EMG responses than age-matched girls. We demonstrate that sex differences in the somatic component of affective motor patterns are present also in childhood.
Howard, J. Paul R.
The Ontario and British Columbia courts of appeal have held that the restriction of marriage to heterosexuals is unconstitutional. Opposing views in same-sex marriage litigation arise from different definitions of "marriage." Proposed federal legislation would legalize same-sex marriage but not resolve the larger, underlying issue of how…
Kendler, Kenneth S; Gardner, Charles O
The authors sought to clarify the nature of sex differences in the etiologic pathways to major depression. Retrospective and prospective assessments of 20 developmentally organized risk factors and the occurrence of past-year major depression were conducted at two waves of personal interviews at least 12 months apart in 1,057 opposite-sex dizygotic twin pairs from a population-based register. Analyses were conducted by structural modeling, examining within-pair differences. Sixty percent of all paths in the best-fit model exhibited sex differences. Eleven of the 20 risk factors differed across sexes in their impact on liability to major depression. Five had a greater impact in women: parental warmth, neuroticism, divorce, social support, and marital satisfaction. Six had a greater impact in men: childhood sexual abuse, conduct disorder, drug abuse, prior history of major depression, and distal and dependent proximal stressful life events. The life event categories responsible for the stronger effect in males were financial, occupational, and legal in nature. In a co-twin control design, which matches sisters and brothers on genetic and familial-environmental background, personality and failures in interpersonal relationships played a stronger etiologic role in major depression for women than for men. Externalizing psychopathology, prior depression, and specific "instrumental" classes of acute stressors were more important in the etiologic pathway to major depression for men. The results are consistent with previously proposed typologies of major depression that suggest two subtypes that differ in prevalence in women (deficiencies in caring relationships and interpersonal loss) and men (failures to achieve expected goals, with lowered self-worth).
Solianik, Rima; Brazaitis, Marius; Skurvydas, Albertas
The sex differences and similarities in cognitive abilities is a continuing topic of major interest. Besides, the influences of trends over time and possible effects of sex steroid and assessment time on cognition have expanded the necessity to re-evaluate differences between men and women. Therefore, the aim of this study was to compare cognitive performance between men and women in a strongly controlled experiment. In total, 28 men and 25 women were investigated. Variables of body temperature and heart rate were assessed. A cognitive test battery was used to assess attention (visual search, unpredictable task switching as well as complex visual search and predictable task switching tests) and memory (forced visual memory, forward digit span and free recall test). The differences in heart rate and body temperatures between men and women were not significant. There were no differences in the mean values of attention and memory abilities between men and women. Coefficients of variation of unpredictable task switching response and forward digit span were lower (Pattention task incorrect response and negatively correlated (Pmemory task. Current study showed no sex differences in the mean values of cognition, whereas higher intra-individual variability of short-term memory and attention switching was identified in women, indicating that their performance was lower on these cognitive abilities. Copyright © 2016 The Lithuanian University of Health Sciences. Production and hosting by Elsevier Urban & Partner Sp. z o.o. All rights reserved.
Young, Kymberly D; Bellgowan, Patrick S F; Bodurka, Jerzy; Drevets, Wayne C
Autobiographical memory (AM) is episodic memory for personally experienced events. The brain areas underlying AM retrieval are known to include several prefrontal cortical and medial temporal lobe regions. Sex differences in AM recall have been reported in several behavioral studies, but the functional anatomical correlates underlying such differences remain unclear. This study used fMRI to compare the neural correlates of AM recall between healthy male and female participants (n = 20 per group). AM recall in response to positive, negative, and neutral cue words was compared to a semantic memory task involving the generation of examples from a category using emotionally valenced cues. Behaviorally, females recalled more negative and fewer positive AMs compared with males, while ratings of arousal, vividness, and memory age did not differ significantly between sexes. Males and females also did not differ significantly in their performance on control tasks. Neurophysiologically, females showed increased hemodynamic activity compared to males in the dorsolateral prefrontal cortex (DLPFC), dorsal anterior insula, and precuneus while recalling specific AMs (all valences combined); increased activity in the DLPFC, transverse temporal gyrus, and precuneus while recalling positive AMs; and increased activity in the anterior cingulate cortex, precuneus, amygdala, and temporopolar cortex when recalling negative AMs. When comparing positive to negative AMs directly, males and females differed in their BOLD responses in the hippocampus and DLPFC. We propose that the differential hemodynamic changes may reflect sex-specific cognitive strategies during recall of AMs irrespective of the phenomenological properties of those memories. Copyright © 2012 Wiley Periodicals, Inc.
Sherman, Gary D; Rice, Leslie K; Jin, Ellie Shuo; Jones, Amanda C; Josephs, Robert A
A contribution to a special issue on Hormones and Human Competition. A stress perspective is used to illuminate how competitive defeat and victory shape biology and behavior. We report a field study examining how change in cortisol following perceived defeat (vs. victory) in a competition-in this case, a dog agility competition-relates to affiliative behavior. Following competition, we measured cortisol change and the extent to which dog handlers directed affiliative behaviors toward their dogs. We found striking sex differences in affiliation. First, men were more affiliative toward their dogs after victory, whereas women were more affiliative after defeat. Second, the greater a female competitor's increase in cortisol, the more time she spent affiliating with her dog, whereas for men, the pattern was the exact opposite: the greater a male competitor's increase in cortisol, the less time he spent affiliating with his dog. This pattern suggests that, in the wake of competition, men and women's affiliative behavior may serve different functions-shared celebration for men; shared consolation for women. These sex differences show not only that men and women react very differently to victory and defeat, but also that equivalent changes in cortisol across the sexes are associated with strikingly different behavioral consequences for men and women. Copyright © 2016 Elsevier Inc. All rights reserved.
Shah, Darshna S; Prados, Jose; Gamble, Jasmin; De Lillo, Carlo; Gibson, Claire L
The present study assessed the spatial abilities of male and female human participants using different versions of the non-navigational Corsi block-tapping test (CBT) and a search task. Males performed significantly better than females on the standard manual version of the CBT; however, the standard CBT does not allow discrimination between spatial memory span and the role of spatial organisational factors (structure, path length and presence of crossings) in the sequences to recall. These organisational factors were assessed, therefore, in an experiment in which 7-block-sequences had to be recalled in a computerised version of the CBT. No sex differences in performance were observed on the computerised CBT, indicating that males do not make better use of spatial organisational principles. Accordingly, sex differences observed in the manual CBT are likely to rely upon differences in memory span between males and females. In the search task, participants could locate a goal by reference to a Euclidian space (the geometry of a virtual enclose) or to proximal non-geometric cues. Both male and female participants showed a preference for the non-geometric cues, which overshadowed learning about the geometric cues when the two sets were available simultaneously during the training stage. These results indicate that sex differences do exist in those tests which are dependent on memory span. Sex differences were absent, however, in spatial organisational skills or in the usage of Euclidian and egocentric strategies to solve problems relying on spatial ability. Copyright © 2013 Elsevier B.V. All rights reserved.
Developmental and seasonal changes in the production of androgens, estrogens, and progestins seem to control sex-specific differentiation and seasonal changes in appetitive and consummatory sexual behaviors of birds. This results in profound sex differences in the quality (sex-specific) or quantity
Gary L. Brase
Full Text Available To the extent that sex differences are mediated by mechanisms such as sex-roles and beliefs, individual differences in these more proximate traits should account for significant portions of relevant sex differences. Differences between women and men in reactions to sexual and emotional infidelity were assessed in a large sample of participants (n = 477, and these target reactions were evaluated as a function of many potential proximate mediators (infidelity implications beliefs, gender-role beliefs, interpersonal trust, attachment style, sociosexuality, and culture of honor beliefs and as a function of participant sex. Results found a consistent sex difference that was not mediated by any other variables, although a handful of other variables were related to male, but not female, individual differences. These findings suggest particularly promising directions for future research on integrating evolutionarily based sex differences and proximate individual differences.
Brase, Gary L; Adair, Lora; Monk, Kale
To the extent that sex differences are mediated by mechanisms such as sex-roles and beliefs, individual differences in these more proximate traits should account for significant portions of relevant sex differences. Differences between women and men in reactions to sexual and emotional infidelity were assessed in a large sample of participants (n = 477), and these target reactions were evaluated as a function of many potential proximate mediators (infidelity implications beliefs, gender-role beliefs, interpersonal trust, attachment style, sociosexuality, and culture of honor beliefs) and as a function of participant sex. Results found a consistent sex difference that was not mediated by any other variables, although a handful of other variables were related to male, but not female, individual differences. These findings suggest particularly promising directions for future research on integrating evolutionarily based sex differences and proximate individual differences.
Full Text Available Lifestyle intervention programs are effective in the prevention of type 2 diabetes mellitus (T2DM in high risk populations. However, most studies only give limited information about the influence of sex and/or gender effectiveness of these interventions. So far, similar outcome was reported for diabetes progression and weight loss. Nevertheless, long-term data on cardiovascular outcome are sparse but favoring women regarding all-cause and cardiovascular mortality. In both men and women, sex hormone imbalances and reproductive disorders are associated with a higher risk of T2DM development. Diabetes prevention approaches are reported for polycystic ovary syndrome, gestational diabetes mellitus, and erectile dysfunction and are presented in this review. In the surgical treatment options for morbid obese patients, sex and gender differences are present. Choices and preferences of adherence to lifestyle and pharmacological interventions, expectations, treatment effects, and complications are influenced by sex or gender. In general, bariatric surgery is performed more often in women seeking medical/surgical help to lose weight. Men are older and have higher comorbidities and mortality rates and worse follow-up outcome after bariatric surgery. A more gender-sensitive clinical approach, as well as consideration of ethnicity may improve quality of life and increase health and life expectancy in men and women with a high risk for subsequent progression to T2DM.
White, Brandi M; Magwood, Gayenell S; Burns, Suzanne Perea; Ellis, Charles
Recent studies have shown that stroke has a differential impact in women compared to men. Women are more likely to survive strokes than men, yet they experience more severe strokes resulting in greater poststroke disability. However, few studies have characterized sex differences in functional ability after stroke. This study examined sex differences in long-term disability among stroke survivors. This was a retrospective analysis of the 2015 National Health Interview Survey. Respondents were asked to rate their ability to perform 11 functional tasks. Univariate comparisons were completed to evaluate sex differences in performance, and multinomial logistic regression was used to determine the odds of reporting functional limitations. Five hundred fourteen men and 641 women stroke survivors completed the survey (mean age: 66.9 years). Approximately 75% of the sample reported having hypertension, 61% high cholesterol, 33% diabetes, 24% heart disease, 21% heart attack, and 16% chronic obstructive pulmonary disease. In the predictive models, men were less likely to report "very difficult/can't do at all" in walking ¼ mile (odds ratios [OR] = 0.68, 95% CI 0.51-0.90), climbing 10 steps (OR = 0.65, 95% CI 0.49-0.85), standing 2 hours (OR = 0.66, 95% CI 0.50-0.87), stooping (OR = 0.51, 95% CI 0.39-0.68), reaching overhead (OR = 0.69, 95% CI 0.49-0.97), carrying 10 pounds (OR = 0.45, 95% CI 0.34-0.59), and pushing large objects (OR = 0.37, 95% CI 0.28-0.5) compared to women. The functional outcomes of men stroke survivors were significantly greater than women. The specific factors that contribute to sex differences in stroke-related outcomes are not entirely clear. Future research is needed to better understand these differences to ensure that equity of care is received.
Ingalhalikar, Madhura; Smith, Alex; Parker, Drew; Satterthwaite, Theodore D; Elliott, Mark A; Ruparel, Kosha; Hakonarson, Hakon; Gur, Raquel E; Gur, Ruben C; Verma, Ragini
Sex differences in human behavior show adaptive complementarity: Males have better motor and spatial abilities, whereas females have superior memory and social cognition skills. Studies also show sex differences in human brains but do not explain this complementarity. In this work, we modeled the structural connectome using diffusion tensor imaging in a sample of 949 youths (aged 8-22 y, 428 males and 521 females) and discovered unique sex differences in brain connectivity during the course of development. Connection-wise statistical analysis, as well as analysis of regional and global network measures, presented a comprehensive description of network characteristics. In all supratentorial regions, males had greater within-hemispheric connectivity, as well as enhanced modularity and transitivity, whereas between-hemispheric connectivity and cross-module participation predominated in females. However, this effect was reversed in the cerebellar connections. Analysis of these changes developmentally demonstrated differences in trajectory between males and females mainly in adolescence and in adulthood. Overall, the results suggest that male brains are structured to facilitate connectivity between perception and coordinated action, whereas female brains are designed to facilitate communication between analytical and intuitive processing modes.
Mendiguchia, Jurdan; Ford, Kevin R; Quatman, Carmen E; Alentorn-Geli, Eduard; Hewett, Timothy E
Following the onset of maturation, female athletes have a significantly higher risk for anterior cruciate ligament (ACL) injury compared with male athletes. While multiple sex differences in lower-extremity neuromuscular control and biomechanics have been identified as potential risk factors for ACL injury in females, the majority of these studies have focused specifically on the knee joint. However, increasing evidence in the literature indicates that lumbo-pelvic (core) control may have a large effect on knee-joint control and injury risk. This review examines the published evidence on the contributions of the trunk and hip to knee-joint control. Specifically, the sex differences in potential proximal controllers of the knee as risk factors for ACL injury are identified and discussed. Sex differences in trunk and hip biomechanics have been identified in all planes of motion (sagittal, coronal and transverse). Essentially, female athletes show greater lateral trunk displacement, altered trunk and hip flexion angles, greater ranges of trunk motion, and increased hip adduction and internal rotation during sport manoeuvres, compared with their male counterparts. These differences may increase the risk of ACL injury among female athletes. Prevention programmes targeted towards trunk and hip neuromuscular control may decrease the risk for ACL injuries.
Madenjian, Charles P.; Trombka, Autumn W.; Rediske, Richard R.; Jude, David J.; O'Keefe, James P.
Polybrominated diphenyl ether (PBDE) concentrations were determined for mature male and mature female walleyes (Sander vitreus) sampled from the Saginaw Bay population during 2007. PBDE concentrations in prey fish caught in the Saginaw River, the primary tributary to Saginaw Bay, and in Saginaw Bay during 2005 and 2007 also were determined. Mature male and mature female walleyes averaged 70.3 ng/g and 24.8 ng/g, respectively, in ΣPBDE, which was equal to the sum of concentrations of six PBDE congeners (BDE-28, BDE-47, BDE-99, BDE-100, BDE-153, and BDE-154). This sex difference was likely due to males spending more time in the Saginaw River system than females. Prey fish captured in the Saginaw River were roughly ten times higher in ΣPBDE than those caught in Saginaw Bay. BDE-47 was the predominant congener in both walleyes and prey fish, and this congener contributed about 50%, on average, to ΣPBDE. Congener profiles differed significantly between the two sexes of walleyes. In contrast, congener profiles of the prey fish did not differ significantly between the river-caught fish and the bay-caught fish. One plausible explanation for these congener profile results was that net trophic transfer efficiencies of PBDEs to walleyes from their prey were similar for all congeners except BDE-28, and that diet composition differed between the two sexes of walleyes.
Mendiguchia, Jurdan; Ford, Kevin R.; Quatman, Carmen E.; Alentorn-Geli, Eduard; Hewett, Timothy E.
Following the onset of maturation, female athletes have a significantly higher risk for anterior cruciate ligament (ACL) injury compared with male athletes. While multiple sex differences in lower-extremity neuromuscular control and biomechanics have been identified as potential risk factors for ACL injury in females, the majority of these studies have focused specifically on the knee joint. However, increasing evidence in the literature indicates that lumbopelvic (core) control may have a large effect on knee-joint control and injury risk. This review examines the published evidence on the contributions of the trunk and hip to knee-joint control. Specifically, the sex differences in potential proximal controllers of the knee as risk factors for ACL injury are identified and discussed. Sex differences in trunk and hip biomechanics have been identified in all planes of motion (sagittal, coronal and transverse). Essentially, female athletes show greater lateral trunk displacement, altered trunk and hip flexion angles, greater ranges of trunk motion, and increased hip adduction and internal rotation during sport manoeuvres, compared with their male counterparts. These differences may increase the risk of ACL injury among female athletes. Prevention programmes targeted towards trunk and hip neuromuscular control may decrease the risk for ACL injuries. PMID:21688868
Doty, Richard L.; Cameron, E. Leslie
The question of whether men and women differ in their ability to smell has been the topic of scientific investigation for over a hundred years. Although conflicting findings abound, most studies suggest that, for at least some odorants, women outperform men on tests of odor detection, identification, discrimination, and memory. Most functional imaging and electrophysiological studies similarly imply that, when sex differences are present, they favor women. In this review we examine what is known about sex-related alterations in human smell function, including influences of the menstrual cycle, pregnancy, gonadectomy, and hormone replacement therapy on a range of olfactory measures. We conclude that the relationship between reproductive hormones and human olfactory function is complex and that simple associations between circulating levels of gonadal hormones and measures of olfactory function are rarely present. PMID:19272398
Kraines, Morganne A; Kelberer, Lucas J A; Wells, Tony T
Research demonstrates that women experience disgust more readily and with more intensity than men. The experience of disgust is associated with increased attention to disgust-related stimuli, but no prior study has examined sex differences in attention to disgust facial expressions. We hypothesised that women, compared to men, would demonstrate increased attention to disgust facial expressions. Participants (n = 172) completed an eye tracking task to measure visual attention to emotional facial expressions. Results indicated that women spent more time attending to disgust facial expressions compared to men. Unexpectedly, we found that men spent significantly more time attending to neutral faces compared to women. The findings indicate that women's increased experience of emotional disgust also extends to attention to disgust facial stimuli. These findings may help to explain sex differences in the experience of disgust and in diagnoses of anxiety disorders in which disgust plays an important role.
Klump, Kelly L; Culbert, Kristen M; Sisk, Cheryl L
Eating disorders are highly sexually differentiated disorders that exhibit a female predominance in risk. Most theories focus on psychosocial explanations to the exclusion of biological/genetic influences. The purpose of this descriptive review is to evaluate evidence from animal and human studies in support of gonadal hormone effects on sex differences in binge eating. Although research is in its nascent stages, findings suggest that increased prenatal testosterone exposure in males appears to protect against binge eating. Although pubertal testosterone may exert additional protective effects, the prenatal period is likely critical for the decreased risk observed in males. By contrast, studies indicate that, in females, it is the lack of prenatal testosterone coupled with the organizational effects of pubertal ovarian hormones that may lead to increased binge eating. Finally, twin data suggest that changes in genetic risk may underlie these hormone influences on sex differences across development.
Margaret M Mccarthy
Full Text Available The notion that epigenetics may play an important role in the establishment and maintenance of sex differences in the brain has garnered great enthusiasm but the reality in terms of actual advances have been slow. Two general approaches include the comparison of a particular epigenetic mark in males versus females and the inhibition of key epigenetic enzymes or co-factors to determine if this eliminates a particular sex difference in brain or behavior. The majority of emphasis has been on candidate genes such as steroid receptors. Only recently have more generalized survey type approaches been achieved and these promise to open new vista’s and accelerate discovery of important roles for DNA methylation, histone modification and microRNAs. Technical challenges abound and while not unique to this field will require novel thinking and new approaches by behavioral neuroendocrinogists.
The phenomenon of higher rates of affective disorders in women illustrates many of the difficulties as well as promises of translating preclinical models to human disorders. Abnormalities in the regulation of the hypothalamic-pituitary adrenal axis and the sympathoadrenomedullary system have been identified in depression and anxiety disorders, and these disorders are clearly precipitated and exacerbated by stress. Despite the striking sex difference in the prevalence of depression and anxiety disorders, attempts to identify corresponding sex differences in stress response reactivity in animal models have met with limited success. Processes which may contribute to increased rates of affective disorders in women are greater fluxes in reproductive hormones across the life span, and increased sensitivity to catecholamine augmentation of emotional memory consolidation.
Full Text Available Although there is extensive literature regarding sex differences in jealousy due to infidelity, guilt resulting from infidelity remains unexplored. We hypothesize that men will feel guiltier from imagined emotional rather than sexual infidelity, as it is most important for their partner's reproductive success. Similarly, we predict that women will feel more guilt from imagined sexual rather than emotional infidelity. The findings indicate a different pattern; men feel guiltier following sexual infidelity, whereas women feel guiltier following emotional infidelity. Results also show that both sexes believe their partners would have a more difficult time forgiving sexual, rather than emotional, infidelity, but women and not men report that sexual infidelity would more likely lead to relationship dissolution. These findings are discussed in view of evolved mating strategies and individual reproductive success.
Ito E; Iwamoto J; Azuma K; Matsumoto H
Eri Ito, Jun Iwamoto, Koichiro Azuma, Hideo MatsumotoInstitute for Integrated Sports Medicine, Keio University School of Medicine, Tokyo, JapanAbstract: The purpose of the present study was to investigate sex-specific differences in injury types among basketball players. According to our database, during the 20-year period between October 1991 and June 2011, 1,219 basketball players (640 males and 579 females) consulted our sports medicine clinic; in total, 1,414 injuries in basketball player...
Mendiguchia, Jurdan; Ford, Kevin R.; Quatman, Carmen E.; Alentorn-Geli, Eduard; Hewett, Timothy E.
Following the onset of maturation, female athletes have a significantly higher risk for anterior cruciate ligament (ACL) injury compared with male athletes. While multiple sex differences in lower-extremity neuromuscular control and biomechanics have been identified as potential risk factors for ACL injury in females, the majority of these studies have focused specifically on the knee joint. However, increasing evidence in the literature indicates that lumbopelvic (core) control may have a la...
Šlamberová, R.; Mikulecká, Anna; Pometlová, M.; Schutová, B.; Hrubá, L.; Deykun, K.
Roč. 22, č. 7 (2011), s. 617-623 ISSN 0955-8810 R&D Projects: GA MŠk(CZ) 1M0517 Grant - others:GA ČR(CZ) GAP303/10/0580 Institutional research plan: CEZ:AV0Z50110509 Keywords : estrogen * methamphetamine * rat * sex difference * social behavior * testosterone Subject RIV: FH - Neurology Impact factor: 2.720, year: 2011
Goran Gojković; Branislav Radulović
As per sample of 212 examinees at the age of 11 (±6 months) at the fifth grade in Montenegrin elementary schools, it was used the system of 12 variables for the estimation of anthropometrical characteristis. The purpose of the examination was to establish differentiations between different students sex in the initial and final measuring. As for results given by using discriminant analysis and univariant analysis of variance on the anthropometrical student's status, it can be concluded that th...
Chuang, Jie-Yu; Hagan, Cindy C; Murray, Graham K; Graham, Julia M E; Ooi, Cinly; Tait, Roger; Holt, Rosemary J; Elliott, Rebecca; van Nieuwenhuizen, Adrienne O; Bullmore, Edward T; Lennox, Belinda R; Sahakian, Barbara J; Goodyer, Ian M; Suckling, John
Compared to female major depressive disorder (MDD), male MDD often receives less attention. However, research is warranted since there are significant sex differences in the clinical presentation of MDD and a higher rate of suicide in depressed men. To the best of our knowledge, this is the first functional magnetic resonance imaging (fMRI) study with a large sample addressing putative sex differences in MDD during adolescence, a period when one of the most robust findings in psychiatric epidemiology emerges; that females are twice as likely to suffer from MDD than males. Twenty-four depressed and 10 healthy male adolescents, together with 82 depressed and 24 healthy female adolescents, aged 11-18 years, undertook an affective go/no-go task during fMRI acquisition. In response to sad relative to neutral distractors, significant sex differences (in the supramarginal gyrus) and group-by-sex interactions (in the supramarginal gyrus and the posterior cingulate cortex) were found. Furthermore, in contrast to the healthy male adolescents, depressed male adolescents showed decreased activation in the cerebellum with a significant group-by-age interaction in connectivity. Future research may consider altered developmental trajectories and the possible implications of sex-specific treatment and prevention strategies for MDD.
Full Text Available Compared to female major depressive disorder (MDD, male MDD often receives less attention. However, research is warranted since there are significant sex differences in the clinical presentation of MDD and a higher rate of suicide in depressed men. To the best of our knowledge, this is the first functional magnetic resonance imaging (fMRI study with a large sample addressing putative sex differences in MDD during adolescence, a period when one of the most robust findings in psychiatric epidemiology emerges; that females are twice as likely to suffer from MDD than males. Twenty-four depressed and 10 healthy male adolescents, together with 82 depressed and 24 healthy female adolescents, aged 11–18 years, undertook an affective go/no-go task during fMRI acquisition. In response to sad relative to neutral distractors, significant sex differences (in the supramarginal gyrus and group-by-sex interactions (in the supramarginal gyrus and the posterior cingulate cortex were found. Furthermore, in contrast to the healthy male adolescents, depressed male adolescents showed decreased activation in the cerebellum with a significant group-by-age interaction in connectivity. Future research may consider altered developmental trajectories and the possible implications of sex-specific treatment and prevention strategies for MDD.
Gardner, Mark R; Sorhus, Ingrid; Edmonds, Caroline J; Potts, Rosalind
Little research to date has examined whether sex differences in spatial ability extend to the mental self rotation involved in taking on a third party perspective. This question was addressed in the present study by assessing components of imagined perspective transformations in twenty men and twenty women. Participants made speeded left-right judgements about the hand in which an object was held by front- and back- facing schematic human figures in an "own body transformation task." Response times were longer when the figure did not share the same spatial orientation as the participant, and were substantially longer than those made for a control task requiring left-right judgements about the same stimuli from the participant's own point of view. A sex difference in imagined perspective transformation favouring males was found to be restricted to the speed of imagined self rotation, and was not observed for components indexing readiness to take a third party point of view, nor in left-right confusion. These findings indicate that the range of spatial abilities for which a sex difference has been established should be extended to include imagined perspective transformations. They also suggest that imagined perspective transformations may not draw upon those empathic social-emotional perspective taking processes for which females show an advantage. Copyright © 2012 Elsevier B.V. All rights reserved.
Araya, Ricardo; Montero-Marin, Jesus; Barroilhet, Sergio; Fritsch, Rosemarie; Gaete, Jorge; Montgomery, Alan
Depression among adolescents is common but most cases go undetected. Brief questionnaires offer an opportunity to identify probable cases but properly validated cut-off points are often unavailable, especially in non-western countries. Sex differences in the prevalence of depression become marked in adolescence and this needs to be accounted when establishing cut-off points. This study involved adolescents attending secondary state schools in Santiago, Chile. We compared the self-reported Beck Depression Inventory-II with a psychiatric interview to ascertain diagnosis. General psychometric features were estimated before establishing the criterion validity of the BDI-II. The BDI-II showed good psychometric properties with good internal consistency, a clear unidimensional factorial structure, and good capacity to discriminate between cases and non-cases of depression. Optimal cut-off points to establish caseness for depression were much higher for girls than boys. Sex discrepancies were primarily explained by differences in scores among those with depression rather than among those without depression. It is essential to validate scales with the populations intended to be used with. Sex differences are often ignored when applying cut-off points, leading to substantial misclassification. Early detection of depression is essential if we think that early intervention is a clinically important goal.
Lagro-Janssen, Toine; Grosicar, Janja
Trauma prevention starts with to find out the extent of the problem and who it affects. Insight into morbidity figures is therefore necessary. To explore sex differences in traumatology and secondary medical care utilization in primary care related to age and socio-economic status (SES). Data were obtained from an academic continuous morbidity registration project in the Netherlands in the period from 1996 to 2006, in which 13,000 patients were followed in 10 successive years. Sex differences showed a male excess from childhood to 45 years and women showing almost double trauma rates in the elderly. Low SES was associated with the greatest incidence of traumas. The largest sex difference in incidence above 65 years appeared in the high SES with more traumas in women compared with men. From this age on, female morbidity in traumatology outnumbered male morbidity regardless of SES. Considering use of referrals, we found that in the age group 15-45 years men made a greater use of secondary medical care. However, the vastest gender influence in medical care utilization was noticed in the age group over 65 years, outnumbered with women. Young men and old women are the most at risk for traumatic health problems: men presenting with traumata of the skull, the tibia and ocular trauma's and women with fractures of the femur, humerus and wrist. For both men and women the greatest incidence is in the low SES. Family physicians can play a pivotal role in prevention to focus on their patients with high risks.
Prior, M; Smart, D; Sanson, A; Oberklaid, F
The objective of this study was to explore sex differences in development from infancy to 8 years of age in a community sample. Measures of biological, social, interactive, and parental functioning as well as teacher reports were obtained. There were minimal differences in infancy, but major psychosocial differences emerged with increasing age. In the biological sphere boys were disadvantaged only in ratings of language and motor skills at 3 to 4 years old. They showed greater temperamental "difficulty" and low persistence factor scores from 5 years onward. Boys were significantly more likely to have problems with adaptive behavior and social competence and to show behavior problems of the hyperactive and aggressive type, as rated by mothers. Parent and family functioning measures did not differentiate between the sexes. Teachers rated boys as having more problems in academic and behavioral domains the first 3 years of school. Path analyses combining data sets gathered when the children were 3 to 8 years old demonstrated the differential courses of development for boys and girls although temperamental flexibility was the best predictor of behavioral adjustment for both sexes. A social learning explanation of the increased incidence of problems among males is supported, although biological influences are not ruled out.
Boose, Klaree J; White, Frances J; Meinelt, Audra
All the great ape species are known tool users in both the wild and captivity, although there is great variation in ability and behavioral repertoire. Differences in tool use acquisition between chimpanzees and gorillas have been attributed to differing levels of social tolerance as a result of differences in social structure. Chimpanzees also show sex differences in acquisition and both chimpanzees and bonobos demonstrate a female bias in tool use behaviors. Studies of acquisition are limited in the wild and between species comparisons are complicated in captivity by contexts that often do not reflect natural conditions. Here we investigated tool use acquisition in a captive group of naïve bonobos by simulating naturalistic conditions. We constructed an artificial termite mound fashioned after those that occur in the wild and tested individuals within a social group context. We found sex differences in latencies to attempt and to succeed where females attempted to fish, were successful more quickly, and fished more frequently than males. We compared our results to those reported for chimpanzees and gorillas. Males across all three species did not differ in latency to attempt or to succeed. In contrast, bonobo and chimpanzee females succeeded more quickly than did female gorillas. Female bonobos and female chimpanzees did not differ in either latency to attempt or to succeed. We tested the social tolerance hypothesis by investigating the relationship between tool behaviors and number of neighbors present. We also compared these results to those reported for chimpanzees and gorillas and found that bonobos had the fewest numbers of neighbors present. The results of this study do not support the association between number of neighbors and tool behavior reported for chimpanzees. However, bonobos demonstrated a similar sex difference in tool use acquisition, supporting the hypothesis of a female bias in tool use in Pan. © 2013 Wiley Periodicals, Inc.
Kappus, Rebecca M; Ranadive, Sushant M; Yan, Huimin; Lane-Cordova, Abbi D; Cook, Marc D; Sun, Peng; Harvey, I Shevon; Wilund, Kenneth R; Woods, Jeffrey A; Fernhall, Bo
Heart rate variability (HRV), blood pressure variability, (BPV) and heart rate recovery (HRR) are measures that provide insight regarding autonomic function. Maximal exercise can affect autonomic function, and it is unknown if there are sex differences in autonomic recovery following exercise. Therefore, the purpose of this study was to determine sex differences in several measures of autonomic function and the response following maximal exercise. Seventy-one (31 males and 40 females) healthy, nonsmoking, sedentary normotensive subjects between the ages of 18 and 35 underwent measurements of HRV and BPV at rest and following a maximal exercise bout. HRR was measured at minute one and two following maximal exercise. Males have significantly greater HRR following maximal exercise at both minute one and two; however, the significance between sexes was eliminated when controlling for VO2 peak. Males had significantly higher resting BPV-low-frequency (LF) values compared to females and did not significantly change following exercise, whereas females had significantly increased BPV-LF values following acute maximal exercise. Although males and females exhibited a significant decrease in both HRV-LF and HRV-high frequency (HF) with exercise, females had significantly higher HRV-HF values following exercise. Males had a significantly higher HRV-LF/HF ratio at rest; however, both males and females significantly increased their HRV-LF/HF ratio following exercise. Pre-menopausal females exhibit a cardioprotective autonomic profile compared to age-matched males due to lower resting sympathetic activity and faster vagal reactivation following maximal exercise. Acute maximal exercise is a sufficient autonomic stressor to demonstrate sex differences in the critical post-exercise recovery period.
Full Text Available The incidence and severity of infections in childhood is typically greater in males. The basis for these observed sex differences is not well understood, and potentially may facilitate novel approaches to reducing disease from a range of conditions. We here investigated sex differences in HIV-infected children in relation to antiretroviral therapy (ART initiation and post-treatment outcome. In a South African cohort of 2,101 HIV-infected children, we observed that absolute CD4+ count and CD4% were significantly higher in ART-naïve female, compared to age-matched male, HIV-infected children. Absolute CD4 count and CD4% were also significantly higher in HIV-uninfected female versus male neonates. We next showed that significantly more male than female children were initiated on ART (47% female; and children not meeting criteria to start ART by >5 yrs were more frequently female (59%; p<0.001. Among ART-treated children, immune reconstitution of CD4 T-cells was more rapid and more complete in female children, even after adjustment for pre-ART absolute CD4 count or CD4% (p=0.011, p=0.030, respectively. However, while ART was initiated as a result of meeting CD4 criteria less often in females (45%, ART initiation as a result of clinical disease in children whose CD4 counts were above treatment thresholds occurred more often in females (57%, p<0.001. The main sex difference in morbidity observed in children initiating ART above CD4 thresholds, above that of TB disease, was as a result of wasting and stunting observed in females with above-threshold CD4 counts (p=0.002. These findings suggest the possibility that optimal treatment of HIV-infected children might incorporate differential CD4 treatment thresholds for ART initiation according to sex.
Nicolella Daniel P
Full Text Available Abstract The occurrence of knee osteoarthritis (OA increases with age and is more common in women compared with men, especially after the age of 50 years. Recent work suggests that contact stress in the knee cartilage is a significant predictor of the risk for developing knee OA. Significant gaps in knowledge remain, however, as to how changes in musculoskeletal traits disturb the normal mechanical environment of the knee and contribute to sex differences in the initiation and progression of idiopathic knee OA. To illustrate this knowledge deficit, we summarize what is known about the influence of limb alignment, muscle function, and obesity on sex differences in knee OA. Observational data suggest that limb alignment can predict the development of radiographic signs of knee OA, potentially due to increased stresses and strains within the joint. However, these data do not indicate how limb alignment could contribute to sex differences in either the development or worsening of knee OA. Similarly, the strength of the knee extensor muscles is compromised in women who develop radiographic and symptomatic signs of knee OA, but the extent to which the decline in muscle function precedes the development of the disease is uncertain. Even less is known about how changes in muscle function might contribute to the worsening of knee OA. Conversely, obesity is a stronger predictor of developing knee OA symptoms in women than in men. The influence of obesity on developing knee OA symptoms is not associated with deviation in limb alignment, but BMI predicts the worsening of the symptoms only in individuals with neutral and valgus (knock-kneed knees. It is more likely, however, that obesity modulates OA through a combination of systemic effects, particularly an increase in inflammatory cytokines, and mechanical factors within the joint. The absence of strong associations of these surrogate measures of the mechanical environment in the knee joint with sex
Reyes-Aguilar, Azalea; Barrios, Fernando A
Evolutionary approaches have proposed that women possess an advantage over men in emotional functioning to promote attachment for child-rearing. Likewise, sex differences have been reported in traits such as personality and empathy, traits that likely modulate emotional processing. In this preliminary study, sex differences in emotional processing were analyzed, including empathy as a social emotion and personality traits, as well as whether there exist relationships between those measures. Young volunteers (N = 105) indicated the emotional valence, activation, and dominance that they experience in situations categorized as emotionally positive, negative, or neutral. The results of comparison between sexes supported the approach that women showed more sensitivity to high activation and dominance for positive emotions and empathy, and men were more sensitive to negative situations. Correlation analysis showed only one positive relationship between scores of Self-transcendence, a subscale of Temperament and Character Inventory, with activation scores of neutral situations, but not with emotionally charged situations, perhaps because emotions are context-dependent processes while personality traits are considered context-independent descriptions of habits. These findings should be replicated to enrich knowledge about problems in emotional processing. © The Author(s) 2016.
Bekker, Marrie H. J.; van Assen, Marcel A. L. M.
Objectives This study aimed to examine if autonomy-connectedness, capacity for self-governance under the condition of connectedness, would mediate sex differences in symptoms of various mental disorders (depression, anxiety, eating disorders, antisocial personality disorder). Method Participants (N = 5,525) from a representative community sample in the Netherlands filled out questionnaires regarding the variables under study. Results Autonomy-connectedness (self-awareness, SA; sensitivity to others, SO; capacity for managing new situations, CMNS) fully mediated the sex differences in depression and anxiety, and partly in eating disorder -(drive for thinness, bulimia, and body dissatisfaction) and anti-social personality disorder characteristics. The mediations followed the expected sex-specific patterns. SO related positively to the internalizing disorder indices, and negatively to the anti-social personality disorder. SA related negatively to all disorder indices; and CMNS to all internalizing disorder indices, but positively to the anti-social personality disorder. Conclusion Treatment of depression, anxiety, but also eating disorders and the antisocial personality disorder may benefit from a stronger focus on autonomy strengthening. PMID:28771498
Harper, Vernon B
Researchers have pointed to the influence of sex with respect to the attributes of the computer medium. The author elaborates upon possible sex differences in reference to perceived attributes of the computer medium, i.e., Richness, Accessibility, Velocity, Interactivity, Plasticity, and Immediacy. Data from both a pilot and main study are reported and interpreted. The pilot study included 78 participants, while the main study involved 211. The independent samples were composed of Communication Studies students enrolled at two Mid-Atlantic universities. Nine items with anchors of 1: strongly disagree and 7: strongly agree were taken from the 2000 Computer Mediated Communication Competence Scale of Spitzberg to assess the attributes of computer-mediated interaction. The results indicate that women scored higher than men on perceptions of Accessibility, Velocity, Interactivity, and Immediacy.
Jonathan Hill; Helen Sharp; Lynne Murray
Females are superior to males on a range of tasks indexing social sensitivity, the capacity to infer others' mental states and respond with appropriate behaviours and emotions(1-3). There are also sex differences in psychiatric disorders in children and adolescents. Boys have higher rates of psychiatric disorders before puberty, but disorders increase markedly in girls after puberty (4). The causes of the commonest forms of disorder, antisocial behaviour problems in boys, and depression ...
Ionescu, M D
Memory performance estimates of men and women before and after a recall test were investigated. College students (17 men and 20 women), all juniors, participated in a memory task involving the recall of 80 stimuli (40 pictures and 40 words). Before and after the task they were asked to provide estimates of their pre- and postrecall performance. Although no sex differences were found for total correct recall, recall for pictures, and recall for words, or in the estimates of memory performance before the recall task, there were significant differences after the test: women underestimated their performance on the words and men underestimated their performance on the picture items.
Cribbin, Kayla M; Quackenbush, Corey R; Taylor, Kyle; Arias-Rodriguez, Lenin; Kelley, Joanna L
The tropical gar (Atractosteus tropicus) is the southernmost species of the seven extant species of gar fishes in the world. In Mexico and Central America, the species is an important food source due to its nutritional quality and low price. Despite its regional importance and increasing concerns about overexploitation and habitat degradation, basic genetic information on the tropical gar is lacking. Determining genetic information on the tropical gar is important for the sustainable management of wild populations, implementation of best practices in aquaculture settings, evolutionary studies of ancient lineages, and an understanding of sex-specific gene expression. In this study, the transcriptome of the tropical gar was sequenced and assembled de novo using tissues from three males and three females using Illumina sequencing technology. Sex-specific and highly differentially expressed transcripts in brain and muscle tissues between adult males and females were subsequently identified. The transcriptome was assembled de novo resulting in 80,611 transcripts with a contig N50 of 3,355 base pairs and over 168 kilobases in total length. Male muscle, brain, and gonad as well as female muscle and brain were included in the assembly. The assembled transcriptome was annotated to identify the putative function of expressed transcripts using Trinotate and SwissProt, a database of well-annotated proteins. The brain and muscle datasets were then aligned to the assembled transcriptome to identify transcripts that were differentially expressed between males and females. The contrast between male and female brain identified 109 transcripts from 106 genes that were significantly differentially expressed. In the muscle comparison, 82 transcripts from 80 genes were identified with evidence for significant differential expression. Almost all genes identified as differentially expressed were sex-specific. The differentially expressed transcripts were enriched for genes involved in
Ramos-Loyo, Julieta; Angulo-Chavira, Armando; Llamas-Alonso, Luis A; González-Garrido, Andrés A
The aim of the present study was to explore sex differences in the effects that emotional contexts exert on the temporal course of response inhibition using event-related potentials (ERP). Participants performed a Go-NoGo response inhibition task under 3 context conditions: with 1) neutral background stimuli, and 2) pleasant, and 3) unpleasant emotional contexts. No sex differences were found in relation to accuracy. Women showed higher N2NoGo amplitudes than men in both emotional contexts; whereas during inhibition men tended to show higher P3NoGo amplitudes than women in the unpleasant context. Both groups experienced a relevant effect of the presence of the unpleasant context during inhibition processing, as shown by the enhancement of the N2NoGo amplitudes in frontal regions compared to results from the neutral and pleasant conditions. In addition, women showed differences between the pleasant and unpleasant contexts, with the latter inducing higher amplitude values. Only in men did inhibition accuracy correlate with higher N2NoGo and lower P3NoGo amplitudes in the emotional context conditions. These findings suggest that when an inhibition task is performed in an emotionally-neutral background context no sex differences are observed in either accuracy or ERP components. However, when the emotional context was introduced -especially the unpleasant one- some gender differences did become evident. The higher N2NoGo amplitude at the presence of the unpleasant context may reflect an effect on attention and conflict monitoring. In addition, results suggest that during earlier processing stages, women invested more resources to process inhibition than men. Furthermore, men who invested more neural resources during earlier stages showed better response inhibition than those who did it during later processing stages, more closely-related to cognitive and motor inhibition processes. Copyright © 2016 Elsevier Ltd. All rights reserved.
Agate, Robert J.; Grisham, William; Wade, Juli; Mann, Suzanne; Wingfield, John; Schanen, Carolyn; Palotie, Aarno; Arnold, Arthur P.
In mammals and birds, sex differences in brain function and disease are thought to derive exclusively from sex differences in gonadal hormone secretions. For example, testosterone in male mammals acts during fetal and neonatal life to cause masculine neural development. However, male and female brain cells also differ in genetic sex; thus, sex chromosome genes acting within cells could contribute to sex differences in cell function. We analyzed the sexual phenotype of the brain of a rare gyna...
Chen, Christina; Van Horn, John Darrell
Examining sex differences in the brain has been historically contentious but is nonetheless important for advancing mental health for both girls and boys. Unfortunately, females in biomedical research remain underrepresented in most mental health conditions including autism spectrum disorders (ASD), even though equal inclusion of females would improve treatment for girls and yield benefits to boys. This review examines sex differences in the relationship between neuroanatomy and neurogenetics of ASD. Recent findings reveal that girls diagnosed with ASD exhibit more intellectual and behavioral problems compared to their male counterparts, suggesting that girls may be less likely diagnosed in the absence of such problems or that they require a higher mutational load to meet the diagnostic criteria. Thus far, the female biased effect of chromosome 4, 5p15.33, 8p, 9p24.1, 11p12-13, 15q, and Xp22.3 and the male biased effect of 1p31.3, 5q12.3, 7q, 9q33.3, 11q13.4, 13q33.3, 16p11.2, 17q11-21, Xp22.33/Yp11.31, DRD1, NLGN3, MAOA, and SHANK1 deletion have been discovered in ASD. The SNPs of genes such as RYR2, UPP2, and the androgen receptor gene have been shown to have sex-biasing factors in both girls and boys diagnosed with ASD. These sex-related genetic factors may drive sex differences in the neuroanatomy of these girls and boys, including abnormal enlargement in temporal gray and white matter volumes, and atypical reduction in cerebellar gray matter volumes and corpus callosum fibers projecting to the anterior frontal cortex in ASD girls relative to boys. Such factors may also be responsible for the attenuation of brain sexual differentiation in adult men and women with ASD; however, much remains to be uncovered or replicated. Future research should leverage further the association between neuroanatomy and genetics in girls for an integrated and interdisciplinary understanding of ASD.
Franklin, Ruth M.; Dotger, Sharon
Abstinence sexuality education (sex ed) is the only federally funded sex ed in the United States. The strict curriculum of this education does not educate American adolescents about safer sex practices and leaves a knowledge gap in these adolescents that follows them into college. The Problem: This project aimed to identify sex knowledge…
Bos, Henny M W; Kuyper, Lisette; Gartrell, Nanette K
This investigation compared Dutch same-sex parent and different-sex parent households on children's psychological well-being, parenting stress, and support in child rearing. It was also assessed whether associations among children's well-being, parenting stress, and support in child rearing were different in the two household types. Data were based on a nationally representative survey (N = 25,250). Matching was used to enhance similarity in background characteristics between both types of families. Parental and child characteristics were matched for 43 female same-sex parent, 52 male same-sex parent, and 95 different-sex parent households with offspring between 5 and 18 years old. No significant differences were found on children's well-being, problems in the parent-child relationship, being worried about the child, or the use of formal and informal support between mothers in same-sex and different-sex parent households or for fathers in same-sex and different-sex parent households. Regarding perceived confidence in child rearing, fathers in same-sex parent households and mothers in different-sex parent households felt less competent than their counterparts. Neither the associations between children's well-being and the predictors (parenting stress variables) nor those between support and the predictors (parenting stress and children's well-being) differed along household type. In this population-based study, the similarity in child outcomes regardless of household type confirms the results of prior investigations based on convenience samples. These findings are pertinent to family therapists, practitioners, court officials, and policymakers who seek information on parenting experiences and child outcomes in female and male same-sex parent families. © 2017 Family Process Institute.
Latifpour, J.; Kondo, S.; O'Hollaren, B.; Morita, T.; Weiss, R.M.
As age and sex affect the function of the lower urinary tract, we studied the characteristics of adrenergic and cholinergic receptors in various parts of lower urinary tract smooth muscle of young (6 months) and old (4 1/2-5 years) male and female rabbits. Saturation experiments performed with [3H]prazosin, [3H]yohimbine, [3H]dihydroalprenolol and [3H]quinuclidinyl benzylate in rabbit bladder base, bladder dome and urethra indicate the presence of regional, sex- and age-related differences in the density of alpha-1, alpha-2, and beta adrenergic and muscarinic cholinergic receptors. Alpha-2 adrenergic receptor density is considerably higher in the female than in the male urethra of both age groups, whereas the higher density of beta adrenergic receptors in the female than in the male bladder base is observed only in the younger animals. The density of muscarinic receptors is higher in bladder dome than in bladder base or urethra in young rabbits of both sexes. In the old animals, the density of muscarinic receptors in bladder base increases to the level observed in bladder dome. Inhibition experiments with selective adrenergic agonists and antagonists indicate that the pharmacological profiles of alpha-2 adrenergic receptors in the urethra and beta adrenergic receptors in the bladder dome and bladder base are similar in both sexes and at both ages. Beta-2 adrenergic receptors are shown to be predominant in bladder base and bladder dome of rabbits. Parallel studies in rabbit urethra, adult rat cortex and neonatal rat lung show that the urethral alpha-2 adrenergic receptors are of the alpha-2A subtype
Aguayo, Antonio; Martin, Camille S; Huddy, Timothy F; Ogawa-Okada, Maya; Adkins, Jamie L; Steele, Andrew D
Recent studies in mice have demonstrated a sexual dimorphism in circadian entrainment to scheduled feeding. On a time restricted diet, males tend to develop food anticipatory activity (FAA) sooner than females and with a higher amplitude of activity. The underlying cause of this sex difference remains unknown. One study suggests that sex hormones, both androgens and estrogens, modulate food anticipatory activity in mice. Here we present results suggesting that the sex difference in FAA is unrelated to gonadal sex hormones. While a sex difference between males and females in FAA on a timed, calorie restricted diet was observed there were no differences between intact and gonadectomized mice in the onset or magnitude of FAA. To test other sources of the sex difference in circadian entrainment to scheduled feeding, we used sex chromosome copy number mutants, but there was no difference in FAA when comparing XX, XY-, XY-;Sry Tg, and XX;Sry Tg mice, demonstrating that gene dosage of sex chromosomes does not mediate the sex difference in FAA. Next, we masculinized female mice by treating them with 17-beta estradiol during the neonatal period; yet again, we saw no difference in FAA between control and masculinized females. Finally, we observed that there was no longer a sex difference in FAA for older mice, suggesting that the sex difference in FAA is age-dependent. Thus, our study demonstrates that singular manipulations of gonadal hormones, sex chromosomes, or developmental patterning are not able to explain the difference in FAA between young male and female mice.
Farré, J M; Fernández-Aranda, F; Granero, R; Aragay, N; Mallorquí-Bague, N; Ferrer, V; More, A; Bouman, W P; Arcelus, J; Savvidou, L G; Penelo, E; Aymamí, M N; Gómez-Peña, M; Gunnard, K; Romaguera, A; Menchón, J M; Vallès, V; Jiménez-Murcia, S
Recently, the DSM-5 has developed a new diagnostic category named "Substance-related and Addictive Disorders". This category includes gambling disorder (GD) as the sole behavioral addiction, but does not include sex addiction (SA). The aim of this study is to investigate whether SA should be classified more closely to other behavioral addictions, via a comparison of the personality characteristics and comorbid psychopathology of individuals with SA with those of individuals with GD, which comes under the category of addiction and related disorders. The sample included 59 patients diagnosed with SA, who were compared to 2190 individuals diagnosed with GD and to 93 healthy controls. Assessment measures included the Diagnostic Questionnaire for Pathological Gambling, the South Oaks Gambling Screen, the Symptom CheckList-90 Items-Revised and the Temperament and Character Inventory-Revised. No statistically significant differences were found between the two clinical groups, except for socio-economic status. Although statistically significant differences were found between both clinical groups and controls for all scales on the SCL-90, no differences were found between the two clinical groups. The results were different for personality characteristics: logistic regression models showed that sex addictive behavior was predicted by a higher education level and by lower scores for TCI-R novelty-seeking, harm avoidance, persistence and self-transcendence. Being employed and lower scores in cooperativeness also tended to predict the presence of sex addiction. While SA and GD share some psychopathological and personality traits that are not present in healthy controls, there are also some diagnostic-specific characteristics that differentiate between the two clinical groups. These findings may help to increase our knowledge of phenotypes existing in behavioral addictions. Copyright © 2014 Elsevier Inc. All rights reserved.
Full Text Available Eri Ito, Jun Iwamoto, Koichiro Azuma, Hideo MatsumotoInstitute for Integrated Sports Medicine, Keio University School of Medicine, Tokyo, JapanAbstract: The purpose of the present study was to investigate sex-specific differences in injury types among basketball players. According to our database, during the 20-year period between October 1991 and June 2011, 1,219 basketball players (640 males and 579 females consulted our sports medicine clinic; in total, 1,414 injuries in basketball players (729 injuries in males and 685 injuries in females were recorded. The mean age of patients was 19.6 years. The most common injury site was the knee, followed by the foot and ankle, lower back, and upper extremities. There was a higher proportion of female players presenting with a knee injury, compared with male players (50.4% vs 41.7%, and a lower proportion of female players presenting with an upper extremity injury (5.1% vs 9.7%. The proportion of anterior cruciate ligament injury in the 10–19-year-old age group was higher among female players than among male players (45.9% vs 22.1%, while the proportions of Osgood–Schlatter disease in the 10–19-year-old age group and jumper's knee (patellar and femoral tendinopathy in the 20–29-year-old age group were higher among male players than among female players (12.5% vs 1.8% and 14.6% vs 3.7%, respectively. However, the proportions of other injuries did not differ significantly between male and female players. The present observational study, which was performed using a retrospective case-series design, showed the existence of sex-specific differences in knee injuries sustained while participating in basketball.Keywords: sports injury, sex, anterior cruciate ligament injury, Osgood–Schlatter disease, basketball
Romberg, Kerstin; Tufvesson, Ellen; Bjermer, Leif
Elite athletes, independent of sport, have increased risk of developing asthma, but little is known about sex difference among adolescent athletes. To investigate and compare sex-related differences according to symptoms and treatment of asthma, allergy, and health among elite athletes and a reference group. Adolescent elite swimmers (n = 101), tennis players (n = 86), and a reference group (n = 1,628) responded to a questionnaire about respiratory symptoms, allergy, health behavior, psychosomatic symptoms, self- esteem, and well-being. The athletes performed a mannitol provocation and a sport-specific exercise provocation. Atopy was assessed by skin prick tests, and fractional exhaled nitric oxide was measured. The females reported more asthma symptoms than the males in both the reference group (29.1% vs 22.3%) and the athlete group (56.4% vs 40.2%). However, no significant differences were found in physician-diagnosed asthma or treatment with inhaled corticosteroids. More female athletes had a positive mannitol provocation result (48.7% vs 35.8% in male athletes), and more female swimmers had a positive exercise provocation result (15.1% vs 7.7% in male swimmers). The females in all groups had more psychosomatic symptoms compared with the respective males, and the males in the reference group reported higher self-esteem and felt more well-being compared with the reference group females. Overall, we found a higher prevalence of asthma symptoms in the females. However, the frequency of physician-diagnosed asthma and the prescription of inhaled corticosteroids were the same in both sexes. This finding demonstrates an insufficient diagnosis of asthma in females. Copyright © 2016 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.
Lee, Debbiesiu L; Harkless, Lynn E; Sheridan, Daniel J; Winakur, Emily; Fowers, Blaine J
Sexual orientation was examined as a moderator in the relation between biological sex and interpersonal problems. Participants were 60 lesbians, 45 heterosexual women, 37 gay men, and 39 heterosexual men, who completed the Inventory of Interpersonal Problems-Circumplex. Sexual orientation was found to moderate one of the eight interpersonal problems under study. Heterosexual women scored significantly higher than lesbian women in Non-assertive. Although hypothesized, gay men did not differ from heterosexual men along the Dominant-Cold quadrant. Implications of these results are discussed.
Li, Chiang-Shan R; Zhang, Sheng; Hung, Chia-Chun; Chen, Chun-Ming; Duann, Jeng-Ren; Lin, Ching-Po; Lee, Tony Szu-Hsien
Chronic ketamine use leads to cognitive and affective deficits including depression. Here, we examined sex differences and neural bases of depression in chronic ketamine users. Compared to non-drug using healthy controls (HC), ketamine-using females but not males showed increased depression score as assessed by the Center of Epidemiological Studies Depression Scale (CES-D). We evaluated resting state functional connectivity (rsFC) of the subgenual anterior cingulate cortex (sgACC), a prefrontal structure consistently implicated in the pathogenesis of depression. Compared to HC, ketamine users (KU) did not demonstrate significant changes in sgACC connectivities at a corrected threshold. However, in KU, a linear regression against CES-D score showed less sgACC connectivity to the orbitofrontal cortex (OFC) with increasing depression severity. Examined separately, male and female KU showed higher sgACC connectivity to bilateral superior temporal gyrus and dorsomedial prefrontal cortex (dmPFC), respectively, in correlation with depression. The linear correlation of sgACC-OFC and sgACC-dmPFC connectivity with depression was significantly different in slope between KU and HC. These findings highlighted changes in rsFC of the sgACC as associated with depression and sex differences in these changes in chronic ketamine users. Copyright © 2017 Elsevier B.V. All rights reserved.
Seifert, Hilary A; Benedek, Gil; Liang, Jian; Nguyen, Ha; Kent, Gail; Vandenbark, Arthur A; Saugstad, Julie A; Offner, Halina
Stroke is the leading cause of disability in the United States. Sex differences, including smaller infarcts in females and greater involvement of immune-mediated inflammation in males may affect the efficacy of immune-modulating interventions. To address these differences, we sought to identify distinct stroke-modifying mechanisms in female vs. male mice. The current study demonstrated smaller infarcts and increased levels of regulatory CD19 + CD5 + CD1d hi B10 cells as well as anti-inflammatory CD11b + CD206 + microglia/macrophages in the ipsilateral vs. contralateral hemisphere of female but not male mice undergoing 60min middle cerebral artery occlusion followed by 96h of reperfusion. Moreover, female mice with MCAO had increased total spleen cell numbers but lower B10 levels in spleens. These results elucidate differing sex-dependent regulatory mechanisms that account for diminished stroke severity in females and underscore the need to test immune-modulating therapies for stroke in both males and females. Copyright © 2017 Elsevier Inc. All rights reserved.
Julia Colette Berbesque
Full Text Available Food preferences are important for understanding foraging choices. In studying human foragers rather than other animals, we have the advantage of being able to ask them which foods they prefer. Yet surprisingly, no studies of systematically collected data exist on human forager food preferences. The Hadza of Tanzania are full-time foragers in an area where the hominin record extends back to 3-4 million years ago, so their diet is very relevant for understanding the paleo-diet. Here, we report on their food preferences, elicited with photographs of species within the five major food categories in their diet: honey, meat, berries, baobab, and tubers. There were sex differences in the ranks of two food categories: meat and berries. While male and female ranks agreed on the other three food categories, females ranked berries second and meat fourth, whereas males ranked meat second and berries fourth. Theses similarities and differences are interesting in light of the fact that the sexes target different foods. We discuss the implications of Hadza food preferences for the origin of the uniquely human sexual division of foraging labor.
Gard, Marja Germans; Kring, Ann M
Conventional wisdom holds that women are more "emotional" than men. However, research evidence suggests that sex differences in emotion are considerably more complex. The authors tested hypotheses about sex differences in the engagement of the approach and avoidance motivational systems thought to underpin emotional responses. The authors measured reported emotional experience and startle response magnitude both during the presentation and after the offset of emotional stimuli that engage these motivational systems to assess whether men and women differ in their patterns of immediate response to emotional stimuli and in their patterns of recovery from these responses. Our findings indicated that women were more experientially reactive to negative, but not positive, emotional pictures compared to men, and that women scored higher than men on measure of aversive motivational system sensitivity. Although both men and women exhibited potentiation of the startle response during the presentation of negative pictures relative to neutral pictures, only women continued to show this relative potentiation during the recovery period, indicating that women were continuing to engage the aversive motivational system after the offset of negative emotional pictures.
Girard-Tremblay, Lydia; Auclair, Vincent; Daigle, Kathya; Léonard, Guillaume; Whittingstall, Kevin; Goffaux, Philippe
Sex differences in pain perception are still poorly understood, but they may be related to the way the brains of men and women respond to the affective dimensions of pain. Using a matched pain intensity paradigm, where pain intensity was kept constant across participants but pain unpleasantness was left free to vary among participants, we studied the relationship between pain unpleasantness and pain-evoked brain activity in healthy men and women separately. Experimental pain was provoked using transcutaneous electrical stimulation of the sural nerve while pain-related brain activity was measured using somatosensory-evoked brain potentials with source localization. Cardiac responses to pain were also measured using electrocardiac recordings. Results revealed that subjective pain unpleasantness was strongly associated with increased perigenual anterior cingulate cortex activity in women, whereas it was strongly associated with decreased ventromedial prefrontal cortex activity in men. Only ventromedial prefrontal cortex deactivations in men were additionally associated with increased autonomic cardiac arousal. These results suggest that in order to deal with pain's objectionable properties, men preferentially deactivate prefrontal suppression regions, leading to the mobilization of threat-control circuits, whereas women recruit well-known emotion-processing areas of the brain. This article presents neuroimaging findings demonstrating that subjective pain unpleasantness ratings are associated with different pain-evoked brain responses in men and women, which has potentially important implications regarding sex differences in the risk of developing chronic pain. Copyright © 2014 American Pain Society. Published by Elsevier Inc. All rights reserved.
Dumais, Kelly M; Kulkarni, Praveen P; Ferris, Craig F; Veenema, Alexa H
The neuropeptide oxytocin (OT) regulates social behavior in sex-specific ways across species. OT has promising effects on alleviating social deficits in sex-biased neuropsychiatric disorders. However little is known about potential sexually dimorphic effects of OT on brain function. Using the rat as a model organism, we determined whether OT administered centrally or peripherally induces sex differences in brain activation. Functional magnetic resonance imaging was used to examine blood oxygen level-dependent (BOLD) signal intensity changes in the brains of awake rats during the 20min following intracerebroventricular (ICV; 1μg/5μl) or intraperitoneal (IP; 0.1mg/kg) OT administration as compared to baseline. ICV OT induced sex differences in BOLD activation in 26 out of 172 brain regions analyzed, with 20 regions showing a greater volume of activation in males (most notably the nucleus accumbens and insular cortex), and 6 regions showing a greater volume of activation in females (including the lateral and central amygdala). IP OT also elicited sex differences in BOLD activation with a greater volume of activation in males, but this activation was found in different and fewer (10) brain regions compared to ICV OT. In conclusion, exogenous OT modulates neural activation differently in male versus female rats with the pattern and magnitude, but not the direction, of sex differences depending on the route of administration. These findings highlight the need to include both sexes in basic and clinical studies to fully understand the role of OT on brain function. Copyright © 2017 Elsevier Ltd. All rights reserved.
Dumais, Kelly M; Veenema, Alexa H
The neuropeptides vasopressin (VP) and oxytocin (OT) and their receptors in the brain are involved in the regulation of various social behaviors and have emerged as drug targets for the treatment of social dysfunction in several sex-biased neuropsychiatric disorders. Sex differences in the VP and OT systems may therefore be implicated in sex-specific regulation of healthy as well as impaired social behaviors. We begin this review by highlighting the sex differences, or lack of sex differences, in VP and OT synthesis in the brain. We then discuss the evidence showing the presence or absence of sex differences in VP and OT receptors in rodents and humans, as well as showing new data of sexually dimorphic V1a receptor binding in the rat brain. Importantly, we find that there is lack of comprehensive analysis of sex differences in these systems in common laboratory species, and we find that, when sex differences are present, they are highly brain region- and species-specific. Interestingly, VP system parameters (VP and V1aR) are typically higher in males, while sex differences in the OT system are not always in the same direction, often showing higher OT expression in females, but higher OT receptor expression in males. Furthermore, VP and OT receptor systems show distinct and largely non-overlapping expression in the rodent brain, which may cause these receptors to have either complementary or opposing functional roles in the sex-specific regulation of social behavior. Though still in need of further research, we close by discussing how manipulations of the VP and OT systems have given important insights into the involvement of these neuropeptide systems in the sex-specific regulation of social behavior in rodents and humans. Copyright © 2015 Elsevier Inc. All rights reserved.
Dumais, Kelly M.; Veenema, Alexa H.
The neuropeptides vasopressin (VP) and oxytocin (OT) and their receptors in the brain are involved in the regulation of various social behaviors and have emerged as drug targets for the treatment of social dysfunction in several sex-biased neuropsychiatric disorders. Sex differences in the VP and OT systems may therefore be implicated in sex-specific regulation of healthy as well as impaired social behaviors. We begin this review by highlighting the sex differences, or lack of sex differences, in VP and OT synthesis in the brain. We then discuss the evidence showing the presence or absence of sex differences in VP and OT receptors in rodents and humans, as well as showing new data of sexually dimorphic V1a receptor binding in the rat brain. Importantly, we find that there is lack of comprehensive analysis of sex differences in these systems in common laboratory species, and we find that, when sex differences are present, they are highly brain region- and species- specific. Interestingly, VP system parameters (VP and V1aR) are typically higher in males, while sex differences in the OT system are not always in the same direction, often showing higher OT expression in females, but higher OT receptor expression in males. Furthermore, VP and OT receptor systems show distinct and largely non-overlapping expression in the rodent brain, which may cause these receptors to have either complementary or opposing functional roles in the sex-specific regulation of social behavior. Though still in need of further research, we close by discussing how manipulations of the VP and OT systems have given important insights into the involvement of these neuropeptide systems in the sex-specific regulation of social behavior in rodents and humans. PMID:25951955
Bozanic, Ana; Miletic, Durdica
The aims of this study were to determine possible differences between the sexes in specific rhythmic gymnastics techniques, and to examine the influence of various aspects of technique on rhythmic composition performance. Seventy-five students aged 21 ± 2 years (45 males, 30 female) undertook four test sessions to determine: coefficients of asymmetry, stability, versatility, and the two rhythmic compositions (without apparatus and with rope). An independent-sample t-test revealed sex-based differences in technique acquisition: stability for ball (P rhythmic composition without apparatus (P analysis revealed that the variables for assessing stability (beta = 0.44; P rhythmic composition performance of females, and the variables for assessing asymmetry (beta = -0.38; P rhythmic composition performance of males. The results suggest that female students dominate in body skill technique, while male students have the advantage with apparatus. There was a lack of an expressive aesthetic component in performance for males. The need for ambidexterity should be considered in the planning of training programmes.
Derry, Heather M; Padin, Avelina C; Kuo, Jennifer L; Hughes, Spenser; Kiecolt-Glaser, Janice K
Women become depressed more frequently than men, a consistent pattern across cultures. Inflammation plays a key role in initiating depression among a subset of individuals, and depression also has inflammatory consequences. Notably, women experience higher levels of inflammation and greater autoimmune disease risk compared to men. In the current review, we explore the bidirectional relationship between inflammation and depression and describe how this link may be particularly relevant for women. Compared to men, women may be more vulnerable to inflammation-induced mood and behavior changes. For example, transient elevations in inflammation prompt greater feelings of loneliness and social disconnection for women than for men, which can contribute to the onset of depression. Women also appear to be disproportionately affected by several factors that elevate inflammation, including prior depression, somatic symptomatology, interpersonal stressors, childhood adversity, obesity, and physical inactivity. Relationship distress and obesity, both of which elevate depression risk, are also more strongly tied to inflammation for women than for men. Taken together, these findings suggest that women's susceptibility to inflammation and its mood effects may contribute to sex differences in depression. Depression continues to be a leading cause of disability worldwide, with women experiencing greater risk than men. Due to the depression-inflammation connection, these patterns may promote additional health risks for women. Considering the impact of inflammation on women's mental health may foster a better understanding of sex differences in depression, as well as the selection of effective depression treatments.
Lu, Jing; Wu, Xue-Yan; Zhu, Qiong-Bin; Li, Jia; Shi, Li-Gen; Wu, Juan-Li; Zhang, Qi-Jun; Huang, Man-Li; Bao, Ai-Min
Sex differences play an important role in depression, the basis of which is an excessive stress response. We aimed at revealing the neurobiological sex differences in the same study in acute- and chronically-stressed rats. Female Sprague-Dawley (SD) rats were randomly divided into 6 groups: chronic unpredictable mild stress (CUMS), acute foot shock (FS) and controls, animals in all 3 groups were sacrificed in proestrus or diestrus. Male SD rats were randomly divided into 3 groups: CUMS, FS and controls. Comparisons were made of behavioral changes in CUMS and control rats, plasma levels of corticosterone (CORT), testosterone (T) and estradiol (E2), and of the hypothalamic mRNA-expression of stress-related molecules, i.e. estrogen receptor α and β, androgen receptor, aromatase, mineralocorticoid receptor, glucocorticoid receptor, corticotropin-releasing hormone, arginine vasopressin and oxytocin. CUMS resulted in disordered estrus cycles, more behavioral and hypothalamic stress-related molecules changes and a stronger CORT response in female rats compared with male rats. Female rats also showed decreased E2 and T levels after FS and CUMS, while male FS rats showed increased E2 and male CUMS rats showed decreased T levels. Stress affects the behavioral, endocrine and the molecular response of the stress systems in the hypothalamus of SD rats in a clear sexual dimorphic way, which has parallels in human data on stress and depression. Copyright © 2015 Elsevier B.V. All rights reserved.
Kogachi, Shannon; Chang, Linda; Alicata, Daniel; Cunningham, Eric; Ernst, Thomas
Methamphetamine (METH) is an addictive stimulant, and METH users have abnormal brain structures and function. The aims of this study were to investigate the relationships between impulsivity, brain structures, and possible sex-specific differences between METH users and non-drug using Controls. Structural MRI and the Barratt Impulsiveness Scale (BIS) questionnaire were completed in 124 subjects: 62 METH (ages 41.2 ± 1.4 years, 34 males) and 62 Controls (ages 43.3 ± 2.3 years, 36 males). Independent and interactive effects of METH use status and sex were evaluated. Relationships between METH usage characteristics, brain morphometry, and impulsivity scores were examined. METH users had higher impulsivity scores, on both the Cognitive and Behavioral Factors from the BIS (p impulsivity (interaction-p ≤ 0.05). Only female METH users showed relatively larger nucleus accumbens (interaction-p = 0.03). Greater impulsivity and thinner frontal cortices in METH users are validated. Larger superior frontal cortex in male METH users with greater cognitive impulsivity suggest decreased dendritic pruning during adolescence might have contributed to their impulsive and drug use behaviors. In the female METH users, smaller frontal cortices and the associated greater impulsivity suggest greater neurotoxicity to these brain regions, while their relatively larger nucleus accumbens suggest an estrogen-mediated neuroprotective glial response. Men and women may be affected differently by METH use.
Mikosz, Marta; Nowak, Aleksandra; Werka, Tomasz; Knapska, Ewelina
In its simplest form, empathy can be characterized as the capacity to share the emotional experiences among individuals, a phenomenon known as emotional contagion. Recent research shows that emotional contagion and its adaptive role can be studied in rodents. However, it is not known whether sex differences observed in human empathy extend to its more primitive forms. In the present study, we used a rat model of emotional contagion to compare the behavioral consequences of social transfer of information about threat, and the subsequent neural activation patterns in male and female rats. We found that: (1) males and females display a similar behavioral pattern during the interaction with either a fear-conditioned or a control rat; (2) interaction with a fear-conditioned conspecific positively modulates two-way avoidance learning in male and diestral female rats but not in estral females; and (3) such interaction results in increased c-Fos expression in the central and lateral nuclei of the amygdala and the prelimbic and infralimbic cortex in males, whereas in females no such changes were observed. Collectively, our results point to the occurrence of sex and estrus cycle phase differences in susceptibility to emotional contagion and underlying neuronal activation in rodents.
Jaime W. Thomson; Shilpa Patel; Steven M. Platek; Todd K. Shackelford
Sex differences in reaction to a romantic partner's infidelity are well documented and are hypothesized to be attributable to sex-specific jealousy mechanisms that solve sex specific adaptive problems. There have been few cognitive-based investigations of jealousy, however. Here we investigated sex differences in implicit processing of jealousy-based information. In Experiment 1, we used the implicit association test (IAT) to investigate sex-differentiated biases in classifying sexual or emot...
Lippa, Richard A
Analyzing a large international data set generated by a BBC Internet survey, I examined sex differences and sexual orientation differences in six personality traits: extraversion, agreeableness, neuroticism, disagreeable assertiveness, masculine versus feminine occupational preferences (MF-Occ), and self-ascribed masculinity-femininity (Self-MF). Consistent with previous research, sex differences and sexual orientation differences were largest for MF-Occ and for Self-MF. In general, heterosexual-homosexual differences mirrored sex differences in personality, with gay men shifted in female-typical and lesbians in male-typical directions. Bisexual men scored intermediate between heterosexual and gay men on MF-Occ; however, they were slightly more feminine than gay men on Self-MF. Bisexual women scored intermediate between heterosexual women and lesbians on both MF-Occ and Self-MF. Sex differences and sexual orientation differences in MF-Occ, Self-MF, and other personality traits were consistent across five nations/world regions (the UK, USA, Canada, Australia/New Zealand, and Western Europe), thereby suggesting a biological component to these differences.
Full Text Available There are important sex differences in the brain that seem to arise from biology as well as psychosocial influences. Sex differences in several aspects of human behavior and cognition have been reported. Gonadal sex steroids or genes found on sex chromosomes influence sex differences in neuroanatomy, neurochemistry and neuronal structure, and connectivity. There has been some resistance to accept that sex differences in the human brain exist and have biological relevance; however, a few years ago, it has been recommended by the USA National Institute of Mental Health to incorporate sex as a variable in experimental and clinical neurological and psychiatric studies. We here review the clinical literature on sex differences in pain and neurological and psychiatric diseases, with the aim to further stimulate interest in sexual dimorphisms in the brain and brain diseases, possibly encouraging more research in the field of the implications of sex differences for treating these conditions.
Lane, A D; Yan, H; Ranadive, S M; Kappus, R M; Sun, P; Cook, M D; Harvey, I; Woods, J; Wilund, K; Fernhall, B
Ventricular and vascular coupling is defined as the ratio of arterial elastance (Ea) to ventricular elastance (Elv) and describes the interaction between the heart and arterial system. There are sex differences in both arterial and ventricular function in response to both acute exercise and aerobic exercise training. To examine the effects of aerobic exercise training on elastances and the coupling ratio in young adult men and women. We hypothesized a reduction in the coupling ratio in both sexes due to a decrease in Ea that would be more pronounced in men and an increase in Elv that would be larger in women. Fifty-three healthy, young adults completed the study. Central pulse wave velocity and heart volumes were measured before and after an 8-week aerobic training intervention. Elastances were calculated as Ea = end-systolic pressure/stroke volume and Elv = end-systolic pressure/end-systolic volume and indexed to body surface area. After the intervention, women augmented indexed and un-indexed Elv from 2.09 ± 0.61 to 2.52 ± 0.80 mmHg/ml, p 0.05). Women also reduced end-systolic pressure (from 91 ± 10 to 87 ± 10 mmHg), and both groups reduced central pulse wave velocity (from 6.0 ± 1.0 to 5.6 ± 0.6 m/s, p < 0.05). We conclude that after 8 weeks of aerobic training, only women reduced their coupling ratio due to an increase in Elv. This suggests that aerobic exercise training elicits sex-dependent changes in the coupling ratio in young, healthy individuals.
Berbesque, J Colette; Marlowe, Frank W; Pawn, Ian; Thompson, Peter; Johnson, Guy; Mabulla, Audax
Among hunter-gatherers, the sharing of male and female foods is often assumed to result in virtually the same diet for males and females. Although food sharing is widespread among the hunting and gathering Hadza of Tanzania, women were observed eating significantly more tubers than men. This study investigates the relationship between patterns of dental wear, diet, and extramasticatory use of teeth among the Hadza. Casts of the upper dentitions were made from molds taken from 126 adults and scored according to the Murphy dental attrition scoring system. Females had significantly greater anterior occlusal wear than males when we controlled for age. Males exhibited greater asymmetry in wear, with greater wear on the left side in canines, first premolars, and first molars. We suggest that these sex differences in wear patterns reflect the differences seen in the diet, as well as in the use of teeth as tools.
Colby, Sarah; Zhou, Wenjun; Sowers, Morgan F; Shelnutt, Karla; Olfert, Melissa D; Morrell, Jesse; Koenings, Mallory; Kidd, Tandalayo; Horacek, Tanya M; Greene, Geoffrey W; Brown, Onikia; White, Adrienne A; Hoerr, Sharon L; Byrd-Bredbenner, Carol; Kattelmann, Kendra K
The study purpose was to identify clusters of weight-related behaviors by sex in a college student populations. We conducted secondary data analysis from online surveys and physical assessments collected in Project Young Adults Eating and Active for Health (YEAH) with a convenience sample of students on 13 college campuses in the United States. We performed 2-step cluster analysis by sex to identify subgroups with homogeneous characteristics and behaviors. We used 8 derivation variables: healthy eating; eating restraints; external cues; stress; fruit/vegetable intake; calories from fat; calories from sugar-sweetened beverages; and physical activity. Contribution of derivation variables to clusters was analyzed with a MANOVA test. Data from 1594 students were included. Cluster analysis revealed 2-clusters labeled "Healthful Behavior" and "At-risk" for males and females with an additional "Laid Back" cluster for males. "At-risk" clusters had the highest BMI, waist circumference, elevated health risk, and stress and least healthy dietary intake and physical activity. The "Laid Back" cluster had normal weights and the lowest restrained eating, external cues sensitivity, and stress. Identified differences in characteristics and attitudes towards weight-related behaviors between males and females can be used to tailor weight management programs.
Meana, Marta; Nunnink, Sarah E
This study compared 220 college men and 237 college women on two types of self-reported cognitive distraction during sex, performance- and appearance-based. Affect, psychological distress, sexual knowledge, attitudes, fantasies, experiences, body image, satisfaction, and sexual function were assessed with the Derogatis Sexual Functioning Inventory and the Sexual History Form to determine associations with distraction. Between-gender analyses revealed that women reported higher levels of overall and appearance-based distraction than did men, but similar levels of performance-based distraction. Within-gender analyses revealed that women reported as much of one type of distraction as the other, while men reported more performance- than appearance-based distraction. In women, appearance-based distraction was predicted by negative body image, psychological distress, and not being in a relationship, while performance-based distraction was predicted by negative body image, psychological distress, and sexual dissatisfaction. In men, appearance-based distraction was predicted by negative body image, sexual dissatisfaction and not being in a relationship, while performance-based distraction was predicted by negative body image and sexual dissatisfaction. Investigating the content of cognitive distraction may be useful in understanding gender differences in sexual experience and in refining cognitive components of sex therapy.
Calkins, Monica E.; Ray, Amrita; Gur, Ruben C.; Freedman, Robert; Green, Michael F.; Greenwood, Tiffany A.; Light, Gregory A.; Nuechterlein, Keith H.; Olincy, Ann; Radant, Allen D.; Seidman, Larry J.; Siever, Larry J.; Silverman, Jeremy M.; Stone, William S.; Sugar, Catherine; Swerdlow, Neal R.; Tsuang, Debby W.; Tsuang, Ming T.; Turetsky, Bruce I.; Braff, David L.; Lazzeroni, Laura C.; Gur, Raquel E.
Background Numerous studies have documented that patients with schizophrenia show neurocognitive impairments, which are also heritable in schizophrenia families. In view of these findings, the current investigation tested the hypothesis that neurocognitive performance of schizophrenia probands can predict the neurocognitive performance of their unaffected family members. Methods Participants (n=1,967; schizophrenia=369; first-degree relatives=1,072; community comparison subjects=526) in the Consortium on the Genetics of Schizophrenia (COGS) were administered the Penn Computerized Neurocognitive Battery (CNB). Results Consistent with prior work, probands showed significant neurocognitive impairment, and neurocognitive ability was significantly heritable, across domains. On average, unaffected relatives did not differ from community comparison subjects in their neurocognitive performance. However, in 6 of 7 domains, probands’ score predicted the performance of their unaffected siblings. Male, but not female, probands’ performance was predictive of their unaffected relatives (siblings and mothers) performance, most consistently in face memory and spatial processing. Conclusions Using a novel approach in which individual probands are paired with their respective unaffected relatives within each family, we found that male probands’ performance predicted both sister and brother performance, an effect that was most powerfully observed for face memory and spatial processing. Results suggest that the familial transmission of sexually dimorphic neurocognitive domains, in which a particular sex tends to show a performance advantage over the other, may not itself be sex specific in schizophrenia families. PMID:23395246
Calkins, Monica E; Ray, Amrita; Gur, Ruben C; Freedman, Robert; Green, Michael F; Greenwood, Tiffany A; Light, Gregory A; Nuechterlein, Keith H; Olincy, Ann; Radant, Allen D; Seidman, Larry J; Siever, Larry J; Silverman, Jeremy M; Stone, William S; Sugar, Catherine; Swerdlow, Neal R; Tsuang, Debby W; Tsuang, Ming T; Turetsky, Bruce I; Braff, David L; Lazzeroni, Laura C; Gur, Raquel E
Numerous studies have documented that patients with schizophrenia show neurocognitive impairments, which are also heritable in schizophrenia families. In view of these findings, the current investigation tested the hypothesis that neurocognitive performance of schizophrenia probands can predict the neurocognitive performance of their unaffected family members. Participants (n=1967; schizophrenia=369; first-degree relatives=1072; community comparison subjects=526) in the Consortium on the Genetics of Schizophrenia were administered the Penn Computerized Neurocognitive Battery. Consistent with prior work, probands showed significant neurocognitive impairment, and neurocognitive ability was significantly heritable across domains. On average, unaffected relatives did not differ from community comparison subjects in their neurocognitive performance. However, in six of seven domains, proband scores predicted the performance of their unaffected siblings. Male, but not female, proband performance was predictive of their unaffected relatives' (siblings and mothers) performance, most consistently in face memory and spatial processing. Using a novel approach in which individual probands are paired with their respective unaffected relatives within each family, we found that male proband performance predicted both sister and brother performance, an effect that was most powerfully observed for face memory and spatial processing. Results suggest that the familial transmission of sexually dimorphic neurocognitive domains, in which a particular sex tends to show a performance advantage over the other, may not itself be sex specific in schizophrenia families. Copyright © 2013 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.
Full Text Available Purpose. Female runners are known to be at greater risk from chronic running injuries than age-matched males, although the exact mechanisms are often poorly understood. The aim of the current investigation was to determine if female recreational runners exhibit distinct limb and joint stiffness characteristics in relation to their male counterparts. Methods. Fourteen male and fourteen female runners ran over a force platform at 4.0 m · s-1. Lower limb kinematics were collected using an eight-camera optoelectric motion capture system operating at 250 Hz. Measures of limb and joint stiffness were calculated as a function of limb length and joint moments divided by the extent of limb and joint excursion. All stiffness and joint moment parameters were normalized to body mass. Sex differences in normalized limb and knee and ankle joint stiffness were examined statistically using independent samples t tests. Results. The results indicate that normalized limb (male = 0.18 ± 0.07, female = 0.37 ± 0.10 kN · kg · m-1 and knee stiffness (male = 5.59 ± 2.02, female = 7.34 ± 1.78 Nm · kg · rad-1 were significantly greater in female runners. Conclusions. On the basis that normalized knee and limb stiffness were shown to be significantly greater in female runners, the findings from the current investigation may provide further insight into the aetiology of the distinct injury patterns observed between sexes.
Giltay, E.J.; Kho, K.H.; Blansjaar, B.A.; Verbeek, M.M.; Geurtz, P.B.; Geleijnse, J.M.; Gooren, L.J.G.
There is a close relationship between the brain and the endocrine system. The brain expresses receptors for sex steroids and is capable of metabolizing these hormones. We explored (1) sex differences in homovanillic acid (HVA), a metabolite of the neurotransmitter dopamine, and (2) the effects of
Giltay, E.J.; Kho, King H.; Blansjaar, B.A.; Verbeek, M.M.; Geurtz, P.B.H.; Geleijnse, J.M.
There is a close relationship between the brain and the endocrine system. The brain expresses receptors for sex steroids and is capable of metabolizing these hormones. We explored (1) sex differences in homovanillic acid (HVA), a metabolite of the neurotransmitter dopamine, and (2) the effects of
Ito, Eri; Iwamoto, Jun; Azuma, Koichiro; Matsumoto, Hideo
The purpose of the present study was to investigate sex-specific differences in injury types among basketball players. According to our database, during the 20-year period between October 1991 and June 2011, 1,219 basketball players (640 males and 579 females) consulted our sports medicine clinic; in total, 1,414 injuries in basketball players (729 injuries in males and 685 injuries in females) were recorded. The mean age of patients was 19.6 years. The most common injury site was the knee, followed by the foot and ankle, lower back, and upper extremities. There was a higher proportion of female players presenting with a knee injury, compared with male players (50.4% vs 41.7%), and a lower proportion of female players presenting with an upper extremity injury (5.1% vs 9.7%). The proportion of anterior cruciate ligament injury in the 10-19-year-old age group was higher among female players than among male players (45.9% vs 22.1%), while the proportions of Osgood-Schlatter disease in the 10-19-year-old age group and jumper's knee (patellar and femoral tendinopathy) in the 20-29-year-old age group were higher among male players than among female players (12.5% vs 1.8% and 14.6% vs 3.7%, respectively). However, the proportions of other injuries did not differ significantly between male and female players. The present observational study, which was performed using a retrospective case-series design, showed the existence of sex-specific differences in knee injuries sustained while participating in basketball.
Bimonte, H A; Denenberg, V H
We investigated sex differences in VTE behavior in rats during radial arm maze learning. Females made more VTEs than males, although there were no sex differences in learning. Further, VTEs and errors were positively correlated during the latter testing sessions in females, but not in males. This sex difference may be a reflection of differences between the sexes in conflict behavior or cognitive strategy while solving the maze.
Koh, Sukjin; Gordon, Andrew S; Wienberg, Christopher; Sood, Sara O; Morley, Stephanie
Background Research on cerebral stroke symptoms using hospital records has reported that women experience more nontraditional symptoms of stroke (eg, mental status change, pain) than men do. This is an important issue because nontraditional symptoms may delay the decision to get medical assistance and increase the difficulty of correct diagnosis. In the present study, we investigate sex differences in the stroke experience as described in stories on weblogs. Objective The goal of this study was to investigate the feasibility of using the Internet as a source of data for basic research on stroke experiences. Methods Stroke experiences described in blogs were identified by using StoryUpgrade, a program that searches blog posts using a fictional prototype story. In this study, the prototype story was a description of a stroke experience. Retrieved stories coded by the researchers as relevant were used to update the search query and retrieve more stories using relevance feedback. Stories were coded for first- or third-person narrator, traditional and nontraditional patient symptoms, type of stroke, patient sex and age, delay before seeking medical assistance, and delay at hospital and in treatment. Results There were 191 relevant stroke stories of which 174 stories reported symptoms (52.3% female and 47.7% male patients). There were no sex differences for each traditional or nontraditional stroke symptom by chi-square analysis (all Ps>.05). Type of narrator, however, affected report of traditional and nontraditional symptoms. Female first-person narrators (ie, the patient) were more likely to report mental status change (56.3%, 27/48) than male first-person narrators (36.4%, 16/44), a marginally significant effect by logistic regression (P=.056), whereas reports of third-person narrators did not differ for women (27.9%, 12/43) and men (28.2%, 11/39) patients. There were more reports of at least 1 nontraditional symptom in the 92 first-person reports (44.6%, 41/92) than
Koh, Sukjin; Gordon, Andrew S; Wienberg, Christopher; Sood, Sara O; Morley, Stephanie; Burke, Deborah M
Research on cerebral stroke symptoms using hospital records has reported that women experience more nontraditional symptoms of stroke (eg, mental status change, pain) than men do. This is an important issue because nontraditional symptoms may delay the decision to get medical assistance and increase the difficulty of correct diagnosis. In the present study, we investigate sex differences in the stroke experience as described in stories on weblogs. The goal of this study was to investigate the feasibility of using the Internet as a source of data for basic research on stroke experiences. Stroke experiences described in blogs were identified by using StoryUpgrade, a program that searches blog posts using a fictional prototype story. In this study, the prototype story was a description of a stroke experience. Retrieved stories coded by the researchers as relevant were used to update the search query and retrieve more stories using relevance feedback. Stories were coded for first- or third-person narrator, traditional and nontraditional patient symptoms, type of stroke, patient sex and age, delay before seeking medical assistance, and delay at hospital and in treatment. There were 191 relevant stroke stories of which 174 stories reported symptoms (52.3% female and 47.7% male patients). There were no sex differences for each traditional or nontraditional stroke symptom by chi-square analysis (all Ps>.05). Type of narrator, however, affected report of traditional and nontraditional symptoms. Female first-person narrators (ie, the patient) were more likely to report mental status change (56.3%, 27/48) than male first-person narrators (36.4%, 16/44), a marginally significant effect by logistic regression (P=.056), whereas reports of third-person narrators did not differ for women (27.9%, 12/43) and men (28.2%, 11/39) patients. There were more reports of at least 1 nontraditional symptom in the 92 first-person reports (44.6%, 41/92) than in the 82 third-person reports (25
Cote, Anita T; Phillips, Aaron A; Foulds, Heather J; Charlesworth, Sarah A; Bredin, Shannon S D; Burr, Jamie F; Koehle, Michael S; Warburton, Darren E R
To evaluate sex differences in left ventricular (LV) function after an ultramarathon, and the association of vascular and training indices with the magnitude of exercise-induced cardiac fatigue. Descriptive field study. Fat Dog 100 Ultramarathon Trail Race, Canada. Thirty-four (13 women) recreational runners (aged 28-56 years). A 100-km or 160-km mountain marathon. Baseline baroreceptor sensitivity, heart rate variability, and arterial compliance; Pre-exercise and postexercise echocardiographic evaluations of LV dimensions, volumes, Doppler flow velocities, tissue velocities, strain, and strain rate. Finishers represented 17 men (44.8 ± 6.6 years) and 8 women (45.9 ± 10.2 years; P = 0.758). After ultraendurance exercise, significant reductions (P training status/experience. These findings suggest that vascular health is an important contributor to the degree of cardiovascular strain incurred as the result of an acute bout of prolonged strenuous exercise.
Humor operates through a variety of techniques, which first generate surprise and then amusement and laughter once the unexpected incongruity is resolved. As different types of jokes use different techniques, the corresponding humor processes also differ. The present study builds on the framework of the 'tri-component theory of humor,' which details the mechanisms involved in cognition (comprehension), affect (appreciation), and laughter (expression). This study seeks to identify differences among joke types and between sexes/genders in the neural mechanisms underlying humor processing. Three types of verbal jokes, bridging-inference jokes (BJs), exaggeration jokes (EJs), and ambiguity jokes (AJs), were used as stimuli. The findings revealed differences in brain activity for an interaction between sex/gender and joke type. For BJs, women displayed greater activation in the temporoparietal-mesocortical-motor network than men, demonstrating the importance of the temporoparietal junction (TPJ) presumably for 'theory of mind' processing, the orbitofrontal cortex for motivational functions and reward coding, and the supplementary motor area for laughter. Women also showed greater activation than men in the frontal-mesolimbic network associated with EJs, including the anterior (frontopolar) prefrontal cortex (aPFC, BA 10) for executive control processes, and the amygdala and midbrain for reward anticipation and salience processes. Conversely, AJs elicited greater activation in men than women in the frontal-paralimbic network, including the dorsal prefrontal cortex (dPFC) and parahippocampal gyrus. All joke types elicited greater activation in the aPFC of women than of men, whereas men showed greater activation than women in the dPFC. To confirm the findings related to sex/gender differences, random group analysis and within group variance analysis were also performed. These findings help further establish the mechanisms underlying the processing of different joke types
Full Text Available Humor operates through a variety of techniques, which first generate surprise and then amusement and laughter once the unexpected incongruity is resolved. As different types of jokes use different techniques, the corresponding humor processes also differ. The present study builds on the framework of the ‘tri-component theory of humor’, which details the mechanisms involved in cognition (comprehension, affect (appreciation, and laughter (expression. This study seeks to identify differences among joke types and between sexes/genders in the neural mechanisms underlying humor processing. Three types of verbal jokes, bridging-inference jokes (BJs, exaggeration jokes (EJs, and ambiguity jokes (AJs, were used as stimuli. The findings revealed differences in brain activity for an interaction between sex/gender and joke type. For BJs, women displayed greater activation in the temporoparietal-mesocortical-motor network than men, demonstrating the importance of the temporoparietal junction (TPJ presumably for ‘theory of mind’ processing, the orbitofrontal cortex for motivational functions and reward coding, and the supplementary motor area for laughter. Women also showed greater activation than men in the frontal-mesolimbic network associated with EJs, including the anterior (frontopolar prefrontal cortex (aPFC, BA 10 for executive control processes, and the amygdala and midbrain for reward anticipation and salience processes. Conversely, AJs elicited greater activation in men than women in the frontal-paralimbic network, including the dorsal prefrontal cortex (dPFC and parahippocampal gyrus. All joke types elicited greater activation in the aPFC of women than of men, whereas men showed greater activation than women in the dPFC. To confirm the findings related to sex/gender differences, random group analysis and within group variance analysis were also performed. These findings help further establish the mechanisms underlying the processing of
This article interprets technical communication research about sex differences according to social role theory, which argues that sex differences are enculturated through experiences associated with social positions in the family and the workplace. It reevaluates technical communication research about sex differences in communicative and…
Vigil's socio-relational framework of sex differences in emotional expressiveness emphasizes general sex differences in emotional responding, but largely ignores the social context in which emotions are expressed. There is much empirical evidence showing that sex differences in emotion displays are
Sommer, Iris E.; Aleman, Andre; Somers, Metten; Boks, Marco P.; Kahn, Rene S.
Many studies have investigated sex differences in language lateralization. Despite the large number of investigations, controversy about the presence of sex differences in lateralization remains. This study aims to provide a complete overview of sex differences in several reflections of language
Knechtle, Beat; Nikolaidis, Pantelis Theodoros; Stiefel, Michael; Rosemann, Thomas; Rüst, Christoph Alexander
The performance and sex differences of long-distance triathletes competing in 'Ironman Hawaii' are well investigated. However, less information is available with regards to triathlon races of the Ironman distance held under extreme environmental conditions (e.g. extreme cold) such as the 'Isklar Norseman Xtreme Triathlon' which started in 2003. In 'Isklar Norseman Xtreme Triathlon', athletes swim at a water temperature of ~13-15°C, cycle at temperatures of ~5-20°C and run at temperatures of ~12-28°C in the valley and of ~2-12°C at Mt. Gaustatoppen. This study analysed the performance trends and sex differences in 'Isklar Norseman Xtreme Triathlon' held from 2003 to 2015 using mixed-effects regression analyses. During this period, a total of 175 women (10.6%) and 1,852 men (89.4%) successfully finished the race. The number of female (r² = 0.53, P = 0.0049) and male (r² = 0.37, P = 0.0271) finishers increased and the men-to-women ratio decreased (r² = 0.86, P 0.05). Across years, women improved in swimming and both women and men improved in cycling and in overall race time (P 0.05). In summary, in 'Isklar Norseman Xtreme Triathlon' from 2003 to 2015, the number of successful women increased across years, women achieved a similar performance to men in swimming, cycling and overall race time, and women improved across years in swimming, cycling and overall race time.
Kogachi, Shannon; Chang, Linda; Alicata, Daniel; Cunningham, Eric; Ernst, Thomas
Methamphetamine (METH) is an addictive stimulant, and METH users have abnormal brain structures and function. The aims of this study were to investigate the relationships between impulsivity, brain structures, and possible sex-specific differences between METH users and non-drug using Controls. Structural MRI and the Barratt Impulsiveness Scale (BIS) questionnaire were completed in 124 subjects: 62 METH (ages 41.2 ± 1.4 years, 34 males) and 62 Controls (ages 43.3 ± 2.3 years, 36 males). Independent and interactive effects of METH use status and sex were evaluated. Relationships between METH usage characteristics, brain morphometry, and impulsivity scores were examined. METH users had higher impulsivity scores, on both the Cognitive and Behavioral Factors from the BIS (p users had larger, while female METH users had smaller, right superior frontal cortex (interaction-p = 0.0005). The male METH users with larger frontal volumes and female METH users with smaller or thinner frontal cortices had greater Cognitive impulsivity (interaction-p ≤ 0.05). Only female METH users showed relatively larger nucleus accumbens (interaction-p = 0.03). Greater impulsivity and thinner frontal cortices in METH users are validated. Larger superior frontal cortex in male METH users with greater cognitive impulsivity suggest decreased dendritic pruning during adolescence might have contributed to their impulsive and drug use behaviors. In the female METH users, smaller frontal cortices and the associated greater impulsivity suggest greater neurotoxicity to these brain regions, while their relatively larger nucleus accumbens suggest an estrogen-mediated neuroprotective glial response. Men and women may be affected differently by METH use. PMID:27095357
During recent decades numerous feminist scholars have scrutinized the two-sex model and questioned its status in Western societies and medicine. Along the same line, increased attention has been paid to individuals' experiences of atypical sex development, also known as intersex or 'disorders of sex development' (DSD). Yet research on individuals' experiences of finding out about their atypical sex development in adolescence has been scarce. Against this backdrop, the present article analyses 23 in-depth interviews with women who in their teens found out about their atypical sex development. The interviews were conducted during 2009-2012 and the interviewees were all Swedish. Drawing on feminist research on female embodiment and social scientific studies on diagnosis, I examine how the women make sense of their bodies and situations. First, I aim to explore how the women construe normality as they negotiate female embodiment. Second, I aim to investigate how the divergent manners in which these negotiations are expressed can be further understood via the women's different access to a diagnosis. Through a thematic and interpretative analysis, I outline two negotiation strategies: the "differently normal" and the "normally different" strategy. In the former, the women present themselves as just slightly different from 'normal' women. In the latter, they stress that everyone is different in some manner and thereby claim normalcy. The analysis shows that access to diagnosis corresponds to the ways in which the women present themselves as "differently normal" and "normally different", thus shedding light on the complex role of diagnosis in their negotiations of female embodiment. It also reveals that the women make use of what they do have and how alignments with and work on norms interplay as normality is construed. Copyright © 2013 Elsevier Ltd. All rights reserved.
Canli, Turhan; Desmond, John E; Zhao, Zuo; Gabrieli, John D E
Psychological studies have found better memory in women than men for emotional events, but the neural basis for this difference is unknown. We used event-related functional MRI to assess whether sex differences in memory for emotional stimuli is associated with activation of different neural systems in men and women. Brain activation in 12 men and 12 women was recorded while they rated their experience of emotional arousal in response to neutral and emotionally negative pictures. In a recognition memory test 3 weeks after scanning, highly emotional pictures were remembered best, and remembered better by women than by men. Men and women activated different neural circuits to encode stimuli effectively into memory even when the analysis was restricted to pictures rated equally arousing by both groups. Men activated significantly more structures than women in a network that included the right amygdala, whereas women activated significantly fewer structures in a network that included the left amygdala. Women had significantly more brain regions where activation correlated with both ongoing evaluation of emotional experience and with subsequent memory for the most emotionally arousing pictures. Greater overlap in brain regions sensitive to current emotion and contributing to subsequent memory may be a neural mechanism for emotions to enhance memory more powerfully in women than in men.
Foilb, Allison R.; Bals, Julia; Sarlitto, Mary C.; Christianson, John P.
Distinguishing safety from danger is necessary for survival, but is aberrant in individuals with post-traumatic stress disorder (PTSD). While PTSD is more prevalent in women than men, research on sex differences in safety learning is limited. Here, female rats demonstrated greater fear discrimination than males in a CS+/CS- paradigm. To determine…
Kim, Young Sun; Kim, Nayoung; Kim, Gwang Ha
It is important to understand sex and gender-related differences in gastroesophageal reflux disease (GERD) because gender-related biologic factors might lead to better prevention and therapy. Non-erosive reflux disease (NERD) affects more women than men. GERD symptoms are more frequent in patients with NERD than in those with reflux esophagitis. However, men suffer pathologic diseases such as reflux esophagitis, Barrett’s esophagus (BE), and esophageal adenocarcinoma (EAC) more frequently than women. The prevalence of reflux esophagitis is significantly increased with age in women, especially after their 50s. The mean age of EAC incidence in women is higher than in men, suggesting a role of estrogen in delaying the onset of BE and EAC. In a chronic rat reflux esophagitis model, nitric oxide was found to be an aggravating factor of esophageal injury in a male-predominant way. In addition, the expression of esophageal occludin, a tight junction protein that plays an important role in the esophageal defense mechanism, was up-regulated in women. This explains the male predominance of reflux esophagitis and delayed incidence of BE or EAC in women. Moreover, the symptoms such as heartburn, regurgitation, and extra-esophageal symptoms have been more frequently reported by women than by men, suggesting that sex and gender play a role in symptom perception. Differential sensitivity with augmented symptoms in women might have diagnostic and therapeutic influence. Furthermore, recent studies have suggested that hormone replacement therapy has a protective effect against esophageal cancer. However, an anti-inflammatory role of estrogen remains compelling, which means further study is necessary in this area. PMID:27703114
Etchell, Andrew; Adhikari, Aditi; Weinberg, Lauren S; Choo, Ai Leen; Garnett, Emily O; Chow, Ho Ming; Chang, Soo-Eun
The extent of sex differences in childhood language development is unclear. We conducted a systematic literature review synthesizing results from studies examining sex differences in brain structure and function relevant to language development during childhood. We searched PubMed and Scopus databases, and this returned a total of 46 published studies meeting criteria for inclusion that directly examined sex differences in brain development relevant to language function in children. The results indicate that: (a) sex differences in brain structure or function do not necessarily lead to differences in language task performance; (b) evidence for sex differences in brain and language development are limited; (c) when present, sex differences often interact with a variety of factors such as age and task. Overall, the magnitude of sexual dimorphism of brain developmental trajectories associated with language is not as significant as previously thought. Sex differences were found, however, in studies employing tighter age ranges. This suggests that sex differences may be more prominent during certain developmental stages but are negligible in other stages, likely due to different rates of maturation between the sexes. More research is needed to improve our understanding of how sex differences may arise due to the influence of sex hormones and developmental stages, and how these differences may lead to differences in various language task performance. These studies are expected to provide normative information that may be used in studies examining neurodevelopmental disorders that frequently affect more males than females, and also often affect language development. Copyright © 2018 Elsevier Ltd. All rights reserved.
Fetchenhauer, Detlef; Rohde, Percy A.
Men are more often victims of events like car accidents or (violent) crimes than women with the sole exception of sexual assault. Based on the theory of sexual selection, it has been argued that these sex differences in both perpetration and victimization rates can be attributed to sex differences
Siegfried, William D.; And Others
Both male and female college students rated motivators as important, but females also placed importance on environmental factors. The subject's sex could be predicted by both the importance for self and importance for opposite sex ratings. Females' job preferences were related to their mothers' educational achievement. (Author)
Full Text Available On a sample of 45 children (25 girls and 20 boys age of 9 to 11, who have been training volleyball (one to three years in the club "Sportisimo pajp" in Novi Sad, were applied four motor tests. The aim of this research was to determine differences in the motor status of children of different sex in the school volleyball. Multivariate analysis of variance (MANOVA determined a statistically significant difference in the whole system of analyzed motor variables depending on the sex on studied sample of child¬ren. Univariate analysis of variance (ANOVA showed that girls had better results in va¬riables of flexibility and agility. Boys are better in standing long jump, while sta¬tistically significant differences between means in the speed of alternative movements between girls and boys the not found.
Kanchan, Tanuj; Krishan, Kewal; Aparna, K R; Shyamsundar, S
Analysis of fingerprints and palm prints at the crime scene is vital to identify the suspect and establish a crime. Dermatoglyphics can even be valuable in identification of a dismembered hand during medicolegal investigations to establish the identity of an individual in cases of mass disasters/mass homicides. The present research studies the variation in ridge density in different areas of the palm prints among men and women. The four prominent areas were analysed on the palm prints that included central prominent part of the thenar eminence (P1), hypothenar region; inner to the proximal axial triradius (P2), medial mount; proximal to the triradius of the second digit (P3) and lateral mount; proximal to the triradius of the fifth digit (P4). The mean palm print ridge density was significantly higher among women than men in all the designated areas in both hands except for the P3 area in the right hand. Statistically significant differences were observed in the palm print ridge density between the different palm areas in men and women in right and left hands. No significant right-left differences were observed in the palm print ridge density in any of the four areas of palm prints among men. In women, right-left differences were observed only in the P3 and P4 areas of palm prints. This preliminary study indicates that though the palm print ridge density is a sexually dimorphic variable, its utility for estimation of sex in forensic identification may be limited owing to significant overlapping of values.
Andrew J King
Full Text Available Behavioural traits that co-vary across contexts or situations often reflect fundamental trade-offs which individuals experience in different contexts (e.g. fitness trade-offs between exploration and predation risk. Since males tend to experience greater variance in reproductive success than females, there may be considerable fitness benefits associated with "bolder" behavioural types, but only recently have researchers begun to consider sex-specific and life-history strategies associated with these. Here we test the hypothesis that male three-spined sticklebacks (Gasterosteus aculeatus show high risk but potentially high return behaviours compared to females. According to this hypothesis we predicted that male fish would show greater exploration of their environment in a foraging context, and be caught sooner by an experimenter than females. We found that the time fish spent out of cover exploring their environment was correlated over two days, and males spent significantly more time out of cover than females. Also, the order in which fish were net-caught from their holding aquarium by an experimenter prior to experiments was negatively correlated with the time spent out of cover during tests, and males tended to be caught sooner than females. Moreover, we found a positive correlation between the catch number prior to our experiments and nine months after, pointing towards consistent, long-term individual differences in behaviour.
Harrington, Josephine; Fillmore, Natasha; Gao, Shouguo; Yang, Yanqin; Zhang, Xue; Liu, Poching; Stoehr, Andrea; Chen, Ye; Springer, Danielle; Zhu, Jun; Wang, Xujing; Murphy, Elizabeth
Heart failure preceded by hypertrophy is a leading cause of death, and sex differences in hypertrophy are well known, although the basis for these sex differences is poorly understood. This study used a systems biology approach to investigate mechanisms underlying sex differences in cardiac hypertrophy. Male and female mice were treated for 2 and 3 weeks with angiotensin II to induce hypertrophy. Sex differences in cardiac hypertrophy were apparent after 3 weeks of treatment. RNA sequencing was performed on hearts, and sex differences in mRNA expression at baseline and following hypertrophy were observed, as well as within-sex differences between baseline and hypertrophy. Sex differences in mRNA were substantial at baseline and reduced somewhat with hypertrophy, as the mRNA differences induced by hypertrophy tended to overwhelm the sex differences. We performed an integrative analysis to identify mRNA networks that were differentially regulated in the 2 sexes by hypertrophy and obtained a network centered on PPARα (peroxisome proliferator-activated receptor α). Mouse experiments further showed that acute inhibition of PPARα blocked sex differences in the development of hypertrophy. The data in this study suggest that PPARα is involved in the sex-dimorphic regulation of cardiac hypertrophy. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.
Sagarin, Brad J; Becker, D Vaughn; Guadagno, Rosanna E; Wilkinson, Wayne W; Nicastle, Lionel D
Although heterosexual women and men consistently demonstrate sex differences in jealousy, these differences disappear among lesbians and gay men as well as among heterosexual women and men contemplating same-sex infidelities (infidelities in which the partner and rival are the same sex). Synthesizing these past findings, the present paper offers a reproductive threat-based model of evolved sex differences in jealousy that predicts that the sexes will differ only when the jealous perceivers' reproductive outcomes are differentially at risk. This model is supported by data from a web-based study in which lesbians, gay men, bisexual women and men, and heterosexual women and men responded to a hypothetical infidelity scenario with the sex of the rival randomly determined. After reading the scenario, participants indicated which type of infidelity (sexual versus emotional) would cause greater distress. Consistent with predictions, heterosexual women and men showed a sex difference when contemplating opposite-sex infidelities but not when contemplating same-sex infidelities, whereas lesbians and gay men showed no sex difference regardless of whether the infidelity was opposite-sex or same-sex.
Brad J. Sagarin
Full Text Available Although heterosexual women and men consistently demonstrate sex differences in jealousy, these differences disappear among lesbians and gay men as well as among heterosexual women and men contemplating same-sex infidelities (infidelities in which the partner and rival are the same sex. Synthesizing these past findings, the present paper offers a reproductive threat-based model of evolved sex differences in jealousy that predicts that the sexes will differ only when the jealous perceivers' reproductive outcomes are differentially at risk. This model is supported by data from a web-based study in which lesbians, gay men, bisexual women and men, and heterosexual women and men responded to a hypothetical infidelity scenario with the sex of the rival randomly determined. After reading the scenario, participants indicated which type of infidelity (sexual versus emotional would cause greater distress. Consistent with predictions, heterosexual women and men showed a sex difference when contemplating opposite-sex infidelities but not when contemplating same-sex infidelities, whereas lesbians and gay men showed no sex difference regardless of whether the infidelity was opposite-sex or same-sex.
Full Text Available This paper utilizes five cycles of the General Social Survey in consecutive years from 2006 through 2010 to address the issue of differential wages amongst members of same-sex couples compared to their counterparts in different-sex couples. We find that men in gay couples have wages that are statistically indistinguishable from those of males in heterosexual relationships. By contrast, a sizeable and statistically significant earnings premium exists for lesbians in same-sex couples.
It has long been argued that the legalization of same-sex marriage would have a negative impact on marriage. In this article, I examine how different-sex marriage in the Netherlands was affected by the enactment of two laws: a 1998 law that provided all couples with an institution almost identical to marriage (a “registered partnership”) and a 2001 law that legalized same-sex marriage for the first time in the world. I first construct a synthetic control for the Netherlands using OECD data fo...
It has long been argued that the legalization of same-sex marriage would have a negative impact on marriage. In this article, I examine how different-sex marriage in the Netherlands was affected by the enactment of two laws: a 1998 law that provided all couples with an institution almost identical...... to marriage (a “registered partnership”) and a 2001 law that legalized same-sex marriage for the first time in the world. I first construct a synthetic control for the Netherlands using OECD data for the period 1988–2005 and find that neither law had significant effects on either the overall or different......-sex marriage rate. I next construct a unique individual-level data set covering the period 1995–2005 by combining the Dutch Labor Force Survey and official municipal records. The estimates from a discrete-time hazard model with unobserved heterogeneity for the first-marriage decision confirm the findings...
Pardeller, Silvia; Frajo-Apor, Beatrice; Kemmler, Georg; Hofer, Alex
In order to expand on previous research, this cross-sectional study investigated the relationship between Emotional Intelligence (EI) and cognitive abilities in healthy adults with a special focus on potential sex differences. EI was assessed by means of the Mayer-Salovey-Caruso-Emotional-Intelligence Test (MSCEIT), whereas cognitive abilities were investigated using the Brief Assessment of Cognition in Schizophrenia (BACS), which measures key aspects of cognitive functioning, i.e. verbal memory, working memory, motor speed, verbal fluency, attention and processing speed, and reasoning and problem solving. 137 subjects (65% female) with a mean age of 38.7 ± 11.8 years were included into the study. While males and females were comparable with regard to EI, men achieved significantly higher BACS composite scores and outperformed women in the BACS subscales motor speed, attention and processing speed, and reasoning and problem solving. Verbal fluency significantly predicted EI, whereas the MSCEIT subscale understanding emotions significantly predicted the BACS composite score. Our findings support previous research and emphasize the relevance of considering cognitive abilities when assessing ability EI in healthy individuals.
Full Text Available The identification of biological and ecological factors that contribute to obesity may help in combating the spreading obesity crisis. Sex differences in obesity rates are particularly poorly understood. Here we show that the strong female bias in obesity in many countries is associated with high total fertility rate, which is well known to be correlated with factors such as low average income, infant mortality and female education. We also document effects of reduced access to contraception and increased inequality of income among households on obesity rates. These results are consistent with studies that implicate reproduction as a risk factor for obesity in women and that suggest the effects of reproduction interact with socioeconomic and educational factors. We discuss our results in the light of recent research in dietary ecology and the suggestion that insulin resistance during pregnancy is due to historic adaptation to protect the developing foetus during famine. Increased access to contraception and education in countries with high total fertility rate might have the additional benefit of reducing the rates of obesity in women.
Jankord, Ryan; Turk, James R; Schadt, James C; Casati, Jennifer; Ganjam, Venkataseshu K; Price, Elmer M; Keisler, Duane H; Laughlin, M Harold
Inflammation contributes to disease development, and the neuroimmunoendocrine interface is a potential site of action for inflammatory products like IL-6 to affect health. Although plasma IL-6 can stimulate the activity of the hypothalamo-pituitary-adrenocortical (HPA) axis, the precise role, if any, for IL-6 in the HPA response to nonimmunological stressors is unclear. The purpose of this study was to test the hypothesis that IL-6 in the stalk median eminence (SME) can be directly involved in stimulating ACTH secretion in response to acute stress in female swine. This study was undertaken as a result of finding IL-6 localized to the external zone of the SME next to the hypophyseal portal vessels. Results indicate that content of IL-6 in the SME decreases in response to acute stress along with an increase in nuclear phosphorylated signal transducer and activator of transcription-3 (pSTAT-3) in pituitary corticotrophs and a simultaneous increase in plasma concentrations of IL-6 and ACTH. Furthermore, we show that females concomitantly display greater SME content of IL-6 and greater HPA responsiveness to stress, thereby suggesting that IL-6 release from the SME is an integral factor contributing to enhanced stress responsiveness in females. Our results provide evidence for a direct link between IL-6 and ACTH release and reveal a sex difference in this relationship.
Jankord, Ryan; Turk, James R.; Schadt, James C.; Casati, Jennifer; Ganjam, Venkataseshu K.; Price, Elmer M.; Keisler, Duane H.; Laughlin, M. Harold
Inflammation contributes to disease development, and the neuro-immuno-endocrine interface is a potential site of action for inflammatory products like IL-6 to affect health. Although plasma IL-6 can stimulate the activity of the hypothalamo-pituitary-adrenocortical (HPA) axis, the precise role, if any, for IL-6 in the HPA response to non-immunological stressors is unclear. The purpose of this study was to test the hypothesis that IL-6 in the stalk median eminence (SME) can be directly involved in stimulating ACTH secretion in response to acute stress in female swine. This study was undertaken as a result of finding IL-6 localized to the external zone of the stalk median eminence (SME) next to the hypophyseal portal vessels. Results indicate that content of IL-6 in the SME decreases in response to acute stress along with an increase in phosphorylation of STAT3 in the anterior pituitary and a simultaneous increase in plasma concentrations of IL-6 and ACTH. Furthermore, we show that females concomitantly display greater SME content of IL-6 and greater HPA responsiveness to stress, thereby suggesting that IL-6 release from the SME is an integral factor contributing to enhanced stress responsiveness in females. Our results provide evidence for a direct link between IL-6 and ACTH release and reveal a sex difference in this relationship. PMID:17510233
Jürgen Harreiter; Alexandra Kautzky-Willer
Lifestyle intervention programs are effective in the prevention of type 2 diabetes mellitus (T2DM) in high risk populations. However, most studies only give limited information about the influence of sex and/or gender effectiveness of these interventions. So far, similar outcome was reported for diabetes progression and weight loss. Nevertheless, long-term data on cardiovascular outcome are sparse but favoring women regarding all-cause and cardiovascular mortality. In both men and women, sex ...
Zunzer, Stefan C; von Duvillard, Serge P; Tschakert, Gerhard; Mangus, Brent; Hofmann, Peter
The purpose of the study was to assess the average physical intensity and energy expenditure during a single round of golf on hilly and flat courses in a heterogeneous group of healthy men and women of varying age and golf handicap. Forty-two males and 24 females completed an incremental cycle-ergometer exercise test to determine exercise performance markers. The heart rate (HR), duration, distance, walking speed, ascent and descent were measured via a global positioning system (GPS)/HR monitor during the game and energy expenditure was calculated. Playing 9 or 18-holes of golf, independent of the golf course design, the average HR was not significantly different between sexes or the subgroups. The intensities were light with respect to the percentage of maximal HR and metabolic equivalents of task (METs). Total energy expenditure of all participants was not significantly different for hilly (834 ± 344 kcal) vs. flat courses (833 ± 295 kcal) whereas male players expended significantly greater energy than female players (926 ± 292 vs. 556 ± 180 kcal), but did not have significantly greater relative energy expenditure (2.8 ± 0.8 vs. 2.2 ± 0.7 METs). As a high volume physical activity, playing golf is suggested to yield health benefits. Since the intensity was well below recommended limits, golf may have health related benefits unrelated to the intensity level of the activity.
Townes, Brenda D.; And Others
This study investigates differences in psychological sex, present and past adjustment, and parental influences among homosexual cross-dressers, homosexual non-cross-dressers, applicants for sex change surgery, and heterosexuals. Homosexual non-cross-dressers and heterosexual groups had the most masculine gender role, with the sex change group…
Full Text Available Although profoundly studied, etiology of pancreatic cancer (PC is still rather scant. Exposure to cadmium (Cd, a ubiquitous metal associated with well-established toxic and carcinogenic properties, has been hypothesized to one putative cause of PC. Hence, we analyzed recently published observational studies, meta-analyses, and experimental animal and in vitro studies with the aim of summarizing the evidence of Cd involvement in PC development and describing the possible mechanisms. Consolidation of epidemiological data on PC and exposure to Cd indicated a significant association with an elevated risk of PC among general population exposed to Cd. Cadmium exposure of laboratory animals was showed to cause PC supporting the findings suggested by human studies. The concordance with human and animal studies is buttressed by in vitro studies, although in vitro data interpretation is problematic. In most instances, only significant effects are reported, and the concentrations of Cd are excessive, which would skew interpretation. Previous reports suggest that oxidative stress, apoptotic changes, and DNA cross-linking and hypermethylation are involved in Cd-mediated carcinogenesis. Undoubtedly, a significant amount of work is still needed to achieve a better understanding of the Cd involvement in pancreatic cancer which could facilitate prevention, diagnosis, and therapy of this fatal disease.
Abel, Gillian M
This paper uses Arlie Hochschild's (1983) concept of emotion management and "surface" and "deep acting" to explore how sex workers separate and distance themselves from their public role. Experiences of stigmatisation prevail among sex workers and how stigma is resisted or managed has an impact on their health. In-depth interviews were carried out between August 2006 and April 2007 with 58 sex workers in five cities in New Zealand following decriminalisation of the sex industry. Most participants drew on ideas of professionalism in sustaining a psychological distance between their private and public lives. They utilised "deep acting", transmuting private experiences for use in the work environment, to accredit themselves as professional in their business practices. They also constructed different meanings for sex between public and private relationships with the condom providing an important symbol in separating the two. A few (mostly female street-based) participants were less adept at "deep acting" and relied on drugs to maintain a separation of roles. This paper argues that in an occupation which is highly stigmatised and in which depersonalisation as an aspect of burn-out has been reported as a common occurrence, the ability to draw on strategies which require "deep acting" provides a healthy estrangement between self and role and can be seen as protective. The separation of self from work identity is not damaging as many radical feminists would claim, but an effective strategy to manage emotions. Hochschild, A. (1983). The managed heart: Commercialization of human feeling. Berkeley: University of California Press. Copyright © 2011 Elsevier Ltd. All rights reserved.
Ramikie, Teniel S; Ressler, Kerry J
Trauma-related disorders, such as posttraumatic stress disorder (PTSD) are remarkably common and debilitating, and are often characterized by dysregulated threat responses. Across numerous epidemiological studies, females have been found to have an approximately twofold increased risk for PTSD and other stress-related disorders. Understanding the biological mechanisms of this differential risk is of critical importance. Recent data suggest that the pituitary adenylate cyclase-activating polypeptide (PACAP) pathway is a critical regulator of the stress response across species. Moreover, increasing evidence suggests that this pathway is regulated by both stress and estrogen modulation and may provide an important window into understanding mechanisms of sex differences in the stress response. We have recently shown that PACAP and its receptor (PAC1R) are critical mediators of abnormal processes after psychological trauma. Notably, in heavily traumatized human subjects, there appears to be a robust sex-specific association of PACAP blood levels and PAC1R gene variants with fear physiology, PTSD diagnosis, and symptoms, specifically in females. The sex-specific association occurs within a single-nucleotide polymorphism (rs2267735) that resides in a putative estrogen response element involved in PAC1R gene regulation. Complementing these human data, the PAC1R messenger RNA is induced with fear conditioning or estrogen replacement in rodent models. These data suggest that perturbations in the PACAP-PAC1R pathway are regulated by estrogen and are involved in abnormal fear responses underlying PTSD.
Gupta, Arpana; Mayer, Emeran A; Fling, Connor; Labus, Jennifer S; Naliboff, Bruce D; Hong, Jui-Yang; Kilpatrick, Lisa A
Common brain mechanisms are thought to play a significant role across a multitude of chronic pain syndromes. In addition, there is strong evidence for the existence of sex differences in the prevalence of chronic pain and in the neurobiology of pain. Thus, it is important to consider sex when developing general principals of pain neurobiology. The goal of the current Mini-Review is to evaluate what is known about sex-specific brain alterations across multiple chronic pain populations. A total of 15 sex difference and 143 single-sex articles were identified from among 412 chronic pain neuroimaging articles. Results from sex difference studies indicate more prominent primary sensorimotor structural and functional alterations in female chronic pain patients compared with male chronic pain patients: differences in the nature and degree of insula alterations, with greater insula reactivity in male patients; differences in the degree of anterior cingulate structural alterations; and differences in emotional-arousal reactivity. Qualitative comparisons of male-specific and female-specific studies appear to be consistent with the results from sex difference studies. Given these differences, mixed-sex studies of chronic pain risk creating biased data or missing important information and single-sex studies have limited generalizability. The advent of large-scale neuroimaging databases will likely aid in building a more comprehensive understanding of sex differences and commonalities in brain mechanisms underlying chronic pain. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Heilskov-Hansen, Thomas; Svendsen, Susanne Wulff; Thomsen, Jane Frølund
OBJECTIVES: Sex differences in occupational biomechanical exposures may be part of the explanation why musculoskeletal complaints and disorders tend to be more common among women than among men. We aimed to determine possible sex differences in task distribution and task-specific postures...... correction were used to evaluate sex differences. RESULTS: Statistically significant (psex differences were revealed in task proportions, but the proportions differed by less than 4%. For task exposures, no statistically significant sex differences were found. CONCLUSIONS: Only minor sex differences...... and movements of the upper extremities among Danish house painters, and to establish sex-specific task exposure matrices. METHODS: To obtain task distributions, we sent out a questionnaire to all members of the Painters' Union in Denmark (N = 9364), of whom 53% responded. Respondents reported their task...
Lee, Hyo Jung; Lee, Sang Gyu; Chun, Sung-Youn; Park, Eun-Cheol
Spousal death is a significant event that becomes a turning point in an individual's life. Widowed persons experience new circumstances, which might induce depression. However, the effects of spousal death on depression can differ by sex and culture. Thus, the present study examined the association between depressive levels and experience of spousal death in Korean adults aged older than 45 years. The data were from the Korean Longitudinal Study of Aging from 2010 to 2012. The analysis used frequency analysis to compare the distribution of demographic variables between men and women, and anova to compare 10-item short-form Center for Epidemiological Studies Depression Scale scores as the dependent variable among comparison groups. We also carried out linear mixed model analysis on the association between the 10-item short-form Center for Epidemiological Studies Depression Scale and experience of spousal death. Among 5481 respondents, 2735 were men and 2741 were women. The number of men and women who experienced spousal death were 43 (1.6%) and 181 (6.6%), respectively. Men had lower depressive levels than women when they had been married (men 2.99, women 3.64). Both men and women experiencing spousal death had significantly higher 10-item short-form Center for Epidemiological Studies Depression Scale scores than married men and women (men β = 0.911, P = 0.003; women β = 0.512, P = 0.001; ref: no experience of spousal death). There was a significant association between experience of spousal death and depressive level for both men and women. We suggest that policy practitioners promote community programs that provide bereaved adults with easy access to meaningful social participation and support the minimum cost of living of the widowed. Geriatr Gerontol Int 2017; 17: 322-329. © 2016 Japan Geriatrics Society.
Weinraub, M; Frankel, J
20 18-month-olds were observed with their mothers and 20 with their fathers in laboratory free-play, departure, and separation situations. Parent and infant behaviors were allowed to vary naturally. Although there were no parent sex or infant sex differences in infants' free-play behavior, there were parent sex X infant sex differences in parental free-play behaviors. Parents talked to, sat on the floor more with, and tended to share play more with same-sexed than opposite-sexed infants, and the patterning of free-play behaviors was different for mothers and fathers. During departure, fathers talked to the infants more than mothers. Infants were more distressed in the absence of same-sexed than opposite-sexed parents. There were infant sex X parent sex differences in the relationships between separation distress and parental free-play and departure behaviors. The implications of these findings for understanding differential roles of mothers and fathers, the development of sex differences, and the determinants of separation distress are discussed.
Pollitt, Amanda M; Robinson, Brandon A; Umberson, Debra
Research on gender inequality within different-sex marriages shows that women do more unpaid labor than men, and that the perception of inequality influences perceptions of marital quality. Yet research on same-sex couples suggests the importance of considering how gender is relational. Past studies show that same-sex partners share unpaid labor more equally and perceive greater equity than do different-sex partners, and that lesbian, gay, and bisexual people are less gender conforming than heterosexuals. However, studies have not considered how gender conformity might shape inequalities and marital quality within same- and different-sex unions. In this study, we analyze dyadic data from both spouses in same- and different-sex marriages to explore how sex of spouse and gender conformity influence perceptions of shared power within the relationship, which, in turn, influences marital quality. Results show that greater gender conformity is related to stronger perceptions of shared power in different-sex and male same-sex couples but not in female same-sex couples. Perceptions of shared power are positively associated with marital quality in all union types. Our findings suggest that maintaining hegemonic masculinity and power inequalities may be salient to marriages with men. In female same-sex couples, gender and its relation to power inequalities may carry less meaning.
Llewellyn, Nicole; Rudolph, Karen D.; Roisman, Glenn I.
Research suggests that the pubertal transition, particularly when experienced earlier than age-matched peers, is associated with heightened depression in girls but less depression in boys. This study examined whether stress within other-sex relationships serves as one process through which puberty differentially contributes to depression for girls…
van Straaten, I.; Holland, R.; Finkenauer, C.; Hollenstein, T.; Engels, R.C.M.E.
We investigated to what extent the length of people's gazes during conversations with opposite-sex persons is affected by the physical attractiveness of the partner. Single participants (N = 115) conversed for 5 min with confederates who were rated either as low or high on physical attractiveness.
Brandt, Erin E; Masta, Susan E
Fluorescence is increasingly recognized to be widespread in nature. In particular, some arachnids fluoresce externally, and in spiders the hemolymph fluoresces. In this study, we examined the external fluorescence and the fluorophores of different sexes and life stages of the crab spider Misumena vatia (Clerk 1757), a sit-and-wait predator that feeds on insects as they visit flowers. We designed novel instrumentation to measure external fluorescence in whole specimens. We found that although males and females possess internal fluorophores with similar properties, the external expression of fluorescence varies across sexes and life stages. Spiders fluoresce brightly as immatures. Females maintain their brightness to adulthood, whereas males become increasingly dim as they mature. We suggest that external fluorescence likely contributes to visual signaling in these animals, and that it differs between the sexes as a result of differences in foraging ecology and behavior.
Erin E Brandt
Full Text Available Fluorescence is increasingly recognized to be widespread in nature. In particular, some arachnids fluoresce externally, and in spiders the hemolymph fluoresces. In this study, we examined the external fluorescence and the fluorophores of different sexes and life stages of the crab spider Misumena vatia (Clerk 1757, a sit-and-wait predator that feeds on insects as they visit flowers. We designed novel instrumentation to measure external fluorescence in whole specimens. We found that although males and females possess internal fluorophores with similar properties, the external expression of fluorescence varies across sexes and life stages. Spiders fluoresce brightly as immatures. Females maintain their brightness to adulthood, whereas males become increasingly dim as they mature. We suggest that external fluorescence likely contributes to visual signaling in these animals, and that it differs between the sexes as a result of differences in foraging ecology and behavior.
Mondejar-Jimenez, Jose; Vargas-Vargas, Manuel
Nowadays, almost all curricula in the social sciences contain at least one course in statistics, given the importance of this discipline as an analytical tool. This work identifies the latent factors relating to students' motivation and attitude towards statistics, tests their covariance structure for samples of both sexes, and identifies the…
In current medical practice, research based evidence is an important foundation for clinical decision making. Clinical practice guidelines are a major instrument for keeping physicians up-to-date about this evidence. In order to provide optimal care to both men and women, it is important that sex
Vehof, Jelle; Smitt-Kamminga, Nicole Sillevis; Nibourg, Simone A.; Hammond, Christopher J.
Purpose: To investigate the role of sex on the symptomatology of DED and on the associations between symptoms and signs. Methods: A cross-sectional study was used including 755 dry eye patients from the Groningen Longitudinal Sicca Study (GLOSSY cohort). Patient symptoms were assessed by the Ocular
Lam, Carolyn S P; McEntegart, Margaret; Claggett, Brian
BACKGROUND: We examined the association of sex with clinical characteristics and outcomes in patients following myocardial infarction (MI) in the Valsartan in Acute Myocardial Infarction Trial (VALIANT). METHODS AND RESULTS: A total of 4570 women and 10 133 men with heart failure (HF), left...
Karbon, Mariss; And Others
Assesses beliefs of 32 male and 35 female middle-class preschool children about the frequency and intensity with which girls, boys, women, and men experience anger, sadness, and happiness. Children's beliefs are complex; they vary as a function of the target person's age and sex and of the specific emotion. (SLD)
Maschietto, Mariana; Bastos, Laura Caroline; Tahira, Ana Carolina; Bastos, Elen Pereira; Euclydes, Veronica Luiza Vale; Brentani, Alexandra; Fink, Günther; de Baumont, Angelica; Felipe-Silva, Aloísio; Francisco, Rossana Pulcineli Vieira; Gouveia, Gisele; Grisi, Sandra Josefina Ferraz Ellero; Escobar, Ana Maria Ulhoa; Moreira-Filho, Carlos Alberto; Polanczyk, Guilherme Vanoni; Miguel, Euripedes Constantino; Brentani, Helena
Sex differences in the prevalence of psychiatric disorders are well documented, with exposure to stress during gestation differentially impacting females and males. We explored sex-specific DNA methylation in the cord blood of 39 females and 32 males born at term and with appropriate weight at birth regarding their potential connection to psychiatric outcomes. Mothers were interviewed to gather information about environmental factors (gestational exposure) that could interfere with the methylation profiles in the newborns. Bisulphite converted DNA was hybridized to Illumina HumanMethylation450 BeadChips. Excluding XYS probes, there were 2,332 differentially methylated CpG sites (DMSs) between sexes, which were enriched within brain modules of co-methylated CpGs during brain development and also differentially methylated in the brains of boys and girls. Genes associated with the DMSs were enriched for neurodevelopmental disorders, particularly for CpG sites found differentially methylated in brain tissue between patients with schizophrenia and controls. Moreover, the DMS had an overlap of 890 (38%) CpG sites with a cohort submitted to toxic exposition during gestation. This study supports the evidences that sex differences in DNA methylation of autosomes act as a primary driver of sex differences that are found in psychiatric outcomes.
The differences of learning and memory between males and females have been well documented and confirmed by both human and animal studies. The sex differences in cognition started from early stage of neuronal development and last through entire life span. The major biological basis of the gender-dependent cognitive activity includes two major components: sex hormone and sex-related characteristics, such as sex-determining region of the Y chromosome (SRY) protein. However, the knowledge of how much biology of sex contributes to normal cognitive function and elite athletes in various sports are still pretty limited. In this review, we will be focusing on sex differences in spatial learning and memory - especially the role of male- and female-type cognitive behaviors in sports.
Full Text Available The differences of learning and memory between males and females have been well documented and confirmed by both human and animal studies. The sex differences in cognition started from early stage of neuronal development and last through entire lifespan. The major biological basis of the gender-dependent cognitive activity includes two major components: sex hormone and sex-related characteristics, such as sex-determining region of the Y chromosome (SRY protein. However, the knowledge of how much biology of sex contributes to normal cognitive function and elite athletes in various sports are still pretty limited. In this review, we will be focusing on sex differences in spatial learning and memory – especially the role of male- and female-type cognitive behaviors in sports.
van Loo, Hanna M; Aggen, Steven H; Gardner, Charles O; Kendler, Kenneth S
Major depression (MD) occurs about twice as often in women as in men, but it is unclear whether sex differences subsist after disease onset. This study aims to elucidate potential sex differences in rates and risk factors for MD recurrence, in order to improve prediction of course of illness and understanding of its underlying mechanisms. We used prospective data from a general population sample (n = 653) that experienced a recent episode of MD. A diverse set of potential risk factors for recurrence of MD was analyzed using Cox models subject to elastic net regularization for males and females separately. Accuracy of the prediction models was tested in same-sex and opposite-sex test data. Additionally, interactions between sex and each of the risk factors were investigated to identify potential sex differences. Recurrence rates and the impact of most risk factors were similar for men and women. For both sexes, prediction models were highly multifactorial including risk factors such as comorbid anxiety, early traumas, and family history. Some subtle sex differences were detected: for men, prediction models included more risk factors concerning characteristics of the depressive episode and family history of MD and generalized anxiety, whereas for women, models included more risk factors concerning early and recent adverse life events and socioeconomic problems. No prominent sex differences in risk factors for recurrence of MD were found, potentially indicating similar disease maintaining mechanisms for both sexes. Course of MD is a multifactorial phenomenon for both males and females.
Mutagoma, Mwumvaneza; Kayitesi, Catherine; Gwiza, Aimé; Ruton, Hinda; Koleros, Andrew; Gupta, Neil; Balisanga, Helene; Riedel, David J; Nsanzimana, Sabin
HIV prevalence is disproportionately high among female sex workers compared to the general population. Many African countries lack useful data on the size of female sex worker populations to inform national HIV programmes. A female sex worker size estimation exercise using three different venue-based methodologies was conducted among female sex workers in all provinces of Rwanda in August 2010. The female sex worker national population size was estimated using capture-recapture and enumeration methods, and the multiplier method was used to estimate the size of the female sex worker population in Kigali. A structured questionnaire was also used to supplement the data. The estimated number of female sex workers by the capture-recapture method was 3205 (95% confidence interval: 2998-3412). The female sex worker size was estimated at 3348 using the enumeration method. In Kigali, the female sex worker size was estimated at 2253 (95% confidence interval: 1916-2524) using the multiplier method. Nearly 80% of all female sex workers in Rwanda were found to be based in the capital, Kigali. This study provided a first-time estimate of the female sex worker population size in Rwanda using capture-recapture, enumeration, and multiplier methods. The capture-recapture and enumeration methods provided similar estimates of female sex worker in Rwanda. Combination of such size estimation methods is feasible and productive in low-resource settings and should be considered vital to inform national HIV programmes. © The Author(s) 2015.
Stuijfzand, Suzannah; De Wied, Minet; Kempes, Maaike; van der Graaff, Jolien; Branje, Susan; Meeus, Wim
Although gender differences in affective empathy are well established, evidence of gender differences in the development of affective empathy is inconsistent. Consideration of same-sex versus other-sex affective empathy may assist in elucidating these inconsistencies. Gender differences were
Luxen, Marc F.
Biosocial theory claims that evolution did not design human psychological sex differences. It argues that these are the result of the allocation of men and women into different sex roles, based on physical differences. This article argues, however, that biosocial theory is not an alternative to
Hammen, Constance L.; Padesky, Christine A.
Although epidemiological data have documented sex differences in depression, the nature and origins of the differences are unclear. Depression in a large sample of young, unmarried college students was measured and described by the Beck Depression Inventory. Considers the consequences of sex differences in depressive responses, including…
Dufur, Mikaela J.; Howell, Nyssa C.; Downey, Douglas B.; Ainsworth, James W.; Lapray, Alice J.
Research on family structure has led some to claim that sex-based parenting differences exist. But if such differences exist in single-parent families, the absence of a second parent rather than specific sex-typed parenting might explain them. We examine differences in mothering and fathering behavior in single-parent households, where number of…
Haggis, Jane; Mulholland, Monique
This paper aimed to problematise what is meant by 'difference' and consider what such a reinterpretation might mean for methodological interventions in sex education research. Our concern is the tendency for sex education research to treat difference as a set of categories to be "added-on", such as religious difference, cultural…
F. Javier Ayesta
The absence of difference between sexes persist when data are adjusted either by age, psychiatric diagnosis, dependence, depression symptoms, perception of support, number of previous attempts, and drugs used during the treatment. The differences between sexes found in other studies might be due to the fact that in some other countries things are different, or that some confounding factors have not been ruled out.
Cornez, Gilles; ter Haar, Sita M; Cornil, Charlotte A; Balthazart, Jacques
Large morphological sex differences in the vertebrate brain were initially identified in song control nuclei of oscines. Besides gross differences between volumes of nuclei in males and females, sex differences also concern the size and dendritic arborization of neurons and various neurochemical
Weerman, F.M.; Hoeve, M.
In this article, we investigate sex differences in the relationship between peers and delinquency. We analyse to what extent peers have different effects on delinquency among girls and boys, and to what extent sex differences in the level of delinquency can be explained by differential exposure or
Stuijfzand, S; De Wied, M; Kempes, M; Van der Graaff, J; Branje, S; Meeus, W.H.J.
Although gender differences in affective empathy are well established, evidence of gender differences in the development of affective empathy is inconsistent. Consideration of same-sex versus other-sex affective empathy may assist in elucidating these inconsistencies. Gender differences were
Tschernegg, Melanie; Neuper, Christa; Schmidt, Reinhold; Wood, Guilherme; Kronbichler, Martin; Fazekas, Franz; Enzinger, Christian; Koini, Marisa
Background Although established as a general notion in society, there is no solid scientific foundation for the existence of sex-differences in multitasking. Reaction time and accuracy in dual task conditions have an inverse relationship relative to single task, independently from sex. While a more disseminated network, parallel to decreasing accuracy and reaction time has been demonstrated in dual task fMRI studies, little is known so far whether there exist respective sex-related difference...
Sorokowski, Piotr; Sorokowska, Agnieszka; Witzel, Christoph
At first glance, color preferences might seem to be the most subjective and context-dependent aspects of color cognition. Yet they are not. The present study compares color preferences of women and men from an industrialized and a remote, nonindustrialized culture. In particular, we investigated preferences in observers from Poland and from the Yali in Papua, respectively. Not surprisingly, we found that color preferences clearly differed between the two communities and also between sexes. However, despite the pronounced cultural differences, the way in which men and women differed from each other was almost the same in both cultures. At the same time, this sexual contrast was not specific to biological components of color vision. Our results reveal a pattern of sexual dimorphism that transcends extreme differences in culture and ecology. They point toward strong cross-cultural constraints beyond the biological predispositions of nature and the cultural particularities of nurture.
Full Text Available Fungal diversity within plant roots is affected by several factors such as dispersal limitation, habitat filtering, and plant host preference. Given the differences in life style between symbiotic and non-symbiotic fungi, the main factors affecting these two groups of fungi may be different. We assessed the diversity of root associated fungi of Rhododendron decorum using internal transcribed spacer (ITS sequencing and terminal restriction fragment length polymorphism (T-RFLP analysis, and our aim was to evaluate the role of different factors in structuring ericoid mycorrhizal (ERM and non-ericoid mycorrhizal (NEM fungal communities. Thirty-five fungal operational taxonomic units (OTUs were found in roots of R. decorum, of which 25 were putative ERM fungal species. Of the two main groups of known ERM, helotialean fungi were more abundant and common than sebacinalean species. Geographic and host patterning of the fungal assemblages were different for ERM and NEM. The distribution of putative ERM fungal terminal restriction fragments (TRFs showed that there were more common species within ERM than in the NEM fungal assemblages. Results of Mantel tests indicated that the composition of NEM fungal assemblages correlated with geographic parameters while ERM fungal assemblages lacked a significant geographic pattern and instead were correlated with host genotype. Redundancy analysis (RDA showed that the NEM fungal assemblages were significantly correlated with latitude, longitude, elevation, mean annual precipitation (MAP, and axis 2 of a host-genetic principle component analysis (PCA, while ERM fungal assemblages correlated only with latitude and axis 1 of the host-genetic PCA. We conclude that ERM and NEM assemblages are affected by different factors, with the host genetic composition more important for ERM and geographic factors more important for NEM assemblages. Our results contribute to understanding the roles of dispersal limitation, abiotic
Full Text Available BACKGROUND: Tinnitus refers to auditory phantom sensation. It is estimated that for 2% of the population this auditory phantom percept severely affects the quality of life, due to tinnitus related distress. Although the overall distress levels do not differ between sexes in tinnitus, females are more influenced by distress than males. Typically, pain, sleep, and depression are perceived as significantly more severe by female tinnitus patients. Studies on gender differences in emotional regulation indicate that females with high depressive symptoms show greater attention to emotion, and use less anti-rumination emotional repair strategies than males. METHODOLOGY: The objective of this study was to verify whether the activity and connectivity of the resting brain is different for male and female tinnitus patients using resting-state EEG. CONCLUSIONS: Females had a higher mean score than male tinnitus patients on the BDI-II. Female tinnitus patients differ from male tinnitus patients in the orbitofrontal cortex (OFC extending to the frontopolar cortex in beta1 and beta2. The OFC is important for emotional processing of sounds. Increased functional alpha connectivity is found between the OFC, insula, subgenual anterior cingulate (sgACC, parahippocampal (PHC areas and the auditory cortex in females. Our data suggest increased functional connectivity that binds tinnitus-related auditory cortex activity to auditory emotion-related areas via the PHC-sgACC connections resulting in a more depressive state even though the tinnitus intensity and tinnitus-related distress are not different from men. Comparing male tinnitus patients to a control group of males significant differences could be found for beta3 in the posterior cingulate cortex (PCC. The PCC might be related to cognitive and memory-related aspects of the tinnitus percept. Our results propose that sex influences in tinnitus research cannot be ignored and should be taken into account in functional
In this article, the author discusses several research reports demonstrating the existence of sex differences in cognitive function and language skills. Although dozens of studies published in the past five years have demonstrated dramatic sex differences in autonomic function, the educational literature has not emphasized those studies and their…
Examines competing claims of two explanations of sex differences in social behavior, social role theory, and evolutionary psychology. Findings associated with social role theory are weighed against evolutionary explanations. It is suggested that evolutionary theory better accounts for the overall pattern of sex differences and for their origins.…
Lee, S.H.; Noort, M.W.M.L. van den; Bosch, M.P.C.; Lim, S.
Background: Many animal experimental studies have been performed to investigate the efficacy of acupuncture in Parkinson's disease (PD). Sex differences are a major issue in all diseases including PD. However, to our knowledge, there have been no reviews investigating sex differences on the
Eberhart, Nicole K.; Shih, Josephine H.; Hammen, Constance L.; Brennan, Patricia A.
This study examined sex differences in risk factors associated with adolescent depression in a large sample of boys and girls. Moderation and mediation explanatory models of the sex difference in likelihood of depression were examined. Findings indicate that the factors associated with depression in adolescent boys and girls are quite similar. All…
Koehl, Muriel; Battle, Sally; Meerlo, Peter
Study Objectives: Numerous clinical studies and sleep surveys have shown pronounced sex differences in the occurrence of insomnia and other sleep pathologies. It has been suggested that sex differences in sleep, while subtle under baseline conditions, may increase in magnitude under biological or
Shields, Stephanie A.
Describes the origin and development of the variability hypothesis as applied to the study of social and psychological sex differences. Explores changes in the hypothesis over time, social and scientific factors that fostered its acceptance, and possible parallels between the variability hypothesis and contemporary theories of sex differences.…
Wijnhoven, Hanneke A H; Vet, Henrica C W de; Picavet, H Susan J
Many studies report a female predominance in the prevalence of chronic musculoskeletal pain (CMP) but the mechanisms explaining these sex differences are poorly understood. Data from a random postal questionnaire survey in the Dutch general population were used to examine whether sex differences in
Ocklenburg, Sebastian; Hirnstein, Marco; Ohmann, Hanno Andreas; Hausmann, Markus
Several studies have demonstrated that women believe they are more prone to left-right confusion (LRC) than men. However, while some studies report that there is also a sex difference in LRC tasks favouring men, others report that men and women perform equally well. Recently, it was suggested that sex differences only emerge in LRC tasks when they…
McIntosh, John L.; Santos, John F.
Annual official statistics for specific methods of suicide (firearms, hanging, poisons) by age for different sex and racial groups (Whites, Blacks, non-Whites excluding Black) were examined from 1960 to 1978. Comparisons among the age-sex-race groups, along with trends over time and differences in the methods employed, were noted. (Author/ABL)
Leon-Garcia, Sandra M; Roeder, Hilary A; Nelson, Katharine K; Liao, Xiaoyan; Pizzo, Donald P; Laurent, Louise C; Parast, Mana M; LaCoursiere, D Yvette
Adverse effects of obesity have been linked to inflammation in various tissues, but studies on placental inflammation and obesity have demonstrated conflicting findings. We sought to investigate the influence of pregravid obesity and fetal sex on placental histopathology while controlling for diabetes and hypertension. Placental histopathology focusing on inflammatory markers of a cohort of normal weight (BMI = 20-24.9) and obese (BMI ≥ 30) patients was characterized. Demographic, obstetric and neonatal variables were assessed. 192 normal and 231 obese women were included. Placental characteristics associated with obesity and fetal sex independent of diabetes and hypertension were placental disc weight >90(th) percentile, decreased placental efficiency, chronic villitis (CV), fetal thrombosis, and normoblastemia. Additionally, female fetuses of obese mothers had higher rates of CV and fetal thrombosis. Increasing BMI increased the risk of normoblastemia and CV. The final grade and extent of CV was significantly associated with obesity and BMI, but not fetal gender. Finally, CV was less common in large-for-gestation placentas. Maternal obesity results in placental overgrowth and fetal hypoxia as manifested by normoblastemia; it is also associated with an increased incidence of CV and fetal thrombosis, both more prevalent in female placentas. We have shown for the first time that the effect of maternal obesity on placental inflammation is independent of diabetes and hypertension, but significantly affected by fetal sex. Our data also point to the intriguing possibility that CV serves to normalize placental size, and potentially fetal growth, in the setting of maternal obesity. Copyright © 2015. Published by Elsevier Ltd.
Kunio, Mie; Wong, Gee; Markham, Peter M; Edelman, Elazer R
Sex-related differences have been noted in cardiovascular anatomy, pathophysiology, and treatment responses, yet we continued to drive evaluation of vascular device development in animal models without consideration of animal sex. We aimed to understand sex-related differences in the vascular responses to stent implantation by analyzing the pooled data of endovascular interventions in 164 Yucatan mini-swine (87 female, 77 male). Bare metal stents (BMS) or drug-eluting stents (DES) were implanted in 212 coronary arteries (63 single BMS implantation, 68 single DES implantation, 33 overlapped BMS implantation, and 48 overlapped DES implantation). Histomorphological parameters were evaluated from vascular specimens at 3-365 days after stent implantation and evaluated values were compared between female and male groups. While neointima formation at all times after implantation was invariant to sex, statistically significant differences between female and male groups were observed in injury, inflammation, adventitial fibrosis, and neointimal fibrin deposition. These differences were observed independently, i.e., for different procedure types and at different follow-up timings. Only subtle temporal sex-related differences were observed in extent and timing of resolution of inflammation and fibrin clearance. These subtle sex-related differences may be increasingly important as interventional devices meld novel materials that erode and innovations in drug delivery. Erodible materials may act differently if inflammation has a different temporal sequence with sex, and drug distribution after balloon or stent delivery might be different if the fibrin clearance speaks to different modes of pharmacokinetics in male and female swine.
Lykins, Amy D; Meana, Marta; Strauss, Gregory P
It has been suggested that sex differences in the processing of erotic material (e.g., memory, genital arousal, brain activation patterns) may also be reflected by differential attention to visual cues in erotic material. To test this hypothesis, we presented 20 heterosexual men and 20 heterosexual women with erotic and non-erotic images of heterosexual couples and tracked their eye movements during scene presentation. Results supported previous findings that erotic and non-erotic information was visually processed in a different manner by both men and women. Men looked at opposite sex figures significantly longer than did women, and women looked at same sex figures significantly longer than did men. Within-sex analyses suggested that men had a strong visual attention preference for opposite sex figures as compared to same sex figures, whereas women appeared to disperse their attention evenly between opposite and same sex figures. These differences, however, were not limited to erotic images but evidenced in non-erotic images as well. No significant sex differences were found for attention to the contextual region of the scenes. Results were interpreted as potentially supportive of recent studies showing a greater non-specificity of sexual arousal in women. This interpretation assumes there is an erotic valence to images of the sex to which one orients, even when the image is not explicitly erotic. It also assumes a relationship between visual attention and erotic valence.
Liker, András; Freckleton, Robert P; Remeš, Vladimir; Székely, Tamás
Male and female parents often provide different type and amount of care to their offspring. Three major drivers have been proposed to explain parental sex roles: (1) differential gametic investment by males and females that precipitates into sex difference in care, (2) different intensity of sexual selection acting on males and females, and (3) biased social environment that facilitates the more common sex to provide more care. Here, we provide the most comprehensive assessment of these hypotheses using detailed parental care data from 792 bird species covering 126 families. We found no evidence for the gametic investment hypothesis: neither gamete sizes nor gamete production by males relative to females was related to sex difference in parental care. However, sexual selection correlated with parental sex roles, because the male share in care relative to female decreased with both extra-pair paternity and frequency of male polygamy. Parental sex roles were also related to social environment, because male parental care increased with male-biased adult sex ratios (ASRs). Taken together, our results are consistent with recent theories suggesting that gametic investment is not tied to parental sex roles, and highlight the importance of both sexual selection and ASR in influencing parental sex roles. © 2015 The Author(s). Evolution © 2015 The Society for the Study of Evolution.
Kanazawa, Satoshi; Reyniers, Diane J
Recent studies conclude that men on average have higher intelligence than women by 3-5 IQ points. However, the ultimate evolutionary question of why men should have evolved to have higher intelligence than women remains. We suggest that men may have slightly higher intelligence than women through 4 mechanisms: (1) assortative mating of intelligent men and beautiful women, (2) assortative mating of tall men and beautiful women, (3) an extrinsic correlation between height and intelligence produced by Mechanisms 1 and 2, and (4) a higher-than-expected offspring sex ratio (more sons) among tall (and hence intelligent) parents. Consistent with our suggestion, we show that men may have higher IQs than women because they are taller, and once we control for height women have slightly higher IQs than men.The correlation between height and IQ and the female advantage in intelligence persist even after we control for health as a measure of genetic quality, as well as physical attractiveness, age, race, education, and earnings. Height is also strongly associated with intelligence within each sex.
It has long been argued that the legalization of same-sex marriage would have a negative impact on marriage. In this article, I examine how different-sex marriage in the Netherlands was affected by the enactment of two laws: a 1998 law that provided all couples with an institution almost identical to marriage (a "registered partnership") and a 2001 law that legalized same-sex marriage for the first time in the world. I first construct a synthetic control for the Netherlands using OECD data for the period 1988-2005 and find that neither law had significant effects on either the overall or different-sex marriage rate. I next construct a unique individual-level data set covering the period 1995-2005 by combining the Dutch Labor Force Survey and official municipal records. The estimates from a discrete-time hazard model with unobserved heterogeneity for the first-marriage decision confirm the findings in the aggregate analysis. The effects of the two laws are heterogeneous, with presumably more-liberal individuals (as defined by their residence or ethnicity) marrying less after passage of both laws and potentially more-conservative individuals marrying more after passage of each law.
Males are born in excess of females and the ratio is expressed as M/F (male/female births=secondary sex ratio, also known as secondary sex ratio). This is expected to approximate 1.048. Racial M/F disparities are known. A recent study in China showed that pregravid systolic hypertension is higher in women who delivered a boy than in those who had a girl. This study was carried out in order to identify the effect of pregravid hypertension in the United States on M/F by race. Monthly male and female live births by race for the entire US along with the presence/absence of hypertension were obtained from the website of the Centers for Disease Control and Prevention for 2007-2015 for the four racial groups: American Indian or Alaska Native, Asian or Pacific Islander, Black or African American and White. This study analysed 36,364,253 live births. For White births, mothers who had chronic hypertension were likelier to have male than female offspring when compared to non-hypertensives (p=0.003). Conversely, Black or African American mothers who had hypertension were less likely to have male than female offspring when compared to non-hypertensives (p=0.022). There were F differences for/F differences for the presence or absence of hypertension for the other two races or for the total. It is possible that hypothesised innate interracial periconceptual hormonal differences may modulate M/F responses to hypertension in different races. Copyright © 2017 Elsevier B.V. All rights reserved.
Walum, Hasse; Larsson, Henrik; Westberg, Lars; Lichtenstein, Paul; Magnusson, Patrik K E
According to the theory of evolved sex differences in jealousy, the challenge for women to ensure paternal investment increased their jealousy response to emotional infidelity, whereas paternal uncertainty exerted selective pressures that shaped men to become more distressed by sexual infidelity. Several studies have investigated whether the effect of these sexually dimorphic selection pressures can be detected in contemporary human populations, with conflicting results. To date, no genetically informed studies of sex differences in jealousy have been conducted. We used data from the Screening Across the Lifespan of Twins Younger (SALTY) sample, containing information concerning self-rated jealousy from 3,197 complete twin pairs collected by the Swedish Twin Registry. Intra-class correlations and structural equation models were used to assess the genetic influence on jealousy and to investigate sex differences at genetic level. We saw a highly significant sex effect on the relationship between infidelity types, indicating that men, relative to women, reported greater jealousy in response to sexual infidelity than in response to emotional infidelity. The twin models revealed significant heritabilities for both sexual (32%) and emotional (26%) jealousy. The heritabilities were of a similar magnitude in both sexes, and no qualitative sex differences could be detected. We show for the first time that variance in jealousy is to some extent explained by genetic factors. Even though our results from the mean value analyses are in line with the theory of evolved sex differences in jealousy, we could not identify any sex differences on a genetic level.
Vaskinn, Anja; Sundet, Kjetil; Simonsen, Carmen; Hellvin, Tone; Melle, Ingrid; Andreassen, Ole A
To investigate sex differences in neurocognition and social functioning in schizophrenia and bipolar disorder and the possible role of sex as a moderator of this relationship. Participants with schizophrenia (60 women/94 men), bipolar I disorder (55 women/51 men), and healthy controls (158 women/182 men) were assessed with an extensive neuropsychological test battery and a social functioning questionnaire. We found significant main effects of sex for neuropsychological tests (p neuropsychological tests (except attention and working memory). Both clinical groups performed below healthy controls for all neuropsychological tests (except attention). Post hoc comparisons of persons with schizophrenia and healthy controls yielded significant interaction effects (p neuropsychological tests (California Verbal Learning Test II [CVLT-II], Color-Word Interference, and Interference/Switching), with men with schizophrenia being disproportionally disadvantaged compared with their female counterparts. Regression analyses investigating sex as a moderator between neurocognition and social functioning showed that neurocognition predicted social functioning in schizophrenia, whereas sex predicted social functioning in healthy controls. Sex was not a moderator in any of the three groups. This study is the first to find neurocognitive sex differences for bipolar disorder and replicated previous findings for schizophrenia. The data did not support the hypothesis that sex is a moderator between neurocognition and social functioning. Clinical implications include the use of different cognitive remediation strategies based on sex. PsycINFO Database Record (c) 2011 APA, all rights reserved.
Pedersen, J M; Glickman, S E; Frank, L G; Beach, F A
Social, locomotor, and object play were studied in a colony of five male and five female peer-reared spotted hyenas during 12 1-hr tests while the animals were 13-19 months of age. Animals were tested in both same-sex and mixed-sex groups and were stimulated to play by the introduction of fresh straw and sawdust bedding. Each test was videotaped and the frequency of each type of play was determined by a time sampling procedure. Females played more frequently than males, however, the category of play which was elevated depended upon the social context during testing. In same-sex tests the frequency of vigorous social play displayed by females markedly exceeded that by males, but no comparable sex difference appeared in mixed-sex tests. Females engaged in locomotor play more frequently than males in mixed-sex tests, but no comparable sex difference appeared in same-sex tests. No sex difference in object play was observed. Two male and two female hyenas were gonadectomized prior to the initiation of the present sequence of tests. The results suggest that gonadectomy during the prepubertal period does not affect the frequency of play behavior. However, the small sample sizes preclude any conclusive determination of the effects of these gonadectomies on play.
Poeppl, Timm B.; Langguth, Berthold; Rupprecht, Rainer; Safron, Adam; Bzdok, Danilo; Laird, Angela R.; Eickhoff, Simon B.
Sexuality as to its etymology presupposes the duality of sexes. Using quantitative neuroimaging meta-analyses, we demonstrate robust sex differences in the neural processing of sexual stimuli in thalamus, hypothalamus, and basal ganglia. In a narrative review, we show how these relate to the well-established sex differences on the behavioral level. More specifically, we describe the neural bases of known poor agreement between self-reported and genital measures of female sexual arousal, of previously proposed male proneness to affective sexual conditioning, as well as hints of unconscious activation of bonding mechanisms during sexual stimulation in women. In summary, our meta-analytic review demonstrates that neurofunctional sex differences during sexual stimulation can account for well-established sex differences in sexual behavior. PMID:27742561
This commentary provides a brief overview of theory and research that supports the idea that sexism may be related to the disproportionate negative cardiovascular health outcomes in women. It describes sexism as a stressor and outlines its association with a variety of health outcomes as evidence for why sex disparities should be examined within the context of pervasive inequities. To date, population-based studies have not explicitly examined the relationship between sexism and cardiovascular disease, but smaller studies have yielded fairly consistent results. It is suggested that future research should aim to examine the influence of 2 types of sexism (ie, hostile and benevolent) and that daily or within-day designs be used to assess cognitive, behavioral and physiological responses to everyday sexist experiences.
Heil, Martin; Jansen-Osmann, Petra
Sex differences in mental rotation were investigated as a function of stimulus complexity with a sample size of N = 72. Replicating earlier findings with polygons, mental rotation was faster for males than for females, and reaction time increased with more complex polygons. Additionally, sex differences increased for complex polygons. Most importantly, however, mental rotation speed decreased with increasing complexity for women but did not change for men. Thus, the sex effects reflect a difference in strategy, with women mentally rotating the polygons in an analytic, piecemeal fashion and men using a holistic mode of mental rotation.
Full Text Available Objective: To investigate the prevalence of subclinical hypothyroidism (SCH in Korean adults and identify the risk factors for the occurrence of SCH by sex. Design and methods: This study used data from the Sixth Korea National Health and Nutrition Examination Survey (KNHANES VI, a cross-sectional, nationally representative survey, which comprises a health interview survey, a health examination survey and a nutrition survey. To examine SCH, the reference range of thyroid-stimulating hormone (TSH was defined using both the range provided by the test kit manufacturer (SCH-M and a population-based range (SCH-P. We investigated the prevalence of SCH and its risk factors by sex using both reference ranges. Results: The prevalence of SCH in Koreans according to SCH-M (0.35–5.5 μIU/mL was 5.6%, and 3.3% with SCH-P (0.62–6.68 μIU/mL. For men, smoking significantly reduced the incidence of SCH, positive anti-thyroid peroxidase antibody (TPOAb significantly increased the risk of SCH, and in an adjusted model, the risk of SCH in all quartiles increased as the urine iodine creatinine ratio (UICR quartile increased. For women, positive TPOAb was confirmed as a risk factor for SCH, as was the highest UICR quartile. Furthermore, the odds ratio for SCH in urban vs rural residence was 1.78. Conclusions: The prevalence rates of SCH were similar to those reported in the literature and previously known risk factors were confirmed using both TSH reference ranges. The notable findings from this study are that the increased risk of SCH with increased iodine intake was more marked in men than in women and that residential area may be a risk factor for SCH in women.
Makris, Nikos; Swaab, Dick F.; van der Kouwe, Andre; Abbs, Brandon; Boriel, Denise; Handa, Robert J.; Tobet, Stuart; Goldstein, Jill M.
There is increasing evidence regarding the importance of the hypothalamus for understanding sex differences in relation to neurological, psychiatric, endocrine and sleep disorders. Although different in histology, physiology, connections and function, multiple hypothalamic nuclei subserve
Bartley, E J; Fillingim, R B
Recent years have witnessed substantially increased research regarding sex differences in pain. The expansive body of literature in this area clearly suggests that men and women differ in their responses to pain, with increased pain sensitivity and risk for clinical pain commonly being observed among women. Also, differences in responsivity to pharmacological and non-pharmacological pain interventions have been observed; however, these effects are not always consistent and appear dependent on treatment type and characteristics of both the pain and the provider. Although the specific aetiological basis underlying these sex differences is unknown, it seems inevitable that multiple biological and psychosocial processes are contributing factors. For instance, emerging evidence suggests that genotype and endogenous opioid functioning play a causal role in these disparities, and considerable literature implicates sex hormones as factors influencing pain sensitivity. However, the specific modulatory effect of sex hormones on pain among men and women requires further exploration. Psychosocial processes such as pain coping and early-life exposure to stress may also explain sex differences in pain, in addition to stereotypical gender roles that may contribute to differences in pain expression. Therefore, this review will provide a brief overview of the extant literature examining sex-related differences in clinical and experimental pain, and highlights several biopsychosocial mechanisms implicated in these male-female differences. The future directions of this field of research are discussed with an emphasis aimed towards further elucidation of mechanisms which may inform future efforts to develop sex-specific treatments.
Lurye, Leah E.; Zosuls, Kristina M.; Ruble, Diane N.
The relationship among gender identity, sex typing, and adjustment has attracted the attention of social and developmental psychologists for many years. However, they have explored this issue with different assumptions and different approaches. Generally the approaches differ regarding whether sex typing is considered adaptive versus maladaptive, measured as an individual or normative difference, and whether gender identity is regarded as a unidimensional or multidimensional construct. In this chapter, we consider both perspectives and suggest that the developmental timing and degree of sex typing, as well as the multidimensionality of gender identity, be considered when examining their relationship to adjustment. PMID:18521861
Chatterjee, Aniruddha; Lagisz, Malgorzata; Rodger, Euan J; Zhen, Li; Stockwell, Peter A; Duncan, Elizabeth J; Horsfield, Julia A; Jeyakani, Justin; Mathavan, Sinnakaruppan; Ozaki, Yuichi; Nakagawa, Shinichi
The sex drive hypothesis predicts that stronger selection on male traits has resulted in masculinization of the genome. Here we test whether such masculinizing effects can be detected at the level of the transcriptome and methylome in the adult zebrafish brain. Although methylation is globally similar, we identified 914 specific differentially methylated CpGs (DMCs) between males and females (435 were hypermethylated and 479 were hypomethylated in males compared to females). These DMCs were prevalent in gene body, intergenic regions and CpG island shores. We also discovered 15 distinct CpG clusters with striking sex-specific DNA methylation differences. In contrast, at transcriptome level, more female-biased genes than male-biased genes were expressed, giving little support for the male sex drive hypothesis. Our study provides genome-wide methylome and transcriptome assessment and sheds light on sex-specific epigenetic patterns and in zebrafish for the first time. Copyright © 2016 Elsevier B.V. All rights reserved.
Bramble, Matthew S; Lipson, Allen; Vashist, Neerja; Vilain, Eric
Sex differences in brain development and postnatal behavior are determined largely by genetic sex and in utero gonadal hormone secretions. In humans however, determining the weight that each of these factors contributes remains a challenge because social influences should also be considered. Cases of disorders of sex development (DSD) provide unique insight into how mutations in genes responsible for gonadal formation can perturb the subsequent developmental hormonal milieu and elicit changes in normal human brain maturation. Specific forms of DSDs such as complete androgen insensitivity syndrome (CAIS), congenital adrenal hyperplasia (CAH), and 5α-reductase deficiency syndrome have variable effects between males and females, and the developmental outcomes of such conditions are largely dependent on sex chromosome composition. Medical and psychological works focused on CAH, CAIS, and 5α-reductase deficiency have helped form the foundation for understanding the roles of genetic and hormonal factors necessary for guiding human brain development. Here we highlight how the three aforementioned DSDs contribute to brain and behavioral phenotypes that can uniquely affect 46,XY and 46,XX individuals in dramatically different fashions. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Zhou, Yuehui; Zhao, Min; Zhou, Chenglin; Li, Rena
Accumulated research supports the idea that exercise could be an option of potential prevention and treatment for drug addiction. During the past few years, there has been increased interest in investigating of sex differences in exercise and drug addiction. This demonstrates that sex-specific exercise intervention strategies may be important for preventing and treating drug addiction in men and women. However, little is known about how and why sex differences are found when doing exercise-induced interventions for drug addiction. In this review, we included both animal and human that pulled subjects from a varied age demographic, as well as neurobiological mechanisms that may highlight the sex-related differences in these potential to assess the impact of sex-specific roles in drug addiction and exercise therapies. Copyright © 2015 Elsevier Inc. All rights reserved.
Zhou, Yuehui; Zhao, Min; Zhou, Chenglin; Li, Rena
Accumulated research supports the idea that exercise could be an option of potential prevention and treatment for drug addiction. During the past few years, there has been increased interest in investigating of sex differences in exercise and drug addiction. This demonstrates that sex-specific exercise intervention strategies may be important for preventing and treating drug addiction in men and women. However, little is known about how and why sex differences are found when doing exercise-induced interventions for drug addiction. In this review, we included both animal and human that pulled subjects from a varied age demographic, as well as neurobiological mechanisms that may highlight the sex-related differences in these potential to assess the impact of sex-specific roles in drug addiction and exercise therapies. PMID:26182835
Roth, Megan E; Cosgrove, Kelly P; Carroll, Marilyn E
Clinical and preclinical findings indicate that males and females differ on several aspects of drug reinforcement. Females are more vulnerable than males during transition periods of drug use that are characteristic of drug addiction and relapse. Females are also more sensitive than males to the reinforcing effects of stimulants. It has been suggested that ovarian hormones contribute to the mechanisms of action underlying these sex differences. This review examines the preclinical literature on sex differences and ovarian hormonal influences on drug self-administration in animals. It summarizes the findings on the effects of these variables during different phases of drug addiction. Possible differences in the mechanisms of action of drugs of abuse due to interactions with sex differences or ovarian hormonal factors are considered. The animal literature on sex differences in drug abuse treatment effectiveness is also discussed.
Beckman, Adam L.; Bucholz, Emily M.; Zhang, Weiwei; Xu, Xiao; Dreyer, Rachel P.; Strait, Kelly M.; Spertus, John A.; Krumholz, Harlan M.; Spatz, Erica S.
Background Financial barriers to health care are associated with worse outcomes following acute myocardial infarction (AMI). Yet, it is unknown whether the prevalence of financial barriers and their relationship with post?AMI outcomes vary by sex among young adults. Methods and Results We assessed sex differences in patient?reported financial barriers among adults aged
Bauermeister, José A; Zimmerman, Marc; Xue, Yange; Gee, Gilbert C; Caldwell, Cleopatra H
Participation in the workplace has been proposed as a potential structural-level HIV/STI prevention strategy for youth. Only a few cross-sectional studies have explored the effect of work during adolescence and young adulthood on sexual behavior and their results have been mixed. This study builds on this literature by exploring whether work influences youths' sexual behavior in a cohort of African American youth (N = 562; 45% males; M = 14.5 years, SD = 0.6) followed from adolescence to young adulthood (ages 13-25 years). Using growth curve modeling, we tested whether working was associated with older sex partners. Then, we explored the association between sex partner age differences and sexual behaviors (i.e., number of sex partners, condom use, and frequency of sexual intercourse). Finally, we tested whether the relationship between sex partner age differences and sexual behaviors was confounded by working. Working greater number of hours was not significantly associated with having older sex partners. Sex partner age differences was associated with number of partners, condom use, and higher sex frequency. These associations were larger for females. Working was associated with higher sex frequency, after accounting for age differences. We discuss the implications of these findings for future research and program planning, particularly in the context of youth development programs.
Swami, Viren; Furnham, Adrian
The present study examined inter-ethnic, rural-urban, and sex differences in self-assessed intelligence (SAI) in a Malaysian general population sample. In total, 633 individuals varying in rural or urban location, ethnicity (Malay, Kadazan, and Bajau), and sex (women versus men) provided their self-assessed overall intelligence and ten multiple…
Constantino, John N.
In this issue of "Autism," new evidence for the equivalency of symptom burden and structure among males and females affected by autism spectrum disorder (ASD) continues to move the spotlight from a notion that the sex ratio in ASD results from the condition being somehow different between the sexes, to the more likely scenario that males…
Kite, Mary E.; Whitley, Bernard E., Jr.
Used meta-analytic techniques to compare men's and women's attitudes toward homosexual persons, homosexual behaviors, and gay people's civil rights. As expected, size of sex differences varied across these categories. Men were more negative than women toward homosexual persons and homosexual behavior, but the sexes viewed gay civil rights…
Bornstein, Robert F.
A meta-analysis of 97 studies published since 1950 that assessed sex differences in scores on objective and projective dependency tests indicated that women consistently obtained higher dependency scores on objective tests, and men obtained higher scores on projective tests. Findings are discussed in terms of sex role socialization. (SLD)
Inglis, James; Lawson, J. S.
A sexual dimorphism in the functional asymmetry of the damaged human brain is reflected in a test-specific laterality effect in male but not in female patients. This sex difference explains some contradictions concerning the effects of unilateral brain damage on intelligence in studies in which the influence of sex was overlooked.
Cox, Brittney M; Young, Amy B; See, Ronald E; Reichel, Carmela M
Previous evidence in an animal model of drug self-administration and drug seeking showed that acute oxytocin decreased methamphetamine (meth) seeking in male rats, suggesting potential clinical efficacy for the treatment of psychostimulant addiction. However, based on the well-established role of oxytocin in reproduction and pair bond formation, it is important to know how this effect extrapolates to females. Here, we tested whether oxytocin (1mg/kg, IP) would decrease meth seeking in female rats across various stages of the estrous cycle (Experiment 1). Freely cycling Long Evans female rats self-administered meth (IV) in 2-h daily sessions, followed by daily extinction sessions. Following extinction, rats received oxytocin (0, 0.3, or 1mg/kg, IP) 30min before a meth priming injection (1mg/kg, IP) to assess reinstatement of meth seeking. Next, we examined the effects of oxytocin on motivated meth- and sucrose-taking and seeking in male and female rats. In separate experiments, males and females self-administered meth (Experiment 2) or sucrose (Experiment 3) until responding was stabilized along a fixed ratio (FR) 5 schedule of reinforcement. Subsequently, rats received either oxytocin or vehicle prior to self-administration along a progressive ratio (PR) schedule of reinforcement. Rats were subsequently tested for cue-, meth-, and stress-induced reinstatement after pretreatment with oxytocin or vehicle. While oxytocin reduced meth seeking in females, we found that estrous cycle stage (as determined from vaginal cytology) did not influence meth-primed reinstatement or the ability of oxytocin to decrease reinstatement of meth seeking. Oxytocin reduced PR responding for meth only in females. Females responded more than males during cue-induced reinstatement of meth and sucrose seeking, and oxytocin reduced this responding only in meth females. In both sexes, oxytocin attenuated meth seeking in response to a meth prime and yohimbine (a pharmacological stressor). The
Bangasser, Debra A; Wiersielis, Kimberly R
Rates of post-traumatic stress disorder, panic disorder, and major depression are higher in women than in men. Another shared feature of these disorders is that dysregulation of the stress neuropeptide, corticotropin-releasing factor (CRF), is thought to contribute to their pathophysiology. Therefore, sex differences in responses to CRF could contribute to this sex bias in disease prevalence. Here, we review emerging data from non-human animal models that reveal extensive sex differences in CRF functions ranging from its presynaptic regulation to its postsynaptic efficacy. Specifically, detailed are sex differences in the regulation of CRF-containing neurons and the amount of CRF that they produce. We also describe sex differences in CRF receptor expression, distribution, trafficking, and signaling. Finally, we highlight sex differences in the processes that mitigate the effects of CRF. In most cases, the identified sex differences can lead to increased stress sensitivity in females. Thus, the relevance of these differences for the increased risk of depression and anxiety disorders in women compared to men is also discussed.
Madenjian, C.P.; Stapanian, M.A.; Rediske, R.R.; O’Keefe, J. P.
Whole-fish polychlorinated biphenyl (PCB) concentrations were determined for 25 female and 25 male burbot Lota lota from Lake Erie. Bioenergetics modeling was used to investigate whether the sex difference in growth rate resulted in a difference in gross growth efficiency (GGE) between the sexes. For ages 6–13 years, male burbot averaged 28 % greater PCB concentrations than female burbot. The sex difference in PCB concentrations widened for ages 14–17 years, with male burbot having, on average, 71 % greater PCB concentrations than female burbot. Bioenergetics modeling results showed that the faster growth rate exhibited by female burbot did not lead to greater GGE in female individuals of the younger burbot and that the faster growth by female fish led to female GGE being only 2 % greater than male GGE in older burbot. Although our bioenergetics modeling could not explain the observed sex difference in PCB concentrations, we concluded that a sex difference in GGE was the most plausible explanation for the sex difference in PCB concentrations of burbot ages 6–13 years. Not only are male fish likely to be more active than female fish, but the resting metabolic rate of male fish may be greater than that of female fish. We also concluded that the widening of the sex difference in PCB concentrations for the older burbot may be due to many of the older male burbot spending a substantial amount of time in the vicinity of mouths of rivers contaminated with PCBs.
Tsujimura, Akira; Miyagawa, Yasushi; Takada, Shingo; Matsuoka, Yasuhiro; Takao, Tetsuya; Hirai, Toshiaki; Matsushita, Masateru; Nonomura, Norio; Okuyama, Akihiko
Although men appear to be more interested in sexual stimuli than women, this difference is not completely understood. Eye-tracking technology has been used to investigate visual attention to still sexual images; however, it has not been applied to moving sexual images. To investigate whether sex difference exists in visual attention to sexual videos. Eleven male and 11 female healthy volunteers were studied by our new methodology. The subjects viewed two sexual videos (one depicting sexual intercourse and one not) in which several regions were designated for eye-gaze analysis in each frame. Visual attention was measured across each designated region according to gaze duration. Sex differences, the region attracting the most attention, and visually favored sex were evaluated. In the nonintercourse clip, gaze time for the face and body of the actress was significantly shorter among women than among men. Gaze time for the face and body of the actor and nonhuman regions was significantly longer for women than men. The region attracting the most attention was the face of the actress for both men and women. Men viewed the opposite sex for a significantly longer period than did women, and women viewed their own sex for a significantly longer period than did men. However, gaze times for the clip showing intercourse were not significantly different between sexes. A sex difference existed in visual attention to a sexual video without heterosexual intercourse; men viewed the opposite sex for longer periods than did women, and women viewed the same sex for longer periods than did men. There was no statistically significant sex difference in viewing patterns in a sexual video showing heterosexual intercourse, and we speculate that men and women may have similar visual attention patterns if the sexual stimuli are sufficiently explicit.
Wallace, Jenna Lee
In Australia, girls continue to be outperformed by boys on large scale mathematics tests. One explanation provided in the literature for this gender gap is the interaction between teacher and student in the classroom. This study was inspired by the persistent patterns of gender differences in mathematics achievement favouring boys at the participating school, a large independent school in Victoria, Australia. In this study, the aim was to determine whether the sex of the mathematics teacher h...
The current study is an investigation of the relationship between the appraisal of traumatic events and mental disorder symptoms: internalizing symptoms and externalizing/substance-abuse symptoms. Cumulative trauma over the lifetime was taken into account. Also, specific effects related to traumatic events of various types (i.e., betrayal trauma, accident involving a family member, physical violence, and natural disaster) were assessed. Participants, 190 young men and 277 young women, were asked to evaluate the strength with which the traumatic event impacted their lives. It was hypothesized that the relationship between traumatic experiences and mental disorder symptoms would be stronger in women than in men, and also that cognitive appraisal, in interaction with gender, would be related to the severity of the symptoms. Women showed higher levels of internalizing symptoms, but lower levels of externalizing/substance-abuse symptoms than men. Still, the correlation between cumulative trauma and both types of symptoms was stronger in women. For all types of trauma, women reported a stronger negative appraisal of the event than men. Interaction of sex and cognitive appraisal was demonstrated to be related to the severity of internalizing disorders. In the present study, women, as compared with men, evaluated traumatic events more negatively (for all types of trauma) and the relationship between trauma and mental disorder symptoms was also stronger in women. These results show the importance of the appraisal of trauma in the development of psychiatric symptoms in women and men following trauma. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
Gordon, Elizabeth A.; Corbitt, Cynthia
Sex differences in social behaviors exist in mammals during adulthood, and further evidence suggests that sex differences in behavior are present before sexual maturity. In order to model behavioral disorders in animals, it is important to assess baseline sex-related behavioral differences, especially when studying disorders for which sex-related behavioral effects are expected. We investigated the effect of sex on behavior in 3 strains of pre-pubertal mice (C57BL/6, CFW, and CF1) using a whe...
Dijkstra, Jan Kornelis; Berger, Christian
The present study examined to what extent selection and influence processes for physical aggression and prosociality in friendship networks differed between sex-specific contexts (i.e., all-male, all-female, and mixed-sex classrooms), while controlling for perceived popularity. Whereas selection processes reflect how behaviors shape friendships, influence processes reveal the reversed pattern by indicating how friends affect individual behaviors. Data were derived from a longitudinal sample of early adolescents from Chile. Four all-male classrooms ( n = 150 male adolescents), four all-female classrooms ( n = 190 female adolescents), and eight mixed-sex classrooms ( n = 272 students) were followed one year from grades 5 to 6 ( M age = 13). Analyses were conducted by means of stochastic-actor-based modeling as implemented in RSIENA. Although it was expected that selection and influence effects for physical aggression and prosociality would vary by context, these effects showed remarkably similar trends across all-male, all-female, and mixed-sex classrooms, with physical aggression reducing and with prosociality increasing the number of nominations received as best friend in all-male and particularly all-female classrooms. Further, perceived popularity increased the number of friendship nominations received in all contexts. Influence processes were only found for perceived popularity, but not for physical aggression and prosociality in any of the three contexts. Together, these findings highlight the importance of both behaviors for friendship selection independent of sex-specific contexts, attenuating the implications of these gendered behaviors for peer relations.
Piccardi, Laura; Bianchini, Filippo; Iasevoli, Luigi; Giannone, Gianluca; Guariglia, Cecilia
Sex differences are consistently reported in human navigation. Indeed, to orient themselves during navigation women are more likely to use landmark-based strategies and men Euclidean-based strategies. The difference could be due to selective social pressure, which fosters greater spatial ability in men, or biological factors. And the great variability of the results reported in the literature could be due to the experimental setting more than real differences in ability. In this study, navigational behaviour was assessed by means of a place-learning task in which a modified version of the Morris water maze for humans was used to evaluate sex differences. In using landmarks, sex differences emerged only during the learning phase. Although the men were faster than the women in locating the target position, the differences between the sexes disappeared in delayed recall. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.
Megan M. Wickens
Full Text Available Alterations in glutamate, the primary excitatory neurotransmitter in the brain, are implicated in several psychiatric diseases. Many of these psychiatric diseases display epidemiological sex differences, with either males or females exhibiting different symptoms or disease prevalence. However, little work has considered the interaction of disrupted glutamatergic transmission and sex on disease states. This review describes the clinical and preclinical evidence for these sex differences with a focus on two conditions that are more prevalent in women: Alzheimer's disease and major depressive disorder, and three conditions that are more prevalent in men: schizophrenia, autism spectrum disorder, and attention deficit hyperactivity disorder. These studies reveal sex differences at multiple levels in the glutamate system including metabolic markers, receptor levels, genetic interactions, and therapeutic responses to glutamatergic drugs. Our survey of the current literature revealed a considerable need for more evaluations of sex differences in future studies examining the role of the glutamate system in psychiatric disease. Gaining a more thorough understanding of how sex differences in the glutamate system contribute to psychiatric disease could provide novel avenues for the development of sex-specific pharmacotherapies.
Bangasser, Debra A; Wiersielis, Kimberly R; Khantsis, Sabina
Women are more likely than men to suffer from post-traumatic stress disorder (PTSD) and major depression. In addition to their sex bias, these disorders share stress as an etiological factor and hyperarousal as a symptom. Thus, sex differences in brain arousal systems and their regulation by stress could help explain increased vulnerability to these disorders in women. Here we review preclinical studies that have identified sex differences in the locus coeruleus (LC)-norepinephrine (NE) arousal system. First, we detail how structural sex differences in the LC can bias females towards increased arousal in response to emotional events. Second, we highlight studies demonstrating that estrogen can increase NE in LC target regions by enhancing the capacity for NE synthesis, while reducing NE degradation, potentially increasing arousal in females. Third, we review data revealing how sex differences in the stress receptor, corticotropin releasing factor 1 (CRF1), can increase LC neuronal sensitivity to CRF in females compared to males. This effect could translate into hyperarousal in women under conditions of CRF hypersecretion that occur in PTSD and depression. The implications of these sex differences for the treatment of stress-related psychiatric disorders are discussed. Moreover, the value of using information regarding biological sex differences to aid in the development of novel pharmacotherapies to better treat men and women with PTSD and depression is also highlighted. This article is part of a Special Issue entitled SI: Noradrenergic System. Copyright © 2015 Elsevier B.V. All rights reserved.
Golden, Lisa C; Voskuhl, Rhonda
To date, scientific research has often focused on one sex, with assumptions that study of the other sex would yield similar results. However, many diseases affect males and females differently. The sex of a patient can affect the risk for both disease susceptibility and progression. Such differences can be brought to the laboratory bench to be investigated, potentially bringing new treatments back to the clinic. This method of research, known as a "bedside to bench to bedside" approach, has been applied to studying sex differences in multiple sclerosis (MS). Females have greater susceptibly to MS, while males have worse disease progression. These two characteristics of the disease are influenced by the immune system and the nervous system, respectively. Thus, sex differences in each system must be studied. Personalized medicine has been at the forefront of research recently, and studying sex differences in disease fits with this initiative. This review will discuss the known sex differences in MS and highlight how investigating them can lead to new insights and potential treatments for both men and women. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Jenkins, L M; Kendall, A D; Kassel, M T; Patrón, V G; Gowins, J R; Dion, C; Shankman, S A; Weisenbach, S L; Maki, P; Langenecker, S A
Sex differences in emotion processing may play a role in women's increased risk for Major Depressive Disorder (MDD). However, studies of sex differences in brain mechanisms involved in emotion processing in MDD (or interactions of sex and diagnosis) are sparse. We conducted an event-related fMRI study examining the interactive and distinct effects of sex and MDD on neural activity during a facial emotion perception task. To minimize effects of current affective state and cumulative disease burden, we studied participants with remitted MDD (rMDD) who were early in the course of the illness. In total, 88 individuals aged 18-23 participated, including 48 with rMDD (32 female) and 40 healthy controls (HC; 25 female). fMRI revealed an interaction between sex and diagnosis for sad and neutral facial expressions in the superior frontal gyrus and left middle temporal gyrus. Results also revealed an interaction of sex with diagnosis in the amygdala. Data was from two sites, which might increase variability, but it also increases power to examine sex by diagnosis interactions. This study demonstrates the importance of taking sex differences into account when examining potential trait (or scar) mechanisms that could be useful in identifying individuals at-risk for MDD as well as for evaluating potential therapeutic innovations. Copyright © 2017 Elsevier B.V. All rights reserved.
Baker, Joseph M.; Liu, Ning; Cui, Xu; Vrticka, Pascal; Saggar, Manish; Hosseini, S. M. Hadi; Reiss, Allan L.
Researchers from multiple fields have sought to understand how sex moderates human social behavior. While over 50 years of research has revealed differences in cooperation behavior of males and females, the underlying neural correlates of these sex differences have not been explained. A missing and fundamental element of this puzzle is an understanding of how the sex composition of an interacting dyad influences the brain and behavior during cooperation. Using fNIRS-based hyperscanning in 111 same- and mixed-sex dyads, we identified significant behavioral and neural sex-related differences in association with a computer-based cooperation task. Dyads containing at least one male demonstrated significantly higher behavioral performance than female/female dyads. Individual males and females showed significant activation in the right frontopolar and right inferior prefrontal cortices, although this activation was greater in females compared to males. Female/female dyad’s exhibited significant inter-brain coherence within the right temporal cortex, while significant coherence in male/male dyads occurred in the right inferior prefrontal cortex. Significant coherence was not observed in mixed-sex dyads. Finally, for same-sex dyads only, task-related inter-brain coherence was positively correlated with cooperation task performance. Our results highlight multiple important and previously undetected influences of sex on concurrent neural and behavioral signatures of cooperation. PMID:27270754
Cosgrove, Kelly P; Mazure, Carolyn M; Staley, Julie K
Clinical and epidemiologic evidence demonstrates sex differences in the prevalence and course of various psychiatric disorders. Understanding sex-specific brain differences in healthy individuals is a critical first step toward understanding sex-specific expression of psychiatric disorders. Here, we evaluate evidence on sex differences in brain structure, chemistry, and function using imaging methodologies, including functional magnetic resonance imaging (fMRI), positron emission tomography (PET), single photon emission computed tomography (SPECT), and structural magnetic resonance imaging (MRI) in mentally healthy individuals. MEDLINE searches of English-language literature (1980-November 2006) using the terms sex, gender, PET, SPECT, MRI, fMRI, morphometry, neurochemistry, and neurotransmission were performed to extract relevant sources. The literature suggests that while there are many similarities in brain structure, function, and neurotransmission in healthy men and women, there are important differences that distinguish the male from the female brain. Overall, brain volume is greater in men than women; yet, when controlling for total volume, women have a higher percentage of gray matter and men a higher percentage of white matter. Regional volume differences are less consistent. Global cerebral blood flow is higher in women than in men. Sex-specific differences in dopaminergic, serotonergic, and gamma-aminobutyric acid (GABA)ergic markers indicate that male and female brains are neurochemically distinct. Insight into the etiology of sex differences in the normal living human brain provides an important foundation to delineate the pathophysiological mechanisms underlying sex differences in neuropsychiatric disorders and to guide the development of sex-specific treatments for these devastating brain disorders.
Renate B. Schnabel
Full Text Available Background-There are marked sex differences in cardiovascular disease [CVD] manifestation. It is largely unknown how the distribution of CVD risk factors or intermediate phenotypes explain sex-specific differences.Methods and Results-In 5000 individuals of the population-based Gutenberg Health Study, mean age 55±11 years, 51% males, we examined sex-specific associations of classical CVD risk factors with intima-media thickness, ankle-brachial index, flow-mediated dilation, peripheral arterial tonometry, echocardiographic and electrocardiographic variables. Intermediate cardiovascular phenotypes were related to prevalent CVD (coronary artery disease, heart failure, stroke, myocardial infarction, lower extremity artery disease [LEAD] N=561.We observed differential distributions of CVD risk factors with a higher risk factor burden in men. Manifest coronary artery disease, stroke, myocardial infarction and LEAD were more frequent in men; the proportion of heart failure was higher in women. Intermediate phenotypes showed clear sex differences with more beneficial values in women. Fairly linear changes towards less beneficial values with age were observed in both sexes. In multivariable-adjusted regression analyses age, systolic blood pressure and body mass index were consistently associated with intermediate phenotypes in both sexes with different ranking according to random forests, maximum model R² 0.43. Risk factor-adjusted associations with prevalent CVD showed some differences by sex. No interactions by menopausal status were observed. Conclusions-In a population-based cohort we observed sex differences in risk factors and a broad range of intermediate phenotypes of noninvasive cardiovascular structure and function. Their relation to prevalent CVD differed markedly. Our results indicate the need of future investigations to understand sex differences in CVD manifestation.
Sarah L. Strout; James D. Laird; Aaron Shafer; Nicholas S. Thompson
Doubt has been raised about the validity of results that appear to demonstrate sex differences in the type of infidelity that elicits jealousy. Two studies explored proposed methodological weaknesses of this research. The first study distinguished participants who had experienced infidelity and those who had only imagined infidelity. The study found the classic sex differences when participants were “forced” to choose which kind of infidelity would be most upsetting, and these differences wer...
Cramer, Robert Ervin; Lipinski, Ryan E; Meteer, John D; Houska, Jeremy Ashton
According to an evolutionary psychology perspective, men's and women's processing of threats to their sex-linked mate selection strategies cause sex differences in infidelity distress. An alternative account assumes that the distress results from men's and women's processing of expectation violations regarding the content of an unfaithful partner's actions with a rival. Logistic regressions supported the conclusion that the participant's sex-but not the processing of expectation violations-was the best predictor of the most distressing infidelity presented in forced-choice, mutually exclusive, and combined formats. Our results also indicated that the sex differences in infidelity distress were neither limited to using data from a forced-choice response format nor caused by the distinct inferences that men and women draw about the relation between love and sex.
Ter Horst, Gert J.; Wichmann, Romy; Gerrits, Marjolein; Westenbroek, Christel; Lin, Yanhua
Women in the reproductive age are more vulnerable to develop affective disorders than men. This difference may attribute to anatomical differences, hormonal influences and environmental factors such as stress. However, the higher prevalence in women normalizes once menopause is established,
Full Text Available The blue-gum chalcid Leptocybe invasa Fisher & LaSalle (Hymenoptera: Eulophidae is a gall wasp pest of Eucalyptus species, likely native to Australia. Over the past 15 years it has invaded 39 countries on all continents where eucalypts are grown. The worldwide invasion of the blue gum chalcid was attributed to a single thelytokous morphospecies formally described in 2004. Subsequently, however, males have been recorded in several countries and the sex ratio of field populations has been found to be highly variable in different areas. In order to find an explanation for such sex ratio differences, populations of L. invasa from a broad geographical area were screened for the symbionts currently known as reproductive manipulators, and both wasps and symbionts were genetically characterized using multiple genes. Molecular analyses suggested that L. invasa is in fact a complex of two cryptic species involved in the rapid and efficient spread of the wasp, the first recovered from the Mediterranean region and South America, the latter from China. All screened specimens were infected by endosymbiotic bacteria belonging to the genus Rickettsia. Two closely related Rickettsia strains were found, each infecting one of the two putative cryptic species of L. invasa and associated with different average sex ratios. Rickettsia were found to be localized in the female reproductive tissues and transovarially transmitted, suggesting a possible role of Rickettsia as the causal agent of thelytokous parthenogenesis in L. invasa. Implications for the variation of sex ratio and for the management of L. invasa are discussed.
Nugnes, Francesco; Gebiola, Marco; Monti, Maurilia Maria; Gualtieri, Liberata; Giorgini, Massimo; Wang, Jianguo; Bernardo, Umberto
The blue-gum chalcid Leptocybe invasa Fisher & LaSalle (Hymenoptera: Eulophidae) is a gall wasp pest of Eucalyptus species, likely native to Australia. Over the past 15 years it has invaded 39 countries on all continents where eucalypts are grown. The worldwide invasion of the blue gum chalcid was attributed to a single thelytokous morphospecies formally described in 2004. Subsequently, however, males have been recorded in several countries and the sex ratio of field populations has been found to be highly variable in different areas. In order to find an explanation for such sex ratio differences, populations of L. invasa from a broad geographical area were screened for the symbionts currently known as reproductive manipulators, and both wasps and symbionts were genetically characterized using multiple genes. Molecular analyses suggested that L. invasa is in fact a complex of two cryptic species involved in the rapid and efficient spread of the wasp, the first recovered from the Mediterranean region and South America, the latter from China. All screened specimens were infected by endosymbiotic bacteria belonging to the genus Rickettsia. Two closely related Rickettsia strains were found, each infecting one of the two putative cryptic species of L. invasa and associated with different average sex ratios. Rickettsia were found to be localized in the female reproductive tissues and transovarially transmitted, suggesting a possible role of Rickettsia as the causal agent of thelytokous parthenogenesis in L. invasa. Implications for the variation of sex ratio and for the management of L. invasa are discussed. PMID:25970681
Mitchell, Jason W
Prior studies with men who have sex with men have documented a strong association between substance use with sex and risk for acquisition of HIV. However, few studies have been conducted about gay male couples' use of substances with sex, despite the fact that between one third and two thirds of men who have sex with men acquire HIV from their relationship partners. The present study sought to (1) describe whether one or both partners in the male couple uses substances with sex-by substance type-within and/or outside of their relationship, and (2) assess whether differences exist in those who use substances with sex within and outside the relationship by the couples' HIV status. Dyadic data for this analysis were collected in the United States from a nation-wide cross-sectional Internet study about male couples' relationships and behaviors. Couple-level descriptive and comparative analyses were employed with 361 male couples. Except for alcohol, most couples did not use substances with sex. Of those who did, rates of who used it with sex and substance type within the relationship varied; most couples only had one partner who used substances with sex outside the relationship. Significantly higher proportions of concordantly HIV-negative and HIV-positive couples had both partners who used substances (all types) with sex within their relationship over discordant couples. Most couples had one partner who used outside the relationship; only marijuana and erectile dysfunction medication use with sex significantly differed by couples' HIV status. Findings indicate the need to conduct additional research for prevention development. © The Author(s) 2014.
Bedford, Rachael; Jones, Emily J H; Johnson, Mark H; Pickles, Andrew; Charman, Tony; Gliga, Teodora
Although it is well established that the prevalence of autism spectrum disorder (ASD) is higher in males than females, there is relatively little understanding of the underlying mechanisms and their developmental time course. Sex-specific protective or risk factors have often been invoked to explain these differences, but such factors are yet to be identified. We take a developmental approach, using a prospective sample of 104 infants at high and low familial risk for ASD, to characterise sex differences in infant markers known to predict emerging autism symptoms. We examine three markers previously shown to be associated with later autistic social-communication symptoms: the Autism Observation Scale for Infants (AOSI) total score, attention disengagement speed and gaze following behaviour. Our aim was to test whether sex differences were already present in these markers at 1 year of age, which would suggest sex-specific mechanisms of risk or protection. While no sex differences were found in any of the three markers investigated, we found sex differences in their relationship to 3-year autism traits; all three markers significantly predicted later autism traits only in the boys. Previously identified 'early autism markers' were associated with later autism symptoms only in boys. This suggests that there may be additional moderating risk or protective factors which remain to be identified. Our findings have important implications for prospective studies in terms of directly testing for the moderating effect of sex on emerging autistic traits.
Niveditha, S; Deepashree, S; Ramesh, S R; Shivanandappa, T
Gender differences in lifespan and aging are known across species. Sex differences in longevity within a species can be useful to understand sex-specific aging. Drosophila melanogaster is a good model to study the problem of sex differences in longevity since females are longer lived than males. There is evidence that stress resistance influences longevity. The objective of this study was to investigate if there is a relationship between sex differences in longevity and oxidative stress resistance in D. melanogaster. We observed a progressive age-dependent decrease in the activity of SOD and catalase, major antioxidant enzymes involved in defense mechanisms against oxidative stress in parallel to the increased ROS levels over time. Longer-lived females showed lower ROS levels and higher antioxidant enzymes than males as a function of age. Using ethanol as a stressor, we have shown differential susceptibility of the sexes to ethanol wherein females exhibited higher resistance to ethanol-induced mortality and locomotor behavior compared to males. Our results show strong correlation between sex differences in oxidative stress resistance, antioxidant defenses and longevity. The study suggests that higher antioxidant defenses in females may confer resistance to oxidative stress, which could be a factor that influences sex-specific aging in D. melanogaster.
Taylor, Marcus K; Larson, Gerald E; Hiller Lauby, Melissa D; Padilla, Genieleah A; Wilson, Ingrid E; Schmied, Emily A; Highfill-McRoy, Robyn M; Morgan, Charles A
Evidence points to heightened physiological arousal in response to acute stress exposure as both a prospective indicator and a core characteristic of posttraumatic stress disorder (PTSD). Because females may be at higher risk for PTSD development, it is important to evaluate sex differences in acute stress reactions. This study characterized sex differences in cardiovascular and subjective stress reactions among military survival trainees. One hundred and eighty-five military members (78% males) were studied before, during, and 24 h after stressful mock captivity. Cardiovascular (heart rate [HR], systolic blood pressure [SBP], diastolic blood pressure [DBP]) and dissociative states were measured at all three time points. Psychological impact of mock captivity was assessed during recovery. General linear modeling with repeated measures evaluated sex differences for each cardiovascular endpoint, and causal steps modeling was used to explore interrelationships among sex, cardiovascular reactions and psychological impact of mock captivity. Although females had lower SBP than males at all three time points, the difference was most pronounced at baseline and during stress. Accordingly, females showed greater residual elevation in SBP during recovery. Females had lower DBP at all three time points. In addition, females reported greater psychological impact of mock captivity than males. Exploratory causal steps modeling suggested that stress-induced HR may partially mediate the effect of sex on psychological impact of mock captivity. In conclusion, this study demonstrated sex-specific cardiovascular stress reactions in military personnel, along with greater psychological impact of stress exposure in females. This research may elucidate sex differences in PTSD development.
Ruigrok, Amber N V; Salimi-Khorshidi, Gholamreza; Lai, Meng-Chuan; Baron-Cohen, Simon; Lombardo, Michael V; Tait, Roger J; Suckling, John
The prevalence, age of onset, and symptomatology of many neuropsychiatric conditions differ between males and females. To understand the causes and consequences of sex differences it is important to establish where they occur in the human brain. We report the first meta-analysis of typical sex differences on global brain volume, a descriptive account of the breakdown of studies of each compartmental volume by six age categories, and whole-brain voxel-wise meta-analyses on brain volume and density. Gaussian-process regression coordinate-based meta-analysis was used to examine sex differences in voxel-based regional volume and density. On average, males have larger total brain volumes than females. Examination of the breakdown of studies providing total volumes by age categories indicated a bias towards the 18-59 year-old category. Regional sex differences in volume and tissue density include the amygdala, hippocampus and insula, areas known to be implicated in sex-biased neuropsychiatric conditions. Together, these results suggest candidate regions for investigating the asymmetric effect that sex has on the developing brain, and for understanding sex-biased neurological and psychiatric conditions. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.
Ruigrok, Amber N.V.; Salimi-Khorshidi, Gholamreza; Lai, Meng-Chuan; Baron-Cohen, Simon; Lombardo, Michael V.; Tait, Roger J.; Suckling, John
The prevalence, age of onset, and symptomatology of many neuropsychiatric conditions differ between males and females. To understand the causes and consequences of sex differences it is important to establish where they occur in the human brain. We report the first meta-analysis of typical sex differences on global brain volume, a descriptive account of the breakdown of studies of each compartmental volume by six age categories, and whole-brain voxel-wise meta-analyses on brain volume and density. Gaussian-process regression coordinate-based meta-analysis was used to examine sex differences in voxel-based regional volume and density. On average, males have larger total brain volumes than females. Examination of the breakdown of studies providing total volumes by age categories indicated a bias towards the 18–59 year-old category. Regional sex differences in volume and tissue density include the amygdala, hippocampus and insula, areas known to be implicated in sex-biased neuropsychiatric conditions. Together, these results suggest candidate regions for investigating the asymmetric effect that sex has on the developing brain, and for understanding sex-biased neurological and psychiatric conditions. PMID:24374381
Okuyama, Kaori; Hamanaka, Yuka; Kawano, Tasuku; Ohkawara, Yuichi; Takayanagi, Motoaki; Kikuchi, Toshiaki; Ohno, Isao
Before puberty, the prevalence and severity of asthma are higher in boys than in girls, but this pattern is reversed after puberty. The underlying mechanisms of these gender differences in asthma are not fully understood. Using murine models of allergic asthma, a sex difference in Th2 cytokine production has been suggested to contribute to the gender differences in asthma. Therefore, we determined which subsets of T cells are involved in the sex difference in Th2 cytokine production. Splenocytes from wild-type mice and CD4+ T cell-, CD8+ T cell-, and iNKT cell-deficient mice were stimulated with anti-CD3/CD28 antibodies for 3 days, and the concentrations of IL-4, IL-5, IL-13, and IFN-γ in the cultures were measured by ELISA. IL-5, but not IL-4 and IL-13, concentrations in culture derived from female wild-type mice were significantly higher than those in male wild-type mice. The sex difference in IL-5 concentrations was not observed in the cultures of splenocytes from CD4+ and CD8+ T cell-deficient mice. The disappearance of the sex differences in CD4+ and CD8+ T cell-deficient mice was attributable to a decrease in IL-5 concentration in female mice and an increase in IL-5 concentration in male mice. In iNKT cell-deficient mice, the sex difference was still observed. There was no significant difference between the sexes in any type of mice with respect to IFN-γ production. There was a sex difference in IL-5 production by splenocytes stimulated by TCR activation. The difference might be attributable to sex differences in CD4+ and CD8+ T cell functions. Copyright © 2011 S. Karger AG, Basel.
Kilpatrick, L A; Zald, D H; Pardo, J V; Cahill, L F
Recent neuroimaging studies have established a sex-related hemispheric lateralization of amygdala involvement in memory for emotionally arousing material. Here, we examine the possibility that sex-related differences in amygdala involvement in memory for emotional material develop from differential patterns of amygdala functional connectivity evident in the resting brain. Seed voxel partial least square analyses of regional cerebral blood flow data revealed significant sex-related differences in amygdala functional connectivity during resting conditions. The right amygdala was associated with greater functional connectivity in men than in women. In contrast, the left amygdala was associated with greater functional connectivity in women than in men. Furthermore, the regions displaying stronger functional connectivity with the right amygdala in males (sensorimotor cortex, striatum, pulvinar) differed from those displaying stronger functional connectivity with the left amygdala in females (subgenual cortex, hypothalamus). These differences in functional connectivity at rest may link to sex-related differences in medical and psychiatric disorders.
Gale, William L.; Patino, Reynaldo; Maule, Alec G.
Estrogens are important regulators of physiological functions. Although environmental contaminants (xenoestrogens) which interfere with estrogen signaling are of increasing concern, there is only limited information about their ability to interact with estrogen-binding proteins (SHBG) or receptors (ER). Recombinant ER?? and ?? were obtained after transient transfection of COS-7 cells with channel catfish ER cDNA. Plasma from adult female channel catfish was the source of SHBG. Tritiated estradiol ( 3H-E2) was used in standard radioligand-binding assays to characterize the binding properties of channel catfish SHBG (ccfSHBG) and to estimate the inhibition constants for various estrogenic compounds. Binding of 3H-E2 to ccfSHBG was saturable and of high affinity with a Kd (??SE) of 1.9??0.14nM and a Bmax of 14.3??2.4pmol/mg protein (n=3 assays). Additionally, ccfSHBG displayed binding specificity for androgens and estrogens. Endosulfan, 4-nonylphenol, and 4-octylphenol displaced 3H-E2 binding to ccfSHBG albeit only at very high concentrations, whereas dieldrin and atrazine showed little displacement activity even at the highest concentrations used. The synthetic estrogen ethynylestradiol had higher affinity than E2 for ccfSHBG. This finding differs from results with human and rainbow trout SHBG. The alkylphenolic compounds (4-octylphenol and 4-nonylphenol) displayed some ability to displace 3H-E2 binding from ER?? and ?? at high concentrations, but dieldrin and atrazine had little binding activity for both ER subtypes and endosulfan for ER??. The xenobiotics tested generally showed equivalent or greater affinity for ER?? than ER??, whereas natural estrogens had much greater affinity for ER?? than ER??. These observations suggest that results of studies using fish tissue ER extracts must be interpreted with caution, since both ER subtypes may be present, and that the binding of xenoestrogens to SHBG must be taken into account for proper assessment of endocrine
Although the link between sex and attachment was made decades ago (Hazan & Shaver, 1987), theories on sexual and attachment functioning have been developed in relative isolation. Recent efforts to integrate both literatures have been complicated by the fact that the sex-attachment link has been approached from very different perspectives, including biological, evolutionary, developmental, cognitive, and social psychology approaches. Also, at the empirical level, research on sex and attachment lacks overarching synthesis. This article gives an overview of the most important theoretical ideas and empirical insights on sex and attachment. It starts with describing general models that approach the sex-attachment link from an evolutionary and neurobiological perspective. Then, it summarizes theoretical and empirical ideas of attachment theory and describes how attachment style differences are manifested in intimate and sexual relationships. Research so far has been limited to studying the predicted link between sex and attachment in terms of broad descriptives, and it would benefit the literature to specify the processes and pathways that mediate the sex-attachment link. After a short discussion of the functional similarities between the sexual and the attachment systems, the article describes some specific--dynamical--models that focus on the emotional and cognitive-motivational processes through which attachment schemas influence sexual experiences. Such an emotion-motivational perspective on sex and attachment can help to organize theoretical ideas and empirical findings and eventually promote an integrative view on how attachment dynamics can interact with sexual experiences.
Full Text Available Sex-based differences in human susceptibility to cardiac ventricular tachyarrhythmias likely result from the emergent effects of multiple intersecting processes that fundamentally differ in male and female hearts. Included are measured differences in the genes encoding key cardiac ion channels and effects of sex steroid hormones to acutely modify electrical activity. At the genome scale, human females have recently been shown to have lower expression of genes encoding key cardiac repolarizing potassium currents and connexin43, the primary ventricular gap junction subunit. Human males and females also have distinct sex steroid hormones. Here, we developed mathematical models for male and female ventricular human heart cells by incorporating experimentally determined genomic differences and effects of sex steroid hormones into the O’Hara-Rudy model. These male and female model cells and tissues then were used to predict how various sex-based differences underlie arrhythmia risk. Genomic-based differences in ion channel expression were alone sufficient to determine longer female cardiac action potential durations (APD in both epicardial and endocardial cells compared to males. Subsequent addition of sex steroid hormones exacerbated these differences, as testosterone further shortened APDs, while estrogen and progesterone application resulted in disparate effects on APDs. Our results indicate that incorporation of experimentally determined genomic differences from human hearts in conjunction with sex steroid hormones are consistent with clinically observed differences in QT interval, T-wave shape and morphology, and critically, in the higher vulnerability of adult human females to Torsades de Pointes type arrhythmias. The model suggests that female susceptibility to alternans stems from longer female action potentials, while reentrant arrhythmia derives largely from sex-based differences in conduction play an important role in arrhythmia
Jadva, Vasanti; Hines, Melissa; Golombok, Susan
Girls and boys differ in their preferences for toys such as dolls and trucks. These sex differences are present in infants, are seen in non-human primates, and relate, in part, to prenatal androgen exposure. This evidence of inborn influences on sex-typed toy preferences has led to suggestions that object features, such as the color or the shape of toys, may be of intrinsically different interest to males and females. We used a preferential looking task to examine preferences for different toys, colors, and shapes in 120 infants, ages 12, 18, or 24 months. Girls looked at dolls significantly more than boys did and boys looked at cars significantly more than girls did, irrespective of color, particularly when brightness was controlled. These outcomes did not vary with age. There were no significant sex differences in infants' preferences for different colors or shapes. Instead, both girls and boys preferred reddish colors over blue and rounded over angular shapes. These findings augment prior evidence of sex-typed toy preferences in infants, but suggest that color and shape do not determine these sex differences. In fact, the direction of influence could be the opposite. Girls may learn to prefer pink, for instance, because the toys that they enjoy playing with are often colored pink. Regarding within sex differences, as opposed to differences between boys and girls, both boys and girls preferred dolls to cars at age 12-months. The preference of young boys for dolls over cars suggests that older boys' avoidance of dolls may be acquired. Similarly, the sex similarities in infants' preferences for colors and shapes suggest that any subsequent sex differences in these preferences may arise from socialization or cognitive gender development rather than inborn factors.
Wheaton, Felicia V; Crimmins, Eileen M
The objectives were to determine whether women always fare more poorly in terms of physical function and disability across countries that vary widely in terms of their level of development, epidemiologic context and level of gender equality. Sex differences in self-reported and objective measures of disability and physical function were compared among older adults aged 55-85 in the United States of America, Taiwan, Korea, Mexico, China, Indonesia and among the Tsimane of Bolivia using population-based studies collected between 2001 and 2011. Data were analysed using logistic and ordinary least-squares regression. Confidence intervals were examined to see whether the effect of being female differed significantly between countries. In all countries, women had consistently worse physical functioning (both self-reported and objectively measured). Women also tended to report more difficulty with activities of daily living (ADL), although differences were not always significant. In general, sex differences across measures were less pronounced in China. In Korea, women had significantly lower grip strength, but sex differences in ADL difficulty were non-significant or even reversed. Education and marital status helped explain sex differences. Overall, there was striking similarity in the magnitude and direction of sex differences across countries despite considerable differences in context, although modest variations in the effect of sex were observed.
Michelle N. Arbeitman
Full Text Available Sex differences in gene expression have been widely studied in Drosophila melanogaster. Sex differences vary across strains, but many molecular studies focus on only a single strain, or on genes that show sexually dimorphic expression in many strains. How extensive variability is and whether this variability occurs among genes regulated by sex determination hierarchy terminal transcription factors is unknown. To address these questions, we examine differences in sexually dimorphic gene expression between two strains in Drosophila adult head tissues. We also examine gene expression in doublesex (dsx mutant strains to determine which sex-differentially expressed genes are regulated by DSX, and the mode by which DSX regulates expression. We find substantial variation in sex-differential expression. The sets of genes with sexually dimorphic expression in each strain show little overlap. The prevalence of different DSX regulatory modes also varies between the two strains. Neither the patterns of DSX DNA occupancy, nor mode of DSX regulation explain why some genes show consistent sex-differential expression across strains. We find that the genes identified as regulated by DSX in this study are enriched with known sites of DSX DNA occupancy. Finally, we find that sex-differentially expressed genes and genes regulated by DSX are highly enriched on the fourth chromosome. These results provide insights into a more complete pool of potential DSX targets, as well as revealing the molecular flexibility of DSX regulation.
The present study established relationships between individual differences and subjective evaluation of different kinds of landscapes. These were the first three principle components of the five components obtained from a matrix of coincidences. The three components used were: 1) natural versus humanized landscapes; 2) pleasant versus rough landscapes; 3) straight and...
Beauchaine, Theodore P.; Hong, James; Marsh, Penny
The study aims to evaluate group differences in autonomic nervous system (ANS) responding between males and females with conduct problems and determine whether aggression accounts for variance in ANS responding over the effects of conduct problems. The results indicated marked differences in psycho-physiological responses between males and females.
Jena, Anupam B.; Olenski, Andrew R.; Blumenthal, Daniel M.
Importance Limited evidence exists on salary differences between male and female academic physicians, largely due to difficulty obtaining data on salary and factors influencing salary. Existing studies have been limited by reliance on survey-based approaches to measuring sex differences in earnings, lack of contemporary data, small sample sizes, or limited geographic representation. Objective To analyze sex differences in earnings among U.S. academic physicians. Design, setting, and participants Freedom of Information laws mandate release of salary information of public university employees in several states. In 12 states with salary information published online, we extracted salary data on 10,241 academic physicians at 24 public medical schools. We linked this data to a unique physician database with detailed information on sex, age, years of experience, faculty rank, specialty, scientific authorship, NIH funding, clinical trial participation, and Medicare reimbursements (proxy for clinical revenue). We estimated sex differences in salary adjusting for these factors. Exposure Physician sex Main outcome measures Annual salary Results Female physicians had lower unadjusted salaries than male physicians ($206,641 vs. $257,957; difference $51,315; 95% CI $46,330–$56,301). Sex differences persisted after multivariable adjustment ($227,782 vs. $247,661; difference $19,878; 95% CI $15,261–$24,495). Sex differences in salary varied across specialties, institutions, and faculty ranks. Female full and associate professors had comparable adjusted salaries to those of male associate and assistant professors, respectively. Conclusions and relevance Among physicians with faculty appointments at 24 U.S. public medical schools, significant sex differences in salary exist even after accounting for age, experience, specialty, faculty rank, and measures of research productivity and clinical revenue. PMID:27400435
Reysen, Stephen; Reysen, Matthew B
Sex differences in conformity were examined as participants approached two ATMs, one of which was occupied by three confederates and the other immediately available. The number of men and women in the line in front of one of the ATMs was manipulated (3 men or 3 women), and an unobtrusive observer recorded the sex of each participant. The results indicated that women were more likely than men to wait in line to use the ATM regardless of the makeup of the line. Thus, the present study provides evidence in favor of the idea that sex differences in conformity are evident on a common task performed in a natural setting.
Klungel, O.H.; de Boer, A; Paes, A.H.P.; Seidell, J C; Bakker, A
OBJECTIVE: To summarize all available literature on sex differences in the pharmacological treatment of hypertension with respect to the percentage of hypertensive patients treated pharmacologically and the selection of antihypertensive drugs. The influences of the calendar period, age, definition
Full Text Available Although sex difference in the mean level of depressive symptoms has been well established, the sex difference in genetic and environmental influences on adolescent depressive symptoms is unclear. The current study conducted a meta-analysis of twin studies on sex differences in self- and parent-reported adolescent depressive symptoms. For self-reports, genetic factors influenced adolescent depressive symptoms equally for boys and girls, accounting for 46% of variation, but shared environmental factors had stronger impacts on adolescent girls’ versus boys’ depressive symptoms (13% versus 1% of the variance. For parent-reports, genetic, shared, and nonshared environmental factors influenced adolescent depressive symptoms equally, with separate estimates of 34%, 35%, and 31%. The implications of sex difference in genetic and environmental etiologies of depressive symptoms are discussed.
Horiuchi, Tetsuyoshi; Tanaka, Yuichiro; Hongo, Kazuhiro
Sex-related differences were examined in the clinical course of patients treated surgically for aneurysmal subarachnoid hemorrhage. Retrospective analyses were carried out to evaluate sex-related differences in aneurysm location, aneurysm size, preoperative neurological condition, preoperative computed tomography findings, and outcome among 2577 patients who underwent surgical repair of ruptured aneurysms. The internal carotid artery was most frequently affected in women and the anterior cerebral artery in men. Intracerebral or intraventricular hematoma was more common in men than in women. Some differences may be related to the location of the aneurysm. Sex-related differences were prominent in the 5th decade of life. These findings might be related to the menopause. Sex hormones may be involved in aneurysm formation. (author)
Full Text Available We tested the hypothesis that magnitudes of sex differences in human mate preferences would be inversely related to control of resources. Specifically, we predicted that the ideal partner age, maximum and minimum partner ages tolerated and preferences for “physical attractiveness” over “good financial prospects” of female participants would approach parity with that of men with increasing control of resources. In a sample of 3770 participants recruited via an online survey, the magnitudes of sex differences in age preferences increased with resource control whereas the sex difference in preferences for “physical attractiveness” over “good financial prospects” disappeared when resource control was high. Results are inconsistent, and are discussed in the context of adaptive tradeoff and biosocial models of sex differences in human mate preferences.
Conclusions: The results of this study suggest sex differences in structural alterations following exposure to RSHI. Future studies need to investigate further the underlying mechanisms and association with exposure and clinical outcomes.
Full Text Available Sex differences have been previously highlighted in the cardioprotective effects of the Mediterranean diet (MedDiet. The objective of this study was to investigate whether sex differences also exist with regard to LDL particle size distribution and oxidation. Participants were 37 men and 32 premenopausal women (24–53 years with slightly elevated LDL-C concentrations (3.4–4.9 mmol/L or total cholesterol/HDL-C ≥5.0. Variables were measured before and after a four-week isoenergetic MedDiet. Sex differences were found in response to the MedDiet for the proportion of medium LDL (255–260 Å (p for sex-by-time interaction = 0.01 and small, dense LDL (sdLDL; <255 Å (trend; p for sex-by-time interaction = 0.06, men experiencing an increase in the proportion of medium LDL with a concomitant reduction in the proportion of sdLDL, while an opposite trend was observed in women. A sex difference was also noted for estimated cholesterol concentrations among sdLDL (p for sex-by-time interaction = 0.03, with only men experiencing a reduction in response to the MedDiet. The MedDiet marginally reduced oxidized LDL (oxLDL concentrations (p = 0.07, with no sex difference. Results suggest that short-term consumption of the MedDiet leads to a favorable redistribution of LDL subclasses from smaller to larger LDL only in men. These results highlight the importance of considering sex issues in cardiovascular benefits of the MedDiet.
Bédard, Alexandra; Corneau, Louise; Lamarche, Benoît; Dodin, Sylvie; Lemieux, Simone
Sex differences have been previously highlighted in the cardioprotective effects of the Mediterranean diet (MedDiet). The objective of this study was to investigate whether sex differences also exist with regard to LDL particle size distribution and oxidation. Participants were 37 men and 32 premenopausal women (24-53 years) with slightly elevated LDL-C concentrations (3.4-4.9 mmol/L) or total cholesterol/HDL-C ≥5.0. Variables were measured before and after a four-week isoenergetic MedDiet. Sex differences were found in response to the MedDiet for the proportion of medium LDL (255-260 Å) (p for sex-by-time interaction = 0.01) and small, dense LDL (sdLDL; <255 Å) (trend; p for sex-by-time interaction = 0.06), men experiencing an increase in the proportion of medium LDL with a concomitant reduction in the proportion of sdLDL, while an opposite trend was observed in women. A sex difference was also noted for estimated cholesterol concentrations among sdLDL (p for sex-by-time interaction = 0.03), with only men experiencing a reduction in response to the MedDiet. The MedDiet marginally reduced oxidized LDL (oxLDL) concentrations (p = 0.07), with no sex difference. Results suggest that short-term consumption of the MedDiet leads to a favorable redistribution of LDL subclasses from smaller to larger LDL only in men. These results highlight the importance of considering sex issues in cardiovascular benefits of the MedDiet.
Andrews, Paul W; Gangestad, Steven W; Miller, Geoffrey F; Haselton, Martie G; Thornhill, Randy; Neale, Michael C
Despite the importance of extrapair copulation (EPC) in human evolution, almost nothing is known about the design features of EPC detection mechanisms. We tested for sex differences in EPC inference-making mechanisms in a sample of 203 young couples. Men made more accurate inferences (φmen = 0.66, φwomen = 0.46), and the ratio of positive errors to negative errors was higher for men than for women (1.22 vs. 0.18). Since some may have been reluctant to admit EPC behavior, we modeled how underreporting could have influenced these results. These analyses indicated that it would take highly sex-differentiated levels of underreporting by subjects with trusting partners for there to be no real sex difference. Further analyses indicated that men may be less willing to harbor unresolved suspicions about their partners' EPC behavior, which may explain the sex difference in accuracy. Finally, we estimated that women underreported their own EPC behavior (10%) more than men (0%).
Bakula, Dana M; Mullins, Alexandria J; Sharkey, Christina M; Wolfe-Christensen, Cortney; Mullins, Larry L; Wisniewski, Amy B
Disorders/differences of sex development (DSD) comprise multiple congenital conditions in which chromosomal, gonadal, and/or anatomical sex are discordant. The prediction of future gender identity (i.e., self-identifying as male, female, or other) in children with DSD can be imprecise, and current knowledge about the development of gender identity in people with, and without DSD, is limited. However, sex of rearing is the strongest predictor of gender identity for the majority of individuals with various DSD conditions. When making decisions regarding sex of rearing biological factors (e.g., possession of a Y chromosome, degree and duration of pre- and postnatal androgen exposure, phenotypic presentation of the external genitalia, and fertility potential), social and cultural factors, as well as quality of life should be considered. Information on gender identity outcomes across a range of DSD diagnoses is presented to aid in sex of rearing assignment. Copyright © 2017 Elsevier Inc. All rights reserved.
Conclusion: Women need more analgesic agents than men during panendoscopic examination. There was no significant difference between men and women with regard to anesthetic depth and response to noxious stimuli, as revealed by similar SE and RE values.
Irwin, H J
Vitulli, Tipton, and Rowe (1999) report evidence of age and sex differences in the strength of paranormal beliefs. An alternative interpretation of their data is offered in terms of differential item functioning. It is suggested that respondents' interpretation of paranormal belief test items may vary with age and sex, and that such differences in the strength with which such beliefs are endorsed has not been conclusively established by Vitulli, et al.
Quatman, Carmen E.; Myer, Gregory D.; Khoury, Jane; Wall, Eric J.; Hewett, Timothy E.
Benefits of resistance training include improved muscle strength and sports performance, and may include reduced injuries. However, few studies have examined sex differences in resistance training related injuries. The objective of this investigation was to evaluate sex differences in injuries associated with weightlifting, in adolescents and young adults by type (sprains and strains, fractures), mechanism (accidental, non-accidental) and location (head, trunk, arm, hand, leg, foot) of injury...
Bakhiet, Salaheldin F; Albursan, Ismael S; Al Qudah, Mohammad F; Abduljabbar, Adel S; Aljomaa, Suliman S; Toto, Howida Sirelkhatim Abdalrahim; Lynn, Richard
The sex differences on the WISC-III are reported for the thirteen subtests, the Verbal and Performance IQs, the four Index IQs and the Full Scale IQs in Sudan and the United States. The sex differences are closely similar in the two samples with a correlation of 0.878 (p<0.001) for the thirteen subtests. Males obtained significantly higher Full Scale IQs in the two samples of 0.23d and 0.11d, respectively.
Carroll, Marilyn E.; Smethells, John R.
The purpose of this review is to discuss recent findings related to sex differences in behavioral dyscontrol that lead to drug addiction, and clinical implications for humans are discussed. This review includes research conducted in animals and humans that reveals fundamental aspects of behavioral dyscontrol. The importance of sex differences in aspects of behavioral dyscontrol, such as impulsivity and compulsivity, are discussed as major determinants of drug addiction. Behavioral dyscontro...
Cherney, Isabelle D; Poss, Jordan L
To test the hunter-gatherer theory of cognitive sex differences, men and women each played four video games on a Wii console: two games simulating skills necessary for hunting (navigation and shooting) and two games simulating skills necessary for gathering (fine motor and visual search). Men outperformed women on the two hunting games, whereas there were no sex differences on the gathering skill games. The findings are discussed in terms of evolutionary psychology theory.
Macey, Paul M.; Rieken, Nicholas S.; Kumar, Rajesh; Ogren, Jennifer A.; Middlekauff, Holly R.; Wu, Paula; Woo, Mary A.; Harper, Ronald M.
Sex differences in autonomic regulation may underlie cardiovascular disease variations between females and males. One key autonomic brain region is the insular cortex, which typically consists of five main gyri in each hemisphere, and shows a topographical organization of autonomic function across those gyri. The present study aims to identify possible sex differences in organization of autonomic function in the insula. We studied brain functional magnetic resonance imaging (fMRI) responses t...
A lot of research has pointed out that television with its advertisements represents a part of the children's socialization, including the development of the sex roles. By designing different advertisements for boys and girls, today's advertisers additionally affect development and reinforcement of the children's traditional sex roles. The purpose of this study was to examine whether children are able to perceive differences in the content, style and structure of the message in di...
Gardener, Elyse K. T.; Carr, Andrea R.; MacGregor, Amy; Felmingham, Kim L.
Difficulties in emotion regulation have been implicated as a potential mechanism underlying anxiety and mood disorders. It is possible that sex differences in emotion regulation may contribute towards the heightened female prevalence for these disorders. Previous fMRI studies of sex differences in emotion regulation have shown mixed results, possibly due to difficulties in discriminating the component processes of early emotional reactivity and emotion regulation. The present study used event...
The aim of this research is to explore sex differences in undergraduates’ choices of potential employers. It focuses on a major employer (‘the Firm’), wishing to increase the number of job applications it receives from female undergraduates, and comprises three linked projects. No previous research was found that addresses sex differences in organisational choice. In the first project, a contribution is made by identifying, using Repertory Grids, eightyfour organisational at...
Ćosović Vojislav; Todorović Nevena; Andrić-Petrović Sanja; Marić Nadja P.
Introduction: Fluid intelligence is described as ability to rapidly solve novel problems and capacity to manage and easily adapt to new situations. Crystallized intelligence reflects ability to timely use lifetime-learned information and skills. Bearing in mind that intelligence is one of the impaired cognitive functions in psychosis, a question arises there are if any sex differences in patients, regarding total IQ, fluid or crystallized intelligence. Aim: To evaluate sex differences in psyc...
Niccolai, Linda M; King, Elizabeth J; Eritsyan, Ksenia U; Safiullina, Liliya; Rusakova, Maia M
We conducted a qualitative study of male sex work in St. Petersburg Russia with a focus on social vulnerabilities, HIV-risk perception and HIV-related behaviours. In-depth interviews were conducted with individuals knowledgeable about male sex work through their profession and with male sex workers themselves. Male sex work involves a variety of exchanges, including expensive vacations, negotiated monetary amounts or simply access to food. Methods of finding clients included the Internet, social venues (e.g. gay clubs and bars) and public places (e.g. parks). Use of the Internet greatly facilitated male sex work in a variety of ways. It was used by both individuals and agencies to find clients, and appeared to be increasing. Men often reported not being professionally connected to other male sex workers and limited disclosure about their work. Many were aware of the work-related risks to personal safety, including violence and robbery by clients. Perceived risk for HIV was mostly abstract and several exceptions to condom use with clients were noted. Alcohol use was reported as moderate but alcohol was consumed frequently in association with work. These data suggest that the most salient risks for male sex workers include professional isolation, threats to personal safety, limited perceived HIV risk and sub-optimal levels of condom use.
Arbeitman Michelle N
Full Text Available Abstract Background Understanding animal development and physiology at a molecular-biological level has been advanced by the ability to determine at high resolution the repertoire of mRNA molecules by whole transcriptome resequencing. This includes the ability to detect and quantify rare abundance transcripts and isoform-specific mRNA variants produced from a gene. The sex hierarchy consists of a pre-mRNA splicing cascade that directs the production of sex-specific transcription factors that specify nearly all sexual dimorphism. We have used deep RNA sequencing to gain insight into how the Drosophila sex hierarchy generates somatic sex differences, by examining gene and transcript isoform expression differences between the sexes in adult head tissues. Results Here we find 1,381 genes that differ in overall expression levels and 1,370 isoform-specific transcripts that differ between males and females. Additionally, we find 512 genes not regulated downstream of transformer that are significantly more highly expressed in males than females. These 512 genes are enriched on the × chromosome and reside adjacent to dosage compensation complex entry sites, which taken together suggests that their residence on the × chromosome might be sufficient to confer male-biased expression. There are no transcription unit structural features, from a set of features, that are robustly significantly different in the genes with significant sex differences in the ratio of isoform-specific transcripts, as compared to random isoform-specific transcripts, suggesting that there is no single molecular mechanism that generates isoform-specific transcript differences between the sexes, even though the sex hierarchy is known to include three pre-mRNA splicing factors. Conclusions We identify thousands of genes that show sex-specific differences in overall gene expression levels, and identify hundreds of additional genes that have differences in the abundance of isoform
Lachapelle, Josianne; Colegrave, Nick
The adaptive function of sex has been extensively studied, while less consideration has been given to the potential downstream consequences of sex on evolution. Here, we investigate one such potential consequence, the effect of sex on the repeatability of evolution. By affecting the repeatability of evolution, sex could have important implications for biodiversity, and for our ability to make predictions about the outcome of environmental change. We allowed asexual and sexual populations of Chlamydomonas reinhardtii to evolve in novel environments and monitored both their change in fitness and variance in fitness after evolution. Sex affected the repeatability of evolution by changing the importance of the effect of selection, chance, and ancestral constraints on the outcome of the evolutionary process. In particular, the effects of sex were highly dependent on the initial genetic composition of the population and on the environment. Given the lack of a consistent effect of sex on repeatability across the environments used here, further studies to dissect in more detail the underlying reasons for these differences as well as studies in additional environments are required if we are to have a general understanding of the effects of sex on the repeatability of evolution. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.
Klebsiella pneumoniae asparagine tDNAs are integration hotspots for different genomic islands encoding microcin E492 production determinants and other putative virulence factors present in hypervirulent strains
Andrés Esteban Marcoleta
Full Text Available Due to the developing of multi-resistant and invasive hypervirulent strains, Klebsiella pneumoniae has become one of the most urgent bacterial pathogen threats in the last years. Genomic comparison of a growing number of sequenced isolates has allowed the identification of putative virulence factors, proposed to be acquirable mainly through horizontal gene transfer. In particular, those related with synthesizing the antibacterial peptide microcin E492 (MccE492 and salmochelin siderophores were found to be highly prevalent among hypervirulent strains. The determinants for the production of both molecules were first reported as part of a 13-kbp segment of K. pneumoniae RYC492 chromosome, and were cloned and characterized in E. coli. However, the genomic context of this segment in K. pneumoniae remained uncharacterized.In this work we provided experimental and bioinformatics evidence indicating that the MccE492 cluster is part of a highly conserved 23-kbp genomic island (GI named GIE492, that was integrated in a specific asparagine-tRNA gene (asn-tDNA and was found in a high proportion of isolates from liver abscesses sampled around the world. This element resulted to be unstable and its excision frequency increased after treating bacteria with mytomicin C and upon the overexpression of the island-encoded integrase. Besides the MccE492 genetic cluster, it invariably included an integrase-coding gene, at least 7 protein-coding genes of unknown function, and a putative transfer origin that possibly allows this GI to be mobilized through conjugation. In addition, we analyzed the asn-tDNA loci of all the available K. pneumoniae assembled chromosomes to evaluate them as GI-integration sites. Remarkably, 73% of the strains harbored at least one GI integrated in one of the four asn-tDNA present in this species, confirming them as integration hotspots. Each of these tDNAs was occupied with different frequencies, although they were 100% identical. Also, we
Becker Jill B
Full Text Available Abstract In this review we propose that there are sex differences in how men and women enter onto the path that can lead to addiction. Males are more likely than females to engage in risky behaviors that include experimenting with drugs of abuse, and in susceptible individuals, they are drawn into the spiral that can eventually lead to addiction. Women and girls are more likely to begin taking drugs as self-medication to reduce stress or alleviate depression. For this reason women enter into the downward spiral further along the path to addiction, and so transition to addiction more rapidly. We propose that this sex difference is due, at least in part, to sex differences in the organization of the neural systems responsible for motivation and addiction. Additionally, we suggest that sex differences in these systems and their functioning are accentuated with addiction. In the current review we discuss historical, cultural, social and biological bases for sex differences in addiction with an emphasis on sex differences in the neurotransmitter systems that are implicated.
Deaner, Robert O; Addona, Vittorio; Mead, Michael P
It is well established that men are more likely than women to engage in direct competition, but it is unclear if this reflects social structural conditions or evolved predispositions. These hypotheses can be addressed by quantifying competitiveness in sports and testing if the sex difference is decreasing over time in the U.S., a society where social roles have converged. Study 1 assessed participation and the occurrence of relatively fast performances by masters runners (40-74 years old) at recent road races and track meets. Fast performances occurred over 20 times more often at track meets than at road races. Women comprised 55% of finishers at roads races but only 15-28% of finishers at track meets. Thus, the sex difference in masters track participation can serve as a measure of the sex difference in competitiveness. Study 2 used data from national championship meets and yearly rankings lists to test whether the sex difference in masters track participation decreased from 1988-2012. The sex difference decreased overall, but there was no evidence of change since the late 1990s. Therefore, the sex difference in the willingness to engage in direct sports competition appears to reflect both social structural conditions and evolved predispositions.
Full Text Available OBJECTIVES: Variations in the prevalence of sex-hormone-related diseases have been observed between Asian ethnic groups living in the same country; however, available data concerning their sex hormone levels are limited. The present study aimed to determine the influence of ethnicity and age on the sex hormone levels of Malay and Chinese men in Malaysia. METHODS: A total of 547 males of Malay and Chinese ethnicity residing in the Klang Valley Malaysia underwent a detailed screening, and their blood was collected for sex hormones analyses. RESULTS: Testosterone levels were normally distributed in the men (total, free and non-sex hormone-binding globulin (SHBG bound fractions, and significant ethnic differences were observed (p<0.05; however, the effect size was small. In general, testosterone levels in males began to decline significantly after age 50. Significant ethnic differences in total, free and non-SHBG bound fraction estradiol levels were observed in the 20-29 and 50-59 age groups (p<0.05. The estradiol levels of Malay men decreased as they aged, but they increased for Chinese men starting at age 40. CONCLUSIONS: Small but significant differences in testosterone levels existed between Malay and Chinese males. Significant age and race differences existed in estradiol levels. These differences might contribute to the ethnic group differences in diseases related to sex hormones, which other studies have found in Malaysia.
Full Text Available OBJECTIVES: Variations in the prevalence of sex-hormone-related diseases have been observed between Asian ethnic groups living in the same country; however, available data concerning their sex hormone levels are limited. The present study aimed to determine the influence of ethnicity and age on the sex hormone levels of Malay and Chinese men in Malaysia. METHODS: A total of 547 males of Malay and Chinese ethnicity residing in the Klang Valley Malaysia underwent a detailed screening, and their blood was collected for sex hormones analyses. RESULTS: Testosterone levels were normally distributed in the men (total, free and non-sex hormone-binding globulin (SHBG bound fractions, and significant ethnic differences were observed (p<0.05; however, the effect size was small. In general, testosterone levels in males began to decline significantly after age 50. Significant ethnic differences in total, free and non-SHBG bound fraction estradiol levels were observed in the 20-29 and 50-59 age groups (p<0.05. The estradiol levels of Malay men decreased as they aged, but they increased for Chinese men starting at age 40. CONCLUSIONS: Small but significant differences in testosterone levels existed between Malay and Chinese males. Significant age and race differences existed in estradiol levels. These differences might contribute to the ethnic group differences in diseases related to sex hormones, which other studies have found in Malaysia.
Hulthén, K.; Chapman, B.B.; Nilsson, P.A.
the probability of survival within the size range tagged (119–280 m ), nor were there differences in timing of migration the following season between individuals sexed and tagged in spring and individuals tagged in autumn (i.e. outside the reproductive period). Also, a similar per cent of R. rutilus sexed...... and tagged in spring and tagged in autumn migrated the following season (34·5 and 34·7%). Moreover, long-term recapture data revealed no significant differences in body condition between R. rutilus individuals sexed and tagged in spring, individuals tagged in autumn and unmanipulated individuals....... The observed sex ratio of recaptured fish did not differ from the expected values of equal recapture rates between males and females. Hence, there is no observable evidence for an adverse effect of tagging close to the reproductive period and therefore this method is suitable for studying intersexual...
Kolotkin, Richard A.; And Others
This experiment investigated: (1) relationships among locus of control, attributional style, and depression; (2) if a depressogenic attributional style could be empirically isolated; and (3) if reliable relationships existed between attribution and depression when depression was operationalized using different instruments. Subjects completed the…