Sex differences in learning processes of classical and operant conditioning

PubMed Central

Dalla, Christina; Shors, Tracey J.

2009-01-01

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 on 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. PMID:19272397

Sex differences in learning processes of classical and operant conditioning.

PubMed

Dalla, Christina; Shors, Tracey J

2009-05-25

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.

Biological Sex Differences in Depression: A Systematic Review.

PubMed

Labaka, Ainitze; Goñi-Balentziaga, Olatz; Lebeña, Andrea; Pérez-Tejada, Joana

2018-07-01

Depression is the leading cause of disability worldwide, and its prevalence is 2 times higher in women than in men. There is, however, a lack of data on sex-specific pathophysiology of this disorder. The purpose of this systematic review is to identify the biological sex differences found in major depressive disorder (MDD) in studies published in the last 10 years. We conducted a literature search using the Medline, PsycInfo, PubMed, and Web of Science databases, selecting English-language studies that included physiological measures compared by sex in addition to MDD. We identified 20 relevant studies, which consisted primarily of mixed methodology and samples. The reported physiological measures comprised a variety of serum biomarkers, gene mRNA expression, and brain activity. Findings suggest different biological patterns in those with MDD depending on sex. Specifically, women presented higher levels of inflammatory, neurotrophic, and serotonergic markers and a stronger correlation between levels of some inflammatory and neurotrophic factors and the severity of symptoms. This review provides information about possible different biological patterns for women and men with depressive disorder and may have important implications for treatment. Future research should include homogeneous samples; make comparisons based on sex, control sex hormone fluctuations and pharmacological treatment; and use consistent criteria for evaluating psychobiological changes in MDD.

Sex Differences, Sex-Role Orientation, and Reward Allocations.

ERIC Educational Resources Information Center

Olejnik, Anthony B.

1982-01-01

In separate studies, examined (1) ways that college students allocated rewards to children performing in team and competitive situations, and (2) the relationship between sex role orientation and reward allocations. Found that sex and situational differences in reward allocations are affected by sex role orientation and differential socialization…

Sex Differences in Common Sports Injuries.

PubMed

Lin, Cindy; Casey, Ellen; Herman, Daniel; Katz, Nicole; Tenforde, Adam

2018-03-14

Common sports injuries include bone stress injuries (BSIs), anterior cruciate ligament (ACL) injuries, and concussions. Less commonly recognized are the specific sex differences in epidemiology, risk factors, and outcomes of these conditions by sex. An understanding of these factors can improve their clinical management, from prescribing appropriate prehabilitation to guiding postinjury rehabilitation and return to play. This narrative review summarizes the sex differences in the diagnosis and management of BSIs, ACL injuries, and concussions. Although BSIs are more common in female athletes, risk factors for both sexes include prior injury and relative energy deficiency in sport (RED-S). Risk factors in female athletes include smaller calf girth, femoral adduction, and higher rates of loading. Female athletes are also at greater risk for developing ACL injuries in high school and college, but their injury rate is similar in professional sports. Increased lateral tibial slope, smaller ACL size, and suboptimal landing mechanics are additional risk factors more often present in female athletes. Male athletes are more likely to have ACL surgery and have a higher rate of return to sport. Concussions occur more commonly in female athletes; however, female athletes are also more likely to report concussions. Male athletes more commonly sustain concussion through contact with another player. Female athletes more commonly sustain injury from contact with playing equipment. Managing post-concussion symptoms is important, and female athletes may have prolonged symptoms. An understanding of the sex-specific differences in these common sports injuries can help optimize their prehabilitation and rehabilitation. Copyright © 2018 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

Sex Hormones and Sex Chromosomes Cause Sex Differences in the Development of Cardiovascular Diseases.

PubMed

Arnold, Arthur P; Cassis, Lisa A; Eghbali, Mansoureh; Reue, Karen; Sandberg, Kathryn

2017-05-01

This review summarizes recent evidence concerning hormonal and sex chromosome effects in obesity, atherosclerosis, aneurysms, ischemia/reperfusion injury, and hypertension. Cardiovascular diseases occur and progress differently in the 2 sexes, because biological factors differing between the sexes have sex-specific protective and harmful effects. By comparing the 2 sexes directly, and breaking down sex into its component parts, one can discover sex-biasing protective mechanisms that might be targeted in the clinic. Gonadal hormones, especially estrogens and androgens, have long been found to account for some sex differences in cardiovascular diseases, and molecular mechanisms mediating these effects have recently been elucidated. More recently, the inherent sexual inequalities in effects of sex chromosome genes have also been implicated as contributors in animal models of cardiovascular diseases, especially a deleterious effect of the second X chromosome found in females but not in males. Hormonal and sex chromosome mechanisms interact in the sex-specific control of certain diseases, sometimes by opposing the action of the other. © 2017 American Heart Association, Inc.

[Sex differences and anesthesiology: preface and comments].

PubMed

Nishno, Takashi

2009-01-01

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.

Sex and gender differences in therapy of type 2 diabetes.

PubMed

Kautzky-Willer, Alexandra; Harreiter, Jürgen

2017-09-01

Clinical guidelines for the management of type 2 diabetes recommend individual therapy considering age, duration of disease, presence of complication and risk of hypoglycaemia. However, at present, the patient's sex has no impact on clinical decisions. Yet, there is mounting data pointing at biological and psychosocial differences between men and women with great impact on progression of disease and complications. Moreover, choices and preferences of therapeutic strategies as well as adherence to lifestyle and pharmacological interventions differ in both sexes. In addition, drug therapy may have sex-specific side effects. Therefore, there is need of more research on biological differences and of evidence-based individualised targeted sex-sensitive therapeutic concepts. Clinical guidelines must consider relevant sex-differences. Development and implementation of sex-specific programs may help to improve adherence to therapy and to reduce progression of disease and development of complications. A more gender-sensitive clinical approach may improve quality of life and increase health and life expectancy in men and women with type 2 diabetes. Copyright © 2017 Elsevier B.V. All rights reserved.

The Stability of Same-Sex Cohabitation, Different-Sex Cohabitation, and Marriage

ERIC Educational Resources Information Center

Lau, Charles Q.

2012-01-01

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…

Explaining the sex difference in dyslexia.

PubMed

Arnett, Anne B; Pennington, Bruce F; Peterson, Robin L; Willcutt, Erik G; DeFries, John C; Olson, Richard K

2017-06-01

Males are diagnosed with dyslexia more frequently than females, even in epidemiological samples. This may be explained by greater variance in males' reading performance. We expand on previous research by rigorously testing the variance difference theory, and testing for mediation of the sex difference by cognitive correlates. We developed an analytic framework that can be applied to group differences in any psychiatric disorder. Males' overrepresentation in the low performance tail of the reading distribution was accounted for by mean and variance differences across sex. There was no sex difference at the high performance tail. Processing speed (PS) and inhibitory control partially mediated the sex difference. Verbal reasoning emerged as a strength in males. Our results complement a previous finding that PS partially mediates the sex difference in symptoms of attention deficit/hyperactivity disorder (ADHD), and helps explain the sex difference in both dyslexia and ADHD and their comorbidity. © 2017 Association for Child and Adolescent Mental Health.

Sex differences in the Simon task help to interpret sex differences in selective attention.

PubMed

Stoet, Gijsbert

2017-05-01

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.

Sex differences in primary hypertension

PubMed Central

2012-01-01

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

Sex differences in the neurobiology of drug addiction.

PubMed

Bobzean, Samara A M; DeNobrega, Aliza K; Perrotti, Linda I

2014-09-01

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.

Mental rotation does not account for sex differences in left-right confusion.

PubMed

Ocklenburg, Sebastian; Hirnstein, Marco; Ohmann, Hanno Andreas; Hausmann, Markus

2011-06-01

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 involve mental rotation. That is, sex differences that are reported for some LRC tasks are strongly affected by the well-documented male advantage in mental rotation. To test this assumption, 91 participants were investigated on two LRC tasks: The Left-Right Commands Task and the Bergen Left-Right Discrimination Test. Additionally, participants were asked to complete an LRC self-rating questionnaire. To rule out the possibility that sex differences in LRC are confounded by sex differences in mental rotation, male and female participants were matched for mental rotation performance, resulting in a sample of 46 matched participants. These matched participants showed robust sex differences in favour of men in all LRC measurements. This suggests that pronounced sex differences in LRC are a genuine phenomenon that exists independently of sex differences in mental rotation. Copyright © 2011 Elsevier Inc. All rights reserved.

Sex differences in stress-related receptors: ″micro″ differences with ″macro″ implications for mood and anxiety disorders

PubMed Central

2013-01-01

Stress-related psychiatric disorders, such as unipolar depression and post-traumatic stress disorder (PTSD), occur more frequently in women than in men. Emerging research suggests that sex differences in receptors for the stress hormones, corticotropin releasing factor (CRF) and glucocorticoids, contribute to this disparity. For example, sex differences in CRF receptor binding in the amygdala of rats may predispose females to greater anxiety following stressful events. Additionally, sex differences in CRF receptor signaling and trafficking in the locus coeruleus arousal center combine to make females more sensitive to low levels of CRF, and less adaptable to high levels. These receptor differences in females could lead to hyperarousal, a dysregulated state associated with symptoms of depression and PTSD. Similar to the sex differences observed in CRF receptors, sex differences in glucocorticoid receptor (GR) function also appear to make females more susceptible to dysregulation after a stressful event. Following hypothalamic pituitary adrenal axis activation, GRs are critical to the negative feedback process that inhibits additional glucocorticoid release. Compared to males, female rats have fewer GRs and impaired GR translocation following chronic adolescent stress, effects linked to slower glucocorticoid negative feedback. Thus, under conditions of chronic stress, attenuated negative feedback in females would result in hypercortisolemia, an endocrine state thought to cause depression. Together, these studies suggest that sex differences in stress-related receptors shift females more easily into a dysregulated state of stress reactivity, linked to the development of mood and anxiety disorders. The implications of these receptor sex differences for the development of novel pharmacotherapies are also discussed. PMID:23336736

Sex differences in the human brain and the impact of sex chromosomes and sex hormones.

PubMed

Lentini, E; Kasahara, M; Arver, S; Savic, I

2013-10-01

While there has been increasing support for the existence of cerebral sex differences, the mechanisms underlying these differences are unclear. Based on animal data, it has long been believed that sexual differentiation of the brain is primarily linked to organizational effects of fetal testosterone. This view is, however, in question as more recent data show the presence of sex differences before the onset of testosterone production. The present study focuses on the impact that sex chromosomes might have on these differences. Utilizing the inherent differences in sex and X-chromosome dosage among XXY males, XY males, and XX females, comparative voxel-based morphometry was conducted using sex hormones and sex chromosomes as covariates. Sex differences in the cerebellar and precentral gray matter volumes (GMV) were found to be related to X-chromosome dosage, whereas sex differences in the amygdala, the parahippocamus, and the occipital cortex were linked to testosterone levels. An increased number of sex chromosomes was associated with reduced GMV in the amygdala, caudate, and the temporal and insular cortices, with increased parietal GMV and reduced frontotemporal white matter volume. No selective, testosterone independent, effect of the Y-chromosome was detected. Based on these observations, it was hypothesized that programming of the motor cortex and parts of cerebellum is mediated by processes linked to X-escapee genes, which do not have Y-chromosome homologs, and that programming of certain limbic structures involves testosterone and X-chromosome escapee genes with Y-homologs.

Birth cohort and the specialization gap between same-sex and different-sex couples.

PubMed

Giddings, Lisa; Nunley, John M; Schneebaum, Alyssa; Zietz, Joachim

2014-04-01

We examine differences in household specialization between same-sex and different-sex couples within and across three birth cohorts: Baby Boomers, Generation X, and Generation Y. Using three measures of household specialization, we find that same-sex couples are less likely than their different-sex counterparts to exhibit a high degree of specialization. However, the "specialization gap" between same-sex and different-sex couples narrows across birth cohorts. These findings are indicative of a cohort effect. Our results are largely robust to the inclusion of a control for the presence of children and for subsets of couples with and without children. We provide three potential explanations for why the specialization gap narrows across cohorts. First, different-sex couples from more recent birth cohorts may have become more like same-sex couples in terms of household specialization. Second, social and legal changes may have prompted a greater degree of specialization within same-sex couples relative to different-sex couples. Last, the advent of reproductive technologies, which made having children easier for same-sex couples from more recent birth cohorts, could result in more specialization in such couples relative to different-sex couples.

Issues related to sex differences in antipsychotic treatment.

PubMed

Crawford, Mitchell B; DeLisi, Lynn E

2016-05-01

The effectiveness, side-effect profiles, and numerous other characteristics of antipsychotic medications have been extensively studied. However, the majority of publications do not address the many potential sex differences in efficacy and doses of medications, as well as other sex-specific considerations. Of studies that exist, some suggest that female patients respond to lower doses of antipsychotic medications than males and that side-effect profiles vary between the sexes. However, the majority of preclinical trials use only male laboratory animals, and human clinical trials consist of too few women to analyze their response as a separate group. Although changes in hormone production occurring at multiple stages throughout a women's life (such as during pregnancy, breast feeding, menopause, and postmenopausal) are presented as too complex to deal with in clinical trials, they could instead be embraced as clinical dilemmas that require additional study and consideration. We suggest that a focus should be made to reanalyze data from existing major treatment trials of antipsychotics to determine what medications specifically provide the most efficacy for female patients and at what dose range. In addition, new prospective studies are needed to specifically address appropriate adjustments in psychopharmacologic treatment for female patients during pregnancy, and when postmenopausal. More studies of the effects of antipsychotics on male and female fetuses in utero and during breast feeding are also needed to better manage women with schizophrenia and their offspring on a long-term basis in the community. There is currently too little known about sex differences in neuropharmacology. With the new USA National Institutes of Health policy to include sex in all new proposals, the time has come to close this gap in knowledge.

Potential Sex Differences Relative to Autism Spectrum Disorder and Metals.

PubMed

Dickerson, Aisha S; Rotem, Ran S; Christian, MacKinsey A; Nguyen, Vy T; Specht, Aaron J

2017-12-01

This study aims to summarize the current body of literature on the relationship between various toxic metals exposures (i.e., aluminum, antimony, arsenic, beryllium, cadmium, chromium, lead, manganese, and nickel) and autism spectrum disorder (ASD), with a focus on potential sex differences in these associations. Sex differences in ASD diagnosis and mutagenic effects of toxic exposures indicate that sex differences may play a major part in the causal relationship of any potential associations seen; however, we were only able to find three studies that reported on sex differences in observed associations with toxic metals exposure and ASD. We also found several studies investigating associations between ASD and metals exposures, including 11 on aluminum, 6 on antimony, 15 on arsenic, 5 on beryllium, 17 on cadmium, 11 on chromium, 25 on lead, 14 on manganese, and 13 on nickel with markers of exposure in hair, urine, blood, teeth, fingernails, and air pollution. Results for each metal were conflicting, but studies on cadmium and lead yielded the highest proportion of studies with positive results (72% and 36%, respectively). Based on our examination of existing literature, the current evidence warrants a considerable need for evaluations of sex differences in future studies assessing the association between metals exposures and ASD. Additionally, failure to account for potential sex differences could result in bias and misinterpretation of exposure-disease relationships.

Sex Differences in Social Behavior.

ERIC Educational Resources Information Center

Baker, Therese

Examining theories from a wide spectrum of disciplines, this paper categorizes research on sex differences in social behavior into four groups and examines the implications of each. The first category of research interprets sex differences as the result of anatomical differences which later affect psychological roles. The implication of this…

Sex Differences in Stroke Therapies

PubMed Central

Sohrabji, Farida; Park, Min Jung; Mahnke, Amanda H

2016-01-01

Stroke is the 5th leading cause of death and acquired disability in aged populations. Women are disproportionally affected by stroke, having a higher incidence and worse outcomes than men. Numerous preclinical studies have discovered novel therapies for the treatment of stroke, but almost all of these were found to be unsuccessful in clinical trials. Despite known sex differences in occurrence and severity of stroke, few therapeutics, both preclinically and clinically, take into account possible sex differences in treatment. Reanalysis of data from the only currently FDA-approved stroke therapy, tPA, has shown to not only improve stroke outcomes for both sexes, but to also show sexual dimorphism by more robust improvement in stroke outcome in females. Experimental evidence supports the inclusion of sex as a variable in the study of a number of novel stroke drugs and therapies, including preclinical studies of anti-inflammatory drugs (minocycline), stimulators of cell survival (IGF-1), and inhibitors of cell death pathways (pharmacological inhibition of PARP-1, NO production, and caspase activation), as well as in current clinical trials of stem cell therapy and cortical stimulation. Overall, study design and analyses in clinical trials, as well as in preclinical studies, must include both sexes equally, consider possible sex differences in the analyses, and report the differences/similarities in more systemized/structured way to translate promising therapies to both sexes and increase stroke recovery. PMID:27870437

Sex Differences in Human and Animal Toxicology.

PubMed

Gochfeld, Michael

2017-01-01

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.

Sex differences in stroke therapies.

PubMed

Sohrabji, Farida; Park, Min Jung; Mahnke, Amanda H

2017-01-02

Stroke is the fifth leading cause of death and acquired disability in aged populations. Women are disproportionally affected by stroke, having a higher incidence and worse outcomes than men. Numerous preclinical studies have discovered novel therapies for the treatment of stroke, but almost all of these have been shown to be unsuccessful in clinical trials. Despite known sex differences in occurrence and severity of stroke, few preclinical or clinical therapeutics take into account possible sex differences in treatment. Reanalysis of data from studies of tissue plasminogen activator (tPA), the only currently FDA-approved stroke therapy, has shown that tPA improves stroke outcomes for both sexes and also shows sexual dimorphism by more robust improvement in stroke outcome in females. Experimental evidence supports the inclusion of sex as a variable in the study of a number of novel stroke drugs and therapies, including preclinical studies of anti-inflammatory drugs (minocycline), stimulators of cell survival (insulin-like growth factor-1), and inhibitors of cell death pathways (pharmacological inhibition of poly[ADP-ribose] polymerase-1, nitric oxide production, and caspase activation) as well as in current clinical trials of stem cell therapy and cortical stimulation. Overall, study design and analysis in clinical trials as well as in preclinical studies must include both sexes equally, consider possible sex differences in the analyses, and report the differences/similarities in more systematic/structured ways to allow promising therapies for both sexes and increase stroke recovery. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

No sex differences in the TAMI.

PubMed

Madan, Christopher R; Singhal, Anthony

2015-05-01

The Test of Ability in Movement Imagery (TAMI; Madan and Singhal in J Mot Behav 45:153-166, 2013) has recently been developed as an objective measure for evaluating individual ability in movement imagery. Other tests of imagery have reported sex differences, including the mental rotations test (MRT) and the Vividness of Movement Imagery Questionnaire (VMIQ). However, some have attributed these observed sex differences to other processes, such as difference in spatial abilities and confidence. Here, we tested for sex differences in the TAMI in a large sample of young adults (N = 246). In the same sample, we also administered a modified version of the MRT that included both block configurations and human figures and the VMIQ2. This modified MRT was used, as the imagery processes involved in the TAMI may be more similar to those involved in the rotations of human figures. While strong sex differences were found in both subscales of the modified MRT, no sex differences were observed in the TAMI.

Sex differences in T cells in hypertension.

PubMed

Tipton, Ashlee J; Sullivan, Jennifer C

2014-12-01

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

A Population-Based Study of Alcohol Use in Same-Sex and Different-Sex Unions

PubMed Central

Reczek, Corinne; Liu, Hui; Spiker, Russell

2014-01-01

The present study advances research on union status and health by providing a first look at alcohol use differentials among different-sex and same-sex married and cohabiting individuals using nationally representative population-based data (National Health Interview Surveys 1997–2011, N = 181,581). The results showed that both same-sex and different-sex married groups reported lower alcohol use than both same-sex and different-sex cohabiting groups. The results further revealed that same-sex and different-sex married individuals reported similar levels of alcohol use, whereas same-sex and different-sex cohabiting individuals reported similar levels of alcohol use. Drawing on marital advantage and minority stress approaches, the findings suggest that it is cohabitation status—not same-sex status—that is associated with elevated alcohol rates. PMID:24860195

How to study sex differences in addiction using animal models

PubMed Central

Carroll, Marilyn E.; Lynch, Wendy J.

2016-01-01

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 vs. adult). Novel treatments for addiction are also discussed, such as competing nondrug 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. PMID:27345022

Sex Differences in Response to Visual Sexual Stimuli: A Review

PubMed Central

Rupp, Heather A.; Wallen, Kim

2009-01-01

This article reviews what is currently known about how men and women respond to the presentation of visual sexual stimuli. While the assumption that men respond more to visual sexual stimuli is generally empirically supported, previous reports of sex differences are confounded by the variable content of the stimuli presented and measurement techniques. We propose that the cognitive processing stage of responding to sexual stimuli is the first stage in which sex differences occur. The divergence between men and women is proposed to occur at this time, reflected in differences in neural activation, and contribute to previously reported sex differences in downstream peripheral physiological responses and subjective reports of sexual arousal. Additionally, this review discusses factors that may contribute to the variability in sex differences observed in response to visual sexual stimuli. Factors include participant variables, such as hormonal state and socialized sexual attitudes, as well as variables specific to the content presented in the stimuli. Based on the literature reviewed, we conclude that content characteristics may differentially produce higher levels of sexual arousal in men and women. Specifically, men appear more influenced by the sex of the actors depicted in the stimuli while women’s response may differ with the context presented. Sexual motivation, perceived gender role expectations, and sexual attitudes are possible influences. These differences are of practical importance to future research on sexual arousal that aims to use experimental stimuli comparably appealing to men and women and also for general understanding of cognitive sex differences. PMID:17668311

Sex Differences in Examination Performance: Do These Reflect Differences in Ability or Sex-Role Stereotypes?

ERIC Educational Resources Information Center

Murphy, Roger J. L.

1978-01-01

Sex differences in GCE 'O' level examination performance are reflected both in the number of boys and girls entering for different subjects and in the numbers obtaining the higher grades. From a review of possible factors, it seems that sex-role stereotyping is the most influential. (Author/SJL)

Sex differences in cough reflex.

PubMed

Plevkova, J; Buday, T; Kavalcikova-Bogdanova, N; Ioan, I; Demoulin-Alexikova, S

2017-11-01

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.

National differences in gender–science stereotypes predict national sex differences in science and math achievement

PubMed Central

Nosek, Brian A.; Smyth, Frederick L.; Sriram, N.; Lindner, Nicole M.; Devos, Thierry; Ayala, Alfonso; Bar-Anan, Yoav; Bergh, Robin; Cai, Huajian; Gonsalkorale, Karen; Kesebir, Selin; Maliszewski, Norbert; Neto, Félix; Olli, Eero; Park, Jaihyun; Schnabel, Konrad; Shiomura, Kimihiro; Tulbure, Bogdan Tudor; Wiers, Reinout W.; Somogyi, Mónika; Akrami, Nazar; Ekehammar, Bo; Vianello, Michelangelo; Banaji, Mahzarin R.; Greenwald, Anthony G.

2009-01-01

About 70% of more than half a million Implicit Association Tests completed by citizens of 34 countries revealed expected implicit stereotypes associating science with males more than with females. We discovered that nation-level implicit stereotypes predicted nation-level sex differences in 8th-grade science and mathematics achievement. Self-reported stereotypes did not provide additional predictive validity of the achievement gap. We suggest that implicit stereotypes and sex differences in science participation and performance are mutually reinforcing, contributing to the persistent gender gap in science engagement. PMID:19549876

Sex Differences in Examination Performance: Do These Reflect Differences in Ability or Sex-Role Stereotypes?

ERIC Educational Resources Information Center

Murphy, Roger J. L.

Many academic examinations exhibit sex differences in terms of entry figures and pass rates. This fact is illustrated by a selection of statistics from the British GCE "O" level examination results for June 1976. These results are discussed in terms of three possible causes: innate differences in intellectual functioning, sex role…

Sex Differences in Dichotic Listening

ERIC Educational Resources Information Center

Voyer, Daniel

2011-01-01

The present study quantified the magnitude of sex differences in perceptual asymmetries as measured with dichotic listening. This was achieved by means of a meta-analysis of the literature dating back from the initial use of dichotic listening as a measure of laterality. The meta-analysis included 249 effect sizes pertaining to sex differences and…

Sex Differences in Fetal Habituation

ERIC Educational Resources Information Center

Hepper, Peter G.; Dornan, James C.; Lynch, Catherine

2012-01-01

There is some evidence for sex differences in habituation in the human fetus, but it is unknown whether this is due to differences in central processing (habituation) or in more peripheral processes, sensory or motor, involved in the response. This study examined whether the sex of the fetus influenced auditory habituation at 33 weeks of…

Sex differences in social cognition: The case of face processing.

PubMed

Proverbio, Alice Mado

2017-01-02

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.

Sex Differences in Muscle Wasting.

PubMed

Anderson, Lindsey J; Liu, Haiming; Garcia, Jose M

2017-01-01

With aging and other muscle wasting diseases, men and women undergo similar pathological changes in skeletal muscle: increased inflammation, enhanced oxidative stress, mitochondrial dysfunction, satellite cell senescence, elevated apoptosis and proteasome activity, and suppressed protein synthesis and myocyte regeneration. Decreased food intake and physical activity also indirectly contribute to muscle wasting. Sex hormones also play important roles in maintaining skeletal muscle homeostasis. Testosterone is a potent anabolic factor promoting muscle protein synthesis and muscular regeneration. Estrogens have a protective effect on skeletal muscle by attenuating inflammation; however, the mechanisms of estrogen action in skeletal muscle are less well characterized than those of testosterone. Age- and/or disease-induced alterations in sex hormones are major contributors to muscle wasting. Hence, men and women may respond differently to catabolic conditions because of their hormonal profiles. Here we review the similarities and differences between men and women with common wasting conditions including sarcopenia and cachexia due to cancer, end-stage renal disease/chronic kidney disease, liver disease, chronic heart failure, and chronic obstructive pulmonary disease based on the literature in clinical studies. In addition, the responses in men and women to the commonly used therapeutic agents and their efficacy to improve muscle mass and function are also reviewed.

Sex Differences in Mental and Behavioral Traits.

ERIC Educational Resources Information Center

Garai, Josef E.; Scheinfeld, Amram

1968-01-01

This review of research conducted on sex differences attempts to answer the following questions: (1) Do the sexes differ in their basic capacities for specific types of mental performance and occupational achievement? (2) If such differences exist, to what extent are they genetically determined? (3) Are sex differences in abilities, interests, and…

Sex similarities and differences in risk factors for recurrence of major depression.

PubMed

van Loo, Hanna M; Aggen, Steven H; Gardner, Charles O; Kendler, Kenneth S

2017-11-27

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.

Students’ Spatial Performance: Cognitive Style and Sex Differences

NASA Astrophysics Data System (ADS)

Hanifah, U.; Juniati, D.; Siswono, T. Y. E.

2018-01-01

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.

Sex differences in same-sex direct aggression and sociosexuality: the role of risky impulsivity.

PubMed

Cross, Catharine P

2010-12-23

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.

A heads up on concussions: are there sex-related differences?

PubMed

Brook, Emily M; Luo, Xuan; Curry, Emily J; Matzkin, Elizabeth G

2016-01-01

Head injuries are a major concern for physicians in athletes of all ages. Specifically, sports-related concussions are becoming an all-too-common injury among female athletes. The incidence of concussions among female athletes has likely increased over the past few decades because of an increase in sports participation afforded by Title IX. It would be useful for physicians to have general knowledge of concussions and their potential sex-related differences. This review article summarizes the current body of research concerning sex-related differences in concussion epidemiology and outcomes. A literature search was performed using PubMed and included all articles published from 1993 to present, with a predominant focus on research conducted over the past fifteen years. Additional articles were found using the bibliography from articles found through the PubMed search. Several articles have compared incidence, severity of neurological deficit, constellation of symptoms, and length of recovery post-concussion in males and females. However, the literature does not unanimously support a significant sex-related difference in concussions. Lack of consensus in the literature can be attributed to differences between patient populations, different tools used to study concussions, including subjective or objective measures, and differences in mechanisms of injury. We conclude that concussions are a serious injury in both male and female athletes, and physicians should have a very high index of suspicion regardless of sex, because there currently is not sufficient consensus in the literature to institute sex-related changes to concussion management. Current research may suggest a sex-related difference pertaining to sports-related concussions, but further evaluation is needed on this topic.

Sex differences in the neural mechanisms mediating addiction: a new synthesis and hypothesis

PubMed Central

2012-01-01

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. PMID:22676718

Elevated Amygdala Perfusion Mediates Developmental Sex Differences in Trait Anxiety

PubMed Central

Kaczkurkin, Antonia N.; Moore, Tyler M.; Ruparel, Kosha; Ciric, Rastko; Calkins, Monica E.; Shinohara, Russell T.; Elliott, Mark A.; Hopson, Ryan; Roalf, David R.; Vandekar, Simon N.; Gennatas, Efstathios D.; Wolf, Daniel H.; Scott, J. Cobb; Pine, Daniel S.; Leibenluft, Ellen; Detre, John A.; Foa, Edna B.; Gur, Raquel E.; Gur, Ruben C.; Satterthwaite, Theodore D.

2016-01-01

Background Adolescence is a critical period for emotional maturation and is a time when clinically significant symptoms of anxiety and depression increase, particularly in females. However, few studies relate developmental differences in symptoms of anxiety and depression to brain development. Cerebral blood flow (CBF) is one brain phenotype that is known to have marked developmental sex differences. Methods We investigated whether developmental sex differences in CBF mediated sex differences in anxiety and depression symptoms by capitalizing upon a large sample of 875 youths who completed cross-sectional imaging as part of the Philadelphia Neurodevelopmental Cohort. Perfusion was quantified on a voxelwise basis using arterial spin labeled MRI at 3T. Perfusion images were related to trait and state anxiety using a general additive model with penalized splines, while controlling for gray matter density on a voxelwise basis. Clusters found to be related to anxiety were evaluated for interactions with age, sex, and puberty. Results Trait anxiety was associated with elevated perfusion in a network of regions including the amygdala, anterior insula, and fusiform cortex, even after accounting for pre-scanner state anxiety. Notably, these relationships strengthened with age and the transition through puberty. Moreover, higher trait anxiety in post-pubertal females was mediated by elevated perfusion of the left amygdala. Conclusions Taken together, these results demonstrate that differences in the evolution of cerebral perfusion during the adolescent period may be a critical element of the affective neurobiology underlying sex differences in anxiety and mood symptoms. PMID:27395327

Cigarette Smoking in Same-Sex and Different-Sex Unions: The Role of Socioeconomic and Psychological Factors

PubMed Central

Liu, Hui; Brown, Dustin

2014-01-01

Cigarette smoking has long been a target of public health intervention because it substantially contributes to morbidity and mortality. Individuals in different-sex marriages have lower smoking risk (i.e., prevalence and frequency) than different-sex cohabiters. However, little is known about the smoking risk of individuals in same-sex cohabiting unions. We compare the smoking risk of individuals in different-sex marriages, same-sex cohabiting unions, and different-sex cohabiting unions using pooled cross-sectional data from the 1997–2010 National Health Interview Surveys (N = 168,514). We further examine the role of socioeconomic status (SES) and psychological distress in the relationship between union status and smoking. Estimates from multinomial logistic regression models reveal that same-sex and different-sex cohabiters experience similar smoking risk when compared to one another, and higher smoking risk when compared to the different-sex married. Results suggest that SES and psychological distress factors cannot fully explain smoking differences between the different-sex married and same-sex and different-sex cohabiting groups. Moreover, without same-sex cohabiter’s education advantage, same-sex cohabiters would experience even greater smoking risk relative to the different-sex married. Policy recommendations to reduce smoking disparities among same-sex and different-sex cohabiters are discussed. PMID:25346559

The trouble with sex differences.

PubMed

Eliot, Lise

2011-12-22

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.

Sex differences in chronic stress responses and Alzheimer's disease.

PubMed

Yan, Yan; Dominguez, Sky; Fisher, Daniel W; Dong, Hongxin

2018-02-01

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.

Sex differences in prenatal epigenetic programming of stress pathways.

PubMed

Bale, Tracy L

2011-07-01

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.

Sex Differences in Human and Animal Toxicology: Toxicokinetics

PubMed Central

Gochfeld, Michael

2016-01-01

Sex, the states of being female or male, potentially interacts with all xenobiotic exposures, both inadvertent and deliberate, and influences their toxicokinetics, 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. 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 FDA rules excluded women of child-bearing 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 adverse drug reactions than men, The Classic Sex Hormone Paradigm (gonadectomy and replacement) reveals significant interaction of sex and toxicokinetics 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. PMID:27895264

Gender and sex differences in job status and hypertension.

PubMed

Clougherty, Jane E; Eisen, Ellen A; Slade, Martin D; Kawachi, Ichiro; Cullen, Mark R

2011-01-01

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.

Sex-related differences in foot shape.

PubMed

Krauss, I; Grau, S; Mauch, M; Maiwald, C; Horstmann, T

2008-11-01

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.

Behavioural and cognitive sex/gender differences in autism spectrum condition and typically developing males and females.

PubMed

Hull, Laura; Mandy, William; Petrides, K V

2017-08-01

Studies assessing sex/gender differences in autism spectrum conditions often fail to include typically developing control groups. It is, therefore, unclear whether observed sex/gender differences reflect those found in the general population or are particular to autism spectrum conditions. A systematic search identified articles comparing behavioural and cognitive characteristics in males and females with and without an autism spectrum condition diagnosis. A total of 13 studies were included in meta-analyses of sex/gender differences in core autism spectrum condition symptoms (social/communication impairments and restricted/repetitive behaviours and interests) and intelligence quotient. A total of 20 studies were included in a qualitative review of sex/gender differences in additional autism spectrum condition symptoms. For core traits and intelligence quotient, sex/gender differences were comparable in autism spectrum conditions and typical samples. Some additional autism spectrum condition symptoms displayed different patterns of sex/gender differences in autism spectrum conditions and typically developing groups, including measures of executive function, empathising and systemising traits, internalising and externalising problems and play behaviours. Individuals with autism spectrum conditions display typical sex/gender differences in core autism spectrum condition traits, suggesting that diagnostic criteria based on these symptoms should take into account typical sex/gender differences. However, awareness of associated autism spectrum condition symptoms should include the possibility of different male and female phenotypes, to ensure those who do not fit the 'typical' autism spectrum condition presentation are not missed.

Sex Differences in the Brain.

ERIC Educational Resources Information Center

Kimura, Doreen

1992-01-01

Explores the neural and hormonal basis of human intellectual function that gives rise to sex differences in the brain. Discusses behavioral, neurological, endocrinological studies, and studies of the effects of hormones on brain functioning that show a relationship between cognitive variations and sex. (MCO)

Sex differences in acute kidney injury requiring dialysis.

PubMed

Neugarten, Joel; Golestaneh, Ladan; Kolhe, Nitin V

2018-06-08

Female sex has been included as a risk factor in models developed to predict the risk of acute kidney injury (AKI) associated with cardiac surgery, aminoglycoside nephrotoxicity and contrast-induced nephropathy. The commentary acompanying the Kidney Disease Improving Global Outcomes Clinical Practice Guideline for Acute Kidney Injury concludes that female sex is a shared susceptibility factor for acute kidney injury based on observations that female sex is associated with the development of hospital-acquired acute kidney injury. In contrast, female sex is reno-protective in animal models. In this context, we sought to examine the role of sex in hospital-associated acute kidney injury in greater detail. We utilized the Hospital Episode Statistics database to calculate the sex-stratified incidence of AKI requiring renal replacement therapy (AKI-D) among 194,157,726 hospital discharges reported for the years 1998-2013. In addition, we conducted a systematic review of the English literature to evaluate dialysis practices among men versus women with AKI. Hospitalized men were more likely to develop AKI-D than hospitalized women (OR 2.19 (2.15, 2.22) p < 0.0001). We found no evidence in the published literature that dialysis practices differ between men and women with AKI. Based on a population of hospitalized patients which is more than 3 times larger than all previously published cohorts reporting sex-stratified AKI data combined, we conclude that male sex is associated with an increased incidence of hospital-associated AKI-D. Our study is among the first reports to highlight the protective role of female gender in AKI.

Sex Differences in Vestibular/Ocular and Neurocognitive Outcomes After Sport-Related Concussion.

PubMed

Sufrinko, Alicia M; Mucha, Anne; Covassin, Tracey; Marchetti, Greg; Elbin, R J; Collins, Michael W; Kontos, Anthony P

2017-03-01

To examine sex differences in vestibular and oculomotor symptoms and impairment in athletes with sport-related concussion (SRC). The secondary purpose was to replicate previously reported sex differences in total concussion symptoms, and performance on neurocognitive and balance testing. Prospective cross-sectional study of consecutively enrolled clinic patients within 21 days of a SRC. Specialty Concussion Clinic. Included male (n = 36) and female (n = 28) athletes ages 9 to 18 years. Vestibular symptoms and impairment was measured with the Vestibular/Ocular Motor Screening (VOMS). Participants completed the Immediate Post-concussion Assessment and Cognitive Test (ImPACT), Post-concussion Symptom Scale (PCSS), and Balance Error Scoring System (BESS). Sex differences on clinical measures. Females had higher PCSS scores (P = 0.01) and greater VOMS vestibular ocular reflex (VOR) score (P = 0.01) compared with males. There were no sex differences on BESS or ImPACT. Total PCSS scores together with female sex accounted for 45% of the variance in VOR scores. Findings suggest higher VOR scores after SRC in female compared with male athletes. Findings did not extend to other components of the VOMS tool suggesting that sex differences may be specific to certain types of vestibular impairment after SRC. Additional research on the clinical significance of the current findings is needed.

Genes, Environments, and Sex Differences in Alcohol Research.

PubMed

Salvatore, Jessica E; Cho, Seung Bin; Dick, Danielle M

2017-07-01

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.

Sex differences in Parkinson's disease.

PubMed

Gillies, Glenda E; Pienaar, Ilse S; Vohra, Shiv; Qamhawi, Zahi

2014-08-01

Parkinson's disease (PD) displays a greater prevalence and earlier age at onset in men. This review addresses the concept that sex differences in PD are determined, largely, by biological sex differences in the NSDA system which, in turn, arise from hormonal, genetic and environmental influences. Current therapies for PD rely on dopamine replacement strategies to treat symptoms, and there is an urgent, unmet need for disease modifying agents. As a significant degree of neuroprotection against the early stages of clinical or experimental PD is seen, respectively, in human and rodent females compared with males, a better understanding of brain sex dimorphisms in the intact and injured NSDA system will shed light on mechanisms which have the potential to delay, or even halt, the progression of PD. Available evidence suggests that sex-specific, hormone-based therapeutic agents hold particular promise for developing treatments with optimal efficacy in men and women. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

Gender-stereotyping and cognitive sex differences in mixed- and same-sex groups.

PubMed

Hirnstein, Marco; Coloma Andrews, Lisa; Hausmann, Markus

2014-11-01

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.

Elevated Amygdala Perfusion Mediates Developmental Sex Differences in Trait Anxiety.

PubMed

Kaczkurkin, Antonia N; Moore, Tyler M; Ruparel, Kosha; Ciric, Rastko; Calkins, Monica E; Shinohara, Russell T; Elliott, Mark A; Hopson, Ryan; Roalf, David R; Vandekar, Simon N; Gennatas, Efstathios D; Wolf, Daniel H; Scott, J Cobb; Pine, Daniel S; Leibenluft, Ellen; Detre, John A; Foa, Edna B; Gur, Raquel E; Gur, Ruben C; Satterthwaite, Theodore D

2016-11-15

Adolescence is a critical period for emotional maturation and is a time when clinically significant symptoms of anxiety and depression increase, particularly in females. However, few studies relate developmental differences in symptoms of anxiety and depression to brain development. Cerebral blood flow is one brain phenotype that is known to have marked developmental sex differences. We investigated whether developmental sex differences in cerebral blood flow mediated sex differences in anxiety and depression symptoms by capitalizing on a large sample of 875 youths who completed cross-sectional imaging as part of the Philadelphia Neurodevelopmental Cohort. Perfusion was quantified on a voxelwise basis using arterial spin-labeled magnetic resonance imaging at 3T. Perfusion images were related to trait and state anxiety using general additive models with penalized splines, while controlling for gray matter density on a voxelwise basis. Clusters found to be related to anxiety were evaluated for interactions with age, sex, and puberty. Trait anxiety was associated with elevated perfusion in a network of regions including the amygdala, anterior insula, and fusiform cortex, even after accounting for prescan state anxiety. Notably, these relationships strengthened with age and the transition through puberty. Moreover, higher trait anxiety in postpubertal females was mediated by elevated perfusion of the left amygdala. Taken together, these results demonstrate that differences in the evolution of cerebral perfusion during adolescence may be a critical element of the affective neurobiological characteristics underlying sex differences in anxiety and mood symptoms. Copyright © 2016 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

Sex Differences in Adolescents' Relations with Grandparents.

ERIC Educational Resources Information Center

Baranowski, Marc D.

Sex roles and sex differences in grandparent-grandchild relationships have begun to attract the attention of researchers in the field of extended family relations. Male (N=184) and female (N=221) students of a rural Maine high school responded to a questionnaire designed to examine sex differences in interactions between adolescents and their…

Sex differences and stress across the lifespan

PubMed Central

Bale, Tracy L; Epperson, C Neill

2015-01-01

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

Sex differences and stress across the lifespan.

PubMed

Bale, Tracy L; Epperson, C Neill

2015-10-01

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.

Sex differences in mental rotation with polygons of different complexity: Do men utilize holistic processes whereas women prefer piecemeal ones?

PubMed

Heil, Martin; Jansen-Osmann, Petra

2008-05-01

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.

Maternal Touch Moderates Sex Differences in Juvenile Social Play Behavior

PubMed Central

Edelmann, Michelle N.; Demers, Catherine H.; Auger, Anthony P.

2013-01-01

Additional somatosensory contact of preterm human infants improves a variety of developmental assessment scores, but less is known about its lasting consequences. In rodents, maternal contact may influence the programming of juvenile social play behavior. Therefore, we used a paradigm where we can control the levels of somatosensory contact associated with maternal care. We find that additional somatosensory contact of offspring can have lasting consequences on juvenile social play behavior in a sex-dependent manner. Specifically, additional somatosensory stimuli reduced male social play behavior, but did not change female play behavior. We then examined if this additional infant contact altered some neurobiological substrates associated with play within the juvenile amygdala. Control males had lower levels of 5HT2a receptor mRNA levels contrasted to females; however, similar to its sex-dependent effect on juvenile social play, males that received additional somatosensory contact had higher serotonin 5HT2a receptor mRNA levels than control males. No difference was found in females. As serotonin signaling typically opposes juvenile play behavior, these data suggest that maternal touch can program lasting differences in juvenile social play and 5HT2a receptors mRNA levels within the juvenile amygdala. PMID:23460849

Sex/Gender Differences and Autism: Setting the Scene for Future Research

PubMed Central

Lai, Meng-Chuan; Lombardo, Michael V.; Auyeung, Bonnie; Chakrabarti, Bhismadev; Baron-Cohen, Simon

2015-01-01

Objective The relationship between sex/gender differences and autism has attracted a variety of research ranging from clinical and neurobiological to etiological, stimulated by the male bias in autism prevalence. Findings are complex and do not always relate to each other in a straightforward manner. Distinct but interlinked questions on the relationship between sex/gender differences and autism remain underaddressed. To better understand the implications from existing research and to help design future studies, we propose a 4-level conceptual framework to clarify the embedded themes. Method We searched PubMed for publications before September 2014 using search terms “‘sex OR gender OR females’ AND autism.” A total of 1,906 articles were screened for relevance, along with publications identified via additional literature reviews, resulting in 329 articles that were reviewed. Results Level 1, “Nosological and diagnostic challenges,” concerns the question, “How should autism be defined and diagnosed in males and females?” Level 2, “Sex/gender-independent and sex/gender-dependent characteristics,” addresses the question, “What are the similarities and differences between males and females with autism?” Level 3, “General models of etiology: liability and threshold,” asks the question, “How is the liability for developing autism linked to sex/gender?” Level 4, “Specific etiological–developmental mechanisms,” focuses on the question, “What etiological–developmental mechanisms of autism are implicated by sex/gender and/or sexual/gender differentiation?” Conclusions Using this conceptual framework, findings can be more clearly summarized, and the implications of the links between findings from different levels can become clearer. Based on this 4-level framework, we suggest future research directions, methodology, and specific topics in sex/gender differences and autism. PMID:25524786

Sex differences in the processing of flankers.

PubMed

Stoet, Gijsbert

2010-04-01

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

Sex differences in adipose tissue

PubMed Central

Fuente-Martín, Esther; Argente-Arizón, Pilar; Ros, Purificación; Argente, Jesús; Chowen, Julie A

2013-01-01

Obesity and its associated secondary complications are active areas of investigation in search of effective treatments. As a result of this intensified research numerous differences between males and females at all levels of metabolic control have come to the forefront. These differences include not only the amount and distribution of adipose tissue, but also differences in its metabolic capacity and functions between the sexes. Here, we review some of the recent advances in our understanding of these dimorphisms and emphasize the fact that these differences between males and females must be taken into consideration in hopes of obtaining successful treatments for both sexes. PMID:23991358

Sex differences in sensation-seeking: a meta-analysis.

PubMed

Cross, Catharine P; Cyrenne, De-Laine M; Brown, Gillian R

2013-01-01

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.

Sex differences in the effect of aging on dry eye disease.

PubMed

Ahn, Jong Ho; Choi, Yoon-Hyeong; Paik, Hae Jung; Kim, Mee Kum; Wee, Won Ryang; Kim, Dong Hyun

2017-01-01

Aging is a major risk factor in dry eye disease (DED), and understanding sexual differences is very important in biomedical research. However, there is little information about sex differences in the effect of aging on DED. We investigated sex differences in the effect of aging and other risk factors for DED. This study included data of 16,824 adults from the Korea National Health and Nutrition Examination Survey (2010-2012), which is a population-based cross-sectional survey. DED was defined as the presence of frequent ocular dryness or a previous diagnosis by an ophthalmologist. Basic sociodemographic factors and previously known risk factors for DED were included in the analyses. Linear regression modeling and multivariate logistic regression modeling were used to compare the sex differences in the effect of risk factors for DED; we additionally performed tests for interactions between sex and other risk factors for DED in logistic regression models. In our linear regression models, the prevalence of DED symptoms in men increased with age ( R =0.311, P =0.012); however, there was no association between aging and DED in women ( P >0.05). Multivariate logistic regression analyses showed that aging in men was not associated with DED (DED symptoms/diagnosis: odds ratio [OR] =1.01/1.04, each P >0.05), while aging in women was protectively associated with DED (DED symptoms/diagnosis: OR =0.94/0.91, P =0.011/0.003). Previous ocular surgery was significantly associated with DED in both men and women (men/women: OR =2.45/1.77 [DED symptoms] and 3.17/2.05 [DED diagnosis], each P <0.001). Tests for interactions of sex revealed significantly different aging × sex and previous ocular surgery × sex interactions ( P for interaction of sex: DED symptoms/diagnosis - 0.044/0.011 [age] and 0.012/0.006 [previous ocular surgery]). There were distinct sex differences in the effect of aging on DED in the Korean population. DED following ocular surgery also showed sexually different

Sex Ideologies in China: Examining Interprovince Differences.

PubMed

Hu, Yang

2016-01-01

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.

Sex Differences in the Adolescent Brain

ERIC Educational Resources Information Center

Lenroot, Rhoshel K.; Giedd, Jay N.

2010-01-01

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…

Sex differences in the association between infant markers and later autistic traits.

PubMed

Bedford, Rachael; Jones, Emily J H; Johnson, Mark H; Pickles, Andrew; Charman, Tony; Gliga, Teodora

2016-01-01

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.

Sex Differences in Mortality Following Acute Coronary Syndromes

PubMed Central

Berger, Jeffrey S.; Elliott, Laine; Gallup, Dianne; Roe, Matthew; Granger, Christopher B.; Armstrong, Paul W.; Simes, R. John; White, Harvey D.; Van de Werf, Frans; Topol, Eric J.; Hochman, Judith S.; Newby, L. Kristin; Harrington, Robert A.; Califf, Robert M; Becker, Richard C.; Douglas, Pamela S.

2009-01-01

Context There is conflicting information about whether sex-differences modulate short-term mortality following acute coronary syndromes (ACS). Objective To investigate the relationship between sex and 30-day mortality in ACS, and determine whether this relationship is modified by clinical syndrome or coronary anatomy using a large database across the spectrum of ACS and adjusting for potentially confounding clinical covariates. Design Setting and Participants Data from 11 ACS trials from 1993 to 2006 were pooled. Of 136,247 patients, 38,048 (28%) were women; 102,004 (26% women) STEMI, 14,466 (29% women) NSTEMI and 19,777 (40% women) unstable angina (UA). Main Outcome Measure Thirty-day mortality following ACS. Results Mortality at 30 days was 9.6% in women and 5.3% in men (odds ratio [OR] 1.91, 95% confidence interval [CI] 1.83–2.00). After multivariable adjustment, mortality was not significantly different between women and men (adjusted OR 1.06, 95% CI 0.99–1.15). Importantly, a significant sex by type of ACS interaction was demonstrated (P<0.001). In STEMI, 30-day mortality was higher among women (adjusted OR 1.15, 95% CI 1.06–1.24), whereas NSTEMI (adjusted OR 0.77, 95% CI 0.63–0.95), and UA mortality was lower among women (adjusted OR 0.55, 95% CI 0.43–0.70). In a cohort of 35,128 patients with angiographic data, women more often had non-obstructive (15% vs. 8%,) and less often had 2-vessel (25% vs. 28%) and 3-vessel (23% vs. 26%) coronary disease regardless of ACS type. After additional adjustment for angiographic disease severity, 30-day mortality among women was not significantly different than men, regardless of ACS type. The relationship between sex and 30-day mortality was similar across the levels of angiographic disease severity (p-value for interaction =0.70), Conclusions Sex-based differences exist in 30-day mortality among ACS patients and vary depending on clinical presentation. However, these differences are markedly attenuated following

Sex differences in mortality following acute coronary syndromes.

PubMed

Berger, Jeffrey S; Elliott, Laine; Gallup, Dianne; Roe, Matthew; Granger, Christopher B; Armstrong, Paul W; Simes, R John; White, Harvey D; Van de Werf, Frans; Topol, Eric J; Hochman, Judith S; Newby, L Kristin; Harrington, Robert A; Califf, Robert M; Becker, Richard C; Douglas, Pamela S

2009-08-26

Conflicting information exists about whether sex differences modulate short-term mortality following acute coronary syndromes (ACS). To investigate the relationship between sex and 30-day mortality in ACS, and to determine whether this relationship was modified by clinical syndrome or coronary anatomy using a large database across the spectrum of ACS and adjusting for potentially confounding clinical covariates. A convenience sample of patients pooled from 11 independent, international, randomized ACS clinical trials between 1993 and 2006 whose databases are maintained at the Duke Clinical Research Institute, Durham, North Carolina. Of 136 247 patients, 38 048 (28%) were women; 102 004 (26% women) with ST-segment elevation myocardial infarction (STEMI), 14 466 (29% women) with non-STEMI (NSTEMI), and 19 777 (40% women) with unstable angina. Thirty-day mortality following ACS. Thirty-day mortality was 9.6% in women and 5.3% in men (odds ratio [OR], 1.91; 95% confidence interval [CI], 1.83-2.00). After multivariable adjustment, mortality was not significantly different between women and men (adjusted OR, 1.06; 95% CI, 0.99-1.15). A significant sex by type of ACS interaction was demonstrated (P < .001). In STEMI, 30-day mortality was higher among women (adjusted OR, 1.15; 95% CI, 1.06-1.24), whereas in NSTEMI (adjusted OR, 0.77; 95% CI, 0.63-0.95) and unstable angina, mortality was lower among women (adjusted OR, 0.55; 95% CI, 0.43-0.70). In a cohort of 35 128 patients with angiographic data, women more often had nonobstructive (15% vs 8%) and less often had 2-vessel (25% vs 28%) and 3-vessel (23% vs 26%) coronary disease, regardless of ACS type. After additional adjustment for angiographic disease severity, 30-day mortality among women was not significantly different than men, regardless of ACS type. The relationship between sex and 30-day mortality was similar across the levels of angiographic disease severity (P for interaction = .70). Sex-based differences existed

Sex differences in the psychopharmacological treatment of depression.

PubMed

Sramek, John J; Murphy, Michael F; Cutler, Neal R

2016-12-01

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.

Social Status Affects the Degree of Sex Difference in the Songbird Brain

PubMed Central

Voigt, Cornelia; Gahr, Manfred

2011-01-01

It is thought that neural sex differences are functionally related to sex differences in the behaviour of vertebrates. A prominent example is the song control system of songbirds. Inter-specific comparisons have led to the hypothesis that sex differences in song nuclei size correlate with sex differences in song behaviour. However, only few species with similar song behaviour in both sexes have been investigated and not all data fit the hypothesis. We investigated the proposed structure – function relationship in a cooperatively breeding and duetting songbird, the white-browed sparrow weaver (Plocepasser mahali). This species lives in groups of 2–10 individuals, with a dominant breeding pair and male and female subordinates. While all male and female group members sing duet and chorus song, a male, once it has reached the dominant position in the group, sings an additional type of song that comprises a distinct and large syllable repertoire. Here we show for both types of male – female comparisons a male-biased sex difference in neuroanatomy of areas of the song production pathway (HVC and RA) that does not correlate with the observed polymorphism in song behaviour. In contrast, in situ hybridisation of mRNA of selected genes expressed in the song nucleus HVC reveals a gene expression pattern that is either similar between sexes in female – subordinate male comparisons or female-biased in female – dominant male comparisons. Thus, the polymorphic gene expression pattern would fit the sex- and status-related song behaviour. However, this implies that once a male has become dominant it produces the duetting song with a different neural phenotype than subordinate males. PMID:21687671

Sex Differences Reappraised: A Rebuttal

ERIC Educational Resources Information Center

Tolor, Alexander; Brannigan, Gary G.

1975-01-01

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…

Sex Differences in School Learning.

ERIC Educational Resources Information Center

Shannon, Albert S., Ed.

1982-01-01

Sex differences in school learning are examined with a focus on how the variable of gender affects the teaching, learning, development, and behavior of children. The initial entries in this collection of articles focus on reading: the reading interests of girls and boys, sex bias and stereotyping in reading tests, and the influence of gender,…

Sex differences in emotional contexts modulation on response inhibition.

PubMed

Ramos-Loyo, Julieta; Angulo-Chavira, Armando; Llamas-Alonso, Luis A; González-Garrido, Andrés A

2016-10-01

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.

Sex differences in depression during pregnancy and the postpartum period

PubMed Central

Comasco, Erika; Georgakis, Marios K.; Skalkidou, Alkistis

2016-01-01

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. PMID:27870443

Role of Kidneys in Sex Differences in Angiotensin II-Induced Hypertension.

PubMed

Wang, Lei; Wang, Ximing; Qu, Helena Y; Jiang, Shan; Zhang, Jie; Fu, Liying; Buggs, Jacentha; Pang, Bo; Wei, Jin; Liu, Ruisheng

2017-12-01

The significance of kidneys in regulation of sodium and water balance and hemodynamics has been demonstrated both in patients and animal models. In the present study, we tested our hypothesis that kidneys play an essential role in control of sex differences in angiotensin II (Ang II)-dependent hypertension. Kidney transplantations (KTXs) were performed between male (M) and female (F) C57BL/6 mice (donor→recipient: F→F, M→M, F→M, and M→F). Radiotelemetry transmitters were implanted for measurement of mean arterial pressure during the infusion of Ang II (600 ng·kg -1 ·min -1 ). Gene expressions and inflammatory responses in the transplanted grafts were assessed. We found that same-sex-KTX mice still exhibited sex differences in Ang II-dependent hypertension (31.3±0.8 mm Hg in M→M versus 12.2±0.6 mm Hg in F→F), which were reduced between males and females when they received kidneys of the opposite sex (32.9±1 mm Hg in M→F versus 22.3±0.7 mm Hg in F→M). The sex differences in gene expressions, including AT 1 R (angiotensin II receptor, type 1), AT 1 R/AT 2 R, ET-1 (endothelin-1), ETA (endothelin receptor type A), NHE3 (sodium-hydrogen exchanger 3), α-ENaC (α-epithelial sodium channel), and γ-ENaC, were unaltered in same-sex KTXs and much lessened in cross-sex KTXs. In addition, the cross-sex KTXs exhibited more robust inflammatory responses reflected by higher expression of IL-6 (interleukin 6), TNFα (tumor necrosis factor α), and KC (keratinocyte-derived chemokine) than same-sex KTX. Our results indicate that kidneys play an essential role in sex differences of Ang II-dependent hypertension. KTX of male kidneys to females augmented the blood pressure response, whereas KTX of female kidneys to males attenuated the blood pressure response. The host's extrarenal systems modulate expressions of many genes and inflammatory response, which may also contribute to the sex differences in blood pressure regulation. © 2017 American Heart

Sex differences in nicotine preference.

PubMed

Pogun, Sakire; Yararbas, Gorkem; Nesil, Tanseli; Kanit, Lutfiye

2017-01-02

Smoking is the major cause of preventable deaths worldwide, and although there is a decline in overall smoking prevalence in developed countries, the decline in women is less pronounced than in men. Women become dependent faster and experience greater difficulties in quitting. Similar trends have been observed in animal models of nicotine/tobacco addiction. Individual differences in vulnerability to drug abuse are also observed in nicotine/tobacco addiction and point to the importance of sex differences. This Review, summarizes findings from three experimental approaches used to depict nicotine preference in animal models, intravenous and oral nicotine self-administration and nicotine-induced conditioned place preference. Nicotine preference is considered to be reflected in the animal's motivation to administer the drug (intravenously or orally) or to prefer an environment paired with the presence of the drug (conditioned place preference). These approaches all point to the importance of sex and age of the subjects; the preference of females and adolescents appear to be more pronounced than that of males and adults, respectively. A closer look at these factors will help us understand the mechanisms that underlie nicotine addiction and develop strategies to cope. Ignoring sex differences and reaching conclusions based only on studies using male subjects has resulted in erroneous generalizations in the past. Sex differences in nicotine preference have been clearly documented, and awareness on this aspect of nicotine dependence will significantly impact our success in translational research. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Preschoolers' Mental Rotation: Sex Differences in Hemispheric Asymmetry

ERIC Educational Resources Information Center

Hahn, Nicola; Jansen, Petra; Heil, Martin

2010-01-01

Mental rotation performance has been found to produce one of the largest sex differences in cognition accompanied by sex differences in functional cerebral asymmetry. Although sex differences in mental rotation performance can be reliably demonstrated as early as age 5 years old, that is, long before puberty, no data exist as to whether…

Sex differences in cognitive impairment and Alzheimer's disease.

PubMed

Li, Rena; Singh, Meharvan

2014-08-01

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.

Sex Differences in Parietal Lobe Morphology: Relationship to Mental Rotation Performance

ERIC Educational Resources Information Center

Koscik, Tim; O'Leary, Dan; Moser, David J.; Andreasen, Nancy C.; Nopoulos, Peg

2009-01-01

Structural magnetic resonance imaging (MRI) studies of the human brain have reported evidence for sexual dimorphism. In addition to sex differences in overall cerebral volume, differences in the proportion of gray matter (GM) to white matter (WM) volume have been observed, particularly in the parietal lobe. To our knowledge there have been no…

Sex Differences in Music: A Female Advantage at Recognizing Familiar Melodies.

PubMed

Miles, Scott A; Miranda, Robbin A; Ullman, Michael T

2016-01-01

Although sex differences have been observed in various cognitive domains, there has been little work examining sex differences in the cognition of music. We tested the prediction that women would be better than men at recognizing familiar melodies, since memories of specific melodies are likely to be learned (at least in part) by declarative memory, which shows female advantages. Participants were 24 men and 24 women, with half musicians and half non-musicians in each group. The two groups were matched on age, education, and various measures of musical training. Participants were presented with well-known and novel melodies, and were asked to indicate their recognition of familiar melodies as rapidly as possible. The women were significantly faster than the men in responding, with a large effect size. The female advantage held across musicians and non-musicians, and across melodies with and without commonly associated lyrics, as evidenced by an absence of interactions between sex and these factors. Additionally, the results did not seem to be explained by sex differences in response biases, or in basic motor processes as tested in a control task. Though caution is warranted given that this is the first study to examine sex differences in familiar melody recognition, the results are consistent with the hypothesis motivating our prediction, namely that declarative memory underlies knowledge about music (particularly about familiar melodies), and that the female advantage at declarative memory may thus lead to female advantages in music cognition (particularly at familiar melody recognition). Additionally, the findings argue against the view that female advantages at tasks involving verbal (or verbalizable) material are due solely to a sex difference specific to the verbal domain. Further, the results may help explain previously reported cognitive commonalities between music and language: since declarative memory also underlies language, such commonalities may be

Perils and pitfalls of reporting sex differences

PubMed Central

Maney, Donna L.

2016-01-01

The idea of sex differences in the brain both fascinates and inflames the public. As a result, the communication and public discussion of new findings is particularly vulnerable to logical leaps and pseudoscience. A new US National Institutes of Health policy to consider both sexes in almost all preclinical research will increase the number of reported sex differences and thus the risk that research in this important area will be misinterpreted and misrepresented. In this article, I consider ways in which we might reduce that risk, for example, by (i) employing statistical tests that reveal the extent to which sex explains variation, rather than whether or not the sexes ‘differ’, (ii) properly characterizing the frequency distributions of scores or dependent measures, which nearly always overlap, and (iii) avoiding speculative functional or evolutionary explanations for sex-based variation, which usually invoke logical fallacies and perpetuate sex stereotypes. Ultimately, the factor of sex should be viewed as an imperfect, temporary proxy for yet-unknown factors, such as hormones or sex-linked genes, that explain variation better than sex. As scientists, we should be interested in discovering and understanding the true sources of variation, which will be more informative in the development of clinical treatments. PMID:26833839

Sex Differences in Behavioral Dyscontrol: Role in Drug Addiction and Novel Treatments

PubMed Central

Carroll, Marilyn E.; Smethells, John R.

2016-01-01

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, is discussed as major determinants of drug addiction. Behavioral dyscontrol during adolescence is also an important consideration, as this is the time of onset for drug addiction. These vulnerability factors additively increase drug-abuse vulnerability, and they are integral aspects of addiction that covary and interact with sex differences. Sex differences in treatments for drug addiction are also reviewed in terms of their ability to modify the behavioral dyscontrol that underlies addictive behavior. Customized treatments to reduce behavioral dyscontrol are discussed, such as (1) using natural consequences such as non-drug rewards (e.g., exercise) to maintain abstinence, or using punishment as a consequence for drug use, (2) targeting factors that underlie behavioral dyscontrol, such as impulsivity or anxiety, by repurposing medications to relieve these underlying conditions, and (3) combining two or more novel behavioral or pharmacological treatments to produce additive reductions in drug seeking. Recent published work has indicated that factors contributing to behavioral dyscontrol are an important target for advancing our knowledge on the etiology of drug abuse, intervening with the drug addiction process and developing novel treatments. PMID:26903885

Sex Differences in Behavioral Dyscontrol: Role in Drug Addiction and Novel Treatments.

PubMed

Carroll, Marilyn E; Smethells, John R

2015-01-01

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, is discussed as major determinants of drug addiction. Behavioral dyscontrol during adolescence is also an important consideration, as this is the time of onset for drug addiction. These vulnerability factors additively increase drug-abuse vulnerability, and they are integral aspects of addiction that covary and interact with sex differences. Sex differences in treatments for drug addiction are also reviewed in terms of their ability to modify the behavioral dyscontrol that underlies addictive behavior. Customized treatments to reduce behavioral dyscontrol are discussed, such as (1) using natural consequences such as non-drug rewards (e.g., exercise) to maintain abstinence, or using punishment as a consequence for drug use, (2) targeting factors that underlie behavioral dyscontrol, such as impulsivity or anxiety, by repurposing medications to relieve these underlying conditions, and (3) combining two or more novel behavioral or pharmacological treatments to produce additive reductions in drug seeking. Recent published work has indicated that factors contributing to behavioral dyscontrol are an important target for advancing our knowledge on the etiology of drug abuse, intervening with the drug addiction process and developing novel treatments.

The Co-Development of Skill at and Preference for Use of Retrieval-Based Processes for Solving Addition Problems: Individual and Sex Differences from First to Sixth Grade

PubMed Central

Bailey, Drew H.; Littlefield, Andrew; Geary, David C.

2012-01-01

The ability to retrieve basic arithmetic facts from long-term memory contributes to individual and perhaps sex differences in mathematics achievement. The current study tracked the co-development of preference for using retrieval over other strategies to solve single-digit addition problems, independent of accuracy, and skilled use of retrieval (i.e., accuracy and RT) from first to sixth grade, inclusive (n = 311). Accurate retrieval in first grade was related to working memory capacity and intelligence and predicted a preference for retrieval in second grade. In later grades, the relation between skill and preference changed such that preference in one grade predicted accuracy and RT in the next, as RT and accuracy continued to predict future gains in preference. In comparison to girls, boys had a consistent preference for retrieval over other strategies and had faster retrieval speeds, but the sex difference in retrieval accuracy varied across grades. Results indicate ability influences early skilled retrieval but both practice and skill influence each other in a feedback loop later in development, and provide insights into the source of the sex difference in problem solving approaches. PMID:22704036

Sex differences in cardiovascular epigenetics-a systematic review.

PubMed

Hartman, Robin J G; Huisman, Sarah E; den Ruijter, Hester M

2018-05-23

Differences in cardiovascular diseases are evident in men and women throughout life and are mainly attributed to the presence of sex hormones and chromosomes. Epigenetic mechanisms drive the regulation of the biological processes that may lead to CVD and are possibly influenced by sex. In order to gain an overview of the status quo on sex differences in cardiovascular epigenetics, we performed a systematic review. A systematic search was performed on PubMed and Embase for studies mentioning cardiovascular disease, epigenetics, and anything related to sex differences. The search returned 3071 publications to be screened. Primary included publications focused on cardiovascular and epigenetics research. Subsequently, papers were assessed for including both sexes in their studies and checked for appropriate sex stratification of results. Two independent screeners identified 75 papers in the proper domains that had included both sexes. Only 17% (13 papers out of 75) of these publications stratified some of their data according to sex. All remaining papers focused on DNA methylation solely as an epigenetic mechanism. Of the excluded papers that included only one sex, 86% (24 out 28) studied males, while 14% (4 out of 28) studied females. Our overview indicates that the majority of studies into cardiovascular epigenetics do not show their data stratified by sex, despite the well-known sex differences in CVD. All included and sex-stratified papers focus on DNA methylation, indicating that a lot of ground is still to gain regarding other epigenetic mechanisms, like chromatin architecture, and histone modifications. More attention to sex in epigenetic studies is warranted as such integration will advance our understanding of cardiovascular disease mechanisms in men and women.

Sexual regret: evidence for evolved sex differences.

PubMed

Galperin, Andrew; Haselton, Martie G; Frederick, David A; Poore, Joshua; von Hippel, William; Buss, David M; Gonzaga, Gian C

2013-10-01

Regret and anticipated regret enhance decision quality by helping people avoid making and repeating mistakes. Some of people's most intense regrets concern sexual decisions. We hypothesized evolved sex differences in women's and men's experiences of sexual regret. Because of women's higher obligatory costs of reproduction throughout evolutionary history, we hypothesized that sexual actions, particularly those involving casual sex, would be regretted more intensely by women than by men. In contrast, because missed sexual opportunities historically carried higher reproductive fitness costs for men than for women, we hypothesized that poorly chosen sexual inactions would be regretted more by men than by women. Across three studies (Ns = 200, 395, and 24,230), we tested these hypotheses using free responses, written scenarios, detailed checklists, and Internet sampling to achieve participant diversity, including diversity in sexual orientation. Across all data sources, results supported predicted psychological sex differences and these differences were localized in casual sex contexts. These findings are consistent with the notion that the psychology of sexual regret was shaped by recurrent sex differences in selection pressures operating over deep time.

Why size matters: differences in brain volume account for apparent sex differences in callosal anatomy: the sexual dimorphism of the corpus callosum.

PubMed

Luders, Eileen; Toga, Arthur W; Thompson, Paul M

2014-01-01

Numerous studies have demonstrated a sexual dimorphism of the human corpus callosum. However, the question remains if sex differences in brain size, which typically is larger in men than in women, or biological sex per se account for the apparent sex differences in callosal morphology. Comparing callosal dimensions between men and women matched for overall brain size may clarify the true contribution of biological sex, as any observed group difference should indicate pure sex effects. We thus examined callosal morphology in 24 male and 24 female brains carefully matched for overall size. In addition, we selected 24 extremely large male brains and 24 extremely small female brains to explore if observed sex effects might vary depending on the degree to which male and female groups differed in brain size. Using the individual T1-weighted brain images (n=96), we delineated the corpus callosum at midline and applied a well-validated surface-based mesh-modeling approach to compare callosal thickness at 100 equidistant points between groups determined by brain size and sex. The corpus callosum was always thicker in men than in women. However, this callosal sex difference was strongly determined by the cerebral sex difference overall. That is, the larger the discrepancy in brain size between men and women, the more pronounced the sex difference in callosal thickness, with hardly any callosal differences remaining between brain-size matched men and women. Altogether, these findings suggest that individual differences in brain size account for apparent sex differences in the anatomy of the corpus callosum. © 2013.

Sex selection: treating different cases differently.

PubMed

Dickens, B M; Serour, G I; Cook, R J; Qiu, R-Z

2005-08-01

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.

Sex-specific strategy use and global-local processing: a perspective toward integrating sex differences in cognition.

PubMed

Pletzer, Belinda

2014-01-01

This article reviews the literature on sex-specific strategy use in cognitive tasks with the aim to carve out a link between sex differences in different cognitive tasks. I conclude that male strategies are commonly holistic and oriented toward global stimulus aspects, while female strategies are commonly decomposed and oriented toward local stimulus aspects. Thus, the strategies observed in different tasks, may depend on sex differences in attentional focus and hence sex differences in global-local processing. I hypothesize that strategy use may be sex hormone dependent and hence subject to change over the menstrual cycle as evidenced by findings in global-local processing and emotional memory. Furthermore, I propose sex hormonal modulation of hemispheric asymmetries as one possible neural substrate for this theory, thereby building on older theories, emphasizing the importance of sex differences in brain lateralization. The ideas described in the current article represent a perspective toward a unifying approach to the study of sex differences in cognition and their neural correlates.

Childhood Adversity, Daily Stress, and Marital Strain in Same-Sex and Different-Sex Marriages

PubMed Central

Donnelly, Rachel; Umberson, Debra; Kroeger, Rhiannon A.

2017-01-01

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.

Sex-based Differences in Common Sports Injuries.

PubMed

Carter, Cordelia W; Ireland, Mary Lloyd; Johnson, Anthony E; Levine, William N; Martin, Scott; Bedi, Asheesh; Matzkin, Elizabeth G

2018-05-28

The patient's sex plays an important role in mediating the risk for, and experience of, disease. Injuries of the musculoskeletal system are no exception to this phenomenon. Increasing evidence shows that the incidence, clinical presentation, and treatment outcomes for male and female patients with common sports injuries may vary widely. Stress fracture, which is associated with the female athlete triad, is a sports injury with known sex-based differences. Other common sports-related injuries may also have distinct sex-based differences. Understanding these differences is important to optimize each patient's musculoskeletal care.

Sex differences in the locus coeruleus-norepinephrine system and its regulation by stress.

PubMed

Bangasser, Debra A; Wiersielis, Kimberly R; Khantsis, Sabina

2016-06-15

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.

The Relevance of Sex Differences in Performance Fatigability

PubMed Central

Hunter, Sandra K.

2016-01-01

Performance fatigability differs between men and women for a range of fatiguing tasks. Women are usually less fatigable than men and this is most widely described for isometric fatiguing contractions, and some dynamic tasks. The sex difference in fatigability is specific to the task demands so that one mechanism is not universal, including any sex differences in skeletal muscle physiology, muscle perfusion and voluntary activation. However, there are substantial knowledge gaps about the task dependency of the sex differences in fatigability, the involved mechanisms and the relevance to clinical populations and with advanced age. The knowledge gaps are in part due to the significant deficits in the number of women included in performance fatigability studies despite a gradual increase in the inclusion of women over the last 20 years. Therefore, this review 1) provides a rationale for the limited knowledge about sex differences in performance fatigability, 2) summarizes the current knowledge on sex differences in fatigability and the potential mechanisms across a range of tasks, 3) highlights emerging areas of opportunity in clinical populations, and 4) suggests strategies to close the knowledge gap and understanding the relevance of sex differences in performance fatigability. The limited understanding about sex differences in fatigability in healthy and clinical populations, presents as a field ripe with opportunity for high impact studies. Such studies will inform on the limitations of men and women during athletic endeavors, ergonomic tasks and daily activities. Because fatigability is required for effective neuromuscular adaptation, sex differences in fatigability studies will also inform on optimal strategies for training and rehabilitation in both men and women. PMID:27015385

A Comparison of Intimate Partner Violence Strangulation Between Same-Sex and Different-Sex Couples.

PubMed

Messing, Jill T; Thomas, Kristie A; Ward-Lasher, Allison L; Brewer, Nathan Q

2018-03-01

Strangulation is a common and dangerous form of intimate partner violence (IPV). Nonfatal strangulation is a risk factor for homicide; can lead to severe, long-term physical and mental health sequelae; and can be an effective strategy of coercion and control. To date, research has not examined strangulation within same-sex couples. The objective of this cross-sectional, observational research is to identify whether and to what extent the detection of strangulation and coercive control differs between same-sex and different-sex couples in police reports of IPV. Data ( n = 2,207) were obtained from a single police department in the southwest United States (2011-2013). Bivariate analyses examined differences in victim and offender demographics, victim injury, violence, and coercive controlling behaviors between same-sex (male-male and female-female) and different-sex couples (female victim-male offender). Logistic regression was used to examine associations between strangulation, victim and offender demographics, coercive controlling behaviors, and couple configuration. Strangulation was reported significantly more often in different-sex (9.8%) than in female and male same-sex couple cases (5.2% and 5.3%, respectively; p < .05). Injury, however, was reported more frequently in same-sex than in different-sex couples ( p < .05). Couple configuration ( p < .05), coercive control ( p < .05), and injury ( p < .05) significantly predict strangulation. Findings suggest that nonfatal strangulation occurs within at least a minority of same-sex couples; it is possible that underdetection by law enforcement makes it appear less common than it actually is. Regardless of couple configuration, timely identification of strangulation and subsequent referral to medical and social service providers is essential for preventing repeated strangulation, life-threatening injury, and the long-term health effects of strangulation.

Gender and the Stability of Same-Sex and Different-Sex Relationships Among Young Adults.

PubMed

Joyner, Kara; Manning, Wendy; Bogle, Ryan

2017-12-01

Most research on the stability of adult relationships has focused on coresidential (cohabiting or married) unions and estimates rates of dissolution for the period of coresidence. Studies examining how the stability of coresidential unions differs by sex composition have typically found that same-sex female couples have higher rates of dissolution than same-sex male couples and different-sex couples. We argue that the more elevated rates of dissolution for same-sex female couples are a by-product of the focus on coresidential unions. We use data from the National Longitudinal Study of Adolescent to Adult Health to compare rates of dissolution based on the total duration of romantic and sexual relationships for same-sex male couples, same-sex female couples, and different-sex couples. Results from hazard models that track the stability of young adult relationships from the time they are formed demonstrate that male couples have substantially higher dissolution rates than female couples and different-sex couples. Results based on models restricted to the period of coresidence corroborate the counterintuitive finding from earlier studies that female couples have the highest rates of dissolving coresidential unions. This study underlines the importance of comparisons between these couple types for a better understanding of the role that institutions and gender play in the stability of contemporary relationships.

Sex-related differences in striatal dopaminergic system after traumatic brain injury.

PubMed

Xu, Xiupeng; Cao, Shengwu; Chao, Honglu; Liu, Yinlong; Ji, Jing

2016-06-01

Several studies have demonstrated alterations in the dopamine (DA) system after traumatic brain injury (TBI). Additionally, the existence of significant sex-related differences in the dopaminergic system has long been recognized. Accordingly, the purpose of the present study was to investigate whether TBI would differentially alter, in female and male mice, the expression and the function of the striatal vesicular monoamine transporter-2 (VMAT-2), an important DA transporter. After controlled cortical impact (CCI) injury, female mice showed significantly lower striatal DA concentrations and K(+)-evoked DA output. By contrast, no significant sex-related differences were observed in the mRNA and protein levels of striatal dopamine transporter (DAT) and VMAT-2 and the methamphetamine (MA)-evoked DA output. These results demonstrated clear sex-related differences in striatal VMAT-2 function in response to TBI and suggested that female mice may be more sensitive to the TBI-induced inhibition of the VMAT-2 function, as indicated by the greater degree of deficits observed when the VMAT-2 DA-storage function was inhibited by TBI. Moreover, the TBI-induced suppression of locomotion was more pronounced than female mice. Such findings highlight the need for sex-specific considerations when examining differences among brain injury conditions. Copyright © 2016 Elsevier Inc. All rights reserved.

RAS and sex differences in diabetic nephropathy.

PubMed

Clotet, Sergi; Riera, Marta; Pascual, Julio; Soler, Maria José

2016-03-09

The incidence and progression of kidney diseases are influenced by sex. The renin-angiotensin system (RAS) is an important regulator of cardiovascular and renal function. Sex differences in the renal response to RAS blockade have been demonstrated. Circulating and renal RAS has been shown to be altered in type 1 and type 2 diabetes; this enzymatic cascade plays a critical role in the development of diabetic nephropathy (DN). Angiotensin converting enzyme (ACE) and ACE2 are differentially regulated depending on its localization within the diabetic kidney. Furthermore, clinical and experimental studies have shown that circulating levels of sex hormones are clearly modulated in the context of diabetes, suggesting that sex-dependent RAS regulation may be also be affected in these individuals. The effect of sex hormones on circulating and renal RAS may be involved in the sex differences observed in DN progression. In this paper we will review the influence of sex hormones on RAS expression and its relation to diabetic kidney disease. A better understanding of the sex dimorphism on RAS might provide a new approach for diabetic kidney disease treatment. Copyright © 2015, American Journal of Physiology - Renal Physiology.

Methodologic ramifications of paying attention to sex and gender differences in clinical research.

PubMed

Prins, Martin H; Smits, Kim M; Smits, Luc J

2007-01-01

Methodologic standards for studies on sex and gender differences should be developed to improve reporting of studies and facilitate their inclusion in systematic reviews. The essence of these studies lies within the concept of effect modification. This article reviews important methodologic issues in the design and reporting of pharmacogenetic studies. Differences in effect based on sex or gender should preferably be expressed in absolute terms (risk differences) to facilitate clinical decisions on treatment. Information on the distribution of potential effect modifiers or prognostic factors should be available to prevent a biased comparison of differences in effect between genotypes. Other considerations included the possibility of selective nonavailability of biomaterial and the choice of a statistical model to study effect modification. To ensure high study quality, additional methodologic issues should be taken into account when designing and reporting studies on sex and gender differences.

The gist and details of sex differences in cognition and the brain: How parallels in sex differences across domains are shaped by the locus coeruleus and catecholamine systems.

PubMed

Ycaza Herrera, Alexandra; Wang, Jiaxi; Mather, Mara

2018-05-19

Across three different domains, there are similar sex differences in how men and women process information. There tends to be a male advantage in attending to and remembering the gist (essential central information of a scene or situation), but a female advantage in attending to and remembering the details (non-essential peripheral information of a scene or situation). This is seen in emotional memory, where emotion enhances gist memory more for males than for females, but enhances detail memory more for females than for males. It also occurs in spatial memory, where men tend to notice and remember the gist of where they or objects are in space, allowing them to more flexibly manipulate themselves or objects within that space, whereas women tend to recall the details of the space around them, allowing them to accurately remember the locations of objects. Finally, such sex differences have also been noted in perception of stimuli such that men attend to global aspects of stimuli (such as a large letter E) more than women, whereas women attend more to the local aspects (such as the many smaller letter Ts making up the E). We review the parallel sex differences seen across these domains in this paper and how they relate to the different brain systems involved in each of these task domains. In addition, we discuss how sex differences in evolutionary pressures and in the locus coeruleus and norepinephrine system may account for why parallel sex differences occur across these different task domains. Copyright © 2018 Elsevier Ltd. All rights reserved.

Confidence mediates the sex difference in mental rotation performance.

PubMed

Estes, Zachary; Felker, Sydney

2012-06-01

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.

Sex differences associated with intermittent swim stress.

PubMed

Warner, Timothy A; Libman, Matthew K; Wooten, Katherine L; Drugan, Robert C

2013-11-01

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.

Sexing the brain: the science and pseudoscience of sex differences.

PubMed

Rogers, Lesley J

2010-06-01

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 of the functions of

Sex differences in depression during pregnancy and the postpartum period.

PubMed

Sundström Poromaa, Inger; Comasco, Erika; Georgakis, Marios K; Skalkidou, Alkistis

2017-01-02

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.

Sex differences in antiplatelet response in ischemic stroke.

PubMed

Meyer, Dawn M; Eastwood, Jo-Ann; Compton, Margaret P; Gylys, Karen; Zivin, Justin A; Ovbiagele, Bruce

2011-07-01

Sex differences exist in the occurrence, treatment and outcome of ischemic stroke. Compared with men, women have more stroke events and are less likely to fully recover from a stroke. Given the rapidly aging population, stroke incidence and mortality among women are projected to substantially rise by 2050. This has important public health consequences. Mitigating the burden of stroke among women will require a fundamental understanding of sex differences and sex-specific issues including cerebrovascular disease pathophysiology, treatment and outcome. An aspect of stroke treatment receiving increasing but insufficient attention involves possible interactions between estrogen levels, antiplatelet drugs and stroke outcome. Emerging evidence suggests that antiplatelet therapy may provide primary stroke protection but not primary myocardial infarction prevention in women, while the opposite may be true among men. Understanding sex-specific issues related to women who experience stroke is critical to clinicians who treat women with antiplatelet medications as part of a secondary stroke prevention regimen; however, the ideal antiplatelet medication, and dose, in women requires further research. In this article we present a conceptual framework for sex differences in antiplatelet treatment response in ischemic stroke, thrombus formation and the mediating role of estrogen, sex differences in antiplatelet treatment response in clinical trials, and sex differences in antiplatelet treatment use in ischemic stroke.

Sex differences in antiplatelet response in ischemic stroke

PubMed Central

Meyer, Dawn M; Eastwood, Jo-Ann; Compton, Margaret P; Gylys, Karen; Zivin, Justin A; Ovbiagele, Bruce

2011-01-01

Sex differences exist in the occurrence, treatment and outcome of ischemic stroke. Compared with men, women have more stroke events and are less likely to fully recover from a stroke. Given the rapidly aging population, stroke incidence and mortality among women are projected to substantially rise by 2050. This has important public health consequences. Mitigating the burden of stroke among women will require a fundamental understanding of sex differences and sex-specific issues including cerebrovascular disease pathophysiology, treatment and outcome. An aspect of stroke treatment receiving increasing but insufficient attention involves possible interactions between estrogen levels, antiplatelet drugs and stroke outcome. Emerging evidence suggests that antiplatelet therapy may provide primary stroke protection but not primary myocardial infarction prevention in women, while the opposite may be true among men. Understanding sex-specific issues related to women who experience stroke is critical to clinicians who treat women with antiplatelet medications as part of a secondary stroke prevention regimen; however, the ideal antiplatelet medication, and dose, in women requires further research. In this article we present a conceptual framework for sex differences in antiplatelet treatment response in ischemic stroke, thrombus formation and the mediating role of estrogen, sex differences in antiplatelet treatment response in clinical trials, and sex differences in antiplatelet treatment use in ischemic stroke. PMID:21790339

Gender and sex differences in job status and hypertension

PubMed Central

Clougherty, Jane E.; Eisen, Ellen A.; Slade, Martin D.; Kawachi, Ichiro; Cullen, Mark R.

2013-01-01

Objectives Studies have shown greater health risks associated with blue-collar manufacturing employment for women than men. It remains challenging, however, to distinguish cultural gendered factors influencing employment decisions (e.g., expected work roles, family responsibilities) from sex-linked biological differences shaping physiological response to workplace physical hazards. Methods We examined effects of hourly (blue-collar) status on incident hypertension among men and women, using health claims data for 14,618 white- and blue-collar aluminum manufacturing employees in eight U.S. 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 effects of hourly employment on hypertension risk, after adjusting for gender differences in job placement, we applied time-weighted logistic regression models, stratified by propensity score, with additional adjustment for socioeconomic confounders. Results Family structure (partnership, parity) influenced job status for both sexes; single mothers were more likely to hold hourly jobs (OR = 2.02 (95% CI = 1.37–2.97)), partnered men with children less likely (OR = 0.68 (0.56–0.83)). Education, age at hire, and race influenced job placement for both sexes. The effect of hourly status on hypertension was significant only among women predicted to be hourly (OR = 1.78 (1.34 – 2.35)). Conclusions Our results indicate significant risks of hypertension associated with hourly status for women, possibly exacerbated by sociodemographic factors predicting hourly status (e.g., single parenthood, low education). Greater attention to gender differences in job status, workplace stressors, and health risks associated with hourly work, is warranted. PMID:20864467

Targeted metabolomic profiling in rat tissues reveals sex differences.

PubMed

Ruoppolo, Margherita; Caterino, Marianna; Albano, Lucia; Pecce, Rita; Di Girolamo, Maria Grazia; Crisci, Daniela; Costanzo, Michele; Milella, Luigi; Franconi, Flavia; Campesi, Ilaria

2018-03-16

Sex differences affect several diseases and are organ-and parameter-specific. In humans and animals, sex differences also influence the metabolism and homeostasis of amino acids and fatty acids, which are linked to the onset of diseases. Thus, the use of targeted metabolite profiles in tissues represents a powerful approach to examine the intermediary metabolism and evidence for any sex differences. To clarify the sex-specific activities of liver, heart and kidney tissues, we used targeted metabolomics, linear discriminant analysis (LDA), principal component analysis (PCA), cluster analysis and linear correlation models to evaluate sex and organ-specific differences in amino acids, free carnitine and acylcarnitine levels in male and female Sprague-Dawley rats. Several intra-sex differences affect tissues, indicating that metabolite profiles in rat hearts, livers and kidneys are organ-dependent. Amino acids and carnitine levels in rat hearts, livers and kidneys are affected by sex: male and female hearts show the greatest sexual dimorphism, both qualitatively and quantitatively. Finally, multivariate analysis confirmed the influence of sex on the metabolomics profiling. Our data demonstrate that the metabolomics approach together with a multivariate approach can capture the dynamics of physiological and pathological states, which are essential for explaining the basis of the sex differences observed in physiological and pathological conditions.

A Population-Based Comparison of Female and Male Same-Sex Parent and Different-Sex Parent Households.

PubMed

Bos, Henny M W; Kuyper, Lisette; Gartrell, Nanette K

2018-03-01

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.

The new science of cognitive sex differences.

PubMed

Miller, David I; Halpern, Diane F

2014-01-01

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.

Sex Differences in Cognitive Abilities. Third Edition.

ERIC Educational Resources Information Center

Halpern, Diane F.

This book examines the science and politics of cognitive sex differences, reflecting theories and research in the area over the past several years. Eight chapters discuss: (1) "Introduction and Overview" (e.g., theoretical approaches, values and science, and terminology); (2) "Searching for Sex Differences in Cognitive…

Sex and gender differences in pain and analgesia.

PubMed

Mogil, Jeffrey S; Bailey, Andrea L

2010-01-01

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.

Sex differences in impulsive action and impulsive choice.

PubMed

Weafer, Jessica; de Wit, Harriet

2014-11-01

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.

Sex differences in impulsive action and impulsive choice

PubMed Central

Weafer, Jessica; de Wit, Harriet

2013-01-01

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. PMID:24286704

Sex and Gender Differences in Myocarditis and Dilated Cardiomyopathy

PubMed Central

Fairweather, DeLisa; Cooper, Leslie T; Blauwet, Lori A

2014-01-01

Heart failure due to nonischemic dilated cardiomyopathy (DCM) contributes significantly to the global burden of cardiovascular disease. Myocarditis is in turn a major cause of acute dilated cardiomyopathy in both men and women. However, recent clinical and experimental evidence suggests that the pathogenesis and prognosis of DCM differ between the sexes. This seminar provides a contemporary perspective on the immune mediators of myocarditis, including interdependent elements of the innate and adaptive immune response. The heart's acute response to injury is influenced by sex hormones that appear to determine the subsequent risk of chronic DCM. Preliminary data suggest additional genetic variations may account for some of the differences in epidemiology, left ventricular recovery and survival between men and women. We highlight the gaps in our knowledge regarding the management of women with acute DCM and discuss emerging therapies, including bromocriptine for the treatment of peripartum cardiomyopathy. PMID:23158412

The evolution of sex ratio differences and inflorescence architectures in Begonia (Begoniaceae).

PubMed

Twyford, Alex D; Ennos, Richard A; White, Chris D; Ali, Mobina Shaukat; Kidner, Catherine A

2014-02-01

A major benefit conferred by monoecy is the ability to alter floral sex ratio in response to selection. In monoecious species that produce flowers of a given sex at set positions on the inflorescence, floral sex ratio may be related to inflorescence architecture. We studied the loci underlying differences in inflorescence architecture between two monoecious Begonia species and related this to floral sex ratios. We performed trait comparisons and quantitative trait locus (QTL) mapping in a segregating backcross population between Central American Begonia plebeja and B. conchifolia. We focused on traits related to inflorescence architecture, sex ratios, and other reproductive traits. The inflorescence branching pattern of B. conchifolia was more asymmetric than B. plebeja, which in turn affects the floral sex ratio. Colocalizing QTLs of moderate effect influenced both the number of male flowers and the fate decisions of axillary meristems, demonstrating the close link between inflorescence architecture and sex ratio. Additional QTLs were found for stamen number (30% variance explained, VE) and pollen sterility (12.3% VE). One way in which Begonia species develop different floral sex ratios is through modifications of their inflorescence architecture. The potential pleiotropic action of QTL on inflorescence branching and floral sex ratios may have major implications for trait evolution and responses to selection. The presence of a single QTL of large effect on stamen number may allow rapid divergence for this key floral trait. We propose candidate loci for stamen number and inflorescence branching for future characterization.

Sex Differences in Reading: A Biological Explanation.

ERIC Educational Resources Information Center

Aliotti, Nicholas C.

Although sex differences in reading and related language functions have frequently been reported for both average and retarded readers, the explanations thus far proposed (maturation rate, sex-role development, textbook content, "female bias," and psycho-social factors) do not satisfactorily account for these differences. One hypothesis that might…

The Genetics of Sex Differences in Brain and Behavior

PubMed Central

Ngun, Tuck C; Ghahramani, Negar; Sánchez, Francisco J.; Bocklandt, Sven; Vilain, Eric

2010-01-01

Biological differences between men and women contribute to many sex-specific illnesses and disorders. Historically, it was argued that such differences were largely, if not exclusively, due to gonadal hormone secretions. However, emerging research has shown that some differences are mediated by mechanisms other than the action of these hormone secretions and in particular by products of genes located on the X and Y chromosomes, which we refer to as direct genetic effects. This paper reviews the evidence for direct genetic effects in behavioral and brain sex differences. We highlight the `four core genotypes' model and sex differences in the midbrain dopaminergic system, specifically focusing on the role of Sry. We also discuss novel research being done on unique populations including people attracted to the same sex and people with a cross-gender identity. As science continues to advance our understanding of biological sex differences, a new field is emerging that is aimed at better addressing the needs of both sexes: gender-based biology and medicine. Ultimately, the study of the biological basis for sex differences will improve healthcare for both men and women. PMID:20951723

Sex differences in Hadza eating frequency by food type.

PubMed

Berbesque, J Colette; Marlowe, Frank W; Crittenden, Alyssa N

2011-01-01

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.

Sex differences in circadian food anticipatory activity are not altered by individual manipulations of sex hormones or sex chromosome copy number in mice

PubMed Central

Huddy, Timothy F.; Ogawa-Okada, Maya; Adkins, Jamie L.

2018-01-01

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. PMID:29385171

Sex differences in circadian food anticipatory activity are not altered by individual manipulations of sex hormones or sex chromosome copy number in mice.

PubMed

Aguayo, Antonio; Martin, Camille S; Huddy, Timothy F; Ogawa-Okada, Maya; Adkins, Jamie L; Steele, Andrew D

2018-01-01

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.

Understanding the Broad Influence of Sex Hormones and Sex Differences in the Brain

PubMed Central

McEwen, Bruce S.; Milner, Teresa A.

2016-01-01

Sex hormones act throughout the entire brain of both males and females via both genomic and non-genomic 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, post-synaptic 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 upon gene expression induce spine synapses, up- or down-regulate and alter the distribution of neurotransmitter receptors, 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, and upon functions not previously regarded as subject to such differences, indicates that we are entering a new era of our ability to understand and appreciate the diversity of gender-related behaviors and brain functions. PMID:27870427

Sex Roles and Gender Differences in the Experience of Depression.

ERIC Educational Resources Information Center

Chevron, Eve S.; And Others

1978-01-01

Sex differences and sex role correlates of depressive experiences were studied in 87 female and 41 male college students. The sex differences and intrasex correlations found indicate that experiences of depression are associated with different facets of sex role stereotypes. (Author)

Sex differences in vascular endothelial function and health in humans: impacts of exercise.

PubMed

Green, Daniel J; Hopkins, Nicola D; Jones, Helen; Thijssen, Dick H J; Eijsvogels, Thijs M H; Yeap, Bu B

2016-02-01

What is the topic of this review? This brief review discusses potential sex differences in arterial function across the age span, with special emphasis on the effects of oestrogen and testosterone on the vascular endothelium. What advances does it highlight? We discuss the relationship between the impacts of sex hormones on arterial function and health in the context of epidemiological evidence pertaining to the menopause and ageing. Studies performed in humans are emphasized, alongside insights from animal studies. Findings suggest that the combination of exercise and hormone administration should be potentially synergistic or additive in humans. This brief review presents historical evidence for the purported impacts of male and female sex hormones on the vasculature in humans, including effects on macro- and microvascular function and health. Impacts of ageing on hormonal changes and arterial function are considered in the context of the menopause. Physiological data are presented alongside clinical outcomes from large trials, in an attempt to rationalize disparate findings along the bench-to-bedside continuum. Finally, the theoretical likelihood that exercise and hormone treatment may induce synergistic and/or additive vascular adaptations is developed in the context of recent laboratory studies that have compared male and female responses to training. Differences between men and women in terms of the impact of age and cardiorespiratory fitness on endothelial function are addressed. Ultimately, this review highlights the paucity of high-quality and compelling evidence regarding the fundamental impact, in humans, of sex differences on arterial function and the moderating impacts of exercise on arterial function, adaptation and health at different ages in either sex. © 2015 The Authors. Experimental Physiology © 2015 The Physiological Society.

Sex differences in processing printed advertisements.

PubMed

Putrevu, Sanjay

2004-06-01

The success of using biological sex to divide or segment markets requires a thorough understanding of how men and women process and respond to advertisements and other persuasive communications. Toward this end, this research (N=64; 32 men and 32 women) studied how college-age men and women respond to printed advertisements. There were no differences between the sexes in recall and recognition of claims in advertisements, but men and women generated different types of message relevant thoughts-women generated more category thoughts and men generated more attribute thoughts, suggesting that, while women and men might not differ in the depth of processing, they might use different processing styles.

Sex Differences in Stress-Related Psychiatric Disorders: Neurobiological Perspectives

PubMed Central

Bangasser, Debra A.; Valentino, Rita J.

2014-01-01

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. PMID:24726661

The effect of parasites on sex differences in selection.

PubMed

Sharp, N P; Vincent, C M

2015-04-01

The life history strategies of males and females are often divergent, creating the potential for sex differences in selection. Deleterious mutations may be subject to stronger selection in males, owing to sexual selection, which can improve the mean fitness of females and reduce mutation load in sexual populations. However, sex differences in selection might also maintain sexually antagonistic genetic variation, creating a sexual conflict load. The overall impact of separate sexes on fitness is unclear, but the net effect is likely to be positive when there is a large sex difference in selection against deleterious mutations. Parasites can also have sex-specific effects on fitness, and there is evidence that parasites can intensify the fitness consequences of deleterious mutations. Using lines that accumulated mutations for over 60 generations, we studied the effect of the pathogenic bacterium Pseudomonas aeruginosa on sex differences in selection in the fruit fly Drosophila melanogaster. Pseudomonas infection increased the sex difference in selection, but may also have weakened the intersexual correlation for fitness. Our results suggest that parasites may increase the benefits of sexual selection.

Sex Differences in Gray Matter Volume of the Right Anterior Hippocampus Explain Sex Differences in Three-Dimensional Mental Rotation

PubMed Central

Wei, Wei; Chen, Chuansheng; Dong, Qi; Zhou, Xinlin

2016-01-01

Behavioral studies have reported that males perform better than females in 3-dimensional (3D) mental rotation. Given the important role of the hippocampus in spatial processing, the present study investigated whether structural differences in the hippocampus could explain the sex difference in 3D mental rotation. Results showed that after controlling for brain size, males had a larger anterior hippocampus, whereas females had a larger posterior hippocampus. Gray matter volume (GMV) of the right anterior hippocampus was significantly correlated with 3D mental rotation score. After controlling GMV of the right anterior hippocampus, sex difference in 3D mental rotation was no longer significant. These results suggest that the structural difference between males’ and females’ right anterior hippocampus was a neurobiological substrate for the sex difference in 3D mental rotation. PMID:27895570

Sex differences in visuospatial abilities persist during induced hypogonadism

PubMed Central

Guerrieri, Gioia M.; Wakim, Paul G.; Keenan, P.A.; Schenkel, Linda A; Berlin, Kate; Gibson, Carolyn J.; Rubinow, David R.; Schmidt, Peter J.

2016-01-01

Background 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. Objective To evaluate cognitive performance in healthy eugonadal men and women before and again during GnRH agonist-induced hypogonadism. Methods 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 68 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. Results 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). Conclusion 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

Sex differences in visuospatial abilities persist during induced hypogonadism.

PubMed

Guerrieri, Gioia M; Wakim, Paul G; Keenan, P A; Schenkel, Linda A; Berlin, Kate; Gibson, Carolyn J; Rubinow, David R; Schmidt, Peter J

2016-01-29

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

Sex Differences in Cognitive Abilities. Fourth Edition

ERIC Educational Resources Information Center

Halpern, Diane F.

2011-01-01

The fourth edition of "Sex Differences in Cognitive Abilities" critically examines the breadth of research on this complex and controversial topic, with the principal aim of helping the reader to understand where sex differences are found--and where they are not. Since the publication of the third edition, there have been many exciting and…

Sex differences in the pharmacokinetics of antidepressants: influence of female sex hormones and oral contraceptives.

PubMed

Damoiseaux, Valérie A; Proost, Johannes H; Jiawan, Vincent C R; Melgert, Barbro N

2014-06-01

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 differences. These differences can partially be explained by differences in pharmacokinetic properties (i.e., absorption, distribution, metabolism, and excretion) of drugs in males and females. More recent research has shown that sex hormones may influence all these previously named pharmacokinetic processes. As concentrations of sex hormones vary throughout the female lifespan, these hormonal variations can have effects on therapeutic responses to antidepressants as well as the occurrence of adverse events. The purpose of this paper is therefore to review the literature reporting on the effects of female sex hormones on the pharmacokinetics of antidepressants and to discuss and evaluate the implications of changes in levels of sex hormones throughout life for the treatment of depression.

Sex Differences in Cognitive Impairment and Alzheimer’s Disease

PubMed Central

Li, Rena; Singh, Meharvan

2014-01-01

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. PMID:24434111

Sex differences in stress-related psychiatric disorders: neurobiological perspectives.

PubMed

Bangasser, Debra A; Valentino, Rita J

2014-08-01

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.

Understanding the broad influence of sex hormones and sex differences in the brain.

PubMed

McEwen, Bruce S; Milner, Teresa A

2017-01-02

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.

Sex differences in impulsivity: a meta-analysis.

PubMed

Cross, Catharine P; Copping, Lee T; Campbell, Anne

2011-01-01

Men are overrepresented in socially problematic behaviors, such as aggression and criminal behavior, which have been linked to impulsivity. Our review of impulsivity is organized around the tripartite theoretical distinction between reward hypersensitivity, punishment hyposensitivity, and inadequate effortful control. Drawing on evolutionary, criminological, developmental, and personality theories, we predicted that sex differences would be most pronounced in risky activities with men demonstrating greater sensation seeking, greater reward sensitivity, and lower punishment sensitivity. We predicted a small female advantage in effortful control. We analyzed 741 effect sizes from 277 studies, including psychometric and behavioral measures. Women were consistently more punishment sensitive (d = -0.33), but men did not show greater reward sensitivity (d = 0.01). Men showed significantly higher sensation seeking on questionnaire measures (d = 0.41) and on a behavioral risk-taking task (d = 0.36). Questionnaire measures of deficits in effortful control showed a very modest effect size in the male direction (d = 0.08). Sex differences were not found on delay discounting or executive function tasks. The results indicate a stronger sex difference in motivational rather than effortful or executive forms of behavior control. Specifically, they support evolutionary and biological theories of risk taking predicated on sex differences in punishment sensitivity. A clearer understanding of sex differences in impulsivity depends upon recognizing important distinctions between sensation seeking and impulsivity, between executive and effortful forms of control, and between impulsivity as a deficit and as a trait.

Sex and gender differences in substance use disorders.

PubMed

McHugh, R Kathryn; Votaw, Victoria R; Sugarman, Dawn E; Greenfield, Shelly F

2017-11-10

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.

Sex Differences in Influenceability

ERIC Educational Resources Information Center

Eagly, Alice H.

1978-01-01

Examines the hypothesis that women are more easily influenced than men by reviewing the literature on persuasion and conformity research. Persuasion research and conformity studies not involving group pressure show scant empirical support for sex differences. For group pressure conformity research, a substantial minority of studies support the…

Sex Differences in Pharmacokinetics and Pharmacodynamics

PubMed Central

Soldin, OP; Mattison, DR

2013-01-01

Males and females differ in their response to drug treatment. These differences can be critical in response to drug treatment. It is therefore essential to understand those differences to appropriately conduct risk assessment and to design safe and effective treatments. Even from that modest perspective, how and when we use drugs can result in unwanted and unexpected outcomes. We summarize the sex differences that impact pharmacokinetics and pharmacodynamics and include a general comparison of clinical pharmacology as it applies to men, pregnant and non-pregnant women. Since this is an area rapidly evolving, it is essential for the practitioner to review drug prescribing information and recent literature to understand fully the impact of sex differences in clinical therapeutics. PMID:19385708

Sex differences in fear discrimination do not manifest as differences in conditioned inhibition.

PubMed

Foilb, Allison R; Bals, Julia; Sarlitto, Mary C; Christianson, John P

2018-01-01

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 if this sex difference transferred to fear inhibition, rats were tested for conditioned inhibition in a summation test with the CS+ and CS- presented in compound; no sex difference emerged. The results suggest sex differences in the neural mechanisms of discrimination learning but not recall of a fear inhibitor. © 2018 Foilb et al.; Published by Cold Spring Harbor Laboratory Press.

Sex differences in addictive disorders.

PubMed

Fattore, Liana; Melis, Miriam; Fadda, Paola; Fratta, Walter

2014-08-01

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.

Sex Differences in Drug Disposition

PubMed Central

Soldin, Offie P.; Chung, Sarah H.; Mattison, Donald R.

2011-01-01

Physiological, hormonal, and genetic differences between males and females affect the prevalence, incidence, and severity of diseases and responses to therapy. Understanding these differences is important for designing safe and effective treatments. This paper summarizes sex differences that impact drug disposition and includes a general comparison of clinical pharmacology as it applies to men and women. PMID:21403873

Sex Differences in Magical Ideation: A Community-Based Twin Study

PubMed Central

Karcher, Nicole R.; Slutske, Wendy S.; Kerns, John G.; Piasecki, Thomas M.; Martin, Nicholas G.

2014-01-01

Two questions regarding sex differences in magical ideation were investigated in this study: (1) whether there are mean level sex differences on the Magical Ideation Scale (MIS), and (2) whether there are quantitative and/or qualitative sex differences in the genetic contributions to variation on this scale. These questions were evaluated using data obtained from a large community sample of adult Australian twins (N=4,355) that included opposite-sex pairs. Participants completed a modified 15-item version of the MIS within a larger assessment battery. Women reported both higher means and variability on the MIS than men; this was also observed within families (in opposite-sex twin pairs). Biometric modeling indicated that the proportion of variation in MIS scores due to genetic influences (indicating quantitative sex differences) and the specific latent genetic contributions to this variation (indicating qualitative sex differences) were the same in men and women. These findings clarify the nature of sex differences in magical ideation and point to avenues for future research. PMID:24364500

A reproductive threat-based model of evolved sex differences in jealousy.

PubMed

Sagarin, Brad J; Becker, D Vaughn; Guadagno, Rosanna E; Wilkinson, Wayne W; Nicastle, Lionel D

2012-08-10

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.

Negligible Sex Differences in General Intelligence.

ERIC Educational Resources Information Center

Colom, Roberto; Juan-Espinosa, Manuel; Abad, Francisco; Garcia, Luis F.

2000-01-01

Studied sex differences in general intelligence in 10,475 adults taking cognitive test batteries. Results suggest a negligible difference in general intelligence, a finding consistent with findings from quite different test batteries and subject samples. (SLD)

Changes in Family Roles, Socialization, and Sex Differences

ERIC Educational Resources Information Center

Hoffman, Lois Wladis

1977-01-01

The research literature supporting the thesis that as awareness of social changes increases, the sex-linked differences in socialization will diminish with the corresponding result being that sex differences in behavior will also diminish, is examined in this paper. (Author/AM)

Sex differences in patterns of genital sexual arousal: measurement artifacts or true phenomena?

PubMed

Suschinsky, Kelly D; Lalumière, Martin L; Chivers, Meredith L

2009-08-01

Sex differences in patterns of sexual arousal have been reported recently. Men's genital arousal is typically more category-specific than women's, such that men experience their greatest genital arousal to stimuli depicting their preferred sex partners whereas women experience significant genital arousal to stimuli depicting both their preferred and non-preferred sex partners. In addition, men's genital and subjective sexual arousal patterns are more concordant than women's: The correlation between genital and subjective sexual arousal is much larger in men than in women. These sex differences could be due to low response-specificity in the measurement of genital arousal in women. The most commonly used measure of female sexual arousal, vaginal photoplethysmography, has not been fully validated and may not measure sexual arousal specifically. A total of 20 men and 20 women were presented with various sexual and non-sexual emotionally laden short film clips while their genital and subjective sexual arousal were measured. Results suggest that vaginal photoplethysmography is a measure of sexual arousal exclusively. Women's genital responses were highest during sexual stimuli and absent during all non-sexual stimuli. Sex differences in degree of category-specificity and concordance were replicated: Men's genital responses were more category-specific than women's and men's genital and subjective sexual arousal were more strongly correlated than women's. The results from the current study support the continued use of vaginal photoplethysmography in investigating sex differences in patterns of sexual arousal.

Sex Differences in Animal Models: Focus on Addiction

PubMed Central

Becker, Jill B.

2016-01-01

The purpose of this review is to discuss ways to think about and study sex differences in preclinical animal models. We use the framework of addiction, in which animal models have excellent face and construct validity, to illustrate the importance of considering sex differences. There are four types of sex differences: qualitative, quantitative, population, and mechanistic. A better understanding of the ways males and females can differ will help scientists design experiments to characterize better the presence or absence of sex differences in new phenomena that they are investigating. We have outlined major quantitative, population, and mechanistic sex differences in the addiction domain using a heuristic framework of the three established stages of the addiction cycle: binge/intoxication, withdrawal/negative affect, and preoccupation/anticipation. Female rats, in general, acquire the self-administration of drugs and alcohol more rapidly, escalate their drug taking with extended access more rapidly, show more motivational withdrawal, and (where tested in animal models of “craving”) show greater reinstatement. The one exception is that female rats show less motivational withdrawal to alcohol. The bases for these quantitative sex differences appear to be both organizational, in that estradiol-treated neonatal animals show the male phenotype, and activational, in that the female phenotype depends on the effects of gonadal hormones. In animals, differences within the estrous cycle can be observed but are relatively minor. Such hormonal effects seem to be most prevalent during the acquisition of drug taking and less influential once compulsive drug taking is established and are linked largely to progesterone and estradiol. This review emphasizes not only significant differences in the phenotypes of females and males in the domain of addiction but emphasizes the paucity of data to date in our understanding of those differences. PMID:26772794

Sex- and Gender-Differences in Emotion: A Preliminary Examination.

ERIC Educational Resources Information Center

Emmers, Tara M.

This paper offers a preliminary examination of literature reviewing sex and gender differences in the five prototypic emotions of fear, anger, sadness, joy, and love. The paper notes that within the literature on sex and gender differences, the terms "sex" and "gender" are often erroneously referred to interchangeably…

Sex differences in animal models of psychiatric disorders

PubMed Central

Kokras, N; Dalla, C

2014-01-01

Psychiatric disorders are characterized by sex differences in their prevalence, symptomatology and treatment response. Animal models have been widely employed for the investigation of the neurobiology of such disorders and the discovery of new treatments. However, mostly male animals have been used in preclinical pharmacological studies. In this review, we highlight the need for the inclusion of both male and female animals in experimental studies aiming at gender-oriented prevention, diagnosis and treatment of psychiatric disorders. We present behavioural findings on sex differences from animal models of depression, anxiety, post-traumatic stress disorder, substance-related disorders, obsessive–compulsive disorder, schizophrenia, bipolar disorder and autism. Moreover, when available, we include studies conducted across different stages of the oestrous cycle. By inspection of the relevant literature, it is obvious that robust sex differences exist in models of all psychiatric disorders. However, many times results are conflicting, and no clear conclusion regarding the direction of sex differences and the effect of the oestrous cycle is drawn. Moreover, there is a lack of considerable amount of studies using psychiatric drugs in both male and female animals, in order to evaluate the differential response between the two sexes. Notably, while in most cases animal models successfully mimic drug response in both sexes, test parameters and treatment-sensitive behavioural indices are not always the same for male and female rodents. Thus, there is an increasing need to validate animal models for both sexes and use standard procedures across different laboratories. Linked Articles This article is part of a themed section on Animal Models in Psychiatry Research. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2014.171.issue-20 PMID:24697577

Sex Differences in the Presentation of Chronic Low Back Pain

ERIC Educational Resources Information Center

Sheffer, Christine E.; Cassisi, Jeffrey E.; Ferraresi, Laurette M.; Lofland, Kenneth R.; McCracken, Lance M.

2002-01-01

Sex differences in 351 patients with chronic low back pain were examined. Biological, psychological, and psychosocial factors were considered. Sex differences in adaptive functioning were consistent with traditional gender roles. Significant interactions were found for sex and employment status, and sex and marital status. Retired women reported…

The effect of sex on the repeatability of evolution in different environments.

PubMed

Lachapelle, Josianne; Colegrave, Nick

2017-04-01

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.

A Systems Biology Approach to Investigating Sex Differences in Cardiac Hypertrophy.

PubMed

Harrington, Josephine; Fillmore, Natasha; Gao, Shouguo; Yang, Yanqin; Zhang, Xue; Liu, Poching; Stoehr, Andrea; Chen, Ye; Springer, Danielle; Zhu, Jun; Wang, Xujing; Murphy, Elizabeth

2017-08-19

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.

Homage to Bateman: sex roles predict sex differences in sexual selection.

PubMed

Fritzsche, Karoline; Arnqvis, Göran

2013-07-01

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.

Sex Differences in Language First Appear in Gesture

ERIC Educational Resources Information Center

Ozcaliskan, Seyda; Goldin-Meadow, Susan

2010-01-01

Children differ in how quickly they reach linguistic milestones. Boys typically produce their first multi-word sentences later than girls do. We ask here whether there are sex differences in children's gestures that precede, and presage, these sex differences in speech. To explore this question, we observed 22 girls and 18 boys every 4 months as…

Sex and Gender Differences in Risk, Pathophysiology and Complications of Type 2 Diabetes Mellitus.

PubMed

Kautzky-Willer, Alexandra; Harreiter, Jürgen; Pacini, Giovanni

2016-06-01

The steep rise of type 2 diabetes mellitus (T2DM) and associated complications go along with mounting evidence of clinically important sex and gender differences. T2DM is more frequently diagnosed at lower age and body mass index in men; however, the most prominent risk factor, which is obesity, is more common in women. Generally, large sex-ratio differences across countries are observed. Diversities in biology, culture, lifestyle, environment, and socioeconomic status impact differences between males and females in predisposition, development, and clinical presentation. Genetic effects and epigenetic mechanisms, nutritional factors and sedentary lifestyle affect risk and complications differently in both sexes. Furthermore, sex hormones have a great impact on energy metabolism, body composition, vascular function, and inflammatory responses. Thus, endocrine imbalances relate to unfavorable cardiometabolic traits, observable in women with androgen excess or men with hypogonadism. Both biological and psychosocial factors are responsible for sex and gender differences in diabetes risk and outcome. Overall, psychosocial stress appears to have greater impact on women rather than on men. In addition, women have greater increases of cardiovascular risk, myocardial infarction, and stroke mortality than men, compared with nondiabetic subjects. However, when dialysis therapy is initiated, mortality is comparable in both males and females. Diabetes appears to attenuate the protective effect of the female sex in the development of cardiac diseases and nephropathy. Endocrine and behavioral factors are involved in gender inequalities and affect the outcome. More research regarding sex-dimorphic pathophysiological mechanisms of T2DM and its complications could contribute to more personalized diabetes care in the future and would thus promote more awareness in terms of sex- and gender-specific risk factors.

Sex and Gender Differences in Risk, Pathophysiology and Complications of Type 2 Diabetes Mellitus

PubMed Central

Harreiter, Jürgen; Pacini, Giovanni

2016-01-01

The steep rise of type 2 diabetes mellitus (T2DM) and associated complications go along with mounting evidence of clinically important sex and gender differences. T2DM is more frequently diagnosed at lower age and body mass index in men; however, the most prominent risk factor, which is obesity, is more common in women. Generally, large sex-ratio differences across countries are observed. Diversities in biology, culture, lifestyle, environment, and socioeconomic status impact differences between males and females in predisposition, development, and clinical presentation. Genetic effects and epigenetic mechanisms, nutritional factors and sedentary lifestyle affect risk and complications differently in both sexes. Furthermore, sex hormones have a great impact on energy metabolism, body composition, vascular function, and inflammatory responses. Thus, endocrine imbalances relate to unfavorable cardiometabolic traits, observable in women with androgen excess or men with hypogonadism. Both biological and psychosocial factors are responsible for sex and gender differences in diabetes risk and outcome. Overall, psychosocial stress appears to have greater impact on women rather than on men. In addition, women have greater increases of cardiovascular risk, myocardial infarction, and stroke mortality than men, compared with nondiabetic subjects. However, when dialysis therapy is initiated, mortality is comparable in both males and females. Diabetes appears to attenuate the protective effect of the female sex in the development of cardiac diseases and nephropathy. Endocrine and behavioral factors are involved in gender inequalities and affect the outcome. More research regarding sex-dimorphic pathophysiological mechanisms of T2DM and its complications could contribute to more personalized diabetes care in the future and would thus promote more awareness in terms of sex- and gender-specific risk factors. PMID:27159875

Spatial task performance, sex differences, and motion sickness susceptibility.

PubMed

Levine, Max E; Stern, Robert M

2002-10-01

There are substantial individual differences in susceptibility to motion sickness, yet little is known about what mediates these differences. Spatial ability and sex have been suggested as possible factors in this relationship. 89 participants (57 women) were administered a Motion Sickness Questionnaire that assesses motion sickness susceptibility, a Water-level Task that gauges sensitivity to gravitational upright, and a Mental Rotation Task that tests an individual's awareness of how objects typically move in space. Significant sex differences were observed in performance of both the Water-level Task (p<.01), and the Mental Rotation Task (p<.005), with women performing less accurately than men. Women also had significantly higher scores on the Motion Sickness Questionnaire (p<.005). Among men, but not women, significant negative relationships were observed between Water-level Task performance and Motion Sickness Questionnaire score (p<.001) and between Mental Rotation Task performance and Motion Sickness Questionnaire score (p<.005). In conclusion, women performed significantly more poorly than men did on the spatial ability tasks and reported significantly more bouts of motion sickness. In addition, men showed a significant negative relationship between spatial ability and motion sickness susceptibility.

Sex differences in the physiology of eating

PubMed Central

Asarian, Lori

2013-01-01

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

Exploring mechanisms underlying sex-specific differences in mortality of Lake Michigan bloaters

USGS Publications Warehouse

Bunnell, D.B.; Madenjian, C.P.; Rogers, M.W.; Holuszko, J.D.; Begnoche, L.J.

2012-01-01

Sex-specific differences in mortality rates have been observed among freshwater and marine fish taxa, and underlying mechanisms can include sex-specific differences in (1) age at maturity, (2) growth rate, or (3) activity or behavior during the spawning period. We used a long-term (1973–2009) Lake Michigan data set to evaluate whether there were sex-specific differences in catch per unit effort, mortality, age at maturity, and length at age in bloaters Coregonus hoyi. Because bloater population biomass varied 200-fold during the years analyzed, we divided the data into three periods: (1) 1973–1982 (low biomass), (2) 1983–1997 (high biomass), and (3) 1998–2009 (low biomass). Mortality was higher for males than for females in periods 2 and 3; the average instantaneous total mortality rate (Z) over these two periods was 0.71 for males and 0.57 for females. Length at age was slightly greater (2–6%) for females than for males in different age-classes (3–6 years) during each period. Age at maturity was earlier for males than for females in periods 1 and 2, but the mean difference was only 0.2–0.4 years. To test the hypothesis that somatic lipids declined more in males than in females during spawning (perhaps due to increased activity or reduced feeding), we estimated sex-specific percent somatic lipids for fish sampled in 2005–2006 and 2007–2008. During 2005–2006, somatic lipids declined from prespawning to postspawning for males but were unchanged for females. During 2007–2008, however, somatic lipids were unchanged for males, whereas they increased for females. We found that sex-specific differences in Z occurred in the Lake Michigan bloater population, but our hypotheses that sex-specific differences in maturity and growth could explain this pattern were generally unsupported. Our hypothesis that somatic lipids in males declined during spawning at a faster rate than in females will require additional research to clarify its importance.

Interactive effects of sex hormones and gender stereotypes on cognitive sex differences--a psychobiosocial approach.

PubMed

Hausmann, Markus; Schoofs, Daniela; Rosenthal, Harriet E S; Jordan, Kirsten

2009-04-01

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.

Sex differences in confidence influence patterns of conformity.

PubMed

Cross, Catharine P; Brown, Gillian R; Morgan, Thomas J H; Laland, Kevin N

2017-11-01

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.

Sex differences in jealousy: a contribution from attachment theory.

PubMed

Levy, Kenneth N; Kelly, Kristen M

2010-02-01

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 < .001. A series of sequential logistic regression analyses indicated significant moderation of the sex-jealousy relationship by attachment style. Implications of an attachment perspective are discussed.

Vasopressin and oxytocin receptor systems in the brain: sex differences and sex-specific regulation of social behavior

PubMed Central

Dumais, Kelly M.; Veenema, Alexa H.

2015-01-01

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

Vasopressin and oxytocin receptor systems in the brain: Sex differences and sex-specific regulation of social behavior.

PubMed

Dumais, Kelly M; Veenema, Alexa H

2016-01-01

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.

The Development of Sex-Related Differences in Achievement.

ERIC Educational Resources Information Center

Petersen, Anne C.

Although sex differences in research have received considerable attention, few researchers have examined the bias, social context, and process of that research. In analyzing sex differences in academic achievement over the past 10 years, three areas (mathematics, spatial ability, and verbal ability) would appear to establish consistent sex…

Comment on "The effect of same-sex marriage laws on different-sex marriage: evidence from the Netherlands".

PubMed

Dinno, Alexis

2014-12-01

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.

In the Pursuit of Sons: Additional Births or Sex-Selective Abortion in Pakistan?

PubMed Central

Zaidi, Batool; Morgan, S. Philip

2017-01-01

Even though Pakistan is a highly patriarchal society, it has not featured prominently in studies focusing on sex-selective abortion and sex ratios at birth. But with fertility declining and existing strong son preference—Pakistan has one of the highest desired sex ratios in the world—how will Pakistani families respond? In the pursuit of sons, will they have additional children or resort to sex-selective abortions? Or is there evidence that the pursuit of sons is weakening? Using data from three rounds of the demographic and health survey, we show clear evidence of son preference in fertility intentions, patterns of contraceptive use and parity progression ratios. More specifically, we find pervasive evidence that Pakistanis continue childbearing to have a son, to have more than one son and to have at least one daughter. We do not find consistent and convincing evidence that sex ratios at birth (which indicate sex-selective abortion) are increasing. PMID:28392607

Sex differences in mental rotation and how they add to the understanding of autism.

PubMed

Zapf, Alexandra C; Glindemann, Liv A; Vogeley, Kai; Falter, Christine M

2015-01-01

The most consistent cognitive sex differences have been found in the visuo-spatial domain, using Mental Rotation (MR) tasks. Such sex differences have been suggested to bear implications on our understanding of autism spectrum disorders (ASD). However, it is still debated how the sex difference in MR performance relates to differences between individuals with ASD compared to typically developed control persons (TD). To provide a detailed exploration of sex differences in MR performance, we studied rotational (indicated by slopes) and non-rotational aspects (indicated by intercepts) of the MR task in TD individuals (total N = 50). Second-to-fourth digit length ratios (2D:4D) were measured to investigate the associations between prenatal testosterone and performance on MR tasks. Handedness was assessed by the use of the Edinburgh Handedness Inventory in order to examine the relation between handedness and MR performance. In addition, we investigated the relation of spatial to systemising abilities, both of which have been associated with sex differences and with ASD, employing the Intuitive Physics Test (IPT). Results showed a male advantage in rotational aspects of the MR task, which correlated with IPT results. These findings are in contrast to the MR performance of individuals with ASD who have been shown to outperform TD persons in the non-rotational aspects of the MR task. These results suggest that the differences in MR performance due to ASD are different from sex-related differences in TD persons, in other words, ASD is not a simple and continuous extension of the male cognitive profile into the psychopathological range as the extreme male brain hypothesis (EMB) of ASD would suggest.

Cross-cultural sex differences in situational triggers of aggressive responses.

PubMed

Zajenkowska, Anna; Mylonas, Kostas; Lawrence, Claire; Konopka, Karolina; Rajchert, Joanna

2014-10-01

This paper examines male and female individual differences in situational triggers of aggressive responses (STAR) in three countries as well as cross-cultural sex differences in trait aggression (aggression questionnaire, AQ). Convenience sampling was employed (university students) for the descriptive correlational study (Poland N = 300, 63% female, mean age 21.86, SD = 2.12; UK N = 196, 60% female, mean age 20.48, SD = 3.79; Greece N = 299, 57% female, mean age 20.71, SD = 4.42). The results showed that the STAR scale is an equivalent construct across all three countries. Overall, females were more sensitive to both provocation (SP) and frustration (SF) than males. When controlling for trait aggression, Polish and Greek females scored similarly in SP and higher than UK females. No sex differences in SP or SF were found in the UK sample. Additionally, Polish participants scored the highest in SP. Furthermore, when trait aggression was removed, the Greek participants were most sensitive to frustration, whereas Polish and English participants' SF did not differ. We discuss the results with regard to intercultural differences between investigated countries. © 2014 International Union of Psychological Science.

Same-sex cohabiting elders versus different-sex cohabiting and married elders: effects of relationship status and sex of partner on economic and health outcomes.

PubMed

Baumle, Amanda K

2014-01-01

In this article, I use pooled data from the 2008-2010 American Community Surveys to examine outcomes for different-sex married, different-sex cohabiting, and same-sex cohabiting elders across several key economic and health indicators, as well as other demographic characteristics. The findings suggest that elders in same-sex cohabiting partnerships differ from those in different-sex marriages and different-sex cohabiting relationships in terms of both financial and health outcomes, and that women in same-sex cohabiting partnerships fare worse than men or women in other couple types. The results indicate that financial implications related to the sex of one's partner might be more predictive of economic and health outcomes in old age, rather than solely access to legal marriage. Nonetheless, findings suggest that individuals in same-sex cohabiting partnerships might experience worse outcomes in old age as a result of cumulative effects across the life course from both the sex of their partner (in the case of female couples) as well as their lack of access to benefits associated with marriage. Accordingly, these findings demonstrate that persons in same-sex cohabiting partnerships require unique policy considerations to address health and economic concerns in old age. Copyright © 2013 Elsevier Inc. All rights reserved.

Sex Differences in Toddlers with Autism Spectrum Disorders

ERIC Educational Resources Information Center

Carter, Alice S.; Black, David O.; Tewani, Sonia; Connolly, Christine E.; Kadlec, Mary Beth; Tager-Flusberg, Helen

2007-01-01

Although autism spectrum disorders (ASD) prevalence is higher in males than females, few studies address sex differences in developmental functioning or clinical manifestations. Participants in this study of sex differences in developmental profiles and clinical symptoms were 22 girls and 68 boys with ASD (mean age = 28 months). All children…

Sex Differences and Depression in Puerto Rico.

ERIC Educational Resources Information Center

Canino, Glorisa J.; And Others

1987-01-01

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)

Same, Different, Equal: Rethinking Single-Sex Schooling.

ERIC Educational Resources Information Center

Salomone, Rosemary C.

This book presents an argument for supporting single-sex education. It examines the history and politics of gender and schooling; philosophical and psychological theories of sameness and differences; findings on educational achievement and performance; research evidence on single-sex schooling; and the legal questions that arise from single-sex…

Sex Attracts: Investigating Individual Differences in Attentional Bias to Sexual Stimuli

PubMed Central

Kagerer, Sabine; Wehrum, Sina; Klucken, Tim; Walter, Bertram; Vaitl, Dieter; Stark, Rudolf

2014-01-01

We investigated the impact of sexual stimuli and the influence of sexual motivation on the performance in a dot-probe task and a line-orientation task in a large sample of males and females. All pictures (neutral, erotic) were rated on the dimensions of valence, arousal, disgust, and sexual arousal. Additionally, questionnaires measuring sexual interest/desire/motivation were employed. The ratings of the sexual stimuli point to a successful picture selection because sexual arousal did not differ between the sexes. The stimuli were equally arousing for men and women. Higher scores in the employed questionnaires measuring sexual interest/desire/motivation led to higher sexual arousal ratings of the sex pictures. Attentional bias towards sex pictures was observed in both experimental tasks. The attentional biases measured by the dot-probe and the line-orientation task were moderately intercorrelated suggesting attentional bias as a possible marker for a sex-attention trait. Finally, only the sexual sensation seeking score correlated with the attentional biases of the two tasks. Future research is needed to increase the predictive power of these indirect measures of sexual interest. PMID:25238545

Nicotinamide Adenine Dinucleotide (NAD+) and Nicotinamide: Sex Differences in Cerebral Ischemia

PubMed Central

Siegel, Chad S.; McCullough, Louise D.

2013-01-01

Background Previous literature suggests that cell death pathways activated after cerebral ischemia differ between the sexes. While caspase-dependent mechanisms predominate in the female brain, caspase-independent cell death induced by activation of Poly (ADP-ribose) polymerase (PARP) predominates in the male brain. PARP-1 gene deletion decreases infarction volume in the male brain, but paradoxically increases damage in PARP-1 knockout females. Purpose This study examined stroke induced changes in NAD+, a key energy molecule involved in PARP-1 activation in both sexes. Methods Mice were subjected to Middle Cerebral Artery Occlusion and NAD+ levels were assessed. Caspase-3 activity and nuclear translocation was assessed 6 hours after ischemia. In additional cohorts, Nicotinamide (500mg/kg i.p.) a precursor of NAD+ or vehicle was administered and infarction volume was measured 24 hours after ischemia. Results Males have higher baseline NAD+ levels than females. Significant stroke-induced NAD+ depletion occurred in males and ovariectomized females but not in intact females. PARP-1 deletion prevented the stroke induced loss in NAD+ in males, but worsened NAD+ loss in PARP-1 deficient females. Preventing NAD+ loss with nicotinamide reduced infarct in wild-type males and PARP-1 knockout mice of both sexes, with no effect in WT females. Caspase-3 activity was significantly increased in PARP-1 knockout females compared to males and wild-type females, this was reversed with nicotinamide. Conclusions Sex differences exist in baseline and stroke-induced NAD+ levels. Nicotinamide protected males and PARP knockout mice, but had minimal effects in the wild-type female brain. This may be secondary to differences in energy metabolism between the sexes. PMID:23403179

Sex differences in brain activation to emotional stimuli: a meta-analysis of neuroimaging studies.

PubMed

Stevens, Jennifer S; Hamann, Stephan

2012-06-01

Substantial sex differences in emotional responses and perception have been reported in previous psychological and psychophysiological studies. For example, women have been found to respond more strongly to negative emotional stimuli, a sex difference that has been linked to an increased risk of depression and anxiety disorders. The extent to which such sex differences are reflected in corresponding differences in regional brain activation remains a largely unresolved issue, however, in part because relatively few neuroimaging studies have addressed this issue. Here, by conducting a quantitative meta-analysis of neuroimaging studies, we were able to substantially increase statistical power to detect sex differences relative to prior studies, by combining emotion studies which explicitly examined sex differences with the much larger number of studies that examined only women or men. We used an activation likelihood estimation approach to characterize sex differences in the likelihood of regional brain activation elicited by emotional stimuli relative to non-emotional stimuli. We examined sex differences separately for negative and positive emotions, in addition to examining all emotions combined. Sex differences varied markedly between negative and positive emotion studies. The majority of sex differences favoring women were observed for negative emotion, whereas the majority of the sex differences favoring men were observed for positive emotion. This valence-specificity was particularly evident for the amygdala. For negative emotion, women exhibited greater activation than men in the left amygdala, as well as in other regions including the left thalamus, hypothalamus, mammillary bodies, left caudate, and medial prefrontal cortex. In contrast, for positive emotion, men exhibited greater activation than women in the left amygdala, as well as greater activation in other regions including the bilateral inferior frontal gyrus and right fusiform gyrus. These meta

Different Rights, Different Perspectives: Observations on the Same-Sex Marriage Debate.

ERIC Educational Resources Information Center

Howard, J. Paul R.

2003-01-01

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…

Sex differences in seizure types and symptoms.

PubMed

Carlson, Chad; Dugan, Patricia; Kirsch, Heidi E; Friedman, Daniel

2014-12-01

Despite the increasing interest in sex differences in disease manifestations and responses to treatment, very few data are available on sex differences in seizure types and semiology. The Epilepsy Phenome/Genome Project (EPGP) is a large-scale, multi-institutional, collaborative study that aims to create a comprehensive repository of detailed clinical information and DNA samples from a large cohort of people with epilepsy. We used this well-characterized cohort to explore differences in seizure types as well as focal seizure symptoms between males and females. We reviewed the EPGP database and identified individuals with generalized epilepsy of unknown etiology (GE) (n = 760; female: 446, male: 314), nonacquired focal epilepsy (NAFE) (n = 476; female: 245, male: 231), or both (n = 64; female: 33, male: 31). Demographic data along with characterization of seizure type and focal seizure semiologies were examined. In GE, males reported atonic seizures more frequently than females (6.5% vs. 1.7%; p < 0.001). No differences were observed in other generalized seizure types. In NAFE, no sex differences were seen for seizure types with or without alteration of consciousness or progression to secondary generalization. Autonomic (16.4% vs. 26.6%; p = 0.005), psychic (26.7% vs. 40.3%; p = 0.001), and visual (10.3% vs. 19.9%; p = 0.002) symptoms were more frequently reported in females than males. Specifically, of psychic symptoms, more females than males endorsed déjà vu (p = 0.001) but not forced thoughts, derealization/depersonalization, jamais vu, or fear. With corrections for multiple comparisons, there were no significant differences in aphasic, motor, somatosensory, gustatory, olfactory, auditory, vertiginous, or ictal headache symptoms between sexes. Significant differences between the sexes were observed in the reporting of atonic seizures, which were more common in males with GE, and for autonomic, visual, and psychic symptoms associated with NAFE, which were more

Sex Differences in Seizure Types and Symptoms

PubMed Central

Carlson, Chad; Dugan, Patricia; Kirsch, Heidi E; Friedman, Daniel

2014-01-01

Background Despite the increasing interest in sex differences in disease manifestations and responses to treatment, very few data are available on sex differences in seizure types and semiology. The Epilepsy Phenome/Genome Project (EPGP) is a large-scale, multi-institutional, collaborative study that aims to create a comprehensive repository of detailed clinical information and DNA samples from a large cohort of people with epilepsy. We used this well-characterized cohort to explore differences in seizure types as well as focal seizure symptoms between males and females. Methods We reviewed the EPGP database and identified individuals with generalized epilepsy of unknown etiology (GE) (n=760; female 446, male 314), non-acquired focal epilepsy (NAFE) (n=476; female 245, male 231), or both (n=64; female 33, male 31). Demographic data along with characterization of seizure type and focal seizure semiologies were examined. Results In GE, males reported atonic seizures more frequently than females (6.5% vs. 1.7%; p<0.001). No differences were observed in other generalized seizure types. In NAFE, no sex differences were seen for seizure types with or without alteration of consciousness or progression to secondary generalization. Autonomic (16.4% vs. 26.6%; p=0.005), psychic (26.7% vs. 40.3%; p=0.001), and visual symptoms (10.3% vs. 19.9%; p=0.002) were more frequently reported in females than males. Specifically, of psychic symptoms, more females than males endorsed déjà vu (p=0.001), but not forced thoughts, derealization/depersonalization, jamais vu, or fear. With corrections for multiple comparisons, there were no significant differences in aphasic, motor, somatosensory, gustatory, olfactory, auditory, vertiginous, or ictal headache symptoms between sexes. Conclusions Significant differences between the sexes were observed in the reporting of atonic seizures, which was more common in males with GE, and for autonomic, visual, and psychic symptoms associated with NAFE

Potential Reporting Bias in Neuroimaging Studies of Sex Differences.

PubMed

David, Sean P; Naudet, Florian; Laude, Jennifer; Radua, Joaquim; Fusar-Poli, Paolo; Chu, Isabella; Stefanick, Marcia L; Ioannidis, John P A

2018-04-17

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.

A study of the dynamics of sex differences in adulthood.

PubMed

Trofimova, Irina

2013-01-01

Studies of gender differences using primarily young individuals show that males, on average, perform better than females in physical activities but worse than females on tests of verbal abilities. There is however a controversy about the existence of these sex differences in adulthood. Our study used 1271 participants from four cultural backgrounds (Chinese, multi-generation Canadians, Indu-Canadians, and European-Canadians) divided in five age groups. We measured sex differences in the time required for participants to complete a lexical task experiment, and also assessed their verbal tempo and physical endurance using a validated temperament test (Structure of Temperament Questionnaire). We found a significant female advantage in time on the lexical task and on the temperament scale of social-verbal tempo, and a male advantage on the temperament scale of physical endurance. These sex differences, however, were more pronounced in young age groups (17-24), fading in older groups. This "middle age-middle sex" phenomenon suggests that sex differences in these two types of abilities observed in younger groups might be "a matter of age," and should not be attributed to gender in general. A one-dimensional approach to sex differences (common in meta-analytic studies) therefore overlooks a possible interaction of sex differences with age.

Sex differences and sexual orientation differences in personality: findings from the BBC Internet survey.

PubMed

Lippa, Richard A

2008-02-01

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.

The Sex Difference in Depression across 29 Countries

ERIC Educational Resources Information Center

Hopcroft, Rosemary L.; Bradley, Dana Burr

2007-01-01

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…

Serial Comparison Processes and Sex Differences in Clerical Speed.

ERIC Educational Resources Information Center

Majeres, Raymond L.

1988-01-01

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…

Sex differences in voice onset time: A developmental study of phonetic context effects in British English

NASA Astrophysics Data System (ADS)

Whiteside, Sandra P.; Henry, Luisa; Dobbin, Rachel

2004-08-01

Voice onset time (VOT) data for the plosives /p b t d k g/ in two vowel contexts (eye opena) for 5 groups of 46 boys and girls aged 5; 8 (5 years, 8 months) to 13;2 years were investigated to examine patterns of sex differences. Results indicated that there was some evidence of females displaying longer VOT values than the males. In addition, these were found to be most marked for the data of the 13;2-year olds. Furthermore, the sex differences in the VOT values displayed phonetic context effects. For example, the greatest sex differences were observed for the voiceless plosives, and within the context of the vowel /i/.

The Science of Sex Differences in Science and Mathematics

PubMed Central

Halpern, Diane F.; Benbow, Camilla P.; Geary, David C.; Gur, Ruben C.; Hyde, Janet Shibley; Gernsbacher, Morton Ann

2014-01-01

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

Sex differences in human epilepsy.

PubMed

Savic, Ivanka

2014-09-01

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.

Sex differences in cognitive regulation of psychosocial achievement stress: brain and behavior.

PubMed

Kogler, Lydia; Gur, Ruben C; Derntl, Birgit

2015-03-01

Although cognitive regulation of emotion has been extensively examined, there is a lack of studies assessing cognitive regulation in stressful achievement situations. This study used functional magnetic resonance imaging in 23 females and 20 males to investigate cognitive downregulation of negative, stressful sensations during a frequently used psychosocial stress task. Additionally, subjective responses, cognitive regulation strategies, salivary cortisol, and skin conductance response were assessed. Subjective response supported the experimental manipulation by showing higher anger and negative affect ratings after stress regulation than after the mere exposure to stress. On a neural level, right middle frontal gyrus (MFG) and right superior temporal gyrus (STG) were more strongly activated during regulation than nonregulation, whereas the hippocampus was less activated during regulation. Sex differences were evident: after regulation females expressed higher subjective stress ratings than males, and these ratings were associated with right hippocampal activation. In the nonregulation block, females showed greater activation of the left amygdala and the right STG during stress than males while males recruited the putamen more robustly in this condition. Thus, cognitive regulation of stressful achievement situations seems to induce additional stress, to recruit regions implicated in attention integration and working memory and to deactivate memory retrieval. Stress itself is associated with greater activation of limbic as well as attention areas in females than males. Additionally, activation of the memory system during cognitive regulation of stress is associated with greater perceived stress in females. Sex differences in cognitive regulation strategies merit further investigation that can guide sex sensitive interventions for stress-associated disorders. © 2014 Wiley Periodicals, Inc.

Sex differences in the expression of lung inflammatory mediators in response to ozone

PubMed Central

Cabello, Noe; Mishra, Vikas; Sinha, Utkarshna; DiAngelo, Susan L.; Chroneos, Zissis C.; Ekpa, Ndifreke A.; Cooper, Timothy K.; Caruso, Carla R.

2015-01-01

Sex differences in the incidence of respiratory diseases have been reported. Women are more susceptible to inflammatory lung disease induced by air pollution and show worse adverse pulmonary health outcomes than men. However, the mechanisms underlying these differences remain unknown. In the present study, we hypothesized that sex differences in the expression of lung inflammatory mediators affect sex-specific immune responses to environmental toxicants. We focused on the effects of ground-level ozone, a major air pollutant, in the expression and regulation of lung immunity genes. We exposed adult male and female mice to 2 ppm of ozone or filtered air (control) for 3 h. We compared mRNA levels of 84 inflammatory genes in lungs harvested 4 h postexposure using a PCR array. We also evaluated changes in lung histology and bronchoalveolar lavage fluid cell counts and protein content at 24 and 72 h postexposure. Our results revealed sex differences in lung inflammation triggered by ozone exposure and in the expression of genes involved in acute phase and inflammatory responses. Major sex differences were found in the expression of neutrophil-attracting chemokines (Ccl20, Cxcl5, and Cxcl2), the proinflammatory cytokine interleukin-6, and oxidative stress-related enzymes (Ptgs2, Nos2). In addition, the phosphorylation of STAT3, known to mediate IL-6-related immune responses, was significantly higher in ozone-exposed mice. Together, our observations suggest that a differential regulation of the lung immune response could be implicated in the observed increased susceptibility to adverse health effects from ozone observed in women vs. men. PMID:26342085

A meta-analysis of sex differences in human brain structure☆

PubMed Central

Ruigrok, Amber N.V.; Salimi-Khorshidi, Gholamreza; Lai, Meng-Chuan; Baron-Cohen, Simon; Lombardo, Michael V.; Tait, Roger J.; Suckling, John

2014-01-01

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

A meta-analysis of sex differences in human brain structure.

PubMed

Ruigrok, Amber N V; Salimi-Khorshidi, Gholamreza; Lai, Meng-Chuan; Baron-Cohen, Simon; Lombardo, Michael V; Tait, Roger J; Suckling, John

2014-02-01

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.

The Mandarin Childhood Autism Spectrum Test (CAST): Sex Differences

ERIC Educational Resources Information Center

Sun, Xiang; Allison, Carrie; Auyeung, Bonnie; Matthews, Fiona E.; Sharp, Stephen J.; Baron-Cohen, Simon; Brayne, Carol

2014-01-01

Sex differences in social and communication behaviours related to autism spectrum conditions (ASC) have been investigated mainly in Western populations. Little research has been done in Chinese populations. This study explored sex differences related to ASC characteristics by examining differences in item responses and score distributions in…

Sex- and Estrus-Dependent Differences in Rat Basolateral Amygdala

PubMed Central

Blume, Shannon R.; Freedberg, Mari; Vantrease, Jaime E.; Chan, Ronny; Padival, Mallika; Record, Matthew J.; DeJoseph, M. Regina; Urban, Janice H.

2017-01-01

Depression and anxiety are diagnosed almost twice as often in women, and the symptomology differs in men and women and is sensitive to sex hormones. The basolateral amygdala (BLA) contributes to emotion-related behaviors that differ between males and females and across the reproductive cycle. This hints at sex- or estrus-dependent features of BLA function, about which very little is known. The purpose of this study was to test whether there are sex differences or estrous cyclicity in rat BLA physiology and to determine their mechanistic correlates. We found substantial sex differences in the activity of neurons in lateral nuclei (LAT) and basal nuclei (BA) of the BLA that were associated with greater excitatory synaptic input in females. We also found strong differences in the activity of LAT and BA neurons across the estrous cycle. These differences were associated with a shift in the inhibition–excitation balance such that LAT had relatively greater inhibition during proestrus which paralleled more rapid cued fear extinction. In contrast, BA had relatively greater inhibition during diestrus that paralleled more rapid contextual fear extinction. These results are the first to demonstrate sex differences in BLA neuronal activity and the impact of estrous cyclicity on these measures. The shift between LAT and BA predominance across the estrous cycle provides a simple construct for understanding the effects of the estrous cycle on BLA-dependent behaviors. These results provide a novel framework to understand the cyclicity of emotional memory and highlight the importance of considering ovarian cycle when studying the BLA of females. SIGNIFICANCE STATEMENT There are differences in emotional responses and many psychiatric symptoms between males and females. This may point to sex differences in limbic brain regions. Here we demonstrate sex differences in neuronal activity in one key limbic region, the basolateral amygdala (BLA), whose activity fluctuates across the

Sex differences in navigation strategy and efficiency.

PubMed

Boone, Alexander P; Gong, Xinyi; Hegarty, Mary

2018-05-22

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.

Spatiotemporal mapping of sex differences during attentional processing.

PubMed

Neuhaus, Andres H; Opgen-Rhein, Carolin; Urbanek, Carsten; Gross, Melanie; Hahn, Eric; Ta, Thi Minh Tam; Koehler, Simone; Dettling, Michael

2009-09-01

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.

Sex difference in Double Iron ultra-triathlon performance

PubMed Central

2013-01-01

Background The present study examined the sex difference in swimming (7.8 km), cycling (360 km), running (84 km), and overall race times for Double Iron ultra-triathletes. Methods Sex differences in split times and overall race times of 1,591 men and 155 women finishing a Double Iron ultra-triathlon between 1985 and 2012 were analyzed. Results The annual number of finishes increased linearly for women and exponentially for men. Men achieved race times of 1,716 ± 243 min compared to 1,834 ± 261 min for women and were 118 ± 18 min (6.9%) faster (p < 0.01). Men finished swimming within 156 ± 63 min compared to women with 163 ± 31 min and were 8 ± 32 min (5.1 ± 5.0%) faster (p < 0.01). For cycling, men (852 ± 196 min) were 71 ± 70 min (8.3 ± 3.5%) faster than women (923 ± 126 min) (p < 0.01). Men completed the run split within 710 ± 145 min compared to 739 ± 150 min for women and were 30 ± 5 min (4.2 ± 3.4%) faster (p = 0.03). The annual three fastest men improved race time from 1,650 ± 114 min in 1985 to 1,339 ± 33 min in 2012 (p < 0.01). Overall race time for women remained unchanged at 1,593 ± 173 min with an unchanged sex difference of 27.1 ± 8.6%. In swimming, the split times for the annual three fastest women (148 ± 14 min) and men (127 ± 20 min) remained unchanged with an unchanged sex difference of 26.8 ± 13.5%. In cycling, the annual three fastest men improved the split time from 826 ± 60 min to 666 ± 18 min (p = 0.02). For women, the split time in cycling remained unchanged at 844 ± 54 min with an unchanged sex difference of 25.2 ± 7.3%. In running, the annual fastest three men improved split times from 649 ± 77 min to 532 ± 16 min (p < 0.01). For women, however, the split times remained unchanged at 657 ± 70 min with a stable sex difference of 32.4 ± 12.5%. Conclusions To summarize, the present findings showed that men were faster than women in Double Iron ultra-triathlon, men improved overall race times, cycling and running

The effects of death reminders on sex differences in prejudice toward gay men and lesbians.

PubMed

Webster, Russell J; Saucier, Donald A

2011-01-01

Terror management research shows that death reminders (mortality salience) increase prejudice toward worldview violators. Two studies investigated whether death reminders exacerbated differences in heterosexual men's and women's reports of sexual prejudice (negative attitudes based on sexual orientation). Results showed that following death reminders, sex differences in anti-gay discrimination and affective prejudice toward gay men (but not toward lesbians) were larger, and that these increased sex differences were mediated by gender role beliefs. The current studies suggest that researchers may attenuate the effects of death reminders by lessening the perceived worldview violation in addition to alleviating the existential terror of death.

Sex differences in chronometric mental rotation with human bodies.

PubMed

Voyer, Daniel; Jansen, Petra

2016-11-01

The present experiment investigated sex differences across stimulus types in a chronometric mental rotation task. The working hypothesis was that human bodies as stimuli would reduce the magnitude of sex differences compared to cubes as stimuli, from the embodied cognition perspective. One hundred and twenty participants, 60 men and 60 women solved chronometric mental rotation items with Shepard-Metzler cube figures, head-cubes, and human bodies, all designed so that they were similar in shape. Two figures of a given stimulus type were presented on the screen and participants had to judge if both items were mirrored or non-mirrored. Results showed better mental rotation performance with human bodies than with other types of stimuli for both sexes, although the effect of stimulus type was more pronounced in men than in women. Furthermore, regardless of stimulus type, men were more accurate than women. Altogether, the results suggest that sex differences are not reduced when human bodies are used as stimuli in a chronometric task. Implications for accounts of sex differences in mental rotations are discussed.

Sex differences and hormonal effects on gut microbiota composition in mice.

PubMed

Org, Elin; Mehrabian, Margarete; Parks, Brian W; Shipkova, Petia; Liu, Xiaoqin; Drake, Thomas A; Lusis, Aldons J

2016-07-03

We previously reported quantitation of gut microbiota in a panel of 89 different inbred strains of mice, and we now examine the question of sex differences in microbiota composition. When the total population of 689 mice was examined together, several taxa exhibited significant differences in abundance between sexes but a larger number of differences were observed at the single strain level, suggesting that sex differences can be obscured by host genetics and environmental factors. We also examined a subset of mice on chow and high fat diets and observed sex-by-diet interactions. We further investigated the sex differences using gonadectomized and hormone treated mice from 3 different inbred strains. Principal coordinate analysis with unweighted UniFrac distances revealed very clear effects of gonadectomy and hormone replacement on microbiota composition in all 3 strains. Moreover, bile acid analyses showed gender-specific differences as well as effects of gonodectomy, providing one possible mechanism mediating sex differences in microbiota composition.

A preliminary study of sex differences in brain activation during a spatial navigation task in healthy adults.

PubMed

Sneider, Jennifer Tropp; Sava, Simona; Rogowska, Jadwiga; Yurgelun-Todd, Deborah A

2011-10-01

The hippocampus plays a significant role in spatial memory processing, with sex differences being prominent on various spatial tasks. This study examined sex differences in healthy adults, using functional magnetic resonance imaging (fMRI) in areas implicated in spatial processing during navigation of a virtual analogue of the Morris water-maze. There were three conditions: learning, hidden, and visible control. There were no significant differences in performance measures. However, sex differences were found in regional brain activation during learning in the right hippocampus, right parahippocampal gyrus, and the cingulate cortex. During the hidden condition, the hippocampus, parahippocampal gyrus, and cingulate cortex were activated in both men and women. Additional brain areas involved in spatial processing may be recruited in women when learning information about the environment, by utilizing external cues (landmarks) more than do men, contributing to the observed sex differences in brain activation.

Sex differences in juvenile mouse social behavior are influenced by sex chromosomes and social context.

PubMed

Cox, K H; Rissman, E F

2011-06-01

Play behavior in juvenile primates, rats and other species is sexually dimorphic, with males showing more play than females. In mice, sex differences in juvenile play have only been examined in out-bred CD-1 mice. In this strain, contrary to other animals, male mice display less play soliciting than females. Using an established same-sex dyadic interaction test, we examined play in in-bred C57BL/6J (B6) 21-day-old mice. When paired with non-siblings, males tended to be more social than females, spending more time exploring the test cage. Females displayed significantly more anogenital sniffing and solicited play more frequently than did males. To determine if the origin of the sex difference was sex chromosome genes or gonadal sex, next we used the four core genotype mouse. We found significant interactions between gonadal sex and genotype for several behaviors. Finally, we asked if sibling pairs (as compared to non-siblings) would display qualitatively or quantitatively different behavior. In fact, XX females paired with a sibling were more social and less exploratory or investigative, whereas XY males exhibited less investigative and play soliciting behaviors in tests with siblings. Many neurobehavioral disorders, like autism spectrum disorder (ASD), are sexually dimorphic in incidence and patients interact less than normal with other children. Our results suggest that sex chromosome genes interact with gonadal hormones to shape the development of juvenile social behavior, and that social context can drastically alter sex differences. These data may have relevance for understanding the etiology of sexually dimorphic disorders such as ASD. © 2011 The Authors. Genes, Brain and Behavior © 2011 Blackwell Publishing Ltd and International Behavioural and Neural Genetics Society.

Multifaceted origins of sex differences in the brain

PubMed Central

2016-01-01

Studies of sex differences in the brain range from reductionistic cell and molecular analyses in animal models to functional imaging in awake human subjects, with many other levels in between. Interpretations and conclusions about the importance of particular differences often vary with differing levels of analyses and can lead to discord and dissent. In the past two decades, the range of neurobiological, psychological and psychiatric endpoints found to differ between males and females has expanded beyond reproduction into every aspect of the healthy and diseased brain, and thereby demands our attention. A greater understanding of all aspects of neural functioning will only be achieved by incorporating sex as a biological variable. The goal of this review is to highlight the current state of the art of the discipline of sex differences research with an emphasis on the brain and to contextualize the articles appearing in the accompanying special issue. PMID:26833829

Sex differences in parent-infant interaction during free play, departure, and separation.

PubMed

Weinraub, M; Frankel, J

1977-12-01

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.

Sex differences in cardiovascular and subjective stress reactions: prospective evidence in a realistic military setting.

PubMed

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

2014-01-01

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.

Sex Differences in Circadian Timing Systems: Implications for Disease

PubMed Central

Bailey, Matthew; Silver, Rae

2014-01-01

Virtually every eukaryotic cell has an endogenous circadian clock and a biological sex. These cell-based clocks have been conceptualized as oscillators whose phase can be reset by internal signals such as hormones, and external cues such as light. The present review highlights the inter-relationship between circadian clocks and sex differences. In mammals, the suprachiasmatic nucleus (SCN) serves as a master clock synchronizing the phase of clocks throughout the body. Gonadal steroid receptors are expressed in almost every site that receives direct SCN input. Here we review sex differences in the circadian timing system in the hypothalamic-pituitary-gonadal axis (HPG), the hypothalamicadrenal-pituitary (HPA) axis, and sleep-arousal systems. We also point to ways in which disruption of circadian rhythms within these systems differs in the sexes and is associated with dysfunction and disease. Understanding sex differentiated circadian timing systems can lead to improved treatment strategies for these conditions. PMID:24287074

Same-Sex and Different-Sex Parent Households and Child Health Outcomes: Findings from the National Survey of Children's Health.

PubMed

Bos, Henny M W; Knox, Justin R; van Rijn-van Gelderen, Loes; Gartrell, Nanette K

2016-04-01

Using the 2011-2012 National Survey of Children's Health data set, we compared spouse/partner relationships and parent-child relationships (family relationships), parenting stress, and children's general health, emotional difficulties, coping behavior, and learning behavior (child outcomes) in households of same-sex (female) versus different-sex continuously coupled parents with biological offspring. We assessed whether associations among family relationships, parenting stress, and child outcomes were different in the 2 household types. Parental and child characteristics were matched for 95 female same-sex parent and 95 different-sex parent households with children 6 to 17 years old. One parent per household was interviewed by telephone. Multivariate analyses of variance and multiple linear regressions were conducted. No differences were observed between household types on family relationships or any child outcomes. Same-sex parent households scored higher on parenting stress (95% confidence interval = 2.03-2.30) than different-sex parent households (95% confidence interval = 1.76-2.03), p = .006. No significant interactions between household type and family relationships or household type and parenting stress were found for any child outcomes. Children with female same-sex parents and different-sex parents demonstrated no differences in outcomes, despite female same-sex parents reporting more parenting stress. Future studies may reveal the sources of this parenting stress.

Mechanisms of Sex Differences in Fear and Posttraumatic Stress Disorder.

PubMed

Ramikie, Teniel Sonya; Ressler, Kerry J

2018-05-15

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.

Sex Differences in School Science Performance from Middle Childhood to Early Adolescence

ERIC Educational Resources Information Center

Haworth, Claire M. A.; Dale, Philip S.; Plomin, Robert

2010-01-01

We investigated whether the sexes differ in science performance before they make important course and career selections. We collected teacher-report data from a sample of children from the Twins Early Development Study (TEDS) assessed at ages 9, 10 and 12 years (N greater than 2500 pairs). In addition we developed a test of scientific enquiry and…

Sex Differences in Math-Intensive Fields.

PubMed

Ceci, Stephen J; Williams, Wendy M

2010-10-01

Despite impressive employment gains in many fields of science, women remain underrepresented in fields requiring intensive use of mathematics. Here we discuss three potential explanations for women's underrepresentation: (a) male-female mathematical and spatial ability gaps, (b) sex discrimination, and (c) sex differences in career preferences and lifestyle choices. Synthesizing findings from psychology, endocrinology, sociology, economics, and education leads to the conclusion that, among a combination of interrelated factors, preferences and choices-both freely made and constrained-are the most significant cause of women's underrepresentation.

Sex differences in subacute toxicity and hepatic microsomal metabolism of triptolide in rats.

PubMed

Liu, Li; Jiang, Zhenzhou; Liu, Jing; Huang, Xin; Wang, Tao; Liu, Jun; Zhang, Yun; Zhou, Zhixing; Guo, Jianlu; Yang, Lina; Chen, Yun; Zhang, Luyong

2010-04-30

Triptolide, a major active component of Tripterygium wilfordii Hook F (TWHF), has multiple pharmacological activities. However, its clinical use is often limited by its severe toxicity. In the present study, we evaluated the oral toxicity of triptolide in Sprague-Dawley rats for 28 days at the dosages of 0, 200 and 400microg/kg/day, respectively. Significant difference in the toxicity of triptolide at 400microg/kg was found between different sexes. The triptolide-treated female rats showed many abnormalities, including anorexia, diarrhea, leanness, suppression of weight gain and food intake, fatty liver, splenomegaly and atrophy of ovaries. In contrast, no such abnormalities were observed in male rats except for the significant reproductive toxicity. Furthermore, the metabolism of triptolide in liver microsomes from both sexes was investigated by HPLC. A greater rate of triptolide metabolism was observed in male rat hepatic microsomes, suggesting that one of the cytochrome P450s (CYPs) responsible for triptolide metabolism is male-specific or predominant at least. The inhibition experiments with CYP inhibitors showed that CYP3A and CYP2B were mainly involved in the metabolism of triptolide. In addition, since CYP3A2 is a male-predominant form in rats, significant sex difference in the metabolism of triptolide disappeared in vitro after anti-rat CYP3A2 antibody pretreatment. Results suggested that CYP3A2 made an important contribution to the sex-related metabolism of triptolide, which may result in the sex differences in triptolide toxicity.

Sex differences in a shoaling-boldness behavioral syndrome, but no link with aggression.

PubMed

Way, Gregory P; Kiesel, Alexis L; Ruhl, Nathan; Snekser, Jennifer L; McRobert, Scott P

2015-04-01

A behavioral syndrome is observed in a population when specific behaviors overlap at the individual level in different contexts. Here, we explore boldness and aggression personality spectra, the repeatability of shoaling, and possible associated correlations between the behaviors in a population of lab-reared zebrafish (Danio rerio). Our findings describe a sex-specific boldness-shoaling behavioral syndrome, as a link between boldness and shoaling behaviors is detected. The results indicate that bold males are likely to have a stronger shoaling propensity than shy males for unfamiliar conspecifics. Conversely, bold females are more likely to shoal than shy females, but only when presented with heterospecific individuals. Additionally, aggression does not correlate with boldness or shoaling propensity for either sex. A positive relationship between boldness and shoaling that differs by sex is contrary to most of the present literature, but could help to explain population dynamics and may also have evolutionary implications. Copyright © 2015 Elsevier B.V. All rights reserved.

Sex Differences in Psychiatric Disease: A Focus on the Glutamate System

PubMed Central

Wickens, Megan M.; Bangasser, Debra A.; Briand, Lisa A.

2018-01-01

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.

Sex differences in chronic stress effects on cognition in rodents.

PubMed

Luine, Victoria; Gomez, Juan; Beck, Kevin; Bowman, Rachel

2017-01-01

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.

Sex differences in chronic stress effects on cognition in rodents

PubMed Central

Luine, Victoria; Gomez, Juan; Beck, Kevin; Bowman, Rachel

2016-01-01

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. PMID:27566290

Sex Differences in Technical Communication: A Perspective from Social Role Theory

ERIC Educational Resources Information Center

Thompson, Isabelle

2004-01-01

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…

Sex differences in stress regulation of arousal and cognition.

PubMed

Bangasser, Debra A; Eck, Samantha R; Telenson, Alexander M; Salvatore, Madeleine

2018-04-01

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.

Sex differences on the judgment of line orientation task: a function of landmark presence and hormonal status.

PubMed

Goyette, Sharon Ramos; McCoy, John G; Kennedy, Ashley; Sullivan, Meghan

2012-02-28

It has been well-established that men outperform women on some spatial tasks. The tools commonly used to demonstrate this difference (e.g. The Mental Rotations Task) typically involve problems and solutions that are presented in a context devoid of referents. The study presented here assessed whether the addition of referents (or "landmarks") would attenuate the well-established sex difference on the judgment of line orientation task (JLOT). Three versions of the JLOT were presented in a within design. The first iteration contained the original JLOT (JLOT 1). JLOT 2 contained three "landmarks" or referents and JLOT 3 contained only one landmark. The sex difference on JLOT 1 was completely negated by the addition of three landmarks on JLOT 2 or the addition of one landmark on JLOT3. In addition, salivary testosterone was measured. In men, gains in performance on the JLOT due to the addition of landmarks were positively correlated with testosterone levels. This suggests that men with the highest testosterone levels benefited the most from the addition of landmarks. These data help to highlight different strategies used by men and women to solve spatial tasks. Copyright © 2011 Elsevier Inc. All rights reserved.

Few Sex Differences in Hospitalized Suicide Attempters Aged 70 and Above.

PubMed

Wiktorsson, Stefan; Rydberg Sterner, Therese; Mellqvist Fässberg, Madeleine; Skoog, Ingmar; Ingeborg Berg, Anne; Duberstein, Paul; Van Orden, Kimberly; Waern, Margda

2018-01-16

Relatively little research attention has been paid to sex issues in late life suicidal behaviour. The aim was to compare clinical characteristics of women and men aged 70+ who were hospitalized after a suicide attempt. We hypothesized higher depression and anxiety scores in women, and we expected to find that men would more often attribute the attempt to health problems and compromised autonomy. Participants (56 women and 47 men, mean age 80) were interviewed by a psychologist. In addition to psychiatric and somatic health assessments, participants responded to an open-ended question concerning attributions of the attempt. There were no sex differences in depression and anxiety. Forty-five percent of the men and 14% of the women had a history of substance use disorder ( p = 0.02). At least one serious physical disability was noted in 60.7% of the women and 53.2% of the men ( p = 0.55). Proportions attributing their attempt to somatic illness did not differ (women, 14.5% vs. men 17.4%, p = 0.79), and similar proportions attributed the attempt to reduced autonomy (women, 21.8% vs. men, 26.1%, p = 0.64). We found strikingly similar figures for depression scores, functional disability and attributions for attempting suicide in older men and women. Larger studies are needed in diverse settings as sex differences might be influenced by cultural context.

Evolving knowledge of sex differences in brain structure, function, and chemistry.

PubMed

Cosgrove, Kelly P; Mazure, Carolyn M; Staley, Julie K

2007-10-15

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.

Explaining the Sex Difference in Dyslexia

ERIC Educational Resources Information Center

Arnett, Anne B.; Pennington, Bruce F.; Peterson, Robin L.; Willcutt, Erik G.; DeFries, John C.; Olson, Richard K.

2017-01-01

Background: Males are diagnosed with dyslexia more frequently than females, even in epidemiological samples. This may be explained by greater variance in males' reading performance. Methods: We expand on previous research by rigorously testing the variance difference theory, and testing for mediation of the sex difference by cognitive correlates.…

Sex-dependent differences in voluntary physical activity.

PubMed

Rosenfeld, Cheryl S

2017-01-02

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.

Sex differences in verbal and visual-spatial tasks under different hemispheric visual-field presentation conditions.

PubMed

Boyle, Gregory J; Neumann, David L; Furedy, John J; Westbury, H Rae

2010-04-01

This paper reports sex differences in cognitive task performance that emerged when 39 Australian university undergraduates (19 men, 20 women) were asked to solve verbal (lexical) and visual-spatial cognitive matching tasks which varied in difficulty and visual field of presentation. Sex significantly interacted with task type, task difficulty, laterality, and changes in performance across trials. The results revealed that the significant individual-differences' variable of sex does not always emerge as a significant main effect, but instead in terms of significant interactions with other variables manipulated experimentally. Our results show that sex differences must be taken into account when conducting experiments into human cognitive-task performance.

Sex Differences in the Mental Rotation of Chemistry Representations

ERIC Educational Resources Information Center

Stieff, Mike

2013-01-01

Mental-rotation ability modestly predicts chemistry achievement. As such, sex differences in mental-rotation ability have been implicated as a causal factor that can explain sex differences in chemistry achievement and degree attainment. Although there is a correlation between mental-rotation ability and chemistry achievement, laboratory and field…

Is There a Sex Ratio Difference in the Familial Aggregation of Specific Language Impairment? A Meta-Analysis

ERIC Educational Resources Information Center

Whitehouse, Andrew J. O.

2010-01-01

Purpose: Specific language impairment (SLI) is known to aggregate in families. Debate exists on whether the male sex presents an additional risk for SLI. This meta-analysis examined whether there is a sex ratio difference in the risk for impairment among family members of an SLI proband and whether this is mediated by assessment method (direct…

Gender differences? Internet use and parent-child communication about sex toward sexual attitudes among early adolescents in Taiwan.

PubMed

Tseng, Ying-Hua; Weng, Chia-Sui; Kuo, Shih-Hsien; Chou, Fan-Hao; Yang, Yi-Hsin; Chiang, Li-Chi

2015-06-01

With the progress of information technology, early adolescents are able to access sex-related information through the Internet easily. This information has been shown to have a significant influence on the sexual health of this population. In addition, parent-child communications about sex affect the sexual health of adolescents. Few empirical studies have focused on early adolescents and gender differences. This study explores gender differences between early adolescents in terms of the use of the Internet to obtain sex-related information, parent-child communication, and sex-related knowledge and attitudes. This cross-sectional and comparative study uses an analysis of covariance and a hierarchical regression for data analysis. The researchers recruited 457 sixth-grade boys (n = 204) and girls (n = 253) in southern Taiwan as participants and used a structured questionnaire to collect data. Participants exhibited significant differences in terms of Internet usage behavior, parent-child communications about sex, and sex-related knowledge and sexual attitudes. The male participants spent more time on "recreation and entertainment" activities on the Internet, whereas their female peers spent significantly more time searching for information. Regarding parent-child communications about sex, girls had better mother-child communications than boys. In addition, no gender-based difference was found for father-child communications about sex. The knowledge of physical changes occurring during puberty and of menstrual healthcare among female participants was superior to their male counterparts. Girls had a more informed sexual attitude, particularly with regard to issues of gender roles, relationships with the opposite gender, and the social aspects of sex. Sex-related knowledge and parent-child communication about sex were the two major predictors of sexual attitudes for boys and girls, respectively. To develop healthy sexual attitudes among early adolescents, nursing

Sex Differences in Human Fatigability: Mechanisms and Insight to Physiological Responses

PubMed Central

Hunter, Sandra K.

2014-01-01

Sex-related differences in physiology and anatomy are responsible for profound differences in neuromuscular performance and fatigability between men and women. Women are usually less fatigable than men for similar intensity isometric fatiguing contractions. This sex difference in fatigability, however, is task specific because different neuromuscular sites will be stressed when the requirements of the task are altered, and the stress on these sites can differ for men and women. Task variables that can alter the sex difference in fatigue include the type, intensity and speed of contraction, the muscle group assessed, and the environmental conditions. Physiological mechanisms that are responsible for sex-based differences in fatigability may include activation of the motor neuron pool from cortical and subcortical regions, synaptic inputs to the motor neuron pool via activation of metabolically-sensitive small afferent fibres in the muscle, muscle perfusion, and skeletal muscle metabolism and fibre type properties. Non-physiological factors such as the sex bias of studying more males than females in human and animal experiments can also mask a true understanding of the magnitude and mechanisms of sex-based differences in physiology and fatigability. Despite recent developments, there is a tremendous lack of understanding of sex differences in neuromuscular function and fatigability, the prevailing mechanisms and the functional consequences. This review emphasises the need to understand sex-based differences in fatigability in order to shed light on the benefits and limitations that fatigability can exert for men and women during daily tasks, exercise performance, training and rehabilitation in both health and disease. PMID:24433272

Cognitive sex differences are not magnified as a function of age, sex hormones, or puberty development during early adolescence.

PubMed

Herlitz, Agneta; Reuterskiöld, Lena; Lovén, Johanna; Thilers, Petra P; Rehnman, Jenny

2013-01-01

Are cognitive sex differences magnified by individual differences in age, sex hormones, or puberty development? Cross-sectional samples of 12- to 14-year-old boys (n = 85) and girls (n = 102) completed tasks assessing episodic memory, face recognition, verbal fluency, and mental rotations. Blood estradiol, free testosterone, and self-rated puberty scores were obtained. Sex differences were found on all cognitive measures. However, the magnitude was not larger for older children, hormones and cognitive performance were not associated, and early maturers did not perform better than late maturers. Thus, cognitive sex differences were not associated with age, levels of sex hormones, or puberty development.

Explaining sex differences in reactions to relationship infidelities: comparisons of the roles of sex, gender, beliefs, attachment, and sociosexual orientation.

PubMed

Brase, Gary L; Adair, Lora; Monk, Kale

2014-02-04

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.

Black-White Differences in Sex and Contraceptive Use Among Young Women

PubMed Central

Kusunoki, Yasamin; Barber, Jennifer S.; Ela, Elizabeth J.; Bucek, Amelia

2016-01-01

This study examines black-white and other sociodemographic differences in young women’s sexual and contraceptive behaviors, using new longitudinal data from a weekly journal-based study of 1,003 18- to 19-year-old women spanning 2.5 years. We investigate hypotheses about dynamic processes in these behaviors during early adulthood in order to shed light on persisting racial differences in rates of unintended pregnancies in the United States. We find that net of other sociodemographic characteristics and adolescent experiences with sex and pregnancy, black women spent less time in relationships and had sex less frequently in their relationships than white women, but did not differ in the number of relationships they formed or in their frequency or consistency of contraceptive use within relationships. Black women were more likely to use less effective methods for pregnancy prevention (e.g., condoms) than white women, who tended to use more effective methods (e.g., oral contraceptives). And although the most effective method for pregnancy prevention—long-acting reversible contraception (LARC)—was used more often by black women than white women, LARC use was low in both groups. In addition, black women did not differ from white women in their number of discontinuations or different methods used and had fewer contraceptive method switches. Further, we find that net of race and adolescent experiences with sex and pregnancy, women from more-disadvantaged backgrounds had fewer and longer (and thus potentially more serious) relationships, used contraception less frequently (but not less consistently), and used less effective methods (condoms) than women from more-advantaged backgrounds. PMID:27624320

Black-White Differences in Sex and Contraceptive Use Among Young Women.

PubMed

Kusunoki, Yasamin; Barber, Jennifer S; Ela, Elizabeth J; Bucek, Amelia

2016-10-01

This study examines black-white and other sociodemographic differences in young women's sexual and contraceptive behaviors, using new longitudinal data from a weekly journal-based study of 1,003 18- to 19-year-old women spanning 2.5 years. We investigate hypotheses about dynamic processes in these behaviors during early adulthood in order to shed light on persisting racial differences in rates of unintended pregnancies in the United States. We find that net of other sociodemographic characteristics and adolescent experiences with sex and pregnancy, black women spent less time in relationships and had sex less frequently in their relationships than white women, but did not differ in the number of relationships they formed or in their frequency or consistency of contraceptive use within relationships. Black women were more likely to use less effective methods for pregnancy prevention (e.g., condoms) than white women, who tended to use more effective methods (e.g., oral contraceptives). And although the most effective method for pregnancy prevention-long-acting reversible contraception (LARC)-was used more often by black women than white women, LARC use was low in both groups. In addition, black women did not differ from white women in their number of discontinuations or different methods used and had fewer contraceptive method switches. Further, we find that net of race and adolescent experiences with sex and pregnancy, women from more-disadvantaged backgrounds had fewer and longer (and thus potentially more serious) relationships, used contraception less frequently (but not less consistently), and used less effective methods (condoms) than women from more-advantaged backgrounds.

Sex Differences in Children's Discrepant Perceptions of Peer Acceptance

ERIC Educational Resources Information Center

Smith, Stephanie D.; Van Gessel, Christine A.; David-Ferdon, Corinne; Kistner, Janet A.

2013-01-01

Sex differences in children's play patterns during middle childhood are thought to promote greater awareness of social acceptance among girls compared with boys. The present study posited that girls are more discerning of peer acceptance than are boys; however, these sex differences were predicted to vary depending on how discrepant perceptions…

Sex difference in leukocyte telomere length is ablated in opposite-sex co-twins

PubMed Central

Benetos, Athanase; Dalgård, Christine; Labat, Carlos; Kark, Jeremy D; Verhulst, Simon; Christensen, Kaare; Kimura, Masayuki; Horvath, Kent; Kyvik, Kirsten Ohm; Aviv, Abraham

2014-01-01

Background: In eutherian mammals and in humans, the female fetus may be masculinized while sharing the intra-uterine environment with a male fetus. Telomere length (TL), as expressed in leukocytes, is heritable and is longer in women than in men. The main determinant of leukocyte TL (LTL) is LTL at birth. However, LTL is modified by age-dependent attrition. Methods: We studied LTL dynamics (LTL and its attrition) in adult same-sex (monozygotic, n = 268; dizygotic, n = 308) twins and opposite-sex (n = 144) twins. LTL was measured by Southern blots of the terminal restriction fragments. Results: We observed that in same-sex (both monozygotic and dizygotic) twins, as reported in singletons, LTL was longer in females than in males [estimate ± standard error (SE):163 ± 63 bp, P < 0.01]. However, in opposite-sex twins, female LTL was indistinguishable from that of males (−31 ± 52 bp, P = 0.6), whereas male LTL was not affected. Findings were similar when the comparison was restricted to opposite-sex and same-sex dizygotic twins (females relative to males: same-sex: 188 ± 90 bp, P < 0.05; other-sex: −32 ± 64 bp, P = 0.6). Conclusions: These findings are compatible with masculinization of the female fetus in opposite-sex twins. They suggest that the sex difference in LTL, seen in the general population, is largely determined in utero, perhaps by the intrauterine hormonal environment. Further studies in newborn twins are warranted to test this thesis. PMID:25056338

Sex Differences in the Relationship between Harsh Discipline and Conduct Problems

ERIC Educational Resources Information Center

Lysenko, Laura J.; Barker, Edward D.; Jaffee, Sara R.

2013-01-01

Research on sex differences in antisocial behaviour may shed light on the causes of childhood antisocial behaviour. Using a longitudinal design, we tested whether there were sex differences in the amount of harsh discipline children received or in the effect of harsh discipline and whether this accounted for sex differences in later conduct…

Sex-Differences, Handedness, and Lateralization in the Iowa Gambling Task

PubMed Central

Singh, Varsha

2016-01-01

In a widely used decision-making task, the Iowa Gambling Task (IGT), male performance is observed to be superior to that of females, and is attributed to right lateralization (i.e., right hemispheric dominance). It is as yet unknown whether sex-differences in affect and motor lateralization have implications for sex-specific lateralization in the IGT, and specifically, whether sex-difference in performance in the IGT changes with right-handedness or with affect lateralization (decision valence, and valence-directed motivation). The present study (N = 320; 160 males) examined the effects of right-handedness (right-handedness vs. non-right-handedness) as a measure of motor lateralization, decision valence (reward vs. punishment IGT), and valence-directedness of task motivation (valence-directed vs. non-directed instructions), as measures of affective lateralization on IGT decision making. Analyses of variance revealed that both male and female participants showed valence-induced inconsistencies in advantageous decision-making; however, right-handed females made more disadvantageous decisions in a reward IGT. These results suggest that IGT decision-making may be largely right-lateralized in right-handed males, and show that sex and lateralized differences (motor and affect) have implications for sex-differences in IGT decision-making. Implications of the results are discussed with reference to lateralization and sex-differences in cognition. PMID:27303316

Neural Correlates of Sex/Gender Differences in Humor Processing for Different Joke Types.

PubMed

Chan, Yu-Chen

2016-01-01

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

Neural Correlates of Sex/Gender Differences in Humor Processing for Different Joke Types

PubMed Central

Chan, Yu-Chen

2016-01-01

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

Sex differences in neural activation following different routes of oxytocin administration in awake adult rats.

PubMed

Dumais, Kelly M; Kulkarni, Praveen P; Ferris, Craig F; Veenema, Alexa H

2017-07-01

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.

Loss of T cells influences sex differences in behavior and brain structure.

PubMed

Rilett, Kelly C; Friedel, Miriam; Ellegood, Jacob; MacKenzie, Robyn N; Lerch, Jason P; Foster, Jane A

2015-05-01

Clinical and animal studies demonstrate that immune-brain communication influences behavior and brain function. Mice lacking T cell receptor β and δ chains were tested in the elevated plus maze, open field, and light-dark test and showed reduced anxiety-like behavior compared to wild type. Interestingly sex differences were observed in the behavioural phenotype of TCRβ-/-δ- mice. Specifically, female TCRβ-/-δ- mice spent more time in the light chamber compared to wild type females, whereas male TCRβ-/-δ- spent more time in the center of the open field compared to wild type males. In addition, TCRβ-/-δ- mice did not show sex differences in activity-related behaviors observed in WT mice. Ex vivo brain imaging (7 Tesla MRI) revealed volume changes in hippocampus, hypothalamus, amygdala, periaqueductal gray, and dorsal raphe and other brain regions between wild type and T cell receptor knockout mice. There was also a loss of sexual dimorphism in brain volume in the bed nucleus of the stria terminalis, normally the most sexually dimorphic region in the brain, in immune compromised mice. These data demonstrate the presence of T cells is important in the development of sex differences in CNS circuitry and behavior. Copyright © 2015 Elsevier Inc. All rights reserved.

Exploring sex and gender differences in sleep health: a Society for Women's Health Research Report.

PubMed

Mallampalli, Monica P; Carter, Christine L

2014-07-01

Previous attempts have been made to address sleep disorders in women; however, significant knowledge gaps in research and a lack of awareness among the research community continue to exist. There is a great need for scientists and clinicians to consider sex and gender differences in their sleep research to account for the unique biology of women. To understand the role of sex differences in sleep and the state of women's sleep health research, the Society for Women's Health Research convened an interdisciplinary expert panel of well-established sleep researchers and clinicians for a roundtable meeting. Focused discussions on basic and clinical research along with a focus on specific challenges facing women with sleep-related problems and effective therapies led to the identification of knowledge gaps and the development of research-related recommendations. Additionally, sex differences in sleep disorders were noted and discussed in the context of underlying hormonal differences. Differences in sleep behavior and sleep disorders may not only be driven by biological factors but also by gender differences in the way women and men report symptoms. Progress has been made in identifying sex and gender differences in many areas of sleep, but major research gaps in the areas of epidemiology, sleep regulation, sleep quality, diagnosis, and treatment need to be addressed. Identifying the underlying nature of sex and gender differences in sleep research has potential to accelerate improved care for both men and women facilitating better diagnosis, treatment, and ultimately prevention of sleep disorders and related comorbid conditions.

Exploring Sex and Gender Differences in Sleep Health: A Society for Women's Health Research Report

PubMed Central

Mallampalli, Monica P.

2014-01-01

Abstract Previous attempts have been made to address sleep disorders in women; however, significant knowledge gaps in research and a lack of awareness among the research community continue to exist. There is a great need for scientists and clinicians to consider sex and gender differences in their sleep research to account for the unique biology of women. To understand the role of sex differences in sleep and the state of women's sleep health research, the Society for Women's Health Research convened an interdisciplinary expert panel of well-established sleep researchers and clinicians for a roundtable meeting. Focused discussions on basic and clinical research along with a focus on specific challenges facing women with sleep-related problems and effective therapies led to the identification of knowledge gaps and the development of research-related recommendations. Additionally, sex differences in sleep disorders were noted and discussed in the context of underlying hormonal differences. Differences in sleep behavior and sleep disorders may not only be driven by biological factors but also by gender differences in the way women and men report symptoms. Progress has been made in identifying sex and gender differences in many areas of sleep, but major research gaps in the areas of epidemiology, sleep regulation, sleep quality, diagnosis, and treatment need to be addressed. Identifying the underlying nature of sex and gender differences in sleep research has potential to accelerate improved care for both men and women facilitating better diagnosis, treatment, and ultimately prevention of sleep disorders and related comorbid conditions. PMID:24956068

Sex differences in general knowledge domains.

PubMed

Lynn, Richard; Ivanec, Dragutin; Zarevski, Predrag

2009-06-01

The aim of this study was to investigate some cognitive differences in highly comparable (according to age, education and motivation) samples of female and male university graduates in Croatia. Female (N=280; age X = 26.59; SD = 2.84) and male participants (N=96; age X = 26.99; SD = 2.99) were university graduates in economics, law humanities and social sciences applying for positions in public service. As part of the selection procedure, they were given a number of cognitive tests. The results were that men obtained higher average scores on the g-factor intelligence test, on the general knowledge tests of natural and social sciences, world religion and customs, and knowledge of current affairs. There were no significant sex differences on vocabulary, foreign language ability and general knowledge of culture. An analysis of covariance, with intelligence test as a covariate, showed that sex differences in general knowledge were present when intelligence was controlled.

Sex Differences in Animal Models of Decision-Making

PubMed Central

Orsini, Caitlin A.; Setlow, Barry

2016-01-01

The ability to weigh the costs and benefits of various options in order to make an adaptive decision is critical to an organism’s survival and well-being. Many psychiatric diseases are characterized by maladaptive decision-making, indicating the need to better understand the mechanisms underlying this process and the ways in which it is altered in pathological conditions. Great strides have been made in uncovering these mechanisms, but the majority of what is known comes from studies conducted solely in male subjects. In recent years, decision-making research has begun to include females to determine whether sex differences exist and to identify the mechanisms that contribute to such differences. This review will begin by describing studies that have examined sex differences in animal (largely rodent) models of decision-making. Possible explanations, both theoretical and biological, for such differences in decision- making will then be considered. The review will conclude with a discussion of the implications of sex differences in decision-making for understanding psychiatric conditions. PMID:27870448

Sex differences in normal age trajectories of functional brain networks.

PubMed

Scheinost, Dustin; Finn, Emily S; Tokoglu, Fuyuze; Shen, Xilin; Papademetris, Xenophon; Hampson, Michelle; Constable, R Todd

2015-04-01

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.

Sex Differences in Patient-Reported Poststroke Disability.

PubMed

White, Brandi M; Magwood, Gayenell S; Burns, Suzanne Perea; Ellis, Charles

2018-04-01

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.

Sex difference in the principal cytochrome P-450 for tributyltin metabolism in rats

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ohhira, Shuji; Enomoto, Mitsunori; Matsui, Hisao

Tributyltin is metabolized by cytochrome P-450 (CYP) system enzymes, and its metabolic fate may contribute to the toxicity of the chemical. In the present study, it is examined whether sex differences in the metabolism of tributyltin exist in rats. In addition, the in vivo and in vitro metabolism of tributyltin was investigated using rat hepatic CYP systems to confirm the principal CYP involved. A significant sex difference in metabolism occurred both in vivo and in vitro, suggesting that one of the CYPs responsible for tributyltin metabolism in rats is male specific or predominant at least. Eight cDNA-expressed rat CYPs, includingmore » typical phenobarbital (PB)-inducible forms and members of the CYP2C subfamily, were tested to determine their capability for tributyltin metabolism. Among the enzymes studied, a statistically significant dealkylation of tributyltin was mediated by CYP2C6 and 2C11. Furthermore, the sex difference in metabolism disappeared in vitro after anti-rat CYP2C11 antibody pretreatment because CYP2C11 is a major male-specific form in rats. These results indicate that CYP2C6 is the principal CYP for tributyltin metabolism in female rats, whereas CYP2C11 as well as 2C6 is involved in tributyltin metabolism in male rats, and it is suggested that CYP2C11 is responsible for the significant sex difference in the metabolism of tributyltin observed in rats.« less

Sex differences in abdominal aortic aneurysms.

PubMed

Boese, Austin C; Chang, Lin; Yin, Ke-Jie; Chen, Y Eugene; Lee, Jean-Pyo; Hamblin, Milton H

2018-06-01

Abdominal aortic aneurysm (AAA) is a vascular disorder with a high case fatality rate in the instance of rupture. AAA is a multifactorial disease, and the etiology is still not fully understood. AAA is more likely to occur in men, but women have a greater risk of rupture and worse prognosis. Women are reportedly protected against AAA possibly by premenopausal levels of estrogen and are, on average, diagnosed at older ages than men. Here, we review the present body of research on AAA pathophysiology in humans, animal models, and cultured cells, with an emphasis on sex differences and sex steroid hormone signaling.

Sex Differences in Learning Abilities and Disabilities.

ERIC Educational Resources Information Center

Nass, Ruth D.

1993-01-01

This review of the male preponderance in the prevalence of learning disabilities examines such factors as gender-related etiology differences and learning style differences; complications of pregnancy and infancy; effects of male hormones on the nervous system; and sex differences in maturity rates. (JDD)

Sex differences in the genetic and environmental influences on childhood conduct disorder and adult antisocial behavior.

PubMed

Meier, Madeline H; Slutske, Wendy S; Heath, Andrew C; Martin, Nicholas G

2011-05-01

Sex differences in the genetic and environmental influences on childhood conduct disorder and adult antisocial behavior were examined in a large community sample of 6,383 adult male, female, and opposite-sex twins. Retrospective reports of childhood conduct disorder (prior to 18 years of age) were obtained when participants were approximately 30 years old, and lifetime reports of adult antisocial behavior (antisocial behavior after 17 years of age) were obtained 8 years later. Results revealed that either the genetic or the shared environmental factors influencing childhood conduct disorder differed for males and females (i.e., a qualitative sex difference), but by adulthood, these sex-specific influences on antisocial behavior were no longer apparent. Further, genetic and environmental influences accounted for proportionally the same amount of variance in antisocial behavior for males and females in childhood and adulthood (i.e., there were no quantitative sex differences). Additionally, the stability of antisocial behavior from childhood to adulthood was slightly greater for males than females. Though familial factors accounted for more of the stability of antisocial behavior for males than females, genetic factors accounted for the majority of the covariation between childhood conduct disorder and adult antisocial behavior for both sexes. The genetic influences on adult antisocial behavior overlapped completely with the genetic influences on childhood conduct disorder for both males and females. Implications for future twin and molecular genetic studies are discussed.

Sex Differences in the Genetic and Environmental Influences on Childhood Conduct Disorder and Adult Antisocial Behavior

PubMed Central

Meier, Madeline H.; Slutske, Wendy S.; Heath, Andrew C.; Martin, Nicholas G.

2011-01-01

Sex differences in the genetic and environmental influences on childhood conduct disorder and adult antisocial behavior were examined in a large community sample of 6,383 adult male, female, and opposite-sex twins. Retrospective reports of childhood conduct disorder (prior to age 18) were obtained when participants were approximately 30 years old, and lifetime reports of adult antisocial behavior (antisocial behavior after age 17) were obtained eight years later. Results revealed that either the genetic or shared environmental factors influencing childhood conduct disorder differed for males and females (i.e., a qualitative sex difference), but by adulthood, these sex-specific influences on antisocial behavior were no longer apparent. Further, genetic and environmental influences accounted for proportionally the same amount of variance in antisocial behavior for males and females in childhood and adulthood (i.e., no quantitative sex differences). Additionally, the stability of antisocial behavior from childhood to adulthood was slightly greater for males than females. Though familial factors accounted for more of the stability of antisocial behavior for males than females, genetic factors accounted for the majority of the covariation between childhood conduct disorder and adult antisocial behavior for both sexes. The genetic influences on adult antisocial behavior overlapped completely with the genetic influences on childhood conduct disorder for both males and females. Implications for future twin and molecular genetic studies are discussed. PMID:21319923

Age difference asymmetry and a two-sex perspective.

PubMed

Ni Bhrolchain, M

1992-01-01

Age differences in marriage are examined using data from the Marriage and Divorce Statistics, Series FM2, 1966-87, in England and Wales. Specifically, there is a description of differentials in the spousal age gap by sex and marital status of the partner, trends in the age differences between spouses, the components of change in age differences, i.e., changing age at marriage, and changes in partner's marital status. Data were unavailable to answer whether or not changes in opportunity or constraint (shifts in age/sex distribution) or changing preferences in relation to age differences or both affected the shifts, but plausible interpretations are provided. The difference in ages is evident in the pattern of mean age difference in 1987 for single brides (3.0 years) and the mean gap for bachelors (1.6 years). These figures are still different from the 2.1-year gap in the marriages of 2 single partners or the 2.6-year gap for all marriages. The mean age of 1st marriages is 2.2 for both sexes, 1.6 for men and 3.0 for women. for 2nd and later marriages the pattern is reversed, where divorced women remarry to men averaging 1.7 years older while divorced men remarry a woman 5.3 years younger. The gaps among the widowed are 1.9 years for women and 6.7 years for men. The reasons for the differentials are that not all single men marry single women and the reverse, and that age differences depend on sex, marriage order for both sexes, and marital status of the partner. The longitudinal pattern of age differences being larger in remarriages than in 1st marriages is exhibited for male remarriages only; for women in remarriages the age difference is shortened from 3.0 years to 1.7 years. In comparing time trends, 1) the mean age gap is consistently larger in women's than in men's 1st marriages with a larger gap appearing closer to the present; 2) the age differences have fluctuated over time; 3) the gap in men's and women's marriages were similar up to 1970 and, between 1970

Absenteeism, Burnout and Symptomatology of Teacher Stress: Sex Differences

ERIC Educational Resources Information Center

Bermejo-Toro, Laura; Prieto-Ursúa, María

2014-01-01

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…

Drivers of protogynous sex change differ across spatial scales.

PubMed

Taylor, Brett M

2014-01-22

The influence of social demography on sex change schedules in protogynous reef fishes is well established, yet effects across spatial scales (in particular, the magnitude of natural variation relative to size-selective fishing effects) are poorly understood. Here, I examine variation in timing of sex change for exploited parrotfishes across a range of environmental, anthropogenic and geographical factors. Results were highly dependent on spatial scale. Fishing pressure was the most influential factor determining length at sex change at the within-island scale where a wide range of anthropogenic pressure existed. Sex transition occurred at smaller sizes where fishing pressure was high. Among islands, however, differences were overwhelmingly predicted by reefal-scale structural features, a pattern evident for all species examined. For the most abundant species, Chlorurus spilurus, length at sex change increased at higher overall densities and greater female-to-male sex ratios at all islands except where targeted by fishermen; here the trend was reversed. This implies differing selective pressures on adult individuals can significantly alter sex change dynamics, highlighting the importance of social structure, demography and the selective forces structuring populations. Considerable life-history responses to exploitation were observed, but results suggest potential fishing effects on demography may be obscured by natural variation at biogeographic scales.

Sex differences in physician salary in U.S. public medical schools

PubMed Central

Jena, Anupam B.; Olenski, Andrew R.; Blumenthal, Daniel M.

2017-01-01

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

Spatial ability in secondary school students: intra-sex differences based on self-selection for physical education.

PubMed

Tlauka, Michael; Williams, Jennifer; Williamson, Paul

2008-08-01

Past research has demonstrated consistent sex differences with men typically outperforming women on tests of spatial ability. However, less is known about intra-sex effects. In the present study, two groups of female students (physical education and non-physical education secondary students) and two corresponding groups of male students explored a large-scale virtual shopping centre. In a battery of tasks, spatial knowledge of the shopping centre as well as mental rotation ability were tested. Additional variables considered were circulating testosterone levels, the ratio of 2D:4D digit length, and computer experience. The results revealed both sex and intra-sex differences in spatial ability. Variables related to virtual navigation and computer ability and experience were found to be the most powerful predictors of group membership. Our results suggest that in female and male secondary students, participation in physical education and spatial skill are related.

Sex Differences in the Longitudinal Prediction of Adult Personality.

ERIC Educational Resources Information Center

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…

Sex differences in cryptogenic stroke with patent foramen ovale.

PubMed

Nedeltchev, Krassen; Wiedmer, Sebastian; Schwerzmann, Markus; Windecker, Stephan; Haefeli, Tobias; Meier, Bernhard; Mattle, Heinrich P; Arnold, Marcel

2008-09-01

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.

Sex Differences in Cerebral Laterality of Language and Visuospatial Processing

ERIC Educational Resources Information Center

Clements, A. M.; Rimrodt, S. L.; Abel, J. R.; Blankner, J. G.; Mostofsky, S. H.; Pekar, J. J.; Denckla, M. B.; Cutting, L. E.

2006-01-01

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…

Sex differences in stress responses: a critical role for corticotropin-releasing factor.

PubMed

Bangasser, Debra A; Wiersielis, Kimberly R

2018-03-01

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.

Infants' preferences for toys, colors, and shapes: sex differences and similarities.

PubMed

Jadva, Vasanti; Hines, Melissa; Golombok, Susan

2010-12-01

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.

Neonatal testosterone partially organizes sex differences in stress-induced emotionality in mice

PubMed Central

Seney, Marianne L.; Walsh, Christopher; Stolakis, Ryan; Sibille, Etienne

2012-01-01

Major depressive disorder (MDD) is a debilitating disorder of altered mood regulation. Despite well established sex differences in MDD prevalence, the mechanism underlying the increased female vulnerability remains unknown. Although evidence suggests an influence of adult circulating hormone levels on mood (i.e. activational effects of hormones), MDD prevalence is consistently higher in women across life stages (and therefore hormonal states), suggesting that additional underlying structural or biological differences place women at higher risk. Studies in human subjects and in rodent models suggest a developmental origin for mood disorders, and interestingly, a developmental process also establishes sex differences in the brain. Hence, based on these parallel developmental trajectories, we hypothesized that a proportion of the female higher vulnerability to MDD may originate from the differential organization of mood regulatory neural networks early in life (i.e. organizational effects of hormones). To test this hypothesis in a rodent system, we took advantage of a well-established technique used in the field of sexual differentiation (neonatal injection with testosterone) to masculinize sexually dimorphic brain regions in female mice. We then investigated adult behavioral consequences relating to emotionality by comparing neonatal testosterone-treated females to normal males and females. Under baseline/trait conditions, neonatal testosterone treatment of female mice did not influence adult emotionality, but masculinized adult locomotor activity, as revealed by the activational actions of hormones. Conversely, the increased vulnerability of female mice to develop high emotionality following unpredictable chronic mild stress (UCMS) was partially masculinized by neonatal testosterone exposure, with no effect on post-UCMS locomotion. The elevated female UCMS-induced vulnerability did not differ between adult hormone treated groups. These results demonstrate that sex

Sex Differences in Memory for Sexually-Relevant Information

PubMed Central

McCall, Katie M.; Rellini, Alessandra H.; Seal, Brooke N.

2010-01-01

The present study was conducted in an attempt to examine potential differences between men and women in memory for sexually relevant information. A total of 77 undergraduate students (31 men, 46 women) read a sexual story and completed memory tasks in response to the story. Based on previous research, we hypothesized that differences would exist between men and women for different types of sexual information and we hoped to understand whether specific variables (sexual experiences, sexual functioning, and reactions to the sexual story) could explain such differences. Men were more likely to remember erotic or explicit details of the story, whereas women were more likely to remember love and emotional bonding details of the story. Additionally, women were more likely to recall information referencing the characters in the story. Results from regression analyses indicated that sexual desire and satisfaction were related to differences in recall and recognition of the love and emotional bonding aspects of the story, and that frequency of sexual intercourse was related to differences in the recall of erotic or explicit details of the story. The significant results obtained in this study correspond to previously established sex differences in memory for sexual information. PMID:17186127

Sex Differences in Panic-Relevant Responding to a 10% Carbon Dioxide-Enriched Air Biological Challenge

PubMed Central

Nillni, Yael I.; Berenz, Erin C.; Rohan, Kelly J.; Zvolensky, Michael J.

2011-01-01

The current study examined sex differences in psychological (i.e., self-reported anxiety, panic symptoms, and avoidance) and physiological (i.e., heart rate and skin conductance level) response to, and recovery from, a laboratory biological challenge. Participants were a community-recruited sample of 128 adults (63.3% women; Mage = 23.2 years, SD = 8.9) who underwent a 4-minute 10% CO2-enriched air biological challenge. As predicted, women reported more severe physical panic symptoms and avoidance (i.e., less willingness to participate in another challenge) and demonstrated increased heart rate as compared to men above and beyond the variance accounted for by other theoretically-relevant variables (recent panic attack history, neuroticism, and anxiety sensitivity). Additionally, women demonstrated a faster rate of recovery with respect to heart rate compared to men. These results are in line with literature documenting sex-specific differences in panic psychopathology, and results are discussed in the context of possible mechanisms underlying sex differences in panic vulnerability. PMID:22115836

A systematic literature review of sex differences in childhood language and brain development.

PubMed

Etchell, Andrew; Adhikari, Aditi; Weinberg, Lauren S; Choo, Ai Leen; Garnett, Emily O; Chow, Ho Ming; Chang, Soo-Eun

2018-06-01

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.

Sex-different hepaticglycogen content and glucose output in rats

PubMed Central

2010-01-01

Background Genes involved in hepatic metabolism have a sex-different expression in rodents. To test whether male and female rat livers differ regarding lipid and carbohydrate metabolism, whole-genome transcript profiles were generated and these were complemented by measurements of hepatic lipid and glycogen content, fatty acid (FA) oxidation rates and hepatic glucose output (HGO). The latter was determined in perfusates from in situ perfusion of male and female rat livers. These perfusates were also analysed using nuclear magnetic resonance (NMR) spectroscopy to identify putative sex-differences in other liver-derived metabolites. Effects of insulin were monitored by analysis of Akt-phosphorylation, gene expression and HGO after s.c. insulin injections. Results Out of approximately 3 500 gene products being detected in liver, 11% were significantly higher in females, and 11% were higher in males. Many transcripts for the production of triglycerides (TG), cholesterol and VLDL particles were female-predominant, whereas genes for FA oxidation, gluconeogenesis and glycogen synthesis were male-predominant. Sex-differences in mRNA levels related to metabolism were more pronounced during mild starvation (12 h fasting), as compared to the postabsorptive state (4 h fasting). No sex-differences were observed regarding hepatic TG content, FA oxidation rates or blood levels of ketone bodies or glucose. However, males had higher hepatic glycogen content and higher HGO, as well as higher ratios of insulin to glucagon levels. Based on NMR spectroscopy, liver-derived lactate was also higher in males. HGO was inhibited by insulin in parallel with increased phosphorylation of Akt, without any sex-differences in insulin sensitivity. However, the degree of Thr172-phosphorylated AMP kinase (AMPK) was higher in females, indicating a higher degree of AMPK-dependent actions. Conclusions Taken together, males had higher ratios of insulin to glucagon levels, higher levels of glycogen, lower

Paraphilic Interests: An Examination of Sex Differences in a Nonclinical Sample.

PubMed

Dawson, Samantha J; Bannerman, Brittany A; Lalumière, Martin L

2016-02-01

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.

Sex-related differences in amygdala functional connectivity during resting conditions.

PubMed

Kilpatrick, L A; Zald, D H; Pardo, J V; Cahill, L F

2006-04-01

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.

Review of Research--Sex Differences in Intellectual Functioning: Myth or Reality.

ERIC Educational Resources Information Center

Glickman, Judith R.

Sex difference research has been plagued with a myriad of problems,. Specifically, intelligence testing, if dependent on measurement of spatial or verbal proficiency, may not be an accurate indicator of native ability. Similarly, infrequent replication of studies, studies that only include subjects of one sex yet imply sex differences, and poor…

Genetic regulation of sex differences in songbirds and lizards.

PubMed

Wade, Juli

2016-02-19

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. © 2016 The Author(s).

Genetic regulation of sex differences in songbirds and lizards

PubMed Central

Wade, Juli

2016-01-01

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

Sex differences in gingivitis relate to interaction of oral health behaviors in young people.

PubMed

Furuta, Michiko; Ekuni, Daisuke; Irie, Koichiro; Azuma, Tetsuji; Tomofuji, Takaaki; Ogura, Toshio; Morita, Manabu

2011-04-01

Although many epidemiologic surveys have shown that gingivitis is more prevalent in males than in females, few studies have clearly explained what causes this difference. The objective of the present study is to explain the sex difference in gingivitis based on the interaction between oral health behaviors and related factors, such as knowledge, attitude, and lifestyle, in young people. The study was comprised of 838 subjects (440 males and 398 females), aged 18 and 19 years. Gingivitis was assessed by the percentage of bleeding on probing (%BOP). Additional information was collected regarding oral hygiene status, oral health behaviors, and related factors. Structural equation modeling was used to test pathways from these factors to %BOP. Multiple-group modeling was also conducted to test for sex differences. Females had greater knowledge, a more positive attitude, a healthier lifestyle, and higher level of oral health behaviors than males. There were significant differences in the paths (i.e., from lifestyle, knowledge, and attitude to %BOP) through oral health behaviors and oral health status. Sex-based differences in gingivitis in young people can be explained by oral health behaviors and hygiene status, which are influenced by lifestyle, knowledge, and attitude. To prevent gingivitis, different approaches to males and females may be useful.

Sex differences in adolescent white matter architecture.

PubMed

Bava, Sunita; Boucquey, Veronique; Goldenberg, Diane; Thayer, Rachel E; Ward, Megan; Jacobus, Joanna; Tapert, Susan F

2011-02-23

Sex-specific trajectories in white matter development during adolescence may help explain cognitive and behavioral divergences between males and females. Knowledge of sex differences in typically developing adolescents can provide a basis for interpreting sexual dimorphisms in abilities and actions. We examined 58 healthy adolescents (12-14years of age) with diffusion tensor imaging (DTI). Diffusion parameters fractional anisotropy (FA), and mean (MD), radial (RD), and axial diffusivities (AD) were subjected to whole-brain voxel-wise group comparisons using tract-based spatial statistics. Sex differences in white matter microstructure were examined in relation to pubertal development. Early adolescent females (n=29) evidenced higher FA in the right superior corona radiata, higher FA and AD in bilateral corticospinal tracts (≥164μl, p<.01), and lower MD in the right inferior longitudinal fasciculus (ILF) and left forceps major (≥164μl, p<.01) than age-matched males (n=29). Males did not show any areas of higher FA or lower MD than females, but had higher AD in the right superior longitudinal fasciculus, ILF, and forceps minor (≥ 164μl, p<.01). Pubertal stage did not account for sex disparities. In early adolescence, females' motor tracts may reflect widespread changes, while males may undergo relatively more microstructural change in projection and association fibers. Copyright © 2010 Elsevier B.V. All rights reserved.

Sex Differences in Brain-Derived Neurotrophic Factor Signaling and Functions

PubMed Central

Chan, Chi Bun; Ye, Keqiang

2016-01-01

Brain derived neurotrophic factor (BDNF) is a member of the neurotrophin family that plays a critical role in numerous neuronal activities. Recent studies report that some functions or action mechanisms of BDNF vary in a sex-dependent manner. In particular, BDNF content in some brain parts and the tendency of developing BDNF-deficient-related diseases like depression is higher in female animals. With the support of other relevant studies, it is suggested that sex hormones or steroids can modulate the activities of BDNF, which may account for its functional discrepancy in different sexes. Indeed, the cross-talk between BDNF and sex steroids has been detected for decades and some sex steroids like estrogen have a positive regulatory effect to BDNF expression and signaling. Thus, the sex of animal models used is critical when studying the functions of BDNF in vivo. In this review, we will summarize our current findings on the difference in expression, signaling, and functions of BDNF between sexes. We will also discuss the potential mechanisms in mediating these differential responses with a specific emphasis on sex steroids. By presenting and discussing these findings, we encourage taking sex influences into consideration when designing experiments, interpreting results and drawing conclusions. PMID:27870419

Sex differences in jealousy: a population-based twin study in Sweden.

PubMed

Walum, Hasse; Larsson, Henrik; Westberg, Lars; Lichtenstein, Paul; Magnusson, Patrik K E

2013-10-01

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.

Sex-related differences in the wheel-running activity of mice decline with increasing age.

PubMed

Bartling, Babett; Al-Robaiy, Samiya; Lehnich, Holger; Binder, Leonore; Hiebl, Bernhard; Simm, Andreas

2017-01-01

Laboratory mice of both sexes having free access to running wheels are commonly used to study mechanisms underlying the beneficial effects of physical exercise on health and aging in human. However, comparative wheel-running activity profiles of male and female mice for a long period of time in which increasing age plays an additional role are unknown. Therefore, we permanently recorded the wheel-running activity (i.e., total distance, median velocity, time of breaks) of female and male mice until 9months of age. Our records indicated higher wheel-running distances for females than males which were highest in 2-month-old mice. This was mainly reached by higher running velocities of the females and not by longer running times. However, the sex-related differences declined in parallel to the age-associated reduction in wheel-running activities. Female mice also showed more variances between the weekly running distances than males, which were recorded most often for females being 4-6months old but not older. Additional records of 24-month-old mice of both sexes indicated highly reduced wheel-running activities at old age. Surprisingly, this reduction at old age resulted mainly from lower running velocities and not from shorter running times. Old mice also differed in their course of night activity which peaked later compared to younger mice. In summary, we demonstrated the influence of sex on the age-dependent activity profile of mice which is somewhat contrasting to humans, and this has to be considered when transferring exercise-mediated mechanism from mouse to human. Copyright © 2016. Published by Elsevier Inc.

Sex differences in visual attention to erotic and non-erotic stimuli.

PubMed

Lykins, Amy D; Meana, Marta; Strauss, Gregory P

2008-04-01

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.

Sex differences in neural activation to facial expressions denoting contempt and disgust.

PubMed

Aleman, André; Swart, Marte

2008-01-01

The facial expression of contempt has been regarded to communicate feelings of moral superiority. Contempt is an emotion that is closely related to disgust, but in contrast to disgust, contempt is inherently interpersonal and hierarchical. The aim of this study was twofold. First, to investigate the hypothesis of preferential amygdala responses to contempt expressions versus disgust. Second, to investigate whether, at a neural level, men would respond stronger to biological signals of interpersonal superiority (e.g., contempt) than women. We performed an experiment using functional magnetic resonance imaging (fMRI), in which participants watched facial expressions of contempt and disgust in addition to neutral expressions. The faces were presented as distractors in an oddball task in which participants had to react to one target face. Facial expressions of contempt and disgust activated a network of brain regions, including prefrontal areas (superior, middle and medial prefrontal gyrus), anterior cingulate, insula, amygdala, parietal cortex, fusiform gyrus, occipital cortex, putamen and thalamus. Contemptuous faces did not elicit stronger amygdala activation than did disgusted expressions. To limit the number of statistical comparisons, we confined our analyses of sex differences to the frontal and temporal lobes. Men displayed stronger brain activation than women to facial expressions of contempt in the medial frontal gyrus, inferior frontal gyrus, and superior temporal gyrus. Conversely, women showed stronger neural responses than men to facial expressions of disgust. In addition, the effect of stimulus sex differed for men versus women. Specifically, women showed stronger responses to male contemptuous faces (as compared to female expressions), in the insula and middle frontal gyrus. Contempt has been conceptualized as signaling perceived moral violations of social hierarchy, whereas disgust would signal violations of physical purity. Thus, our results suggest a

Sex Differences in Neural Activation to Facial Expressions Denoting Contempt and Disgust

PubMed Central

Aleman, André; Swart, Marte

2008-01-01

The facial expression of contempt has been regarded to communicate feelings of moral superiority. Contempt is an emotion that is closely related to disgust, but in contrast to disgust, contempt is inherently interpersonal and hierarchical. The aim of this study was twofold. First, to investigate the hypothesis of preferential amygdala responses to contempt expressions versus disgust. Second, to investigate whether, at a neural level, men would respond stronger to biological signals of interpersonal superiority (e.g., contempt) than women. We performed an experiment using functional magnetic resonance imaging (fMRI), in which participants watched facial expressions of contempt and disgust in addition to neutral expressions. The faces were presented as distractors in an oddball task in which participants had to react to one target face. Facial expressions of contempt and disgust activated a network of brain regions, including prefrontal areas (superior, middle and medial prefrontal gyrus), anterior cingulate, insula, amygdala, parietal cortex, fusiform gyrus, occipital cortex, putamen and thalamus. Contemptuous faces did not elicit stronger amygdala activation than did disgusted expressions. To limit the number of statistical comparisons, we confined our analyses of sex differences to the frontal and temporal lobes. Men displayed stronger brain activation than women to facial expressions of contempt in the medial frontal gyrus, inferior frontal gyrus, and superior temporal gyrus. Conversely, women showed stronger neural responses than men to facial expressions of disgust. In addition, the effect of stimulus sex differed for men versus women. Specifically, women showed stronger responses to male contemptuous faces (as compared to female expressions), in the insula and middle frontal gyrus. Contempt has been conceptualized as signaling perceived moral violations of social hierarchy, whereas disgust would signal violations of physical purity. Thus, our results suggest a

Early sex differences in weighting geometric cues.

PubMed

Lourenco, Stella F; Addy, Dede; Huttenlocher, Janellen; Fabian, Lydia

2011-11-01

When geometric and non-geometric information are both available for specifying location, men have been shown to rely more heavily on geometry compared to women. To shed insight on the nature and developmental origins of this sex difference, we examined how 18- to 24-month-olds represented the geometry of a surrounding (rectangular) space when direct non-geometric information (i.e. a beacon) was also available for localizing a hidden object. Children were tested on a disorientation task with multiple phases. Across experiments, boys relied more heavily than girls on geometry to guide localization, as indicated by their errors during the initial phase of the task, and by their search choices following transformations that left only geometry available, or that, under limited conditions, created a conflict between beacon and geometry. Analyses of search times suggested that girls, like boys, had encoded geometry, and testing in a square space ruled out explanations concerned with motivational and methodological variables. Taken together, the findings provide evidence for an early sex difference in the weighting of geometry. This sex difference, we suggest, reflects subtle variation in how boys and girls approach the problem of combining multiple sources of location information. 2011 Blackwell Publishing Ltd.

Females scan more than males: a potential mechanism for sex differences in recognition memory.

PubMed

Heisz, Jennifer J; Pottruff, Molly M; Shore, David I

2013-07-01

Recognition-memory tests reveal individual differences in episodic memory; however, by themselves, these tests provide little information regarding the stage (or stages) in memory processing at which differences are manifested. We used eye-tracking technology, together with a recognition paradigm, to achieve a more detailed analysis of visual processing during encoding and retrieval. Although this approach may be useful for assessing differences in memory across many different populations, we focused on sex differences in face memory. Females outperformed males on recognition-memory tests, and this advantage was directly related to females' scanning behavior at encoding. Moreover, additional exposures to the faces reduced sex differences in face recognition, which suggests that males may be able to improve their recognition memory by extracting more information at encoding through increased scanning. A strategy of increased scanning at encoding may prove to be a simple way to enhance memory performance in other populations with memory impairment.

Sex differences in the neural representation of pain unpleasantness.

PubMed

Girard-Tremblay, Lydia; Auclair, Vincent; Daigle, Kathya; Léonard, Guillaume; Whittingstall, Kevin; Goffaux, Philippe

2014-08-01

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.

Sex differences in ischemic stroke sensitivity are influenced by gonadal hormones, not by sex chromosome complement.

PubMed

Manwani, Bharti; Bentivegna, Kathryn; Benashski, Sharon E; Venna, Venugopal Reddy; Xu, Yan; Arnold, Arthur P; McCullough, Louise D

2015-02-01

Epidemiologic studies have shown sex differences in ischemic stroke. The four core genotype (FCG) mouse model, in which the testes determining gene, Sry, has been moved from Y chromosome to an autosome, was used to dissociate the effects of sex hormones from sex chromosome in ischemic stroke outcome. Middle cerebral artery occlusion (MCAO) in gonad intact FCG mice revealed that gonadal males (XXM and XYM) had significantly higher infarct volumes as compared with gonadal females (XXF and XYF). Serum testosterone levels were equivalent in adult XXM and XYM, as was serum estrogen in XXF and XYF mice. To remove the effects of gonadal hormones, gonadectomized FCG mice were subjected to MCAO. Gonadectomy significantly increased infarct volumes in females, while no change was seen in gonadectomized males, indicating that estrogen loss increases ischemic sensitivity. Estradiol supplementation in gonadectomized FCG mice rescued this phenotype. Interestingly, FCG male mice were less sensitive to effects of hormones. This may be due to enhanced expression of the transgene Sry in brains of FCG male mice. Sex differences in ischemic stroke sensitivity appear to be shaped by organizational and activational effects of sex hormones, rather than sex chromosomal complement.

The Odour of Sex: Sex-Related Differences in Volatile Compound Composition among Barn Swallow Eggs Carrying Embryos of Either Sex

PubMed Central

Costanzo, Alessandra; Panseri, Sara; Giorgi, Annamaria; Romano, Andrea; Caprioli, Manuela; Saino, Nicola

2016-01-01

Avian communication has been traditionally believed to be mainly mediated by visual and auditory channels. However, an increasing number of studies are disclosing the role of olfaction in the interaction of birds with their social environment and with other species, as well as in other behaviors such as nest recognition, food location and navigation. Olfaction has also been suggested to play a role in parent-offspring communication not only in the post- but also in the pre-hatching period. Volatile compounds produced during embryogenesis and passively released through the eggshell pores may indeed represent the only cue at parents’ disposal to assess offspring quality, including the sex composition of their clutch before hatching. In turn, sex identification before hatching may mediate adaptive strategies of allocation to either sex. In the present study, we analyzed odour composition of barn swallow eggs incubated in their nest in order to identify any sex-related differences in volatile compounds emitted. For the first time in any bird species, we also investigated whether odour composition is associated with relatedness. The evidence of differences in odour composition among eggs containing embryos of either sex indicates that parents have a cue to identify their brood sex composition even before hatching which can be used to modulate their behavior accordingly. Moreover, odour similarity within nests may represent the prerequisite for kin recognition in this species. PMID:27851741

Sex difference in PCB concentrations of a catostomid fish

USGS Publications Warehouse

Madenjian, Charles P.; Stevens, Andrew L.; Stapanian, Martin A.; Batterman, Stuart A.; Chernyak, Sergei M.; Menczer, Jordan E.; McIntyre, Peter B.

2017-01-01

Unraveling the complexities associated with the relative differences in contaminant concentrations between the sexes of mature fish may provide insights into important behavioral and physiological differences between the sexes of not just fish but higher vertebrates as well. Whole-fish polychlorinated biphenyl (PCB) concentrations were determined in 25 mature female white suckers (Catostomus commersoni) and 26 mature male white suckers caught during their spawning run in the Kewaunee River, a tributary to Lake Michigan. Total length and weight were measured for each fish, and age of each fish was estimated from thin-sectioned otoliths. PCB concentration significantly increased with increasing total length, weight, and age. Consequently, three analysis of covariance (ANCOVA) models were fitted to the data to assess the effect of sex on white sucker PCB concentration. Based on model averaging, estimates of mean PCB concentrations in female and male white suckers were 185 and 219 ng/g, respectively. Thus, males were 18% greater in PCB concentration than females. We conclude that this difference between the sexes was most likely mainly driven by a higher rate of energy expenditure in males compared with females. Greater energy expenditure, owing to greater swimming activity and a higher resting metabolic rate, resulted in a higher rate of food consumption, which in turn led to a greater rate of PCB accumulation. Higher whole-fish PCB concentration in males compared with females has now been shown in nine different fish species. Our study represented the first documentation of this type of sex difference in a catostomid fish.

The clinician perspective on sex differences in autism spectrum disorders.

PubMed

Jamison, Rene; Bishop, Somer L; Huerta, Marisela; Halladay, Alycia K

2017-08-01

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, making it challenging to discern if, how, and at what point in development females with autism spectrum disorder actually exhibit a different behavioral presentation than males. The purpose of this study was to gather impressions from a large group of clinicians to isolate specific areas for future study of sex differences. Clinicians were surveyed about their opinions and perceptions of symptom severity in females, as compared to males, at different points during development. They were also asked to provide open-ended responses about female symptom presentation. Consistent with previous literature, clinicians noted more sex-related differences in restricted and repetitive behaviors and fewer differences for social communication features. Differences were most commonly observed in school age and adolescence, suggesting this time period as a critical and particularly vulnerable window for females with autism spectrum disorder. The results are discussed in the context of other male/female differences across development so that more targeted investigations of autism spectrum disorder sex differences across development.

Sex Differences in the Effect of Puberty on Hippocampal Morphology

PubMed Central

Satterthwaite, Theodore D.; Vandekar, Simon; Wolf, Daniel H.; Ruparel, Kosha; Roalf, David R.; Jackson, Chad; Elliott, Mark A.; Bilker, Warren B.; Calkins, Monica E.; Prabhakaran, Karthik; Davatzikos, Christos; Hakonarson, Hakon; Gur, Raquel E.; Gur, Ruben C.

2014-01-01

Objective Puberty is the defining process of adolescence, and is accompanied by divergent trajectories of behavior and cognition for males and females. Here we examine whether sex differences exist in the effect of puberty on the morphology of the hippocampus and amygdala. Method T1-weighted structural neuroimaging was performed in a sample of 524 pre- or postpubertal adolescents ages 10–22. Hippocampal and amygdala volume and shape were quantified using FSL’s FIRST procedure and scaled by intracranial volume. The effects on regional volume of age, sex, puberty, and their interactions were examined using linear regression. Postpubertal sex differences were examined using a vertex analysis. Results Prepubertal males and females had similar hippocampal volumes, whereas postpubertal females had significantly larger bilateral hippocampi, resulting in a significant puberty-by-sex interaction even when controlling for age and age-by-sex. This effect was regionally specific and was not apparent in the amygdala. Vertex analysis revealed that postpubertal differences were most prominent in the lateral aspect of the hippocampus bilaterally, corresponding to the CA1 subfield. Conclusions These results establish that there are regionally specific sex differences in the effect of puberty on the hippocampus. These findings are relevant for the understanding of psychiatric disorders that have both hippocampal dysfunction and prominent gender disparities during adolescence. PMID:24565361

Different patterns of puberty effect in neural oscillation to negative stimuli: sex differences.

PubMed

Yuan, Jiajin; Ju, Enxia; Yang, Jiemin; Chen, Xuhai; Li, Hong

2014-12-01

The present study investigated the impact of puberty on sex differences in neural sensitivity to negative stimuli. Event-related oscillation technique was used. Because girls are more vulnerable to affective disturbances than boys during adolescence, it was hypothesized that puberty exerts different influences on neural sensitivity to negative stimuli in boys and girls. EEGs were recorded for highly negative (HN), mildly negative (MN) and neutral pictures, when boys and girls distinct in pubertal status performed a non-emotional distracting task. No emotion effect and its interaction with sex and puberty were observed in response latencies. However, puberty influenced the gamma-band oscillation effect for negative stimuli differently for boys and girls: Pre-pubertal boys showed a significant emotion effect for HN stimuli, whose size was decreased in pubertal boys. By contrast, there was a significant emotion effect for HN stimuli in pubertal girls but not in pre-pubertal girls. On the other hand, the size of the emotion effect for HN stimuli was similar for pre-pubertal boys and girls; while this effect was significantly more pronounced in pubertal girls compared to pubertal boys. Additionally, the size of the emotion effect in gamma oscillations decreased as a function of pubertal development during both HN and MN stimulation in boys. For girls, the emotion effect in gamma oscillations increased with pubertal development during HN stimulation. Thus, puberty is associated with reduced neural sensitivity in boys but increased sensitivity in girls, in reaction to negative stimuli. The implications of these results for the psychopathology during adolescence were discussed.

Genetic Mechanisms Leading to Sex Differences Across Common Diseases and Anthropometric Traits.

PubMed

Traglia, Michela; Bseiso, Dina; Gusev, Alexander; Adviento, Brigid; Park, Daniel S; Mefford, Joel A; Zaitlen, Noah; Weiss, Lauren A

2017-02-01

Common diseases often show sex differences in prevalence, onset, symptomology, treatment, or prognosis. Although studies have been performed to evaluate sex differences at specific SNP associations, this work aims to comprehensively survey a number of complex heritable diseases and anthropometric traits. Potential genetically encoded sex differences we investigated include differential genetic liability thresholds or distributions, gene-sex interaction at autosomal loci, major contribution of the X-chromosome, or gene-environment interactions reflected in genes responsive to androgens or estrogens. Finally, we tested the overlap between sex-differential association with anthropometric traits and disease risk. We utilized complementary approaches of assessing GWAS association enrichment and SNP-based heritability estimation to explore explicit sex differences, as well as enrichment in sex-implicated functional categories. We do not find consistent increased genetic load in the lower-prevalence sex, or a disproportionate role for the X-chromosome in disease risk, despite sex-heterogeneity on the X for several traits. We find that all anthropometric traits show less than complete correlation between the genetic contribution to males and females, and find a convincing example of autosome-wide genome-sex interaction in multiple sclerosis (P = 1 × 10 -9 ). We also find some evidence for hormone-responsive gene enrichment, and striking evidence of the contribution of sex-differential anthropometric associations to common disease risk, implying that general mechanisms of sexual dimorphism determining secondary sex characteristics have shared effects on disease risk. Copyright © 2017 by the Genetics Society of America.

Genetic Mechanisms Leading to Sex Differences Across Common Diseases and Anthropometric Traits

PubMed Central

Traglia, Michela; Bseiso, Dina; Gusev, Alexander; Adviento, Brigid; Park, Daniel S.; Mefford, Joel A.; Zaitlen, Noah; Weiss, Lauren A.

2017-01-01

Common diseases often show sex differences in prevalence, onset, symptomology, treatment, or prognosis. Although studies have been performed to evaluate sex differences at specific SNP associations, this work aims to comprehensively survey a number of complex heritable diseases and anthropometric traits. Potential genetically encoded sex differences we investigated include differential genetic liability thresholds or distributions, gene–sex interaction at autosomal loci, major contribution of the X-chromosome, or gene–environment interactions reflected in genes responsive to androgens or estrogens. Finally, we tested the overlap between sex-differential association with anthropometric traits and disease risk. We utilized complementary approaches of assessing GWAS association enrichment and SNP-based heritability estimation to explore explicit sex differences, as well as enrichment in sex-implicated functional categories. We do not find consistent increased genetic load in the lower-prevalence sex, or a disproportionate role for the X-chromosome in disease risk, despite sex-heterogeneity on the X for several traits. We find that all anthropometric traits show less than complete correlation between the genetic contribution to males and females, and find a convincing example of autosome-wide genome-sex interaction in multiple sclerosis (P = 1 × 10−9). We also find some evidence for hormone-responsive gene enrichment, and striking evidence of the contribution of sex-differential anthropometric associations to common disease risk, implying that general mechanisms of sexual dimorphism determining secondary sex characteristics have shared effects on disease risk. PMID:27974502

Sex Differences in Intelligence and Brain Size: A Developmental Theory.

ERIC Educational Resources Information Center

Lynn, Richard

1999-01-01

Proposes a developmental theory of sex differences in intelligence that states that the faster maturation and brain size growth in girls up to age 15 compensates for their smaller brain size so that sex differences in intelligence are very small. Discusses evidence that supports this theory. (SLD)

Sex Differences in Physician Salary in US Public Medical Schools.

PubMed

Jena, Anupam B; Olenski, Andrew R; Blumenthal, Daniel M

2016-09-01

Limited evidence exists on salary differences between male and female academic physicians, largely owing 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. To analyze sex differences in earnings among US academic physicians. Freedom of Information laws mandate release of salary information of public university employees in several states. In 12 states with salary information published online, salary data were extracted on 10 241 academic physicians at 24 public medical schools. These data were linked to a unique physician database with detailed information on sex, age, years of experience, faculty rank, specialty, scientific authorship, National Institutes of Health funding, clinical trial participation, and Medicare reimbursements (proxy for clinical revenue). Sex differences in salary were estimated after adjusting for these factors. Physician sex. Annual salary. Among 10 241 physicians, female physicians (n = 3549) had lower mean (SD) unadjusted salaries than male physicians ($206 641 [$88 238] vs $257 957 [$137 202]; absolute difference, $51 315 [95% CI, $46 330-$56 301]). Sex differences persisted after multivariable adjustment ($227 783 [95% CI, $224 117-$231 448] vs $247 661 [95% CI, $245 065-$250 258] with an absolute difference of $19 878 [95% CI, $15 261-$24 495]). Sex differences in salary varied across specialties, institutions, and faculty ranks. For example, adjusted salaries of female full professors ($250 971 [95% CI, $242 307-$259 635]) were comparable to those of male associate professors ($247 212 [95% CI, $241 850-$252 575]). Among specialties, adjusted salaries were highest in orthopedic surgery ($358 093 [95% CI, $344 354-$371 831]), surgical subspecialties ($318 760 [95

Sex Differences in Neonatal Stress Reactivity.

ERIC Educational Resources Information Center

Davis, Maryann; Emory, Eugene

1995-01-01

Examined the sex differences in physiological and behavioral stress reactivity among 36 healthy, full-term neonates after a mildly stressful behavioral assessment procedure. Salivary cortisol, heart rate change, Neonatal Behavior Assessment Scale (NBAS) cluster scores, and behavioral states after the NBAS provided 100% discrimination between male…

Cognitive Styles: Sex and Ethnic Differences.

ERIC Educational Resources Information Center

Jones, Dionne J.

This paper reviews the hallmark studies of field dependence-independence and considers the evidence for sex and ethnic differences in cognitive style. Research has traditionally linked females' early verbal superiority with field dependence and males' superior visuospatial skills with field independence. Studies challenging this picture cite…

26 CFR 1.1031(e)-1 - Exchange of livestock of different sexes.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 26 Internal Revenue 11 2012-04-01 2012-04-01 false Exchange of livestock of different sexes. 1.1031(e)-1 Section 1.1031(e)-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY... Exchange of livestock of different sexes. Section 1031(e) provides that livestock of different sexes are...

26 CFR 1.1031(e)-1 - Exchange of livestock of different sexes.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 26 Internal Revenue 11 2013-04-01 2013-04-01 false Exchange of livestock of different sexes. 1.1031(e)-1 Section 1.1031(e)-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY... Exchange of livestock of different sexes. Section 1031(e) provides that livestock of different sexes are...

26 CFR 1.1031(e)-1 - Exchange of livestock of different sexes.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 26 Internal Revenue 11 2011-04-01 2011-04-01 false Exchange of livestock of different sexes. 1.1031(e)-1 Section 1.1031(e)-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY... Exchange of livestock of different sexes. Section 1031(e) provides that livestock of different sexes are...

26 CFR 1.1031(e)-1 - Exchange of livestock of different sexes.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 26 Internal Revenue 11 2014-04-01 2014-04-01 false Exchange of livestock of different sexes. 1.1031(e)-1 Section 1.1031(e)-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY... Exchange of livestock of different sexes. Section 1031(e) provides that livestock of different sexes are...

Sex-related differences on a task of volume and density

NASA Astrophysics Data System (ADS)

Howe, Ann C.; Shayer, Michael

A sex-related difference, favoring boys, was found on initial performance of two samples (one British, one American) of 10- and 11-year-old children on a task of volume and density. After a period of classroom instruction that included opportunities for children to interact with appropriate materials and each other, both boys and girls performed at a higher level on the task, but the difference between them remained the same. There was no indication of a sex-related difference other than a time lag, in pattern of development of the concept. The question of why there is a sex-related difference, which persists in spite of experience and instruction, is discussed.

Sex Differences in Trajectories of Offending among Puerto Rican Youth

ERIC Educational Resources Information Center

Jennings, Wesley G.; Maldonado-Molina, Mildred M.; Piquero, Alex R.; Odgers, Candice L.; Bird, Hector; Canino, Glorisa

2010-01-01

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…

Sex differences in the outcomes of stent implantation in mini-swine model.

PubMed

Kunio, Mie; Wong, Gee; Markham, Peter M; Edelman, Elazer R

2018-01-01

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.

SEX DIFFERENCES IN THE USE OF COPING STRATEGIES: PREDICTORS OF ANXIETY AND DEPRESSIVE SYMPTOMS

PubMed Central

Kelly, Megan M.; Tyrka, Audrey R.; Price, Lawrence H.; Carpenter, Linda L.

2015-01-01

This study examined sex differences in the use of coping strategies and their relationship to depression and anxiety-related psychopathology. Responses on measures of coping strategies, depression, and anxiety were obtained from a carefully screened nonclinical sample (N =107). The results demonstrated that women who used less positive reframing had higher levels of depressive symptoms compared with women who used more positive reframing and to men irrespective of their use of more or less positive reframing. In addition, women who reported the use of more self-blame had elevated levels of trait anxiety, although a similar effect was not found for men. The observed sex differences in the use of coping strategies and their association with depression and anxiety-related problems underscores differences in the clinical presentation of anxiety and depression between women and men. PMID:17603810

Sex differences in DNA methylation of the cord blood are related to sex-bias psychiatric diseases

PubMed Central

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

2017-01-01

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. PMID:28303968

Sex differences in DNA methylation of the cord blood are related to sex-bias psychiatric diseases

NASA Astrophysics Data System (ADS)

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

2017-03-01

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.

Sex differences in empathy and its relation to juvenile offending.

PubMed

Broidy, Lisa; Cauffman, Elizabeth; Espelage, Dorothy L; Mazerolle, Paul; Piquero, Alex

2003-10-01

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.

Sex Differences in World-Record Performance: The Influence of Sport Discipline and Competition Duration.

PubMed

Sandbakk, Øyvind; Solli, Guro Strøm; Holmberg, Hans-Christer

2018-01-01

The current review summarizes scientific knowledge concerning sex differences in world-record performance and the influence of sport discipline and competition duration. In addition, the way that physiological factors relate to sex dimorphism is discussed. While cultural factors played a major role in the rapid improvement of performance of women relative to men up until the 1990s, sex differences between the world's best athletes in most events have remained relatively stable at approximately 8-12%. The exceptions are events in which upper-body power is a major contributor, where this difference is more than 12%, and ultraendurance swimming, where the gap is now less than 5%. The physiological advantages in men include a larger body size with more skeletal-muscle mass, a lower percentage of body fat, and greater maximal delivery of anaerobic and aerobic energy. The greater strength and anaerobic capacity in men normally disappear when normalized for fat-free body mass, whereas the higher hemoglobin concentrations lead to 5-10% greater maximal oxygen uptake in men with such normalization. The higher percentage of muscle mass in the upper body of men results in a particularly large sex difference in power production during upper-body exercise. While the exercise efficiency of men and women is usually similar, women have a better capacity to metabolize fat and demonstrate better hydrodynamics and more even pacing, which may be advantageous, in particular during long-lasting swimming competitions.

Men, women…who cares? A population-based study on sex differences and gender roles in empathy and moral cognition.

PubMed

Baez, Sandra; Flichtentrei, Daniel; Prats, María; Mastandueno, Ricardo; García, Adolfo M; Cetkovich, Marcelo; Ibáñez, Agustín

2017-01-01

Research on sex differences in empathy has revealed mixed findings. Whereas experimental and neuropsychological measures show no consistent sex effect, self-report data consistently indicates greater empathy in women. However, available results mainly come from separate populations with relatively small samples, which may inflate effect sizes and hinder comparability between both empirical corpora. To elucidate the issue, we conducted two large-scale studies. First, we examined whether sex differences emerge in a large population-based sample (n = 10,802) when empathy is measured with an experimental empathy-for-pain paradigm. Moreover, we investigated the relationship between empathy and moral judgment. In the second study, a subsample (n = 334) completed a self-report empathy questionnaire. Results showed some sex differences in the experimental paradigm, but with minuscule effect sizes. Conversely, women did portray themselves as more empathic through self-reports. In addition, utilitarian responses to moral dilemmas were less frequent in women, although these differences also had small effect sizes. These findings suggest that sex differences in empathy are highly driven by the assessment measure. In particular, self-reports may induce biases leading individuals to assume gender-role stereotypes. Awareness of the role of measurement instruments in this field may hone our understanding of the links between empathy, sex differences, and gender roles.

Men, women…who cares? A population-based study on sex differences and gender roles in empathy and moral cognition

PubMed Central

Baez, Sandra; Flichtentrei, Daniel; Prats, María; Mastandueno, Ricardo; García, Adolfo M.; Cetkovich, Marcelo

2017-01-01

Research on sex differences in empathy has revealed mixed findings. Whereas experimental and neuropsychological measures show no consistent sex effect, self-report data consistently indicates greater empathy in women. However, available results mainly come from separate populations with relatively small samples, which may inflate effect sizes and hinder comparability between both empirical corpora. To elucidate the issue, we conducted two large-scale studies. First, we examined whether sex differences emerge in a large population-based sample (n = 10,802) when empathy is measured with an experimental empathy-for-pain paradigm. Moreover, we investigated the relationship between empathy and moral judgment. In the second study, a subsample (n = 334) completed a self-report empathy questionnaire. Results showed some sex differences in the experimental paradigm, but with minuscule effect sizes. Conversely, women did portray themselves as more empathic through self-reports. In addition, utilitarian responses to moral dilemmas were less frequent in women, although these differences also had small effect sizes. These findings suggest that sex differences in empathy are highly driven by the assessment measure. In particular, self-reports may induce biases leading individuals to assume gender-role stereotypes. Awareness of the role of measurement instruments in this field may hone our understanding of the links between empathy, sex differences, and gender roles. PMID:28632770

Differences in Religiousness in Opposite-Sex and Same-Sex Twins in a Secular Society.

PubMed

Ahrenfeldt, Linda J; Lindahl-Jacobsen, Rune; Möller, Sören; Christensen, Kaare; Hvidtjørn, Dorte; Hvidt, Niels Christian

2016-02-01

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.

Differences in Religiousness in Opposite-Sex and Same-Sex Twins in a Secular Society

PubMed Central

Ahrenfeldt, Linda J.; Lindahl-Jacobsen, Rune; Möller, Sören; Christensen, Kaare; Hvidtjørn, Dorte; Hvidt, Niels Christian

2016-01-01

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. PMID:26689907

26 CFR 1.1031(e)-1 - Exchange of livestock of different sexes.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 26 Internal Revenue 11 2010-04-01 2010-04-01 true Exchange of livestock of different sexes. 1.1031(e)-1 Section 1.1031(e)-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY... livestock of different sexes. Section 1031(e) provides that livestock of different sexes are not property of...

Sex-related differences in attention and memory.

PubMed

Solianik, Rima; Brazaitis, Marius; Skurvydas, Albertas

2016-01-01

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 (P<0.05) in men. Coefficients of variation positively correlated (P<0.05) with attention task incorrect response and negatively correlated (P<0.05) with correct answers in the memory 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.

Sex differences in cortisol's regulation of affiliative behavior.

PubMed

Sherman, Gary D; Rice, Leslie K; Jin, Ellie Shuo; Jones, Amanda C; Josephs, Robert A

2017-06-01

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.

Why Sex Based Language Differences are Elusive.

ERIC Educational Resources Information Center

Tyler, Mary

Paradoxically, linguists' speculations about sex differences in language use are highly plausible and yet have received little empirical support from well controlled studies. An experiment was designed to correct a flaw in earlier methodologies by sampling precisely the kinds of situations in which predicted differences (e.g., swearing,…

Sex and Age Differences in Trail Half Marathon Running.

PubMed

Navalta, James W; Montes, Jeffrey; Tanner, Elizabeth A; Bodell, Nathaniel G; Young, John C

2018-01-01

Female participation is growing in trail running races. The purpose was to evaluate sex and age differences in top finishers of a trail running half marathon. Velocity differences between males (M) and females (F) were determined for the top 10 finishers of the Moab Trail Half Marathon from 2012 - 2015 across age, and by finishing place. Differences between age category and between sexes were determined through ANOVA with significance accepted at P < 0.05. A significant difference for running velocity was present between sexes at each age category (20-29 yr F = 2.9±0.3, M = 3.4±0.4 m·sec -1 ; 30-39 yr F = 2.8±0.3, M = 3.3±0.3; 40-49 yr F = 2.7±0.3, M = 3.0±0.5; 50-59 yr F = 2.3±0.2, M = 2.8±0.3; 60-69 yr F = 1.6±0.3, M = 2.2±0.4; P < 0.0001). Sex difference in trail running velocity was consistent (~13%) among all age categories with exception of the oldest group (33%, P = 0.0001). There were significantly greater female finishers in every age category (20 - 29 yr F = 107±18, M = 56±1;, 30 - 39 yr F = 150±34, M = 84±21; 40 - 49 yr F = 112±17, M = 64±16; P < 0.01) until 50 - 59 yr (F = 48±13, M = 41±14; P = 0.50). These data indicate that the widening gap in sex differences observed in road races are ameliorated in a trail running environment that has a larger number of female participants.

Differences in Gay Male Couples' Use of Drugs and Alcohol With Sex by Relationship HIV Status.

PubMed

Mitchell, Jason W

2016-07-01

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.

Evidence for sex differences in cardiovascular aging and adaptive responses to physical activity.

PubMed

Parker, Beth A; Kalasky, Martha J; Proctor, David N

2010-09-01

There are considerable data addressing sex-related differences in cardiovascular system aging and disease risk/progression. Sex differences in cardiovascular aging are evident during resting conditions, exercise, and other acute physiological challenges (e.g., orthostasis). In conjunction with these sex-related differences-or perhaps even as an underlying cause-the impact of cardiorespiratory fitness and/or physical activity on the aging cardiovascular system also appears to be sex-specific. Potential mechanisms contributing to sex-related differences in cardiovascular aging and adaptability include changes in sex hormones with age as well as sex differences in baseline fitness and the dose of activity needed to elicit cardiovascular adaptations. The purpose of the present paper is thus to review the primary research regarding sex-specific plasticity of the cardiovascular system to fitness and physical activity in older adults. Specifically, the paper will (1) briefly review known sex differences in cardiovascular aging, (2) detail emerging evidence regarding observed cardiovascular outcomes in investigations of exercise and physical activity in older men versus women, (3) explore mechanisms underlying the differing adaptations to exercise and habitual activity in men versus women, and (4) discuss implications of these findings with respect to chronic disease risk and exercise prescription.