Sekine, Michikazu; Chandola, Tarani; Martikainen, Pekka; Marmot, Michael; Kagamimori, Sadanobu
2010-12-01
Poor physical and mental functioning are more common among women than men and those with disadvantaged work and family characteristics. This study aims to clarify whether sex differences in health functioning can be explained by sex differences in work and family characteristics. The subjects were 3787 civil servants (2525 men and 1262 women), aged 20-65, working in a local government on the west coast of Japan. A questionnaire survey was conducted in January 2003. Low employment grade, high demands, long work hours, shift work, being unmarried, having no young children, high family-to-work conflict and high work-to-family conflict were more common among women than men and were independently associated with poor physical and mental functioning. The age-adjusted odds ratios (ORs) of women for poor health functioning were 1.80 for poor physical functioning and 1.77 for poor mental functioning. When adjusted for employment grade and work characteristics (control, demand, support, work hours, and shift work), the sex differences in health functioning attenuated. When adjusted for family characteristics (family structure and work-family conflicts), the sex differences in health functioning further attenuated and were no longer statistically significant. Sex differences in family characteristics contributed more to sex difference in mental functioning than sex differences in work characteristics. Japan belongs to conservative welfare regimes. In such countries, men are able to concentrate on their work with relative freedom from their family tasks and responsibilities, whereas women feel difficulties in maintaining their work-life balances. Such sex differences in work- and family-related stresses may contribute to sex difference in health. Longitudinal research is necessary to clarify the causal nature of these associations. Copyright © 2010 Elsevier Ltd. All rights reserved.
Sex in the brain: hormones and sex differences.
Marrocco, Jordan; McEwen, Bruce S
2016-12-01
Contrary to popular belief, sex hormones act throughout the entire brain of both males and females via both genomic and nongenomic receptors. Many neural and behavioral functions are affected by estrogens, 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, indicate that we are entering a new era in our ability to understand and appreciate the diversity of gender-related behaviors and brain functions.
Sex-related differences in amygdala functional connectivity during resting conditions.
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.
The Role of Sex in Memory Function: Considerations and Recommendations in the Context of Exercise.
Loprinzi, Paul D; Frith, Emily
2018-05-31
There is evidence to suggest that biological sex plays a critical role in memory function, with sex differentially influencing memory type. In this review, we detail the current evidence evaluating sex-specific effects on various memory types. We also discuss potential mechanisms that explain these sex-specific effects, which include sex differences in neuroanatomy, neurochemical differences, biological differences, and cognitive and affect-related differences. Central to this review, we also highlight that, despite the established sex differences in memory, there is little work directly comparing whether males and females have a differential exercise-induced effect on memory function. As discussed herein, such a differential effect is plausible given the clear sex-specific effects on memory, exercise response, and molecular mediators of memory. We emphasize that future work should be carefully powered to detect sex differences. Future research should also examine these potential exercise-related sex-specific effects for various memory types and exercise intensities and modalities. This will help enhance our understanding of whether sex indeed moderates the effects of exercise and memory function, and as such, will improve our understanding of whether sex-specific, memory-enhancing interventions should be developed, implemented, and evaluated.
Sex differences in the brain-an interplay of sex steroid hormones and sex chromosomes.
Grgurevic, Neza; Majdic, Gregor
2016-09-01
Although considerable progress has been made in our understanding of brain function, many questions remain unanswered. The ultimate goal of studying the brain is to understand the connection between brain structure and function and behavioural outcomes. Since sex differences in brain morphology were first observed, subsequent studies suggest different functional organization of the male and female brains in humans. Sex and gender have been identified as being a significant factor in understanding human physiology, health and disease, and the biological differences between the sexes is not limited to the gonads and secondary sexual characteristics, but also affects the structure and, more crucially, the function of the brain and other organs. Significant variability in brain structures between individuals, in addition to between the sexes, is factor that complicates the study of sex differences in the brain. In this review, we explore the current understanding of sex differences in the brain, mostly focusing on preclinical animal studies. © 2016 The Author(s). published by Portland Press Limited on behalf of the Biochemical Society.
Sex differences in cognitive impairment and Alzheimer's disease.
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 Cognitive Impairment and Alzheimer’s Disease
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
Hausmann, Markus
2017-01-02
Biological sex and sex hormones are known to affect functional cerebral asymmetries (FCAs). Men are generally more lateralized than women. The effect size of this sex difference is small but robust. Some of the inconsistencies in the literature may be explained by sex-related hormonal differences. Most studies focusing on neuromodulatory properties of sex hormones on FCAs have investigated women during the menstrual cycle. Although contradictions exist, these studies have typically shown that levels of estradiol and/or progesterone correlate with the degree of FCAs, suggesting that sex differences in FCAs partially depend on hormonal state and day of testing. The results indicate that FCAs are not fixed but are hormone dependent, and as such they can dynamically change within relatively short periods throughout life. Many issues raised in this Mini-Review refer not only to FCAs but also to other aspects of functional brain organization, such as functional connectivity within and between the cerebral hemispheres. Our understanding of sex differences in brain and behavior as well as their clinical relevance will improve significantly if more studies routinely take sex and sex hormones into account. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Corre, Christina; Friedel, Miriam; Vousden, Dulcie A; Metcalf, Ariane; Spring, Shoshana; Qiu, Lily R; Lerch, Jason P; Palmert, Mark R
2016-03-01
Males and females exhibit several differences in brain structure and function. To examine the basis for these sex differences, we investigated the influences of sex hormones and sex chromosomes on brain structure and function in mice. We used the Four Core Genotype (4CG) mice, which can generate both male and female mice with XX or XY sex chromosome complement, allowing the decoupling of sex chromosomes from hormonal milieu. To examine whole brain structure, high-resolution ex vivo MRI was performed, and to assess differences in cognitive function, mice were trained on a radial arm maze. Voxel-wise and volumetric analyses of MRI data uncovered a striking independence of hormonal versus chromosomal influences in 30 sexually dimorphic brain regions. For example, the bed nucleus of the stria terminalis and the parieto-temporal lobe of the cerebral cortex displayed steroid-dependence while the cerebellar cortex, corpus callosum, and olfactory bulbs were influenced by sex chromosomes. Spatial learning and memory demonstrated strict hormone-dependency with no apparent influence of sex chromosomes. Understanding the influences of chromosomes and hormones on brain structure and function is important for understanding sex differences in brain structure and function, an endeavor that has eventual implications for understanding sex biases observed in the prevalence of psychiatric disorders.
Vaskinn, Anja; Sundet, Kjetil; Simonsen, Carmen; Hellvin, Tone; Melle, Ingrid; Andreassen, Ole A
2011-07-01
To investigate sex differences in neurocognition and social functioning in schizophrenia and bipolar disorder and the possible role of sex as a moderator of this relationship. Participants with schizophrenia (60 women/94 men), bipolar I disorder (55 women/51 men), and healthy controls (158 women/182 men) were assessed with an extensive neuropsychological test battery and a social functioning questionnaire. We found significant main effects of sex for neuropsychological tests (p < .001, η² = 0.10) and social functioning (p < .001, η² = 0.05), with men scoring below women. Women performed better than men for all neuropsychological tests (except attention and working memory). Both clinical groups performed below healthy controls for all neuropsychological tests (except attention). Post hoc comparisons of persons with schizophrenia and healthy controls yielded significant interaction effects (p < .05) for three neuropsychological tests (California Verbal Learning Test II [CVLT-II], Color-Word Interference, and Interference/Switching), with men with schizophrenia being disproportionally disadvantaged compared with their female counterparts. Regression analyses investigating sex as a moderator between neurocognition and social functioning showed that neurocognition predicted social functioning in schizophrenia, whereas sex predicted social functioning in healthy controls. Sex was not a moderator in any of the three groups. This study is the first to find neurocognitive sex differences for bipolar disorder and replicated previous findings for schizophrenia. The data did not support the hypothesis that sex is a moderator between neurocognition and social functioning. Clinical implications include the use of different cognitive remediation strategies based on sex. PsycINFO Database Record (c) 2011 APA, all rights reserved.
Sex Differences in Brain-Derived Neurotrophic Factor Signaling and Functions
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
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.
A systematic literature review of sex differences in childhood language and brain development.
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.
Alarcón, Gabriela; Cservenka, Anita; Fair, Damien A.; Nagel, Bonnie J.
2014-01-01
Adolescence is a developmental period characterized by notable changes in behavior, physical attributes, and an increase in endogenous sex steroid hormones, which may impact cognitive functioning. Moreover, sex differences in brain structure are present, leading to differences in neural function and cognition. Here, we examine sex differences in performance and blood oxygen level-dependent (BOLD) activation in a sample of adolescents during a spatial working memory (SWM) task. We also examine whether endogenous testosterone levels mediate differential brain activity between the sexes. Adolescents between ages 10 and 16 completed a SWM functional magnetic resonance imaging (fMRI) task, and serum hormone levels were assessed within seven days of scanning. While there were no sex differences in task performance (accuracy and reaction time), differences in BOLD response between girls and boys emerged, with girls deactivating brain regions in the default mode network and boys showing increased response in SWM-related brain regions of the frontal cortex. These results suggest that adolescent boys and girls adopted distinct neural strategies, while maintaining spatial cognitive strategies that facilitated comparable cognitive performance of a SWM task. A nonparametric bootstrapping procedure revealed that testosterone did not mediate sex-specific brain activity, suggesting that sex differences in BOLD activation during SWM may be better explained by other factors, such as early organizational effects of sex steroids or environmental influences. Elucidating sex differences in neural function and the influence of gonadal hormones can serve as a basis of comparison for understanding sexually dimorphic neurodevelopment and inform sex-specific psychopathology that emerges in adolescence. PMID:25312831
Understanding the broad influence of sex hormones and sex differences in the brain.
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.
Understanding the Broad Influence of Sex Hormones and Sex Differences in the Brain
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 differences in normal age trajectories of functional brain networks.
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.
Evolving knowledge of sex differences in brain structure, function, and chemistry.
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.
Wheaton, Felicia V; Crimmins, Eileen M
2016-07-01
The objectives were to determine whether women always fare more poorly in terms of physical function and disability across countries that vary widely in terms of their level of development, epidemiologic context and level of gender equality. Sex differences in self-reported and objective measures of disability and physical function were compared among older adults aged 55-85 in the United States of America, Taiwan, Korea, Mexico, China, Indonesia and among the Tsimane of Bolivia using population-based studies collected between 2001 and 2011. Data were analysed using logistic and ordinary least-squares regression. Confidence intervals were examined to see whether the effect of being female differed significantly between countries. In all countries, women had consistently worse physical functioning (both self-reported and objectively measured). Women also tended to report more difficulty with activities of daily living (ADL), although differences were not always significant. In general, sex differences across measures were less pronounced in China. In Korea, women had significantly lower grip strength, but sex differences in ADL difficulty were non-significant or even reversed. Education and marital status helped explain sex differences. Overall, there was striking similarity in the magnitude and direction of sex differences across countries despite considerable differences in context, although modest variations in the effect of sex were observed.
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)
ERIC Educational Resources Information Center
Bolte, Sven; Duketis, Eftichia; Poustka, Fritz; Holtmann, Martin
2011-01-01
Despite the skewed sex ratio, few studies have addressed possible cognitive sex differences in autism spectrum disorders (ASDs). This study compared visual attention to detail (ATTD) and selected executive functions (EF) in 35 males and 21 females with higher-functioning ASD and unaffected sibling controls. Females with ASD outperformed males on…
Alarcón, Gabriela; Cservenka, Anita; Fair, Damien A; Nagel, Bonnie J
2014-12-17
Adolescence is a developmental period characterized by notable changes in behavior, physical attributes, and an increase in endogenous sex steroid hormones, which may impact cognitive functioning. Moreover, sex differences in brain structure are present, leading to differences in neural function and cognition. Here, we examine sex differences in performance and blood oxygen level-dependent (BOLD) activation in a sample of adolescents during a spatial working memory (SWM) task. We also examine whether endogenous testosterone levels mediate differential brain activity between the sexes. Adolescents between ages 10 and 16 years completed a SWM functional magnetic resonance imaging (fMRI) task, and serum hormone levels were assessed within seven days of scanning. While there were no sex differences in task performance (accuracy and reaction time), differences in BOLD response between girls and boys emerged, with girls deactivating brain regions in the default mode network and boys showing increased response in SWM-related brain regions of the frontal cortex. These results suggest that adolescent boys and girls adopted distinct neural strategies, while maintaining spatial cognitive strategies that facilitated comparable cognitive performance of a SWM task. A nonparametric bootstrapping procedure revealed that testosterone did not mediate sex-specific brain activity, suggesting that sex differences in BOLD activation during SWM may be better explained by other factors, such as early organizational effects of sex steroids or environmental influences. Elucidating sex differences in neural function and the influence of gonadal hormones can serve as a basis of comparison for understanding sexually dimorphic neurodevelopment and inform sex-specific psychopathology that emerges in adolescence. Copyright © 2014 Elsevier B.V. All rights reserved.
Ceylan-Isik, Asli F.; Li, Qun; Ren, Jun
2011-01-01
Sex difference in cardiac contractile function exists which may contribute to the different prevalence in cardiovascular diseases between genders. However, the precise mechanisms of action behind sex difference in cardiac function are still elusive. Given that sex difference exists in insulin-like growth factor I (IGF-1) cascade, this study is designed to evaluate the impact of severe liver IGF-1 deficiency (LID) on sex difference in cardiac function. Echocardiographic, cardiomyocyte contractile and intracellular Ca2+ properties were evaluated including ventricular geometry, fractional shortening, peak shortening, maximal velocity of shortening/relengthening (± dL/dt), time-to-peak shortening (TPS), time-to-90% relengthening (TR90), fura-fluorescence intensity (FFI) and intracellular Ca2+ clearance. Female C57 mice exhibited significantly higher plasma IGF-1 levels than their male counterpart. LID mice possessed comparably low IGF-1 levels in both sexes. Female C57 and LID mice displayed lower body, heart and liver weights compared to male counterparts. Echocardiographic analysis revealed larger LV mass in female C57 but not LID mice without sex difference in other cardiac geometric indices. Myocytes from female C57 mice exhibited reduced peak shortening, ± dL/dt, longer TPS, TR90 and intracellular Ca2+ clearance compared with males. Interestingly, this sex difference was greatly attenuated or abolished by IGF-1 deficiency. Female C57 mice displayed significantly decreased mRNA and protein levels of Na+-Ca2+ exchanger, SERCA2a and phosphorylated phospholamban as well as SERCA activity compared with male C57 mice. These sex differences in Ca2+ regulatory proteins were abolished or overtly attenuated by IGF-1 deficiency. In summary, our data suggested that IGF-1 deficiency may significantly attenuated or mitigate the sex difference in cardiomyocyte contractile function associated with intracellular Ca2+ regulation. PMID:21763763
Ceylan-Isik, Asli F; Li, Qun; Ren, Jun
2011-10-10
Sex difference in cardiac contractile function exists which may contribute to the different prevalence in cardiovascular diseases between genders. However, the precise mechanisms of action behind sex difference in cardiac function are still elusive. Given that sex difference exists in insulin-like growth factor I (IGF-1) cascade, this study is designed to evaluate the impact of severe liver IGF-1 deficiency (LID) on sex difference in cardiac function. Echocardiographic, cardiomyocyte contractile and intracellular Ca(2+) properties were evaluated including ventricular geometry, fractional shortening, peak shortening, maximal velocity of shortening/relengthening (±dL/dt), time-to-peak shortening (TPS), time-to-90% relengthening (TR(90)), fura-fluorescence intensity (FFI) and intracellular Ca(2+) clearance. Female C57 mice exhibited significantly higher plasma IGF-1 levels than their male counterpart. LID mice possessed comparably low IGF-1 levels in both sexes. Female C57 and LID mice displayed lower body, heart and liver weights compared to male counterparts. Echocardiographic analysis revealed larger LV mass in female C57 but not LID mice without sex difference in other cardiac geometric indices. Myocytes from female C57 mice exhibited reduced peak shortening, ±dL/dt, longer TPS, TR(90) and intracellular Ca(2+) clearance compared with males. Interestingly, this sex difference was greatly attenuated or abolished by IGF-1 deficiency. Female C57 mice displayed significantly decreased mRNA and protein levels of Na(+)-Ca(2+) exchanger, SERCA2a and phosphorylated phospholamban as well as SERCA activity compared with male C57 mice. These sex differences in Ca(2+) regulatory proteins were abolished or overtly attenuated by IGF-1 deficiency. In summary, our data suggested that IGF-1 deficiency may significantly attenuated or mitigate the sex difference in cardiomyocyte contractile function associated with intracellular Ca(2+) regulation. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.
Six Degrees of Separation: What Teachers Need to Know about the Emerging Science of Sex Differences
ERIC Educational Resources Information Center
Sax, Leonard
2006-01-01
In this article, the author discusses several research reports demonstrating the existence of sex differences in cognitive function and language skills. Although dozens of studies published in the past five years have demonstrated dramatic sex differences in autonomic function, the educational literature has not emphasized those studies and their…
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…
Her versus his migraine: multiple sex differences in brain function and structure
Linnman, Clas; Brawn, Jennifer; Burstein, Rami; Becerra, Lino; Borsook, David
2012-01-01
Migraine is twice as common in females as in males, but the mechanisms behind this difference are still poorly understood. We used high-field magnetic resonance imaging in male and female age-matched interictal (migraine free) migraineurs and matched healthy controls to determine alterations in brain structure. Female migraineurs had thicker posterior insula and precuneus cortices compared with male migraineurs and healthy controls of both sexes. Furthermore, evaluation of functional responses to heat within the migraine groups indicated concurrent functional differences in male and female migraineurs and a sex-specific pattern of functional connectivity of these two regions with the rest of the brain. The results support the notion of a ‘sex phenotype’ in migraine and indicate that brains are differentially affected by migraine in females compared with males. Furthermore, the results also support the notion that sex differences involve both brain structure as well as functional circuits, in that emotional circuitry compared with sensory processing appears involved to a greater degree in female than male migraineurs. PMID:22843414
Her versus his migraine: multiple sex differences in brain function and structure.
Maleki, Nasim; Linnman, Clas; Brawn, Jennifer; Burstein, Rami; Becerra, Lino; Borsook, David
2012-08-01
Migraine is twice as common in females as in males, but the mechanisms behind this difference are still poorly understood. We used high-field magnetic resonance imaging in male and female age-matched interictal (migraine free) migraineurs and matched healthy controls to determine alterations in brain structure. Female migraineurs had thicker posterior insula and precuneus cortices compared with male migraineurs and healthy controls of both sexes. Furthermore, evaluation of functional responses to heat within the migraine groups indicated concurrent functional differences in male and female migraineurs and a sex-specific pattern of functional connectivity of these two regions with the rest of the brain. The results support the notion of a 'sex phenotype' in migraine and indicate that brains are differentially affected by migraine in females compared with males. Furthermore, the results also support the notion that sex differences involve both brain structure as well as functional circuits, in that emotional circuitry compared with sensory processing appears involved to a greater degree in female than male migraineurs.
Sex Differences in Kappa Opioid Receptor Function and Their Potential Impact on Addiction
Chartoff, Elena H.; Mavrikaki, Maria
2015-01-01
Behavioral, biological, and social sequelae that lead to drug addiction differ between men and women. Our efforts to understand addiction on a mechanistic level must include studies in both males and females. Stress, anxiety, and depression are tightly linked to addiction, and whether they precede or result from compulsive drug use depends on many factors, including biological sex. The neuropeptide dynorphin (DYN), an endogenous ligand at kappa opioid receptors (KORs), is necessary for stress-induced aversive states and is upregulated in the brain after chronic exposure to drugs of abuse. KOR agonists produce signs of anxiety, fear, and depression in laboratory animals and humans, findings that have led to the hypothesis that drug withdrawal-induced DYN release is instrumental in negative reinforcement processes that drive addiction. However, these studies were almost exclusively conducted in males. Only recently is evidence available that there are sex differences in the effects of KOR activation on affective state. This review focuses on sex differences in DYN and KOR systems and how these might contribute to sex differences in addictive behavior. Much of what is known about how biological sex influences KOR systems is from research on pain systems. The basic molecular and genetic mechanisms that have been discovered to underlie sex differences in KOR function in pain systems may apply to sex differences in KOR function in reward systems. Our goals are to discuss the current state of knowledge on how biological sex contributes to KOR function in the context of pain, mood, and addiction and to explore potential mechanisms for sex differences in KOR function. We will highlight evidence that the function of DYN-KOR systems is influenced in a sex-dependent manner by: polymorphisms in the prodynorphin (pDYN) gene, genetic linkage with the melanocortin-1 receptor (MC1R), heterodimerization of KORs and mu opioid receptors (MORs), and gonadal hormones. Finally, we identify several gaps in our understanding of “if” and “how” DYN and KORs modulate addictive behavior in a sex-dependent manner. Future work may address these gaps by building on the mechanistic studies outlined in this review. Ultimately this will enable the development of novel and effective addiction treatments tailored to either males or females. PMID:26733781
Sex differences in the functional connectivity of the amygdalae in association with cortisol.
Kogler, Lydia; Müller, Veronika I; Seidel, Eva-Maria; Boubela, Roland; Kalcher, Klaudius; Moser, Ewald; Habel, Ute; Gur, Ruben C; Eickhoff, Simon B; Derntl, Birgit
2016-07-01
Human amygdalae are involved in various behavioral functions such as affective and stress processing. For these behavioral functions, as well as for psychophysiological arousal including cortisol release, sex differences are reported. Here, we assessed cortisol levels and resting-state functional connectivity (rsFC) of left and right amygdalae in 81 healthy participants (42 women) to investigate potential modulation of amygdala rsFC by sex and cortisol concentration. Our analyses revealed that rsFC of the left amygdala significantly differed between women and men: Women showed stronger rsFC than men between the left amygdala and left middle temporal gyrus, inferior frontal gyrus, postcentral gyrus and hippocampus, regions involved in face processing, inner-speech, fear and pain processing. No stronger connections were detected for men and no sex difference emerged for right amygdala rsFC. Also, an interaction of sex and cortisol appeared: In women, cortisol was negatively associated with rsFC of the amygdalae with striatal regions, mid-orbital frontal gyrus, anterior cingulate gyrus, middle and superior frontal gyri, supplementary motor area and the parietal-occipital sulcus. Contrarily in men, positive associations of cortisol with rsFC of the left amygdala and these structures were observed. Functional decoding analyses revealed an association of the amygdalae and these regions with emotion, reward and memory processing, as well as action execution. Our results suggest that functional connectivity of the amygdalae as well as the regulatory effect of cortisol on brain networks differs between women and men. These sex-differences and the mediating and sex-dependent effect of cortisol on brain communication systems should be taken into account in affective and stress-related neuroimaging research. Thus, more studies including both sexes are required. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.
Neural sex modifies the function of a C. elegans sensory circuit.
Lee, Kyunghwa; Portman, Douglas S
2007-11-06
Though sex differences in animal behavior are ubiquitous, their neural and genetic underpinnings remain poorly understood. In particular, the role of functional differences in the neural circuitry that is shared by both sexes has not been extensively investigated. We have addressed these issues with C. elegans olfaction, a simple innate behavior mediated by sexually isomorphic neurons. Though males respond to the same olfactory attractants as do hermaphrodites, we find that each sex has a characteristic repertoire of olfactory preferences. These are not secondary to other sex-specific behaviors and do not require signaling from the gonad. Sex-specific olfactory preferences are controlled by tra-1, the master regulator of C. elegans sexual differentiation. Moreover, the genetic masculinization of neurons in an otherwise wild-type hermaphrodite is sufficient to switch the sexual phenotype of olfactory preference behavior. These studies reveal novel and unexpected sex differences in a C. elegans sensory behavior that is exhibited by both sexes. Our results indicate that these differences are a function of the chromosomally determined sexual identity of shared neural circuitry.
Salerni, Sara; Di Francescomarino, Samanta; Cadeddu, Christian; Acquistapace, Flavio; Maffei, Silvia; Gallina, Sabina
2015-06-01
Human response to different physiologic stimuli and cardiovascular (CV) adaptation to various pathologies seem to be gender specific. Sex-steroid hormones have been postulated as the major contributors towards these sex-related differences. This review will discuss current evidence on gender differences in CV function and remodelling, and will present the different role of the principal sex-steroid hormones on female heart. Starting from a review of sex hormones synthesis, receptors and CV signalling, we will summarize the current knowledge concerning the role of sex hormones on the regulation of our daily activities throughout the life, via the modulation of autonomic nervous system, excitation-contraction coupling pathway and ion channels activity. Many unresolved questions remain even if oestrogen effects on myocardial remodelling and function have been extensively studied. So this work will focus attention also on the controversial and complex relationship existing between androgens, progesterone and female heart. © 2015 Stichting European Society for Clinical Investigation Journal Foundation.
Sex and gender differences in substance use disorders.
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 and anesthesiology: preface and comments].
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.
Juvenile sex offenders compared to non-sex offenders: a review of the literature 1995-2005.
van Wijk, Anton; Vermeiren, Robert; Loeber, Rolf; 't Hart-Kerkhoffs, Lisette; Doreleijers, Theo; Bullens, Ruud
2006-10-01
An unresolved but clinically important issue in the literature on juvenile delinquency is to what extent juvenile sex offenders resemble non-sex offenders with respect to individual, familial, and environmental characteristics. The current article reviewed published studies (1995-2005) comparing sex offenders with non-sex offenders. The 17 articles meeting the inclusion criteria suggest that differences exist between sex offenders and non-sex offenders on personality characteristics, behavioral problems, history of sexual abuse, nonsexual offending, and peer functioning. Inconsistent results were found for demographic factors, family functioning and background, antisocial attitudes, and intellectual and neurological functioning. Although it is likely that sex offenders can be differentiated from nonsex offenders on a number of characteristics, caution is warranted because of methodological differences between studies and small samples size. Also, studies show that sex offenders are a heterogeneous group. Further research should take into account this heterogeneity by including sex offenders from clearly circumscribed groups and investigating characteristics specifically related to sexual behavior.
Cerebral sex dimorphism and sexual orientation.
Manzouri, Amirhossein; Savic, Ivanka
2018-03-01
The neurobiology of sexual orientation is frequently discussed in terms of cerebral sex dimorphism (defining both functional and structural sex differences). Yet, the information about possible cerebral differences between sex-matched homo and heterosexual persons is limited, particularly among women. In this multimodal MRI study, we addressed these issues by investigating possible cerebral differences between homo and heterosexual persons, and by asking whether there is any sex difference in this aspect. Measurements of cortical thickness (Cth), subcortical volumes, and functional and structural resting-state connections among 40 heterosexual males (HeM) and 40 heterosexual females (HeF) were compared with those of 30 homosexual males (HoM) and 30 homosexual females (HoF). Congruent with previous reports, sex differences were detected in heterosexual controls with regard to fractional anisotropy (FA), Cth, and several subcortical volumes. Homosexual groups did not display any sex differences in FA values. Furthermore, their functional connectivity was significantly less pronounced in the mesial prefrontal and precuneus regions. In these two particular regions, HoM also displayed thicker cerebral cortex than other groups, whereas HoF did not differ from HeF. In addition, in HoM the parietal Cth showed "sex-reversed" values, not observed in HoF. Homosexual orientation seems associated with a less pronounced sexual differentiation of white matter tracts and a less pronounced functional connectivity of the self-referential networks compared to heterosexual orientation. Analyses of Cth suggest that male and female homosexuality are not simple analogues of each other and that differences from heterosexual controls are more pronounced in HoM. © 2017 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…
[Gender differences in cognitive functions and influence of sex hormones].
Torres, A; Gómez-Gil, E; Vidal, A; Puig, O; Boget, T; Salamero, M
2006-01-01
To review scientific evidence on gender differences in cognitive functions and influence of sex hormones on cognitive performance. Systematical search of related studies identified in Medline. Women outperform men on verbal fluency, perceptual speed tasks, fine motor skills, verbal memory and verbal learning. Men outperform women on visuospatial ability, mathematical problem solving and visual memory. No gender differences on attention and working memory are found. Researchers distinguish four methods to investigate hormonal influence on cognitive performance: a) patient with hormonal disorders; b) neuroimaging in individuals during hormone administration; c) in women during different phases of menstrual cycle, and d) in patients receiving hormonal treatment (idiopathic hypogonadotropic hypogonadism, postmenopausal women and transsexuals). The findings mostly suggest an influence of sex hormones on some cognitive functions, but they are not conclusive because of limitations and scarcity of the studies. There are gender differences on cognitive functions. Sex hormones seem to influence cognitive performance.
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…
Sekine, Michikazu; Tatsuse, Takashi; Kagamimori, Sadanobu; Chandola, Tarani; Cable, Noriko; Marmot, Michael; Martikainen, Pekka; Lallukka, Tea; Rahkonen, Ossi; Lahelma, Eero
2011-01-01
In general, women report more physical and mental symptoms than men. International comparisons of countries with different welfare state regimes may provide further understanding of the social determinants of sex inequalities in health. This study aims to evaluate (1) whether there are sex inequalities in health functioning as measured by the Short Form 36 (SF-36), and (2) whether work characteristics contribute to the sex inequalities in health among employees from Britain, Finland, and Japan, representing liberal, social democratic, and conservative welfare state regimes, respectively. The participants were 7340 (5122 men and 2218 women) British employees, 2297 (1638 men and 659 women) Japanese employees, and 8164 (1649 men and 6515 women) Finnish employees. All the participants were civil servants aged 40-60 years. We found that more women than men tended to have disadvantaged work characteristics (i.e. low employment grade, low job control, high job demands, and long work hours) but such sex differences were relatively smaller among employees from Finland, where more gender equal policies exist than Britain and Japan. The age-adjusted odds ratio (OR) of women for poor physical functioning was the largest for British women (OR=2.08), followed by for Japanese women (OR=1.72), and then for Finnish women (OR=1.51). The age-adjusted OR of women for poor mental functioning was the largest for Japanese women (OR=1.91), followed by for British women (OR=1.45), and then for Finnish women (OR=1.07). Thus, sex differences in physical and mental health was the smallest in the Finnish population. The larger the sex differences in work characteristics, the larger the sex differences in health and the reduction in the sex differences in health after adjustment for work characteristics. These results suggest that egalitarian and gender equal policies may contribute to smaller sex differences in health, through smaller differences in disadvantaged work characteristics between men and women. PMID:21782303
Amygdala subnuclei resting-state functional connectivity sex and estrogen differences.
Engman, Jonas; Linnman, Clas; Van Dijk, Koene R A; Milad, Mohammed R
2016-01-01
The amygdala is a hub in emotional processing, including that of negative affect. Healthy men and women have distinct differences in amygdala responses, potentially setting the stage for the observed sex differences in the prevalence of fear, anxiety, and pain disorders. Here, we examined how amygdala subnuclei resting-state functional connectivity is affected by sex, as well as explored how the functional connectivity is related to estrogen levels. Resting-state functional connectivity was measured using functional magnetic resonance imaging (fMRI) with seeds placed in the left and right laterobasal (LB) and centromedial (CM) amygdala. Sex differences were studied in 48 healthy men and 48 healthy women, matched for age, while the association with estrogen was analyzed in a subsample of 24 women, for whom hormone levels had been assessed. For the hormone analyses, the subsample was further divided into a lower and higher estrogen levels group based on a median split. We found distinct sex differences in the LB and CM amygdala resting-state functional connectivity, as well as preliminary evidence for an association between estrogen levels and connectivity patterns. These results are potentially valuable in explaining why women are more afflicted by conditions of negative affect than are men, and could imply a mechanistic role for estrogen in modulating emotion. Copyright © 2015 Elsevier Ltd. All rights reserved.
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…
Song, Young-Hwan; Kim, Hae Soon; Park, Hae Sook; Jung, Jo Won; Kim, Nam Su; Noh, Chung Il; Hong, Young Mi
2014-01-01
Objective Obesity in adolescence is associated with increased cardiovascular risk. The patterns of obesity and body composition differ between boys and girls. It is uncertain how body composition correlates with the cardiovascular system and whether such correlations differ by sex in adolescents. Methods Body composition (fat-free mass (FFM), adipose mass, waist circumference (WC)) and cardiovascular parameters and functions were studied in 676 healthy Korean adolescents aged 12-16 years. Partial correlation and path analyses were done. Results WC correlated with stroke volume (SV) and cardiac output (CO), systolic blood pressure (SBP) and pulse pressure (PP), cardiac diastolic function (ratio of early to late filling velocity (E/A ratio)), and vascular function (pulse wave velocity (PWV)) in boys. Adipose mass was related to SV, CO, SBP, PP, left ventricular mass (LVM), and PWV in girls – and to E/A ratio in both sexes. FFM affected SV, CO, SBP, and PP in both sexes and LVM in boys. Cardiac systolic functions had no relation with any body composition variable in either sex. Conclusion In adolescence, the interdependence of the cardiovascular system and the body composition differs between sexes. Understanding of those relations is required to control adolescent obesity and prevent adult cardiovascular disease. PMID:24820977
Cognitive function and associated factors among older people in Taiwan: age and sex differences.
Li, Cheng-Lun; Hsu, Hui-Chuan
2015-01-01
The aim of this study was to examine cognitive function and the risk and the protective factors by age and sex among Taiwanese older people. The data were from a nation-representative panel of older people in Taiwan. The participants completing both the 2003 and 2007 waves were included for analysis in this study (n=3228). Descriptive analysis and generalized linear model were applied, and the samples were stratified by age groups and by sex. The factors related to higher cognitive function at the intercept included being younger, male, higher education, and doing unpaid work. At the time slope, the age effect and physical function difficulties would reduce the cognitive function across time, while education and providing informational support would increase the cognitive function across time. There were age- and sex-differences in the factors related to cognitive function, particularly on the working status and social participation. Different health promotion strategies to target these populations should be accordingly developed. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
Beyond sex differences: new approaches for thinking about variation in brain structure and function
Joel, Daphna; Fausto-Sterling, Anne
2016-01-01
In the study of variation in brain structure and function that might relate to sex and gender, language matters because it frames our research questions and methods. In this article, we offer an approach to thinking about variation in brain structure and function that pulls us outside the sex differences formulation. We argue that the existence of differences between the brains of males and females does not unravel the relations between sex and the brain nor is it sufficient to characterize a population of brains. Such characterization is necessary for studying sex effects on the brain as well as for studying brain structure and function in general. Animal studies show that sex interacts with environmental, developmental and genetic factors to affect the brain. Studies of humans further suggest that human brains are better described as belonging to a single heterogeneous population rather than two distinct populations. We discuss the implications of these observations for studies of brain and behaviour in humans and in laboratory animals. We believe that studying sex effects in context and developing or adopting analytical methods that take into account the heterogeneity of the brain are crucial for the advancement of human health and well-being. PMID:26833844
Sex and gender in psychoneuroimmunology research: Past, present and future
Darnall, Beth D.; Suarez, Edward C.
2009-01-01
To date, research suggests that sex and gender impact pathways central to the foci of psychoneuroimmunology (PNI). This review provides a historical perspective on the evolution of sex and gender in psychoneuroimmunology research. Gender and sexually dimorphic pathways may have synergistic effects on health differences in men and women. We provide an overview of the literature of sex and gender differences in brain structure and function, sex steroids, gender role identification, hypothalamic-pituitary-adrenal axis function, genetics, immunology and cytokine response. Specific examples shed light on the importance of attending to sex and gender methodology in PNI research and recommendations are provided. PMID:19272440
Sex and gender in psychoneuroimmunology research: past, present and future.
Darnall, Beth D; Suarez, Edward C
2009-07-01
To date, research suggests that sex and gender impact pathways central to the foci of psychoneuroimmunology (PNI). This review provides a historical perspective on the evolution of sex and gender in psychoneuroimmunology research. Gender and sexually dimorphic pathways may have synergistic effects on health differences in men and women. We provide an overview of the literature of sex and gender differences in brain structure and function, sex steroids, gender role identification, hypothalamic-pituitary-adrenal axis function, genetics, immunology and cytokine response. Specific examples shed light on the importance of attending to sex and gender methodology in PNI research and recommendations are provided.
Sex differences in the mediators of functional disability in Major Depressive Disorder.
Carmona, Nicole E; Subramaniapillai, Mehala; Mansur, Rodrigo B; Cha, Danielle S; Lee, Yena; Fus, Dominika; McIntyre, Roger S
2018-01-01
The aim of this study was to investigate sex differences in discrete domains of psychopathology as mediators of functional disability among individuals with Major Depressive Disorder (MDD). Adults (ages 18-65) with moderate-to-severe MDD (n = 100) and age-, sex-, and education-matched healthy controls (HC; n = 100) participated in a clinical trial validating the THINC-integrated tool, a newly developed cognitive assessment tool for patients with MDD. Variables assessed as possible mediators included depression symptom severity, anxiety symptoms, sleep disturbance, perceived cognitive deficits, and objective cognitive performance. Functional disability was assessed using the total score on the Sheehan Disability Scale. Separate mediation analyses were conducted for men and women. No significant differences were detected between men and women on the assessed domains of psychopathology or functional disability (ps > 0.05). However, the mediation analyses demonstrated different patterns with respect to determinants of functional disability in MDD between men and women. Functional disability was mediated by anxiety (95% CI: -3.17, -0.28) and sleep disturbance (95% CI: -0.69, -0.05) among men and by depressive symptom severity (95% CI: -7.82, -0.32) among women. These preliminary results instantiate the need to dimensionalize psychopathology in MDD. Our results at least in part support the hypothesis that, consistent with the sex differences in the prevalence and illness presentation of MDD, determinants of functional outcomes also differ between men and women, underscoring the need to consider sex differences in order to improve functional outcomes in the treatment of MDD. Copyright © 2017. Published by Elsevier Ltd.
Ratnu, Vikram S.; Emami, Michael R.; Bredy, Timothy W.
2016-01-01
There are inherent biological differences between males and females that contribute to sex differences in brain function and to many sex-specific illnesses and disorders. Traditionally, it has been thought that such differences are largely due to hormonal regulation; however, there are also genetic and epigenetic effects caused by the inheritance and unequal dosage of genes located on the X- and Y-chromosomes. Here we discuss the evidence in favor of a genetic and epigenetic basis for sexually dimorphic behavior, as a consequence of underlying differences in the regulation of genes that drive brain function. A better understanding of sex-specific molecular processes in the brain will provide further insight for the development of novel therapeutic approaches for the treatment of neuropsychiatric disorders characterized by gender/sex differences. PMID:27870402
Sex differences in vascular endothelial function and health in humans: impacts of exercise.
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.
The Variety of Vertebrate Mechanisms of Sex Determination
Trukhina, Antonina V.; Lukina, Natalia A.; Wackerow-Kouzova, Natalia D.; Smirnov, Alexander F.
2013-01-01
The review deals with features of sex determination in vertebrates. The mechanisms of sex determination are compared between fishes, amphibians, reptilians, birds, and mammals. We focus on structural and functional differences in the role of sex-determining genes in different vertebrates. Special attention is paid to the role of estrogens in sex determination in nonmammalian vertebrates. PMID:24369014
The variety of vertebrate mechanisms of sex determination.
Trukhina, Antonina V; Lukina, Natalia A; Wackerow-Kouzova, Natalia D; Smirnov, Alexander F
2013-01-01
The review deals with features of sex determination in vertebrates. The mechanisms of sex determination are compared between fishes, amphibians, reptilians, birds, and mammals. We focus on structural and functional differences in the role of sex-determining genes in different vertebrates. Special attention is paid to the role of estrogens in sex determination in nonmammalian vertebrates.
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 Role Identity, Androgyny, and Sex Role Transcendence: A Sex Role Strain Analysis.
ERIC Educational Resources Information Center
Garnets, Linda; Pleck, Joseph H.
1979-01-01
This paper first reviews three different theoretical constructs concerning the psychological significance of sex-role-related characteristics in personality functioning: sex role identity, androgyny, and sex role transcendence. A new conceptual analysis concerning sex-typing, sex role strain analysis, is presented. Implications of this analysis…
Developmental Sex Differences in the Relation of Neuroanatomical Connectivity to Intelligence
ERIC Educational Resources Information Center
Schmithorst, Vincent J.
2009-01-01
Recent neuroimaging research has shown sex-related differences in the relationship between brain structure and cognitive function. Anatomical studies have shown a greater reliance for cognitive function on white matter structure in adult females, and a greater reliance on gray matter structure in adult males. Functional neuroimaging studies have…
Effects of age and sex on developmental neural networks of visual-spatial attention allocation.
Rubia, Katya; Hyde, Zoe; Halari, Rozmin; Giampietro, Vincent; Smith, Anna
2010-06-01
Compared to our understanding of the functional maturation of brain networks underlying complex cognitive abilities, hardly anything is known of the neurofunctional development of simpler cognitive abilities such as visuo-spatial attention allocation. Furthermore, nothing is known on the effect of gender on the functional development of attention allocation. This study employed event related functional magnetic resonance imaging to investigate effects of age, sex, and sex by age interactions on the brain activation of 63 males and females, between 13 to 38years, during a visual-spatial oddball task. Behaviourally, with increasing age, speed was traded for accuracy, indicative of a less impulsive performance style in older subjects. Increasing age was associated with progressively increased activation in typical areas of selective attention of lateral fronto-striatal and temporo-parietal brain regions. Sex difference analysis showed enhanced activation in right-hemispheric inferior frontal and superior temporal regions in females, and in left-hemispheric inferior temporo-parietal regions in males. Importantly, the age by sex interaction findings showed that these sex-dimorphic patterns of brain activation may be the result of underlying sex differences in the functional maturation of these brain regions, as females had sex-specific progressive age-correlations in the same right inferior fronto-striato-temporal areas, while male-specific age-correlations were in left medial temporal and parietal areas. The findings demonstrate progressive functional maturation of fronto-striato-parieto-temporal networks of the relatively simple function of attention allocation between early adolescence and mid-adulthood. They furthermore show that sex-dimorphic patterns of enhanced reliance on right inferior frontal, striatal and superior temporal regions in females and of left temporo-parietal regions in males during attention allocation may be the result of underlying sex differences in the functional maturation of these brain regions. Copyright 2010 Elsevier Inc. All rights reserved.
Neural, not gonadal, origin of brain sex differences in a gynandromorphic finch.
Agate, Robert J; Grisham, William; Wade, Juli; Mann, Suzanne; Wingfield, John; Schanen, Carolyn; Palotie, Aarno; Arnold, Arthur P
2003-04-15
In mammals and birds, sex differences in brain function and disease are thought to derive exclusively from sex differences in gonadal hormone secretions. For example, testosterone in male mammals acts during fetal and neonatal life to cause masculine neural development. However, male and female brain cells also differ in genetic sex; thus, sex chromosome genes acting within cells could contribute to sex differences in cell function. We analyzed the sexual phenotype of the brain of a rare gynandromorphic finch in which the right half of the brain was genetically male and the left half genetically female. The neural song circuit on the right had a more masculine phenotype than that on the left. Because both halves of the brain were exposed to a common gonadal hormone environment, the lateral differences indicate that the genetic sex of brain cells contributes to the process of sexual differentiation. Because both sides of the song circuit were more masculine than that of females, diffusible factors such as hormones of gonadal or neural origin also likely played a role in sexual differentiation.
Sex differences in the development of brain mechanisms for processing biological motion.
Anderson, L C; Bolling, D Z; Schelinski, S; Coffman, M C; Pelphrey, K A; Kaiser, M D
2013-12-01
Disorders related to social functioning including autism and schizophrenia differ drastically in incidence and severity between males and females. Little is known about the neural systems underlying these sex-linked differences in risk and resiliency. Using functional magnetic resonance imaging and a task involving the visual perception of point-light displays of coherent and scrambled biological motion, we discovered sex differences in the development of neural systems for basic social perception. In adults, we identified enhanced activity during coherent biological motion perception in females relative to males in a network of brain regions previously implicated in social perception including amygdala, medial temporal gyrus, and temporal pole. These sex differences were less pronounced in our sample of school-age youth. We hypothesize that the robust neural circuitry supporting social perception in females, which diverges from males beginning in childhood, may underlie sex differences in disorders related to social processing. © 2013 Elsevier Inc. All rights reserved.
Sex Differences in the Development of Brain Mechanisms for Processing Biological Motion
Anderson, L.C.; Bolling, D.Z.; Schelinski, S.; Coffman, M.C.; Pelphrey, K.A.; Kaiser, M.D.
2013-01-01
Disorders related to social functioning including autism and schizophrenia differ drastically in incidence and severity between males and females. Little is known about the neural systems underlying these sex-linked differences in risk and resiliency. Using functional magnetic resonance imaging and a task involving the visual perception of point-light displays of coherent and scrambled biological motion, we discovered sex differences in the development of neural systems for basic social perception. In adults, we identified enhanced activity during coherent biological motion perception in females relative to males in a network of brain regions previously implicated in social perception including amygdala, medial temporal gyrus, and temporal pole. These sex differences were less pronounced in our sample of school-age youth. We hypothesize that the robust neural circuitry supporting social perception in females, which diverges from males beginning in childhood, may underlie sex differences in disorders related to social processing. PMID:23876243
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.
Masumoto, Taeko; Yamada, Yosuke; Yamada, Minoru; Nakaya, Tomoki; Miyake, Motoko; Watanabe, Yuya; Yoshida, Tsukasa; Yokoyama, Keiichi; Yamagata, Emi; Date, Heiwa; Nanri, Hinako; Komatsu, Mitsuyo; Yoshinaka, Yasuko; Fujiwara, Yoshinori; Okayama, Yasuko; Kimura, Misaka
2015-01-01
Although factors associated with falls might differ between men and women, no large-scale studies were conducted to examine the sex difference of risk factors for falls in Japanese elderly. The purpose of this study was to examine fall risk factors and sex differences among community-dwelling elderly individuals using a complete survey of the geriatric population in Kameoka city. A self-administered questionnaire survey was conducted with 18,231 community-dwelling elderly individuals aged 65 years or over in Kameoka city, Kyoto Prefecture, between July and August 2011, excluding people who were publicly certified with a long-term care need of grade 3 or higher. The questionnaire was individually distributed and collected via mail. Out of 12,159 responders (recovery rate of 72.2%), we analyzed the data of 12,054 elderly individuals who were not certified as having long-term care needs. The questionnaire was composed of basic attributes, a simple screening test for fall risk, the Kihon Check List with 25 items, and the Tokyo Metropolitan Institute of Gerontology (TMIG) index of competence with 13 items. These items were grouped into nine factors: motor function, malnutrition, oral function, houseboundness, forgetfulness, depression, Instrumental Activity of Daily Living (IADL), intellectual activities, and social role. Of all the respondents, 20.8% experienced falls within the last year, and 26.6% were classified as having high fall risk. Fall risk increased with age in both sexes, and risk in all age groups was higher for women than for men. All factors were significantly associated with fall risk in both sexes. After controlling for these factors, a significant relationship was found between fall risk and motor function, malnutrition, oral function, forgetfulness, depression, and IADL in men and motor function, oral function, forgetfulness, depression, and IADL in women. The deterioration of motor function was associated with three-times-higher risk than non-deterioration of motor function. In addition, significant interaction was found in sex×malnutrition, oral function, IADL, and intellectual activities; malnutrition and low oral function were stronger factors in men than in women; and IADL and intellectual activities were stronger factors in women than in men. One in five community-dwelling independent elderly individuals experienced falls in the last year, and one in four had high fall risk. We found a significant relationship between fall risk and the nine factors, particularly deterioration of motor function in both sexes. Sex difference was observed for fall risk factors; therefore, a sex-specific support policy for fall prevention is necessary.
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…
Sex hormones and adult hippocampal neurogenesis: Regulation, implications, and potential mechanisms.
Mahmoud, Rand; Wainwright, Steven R; Galea, Liisa A M
2016-04-01
Neurogenesis within the adult hippocampus is modulated by endogenous and exogenous factors. Here, we review the role of sex hormones in the regulation of adult hippocampal neurogenesis in males and females. The review is framed around the potential functional implications of sex hormone regulation of adult hippocampal neurogenesis, with a focus on cognitive function and mood regulation, which may be related to sex differences in incidence and severity of dementia and depression. We present findings from preclinical studies of endogenous fluctuations in sex hormones relating to reproductive function and ageing, and from studies of exogenous hormone manipulations. In addition, we discuss the modulating roles of sex, age, and reproductive history on the relationship between sex hormones and neurogenesis. Because sex hormones have diverse targets in the central nervous system, we overview potential mechanisms through which sex hormones may influence hippocampal neurogenesis. Lastly, we advocate for a more systematic consideration of sex and sex hormones in studying the functional implications of adult hippocampal neurogenesis. Copyright © 2016 Elsevier Inc. All rights reserved.
Beyond sex differences: new approaches for thinking about variation in brain structure and function.
Joel, Daphna; Fausto-Sterling, Anne
2016-02-19
In the study of variation in brain structure and function that might relate to sex and gender, language matters because it frames our research questions and methods. In this article, we offer an approach to thinking about variation in brain structure and function that pulls us outside the sex differences formulation. We argue that the existence of differences between the brains of males and females does not unravel the relations between sex and the brain nor is it sufficient to characterize a population of brains. Such characterization is necessary for studying sex effects on the brain as well as for studying brain structure and function in general. Animal studies show that sex interacts with environmental, developmental and genetic factors to affect the brain. Studies of humans further suggest that human brains are better described as belonging to a single heterogeneous population rather than two distinct populations. We discuss the implications of these observations for studies of brain and behaviour in humans and in laboratory animals. We believe that studying sex effects in context and developing or adopting analytical methods that take into account the heterogeneity of the brain are crucial for the advancement of human health and well-being. © 2016 The Author(s).
Sekine, Michikazu; Tatsuse, Takashi; Kagamimori, Sadanobu; Chandola, Tarani; Cable, Noriko; Marmot, Michael; Martikainen, Pekka; Lallukka, Tea; Rahkonen, Ossi; Lahelma, Eero
2011-08-01
In general, women report more physical and mental symptoms than men. International comparisons of countries with different welfare state regimes may provide further understanding of the social determinants of sex inequalities in health. This study aims to evaluate (1) whether there are sex inequalities in health functioning as measured by the Short Form 36 (SF-36), and (2) whether work characteristics contribute to the sex inequalities in health among employees from Britain, Finland, and Japan, representing liberal, social democratic, and conservative welfare state regimes, respectively. The participants were 7340 (5122 men and 2218 women) British employees, 2297 (1638 men and 659 women) Japanese employees, and 8164 (1649 men and 6515 women) Finnish employees. All the participants were civil servants aged 40-60 years. We found that more women than men tended to have disadvantaged work characteristics (i.e. low employment grade, low job control, high job demands, and long work hours) but such sex differences were relatively smaller among employees from Finland, where more gender equal policies exist than Britain and Japan. The age-adjusted odds ratio (OR) of women for poor physical functioning was the largest for British women (OR = 2.08), followed by for Japanese women (OR = 1.72), and then for Finnish women (OR = 1.51). The age-adjusted OR of women for poor mental functioning was the largest for Japanese women (OR = 1.91), followed by for British women (OR = 1.45), and then for Finnish women (OR = 1.07). Thus, sex differences in physical and mental health was the smallest in the Finnish population. The larger the sex differences in work characteristics, the larger the sex differences in health and the reduction in the sex differences in health after adjustment for work characteristics. These results suggest that egalitarian and gender equal policies may contribute to smaller sex differences in health, through smaller differences in disadvantaged work characteristics between men and women. Copyright © 2011 Elsevier Ltd. All rights reserved.
A Lateralization of Function Approach to Sex Differences in Spatial Ability: A Reexamination
ERIC Educational Resources Information Center
Rilea, Stacy L.
2008-01-01
The current study assessed the lateralization of function hypothesis (Rilea, S. L., Roskos-Ewoldsen, B., & Boles, D. (2004). "Sex differences in spatial ability: A lateralization of function approach." "Brain and Cognition," 56, 332-343) which suggested that it was the interaction of brain organization and the type of spatial task that led to sex…
Sexing California Clapper Rails using morphological measurements
Overton, Cory T.; Casazza, Michael L.; Takekawa, John Y.; Rohmer, Tobias M.
2009-01-01
California Clapper Rails (Rallus longirostris obsoletus) have monomorphic plumage, a trait that makes identification of sex difficult without extensive behavioral observation or genetic testing. Using 31 Clapper Rails (22 females, 9 males), caught in south San Francisco Bay, CA, and using easily measurable morphological characteristics, we developed a discriminant function to distinguish sex. We then validated this function on 33 additional rails. Seven morphological measurements were considered, resulting in three which were selected in the discriminate function: culmen length, tarsometatarsus length, and flat wing length. We had no classification errors for the development or testing datasets either with resubstitution or cross-validation procedures. Male California Clapper Rails were 6-22% larger than females for individual morphological traits, and the largest difference was in body mass. Variables in our discriminant function closely match variables developed for sexing Clapper Rails of Gulf Coast populations. However, a universal discriminant function to sex all Clapper Rail subspecies is not likely because of large and inconsistent differences in morphological traits among subspecies.
Motor Skill Acquisition: A Function of Gender or Sex-Role?
ERIC Educational Resources Information Center
Lombardo, John P.; And Others
Previous research has found that males perform better than females on the pursuit rotor. To examine whether males and females with different sex role orientations would perform differently on a motor task, 120 students (classified as androgynous, traditional sex role, cross-sexed, or undifferentiated, based on scores on the Personal Attributes…
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 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 NSAID-induced perturbation of human intestinal barrier function and microbiota.
Edogawa, Shoko; Peters, Stephanie A; Jenkins, Gregory D; Gurunathan, Sakteesh V; Sundt, Wendy J; Johnson, Stephen; Lennon, Ryan J; Dyer, Roy B; Camilleri, Michael; Kashyap, Purna C; Farrugia, Gianrico; Chen, Jun; Singh, Ravinder J; Grover, Madhusudan
2018-06-13
Intestinal barrier function and microbiota are integrally related and play critical roles in maintenance of host physiology. Sex is a key biologic variable for several disorders. Our aim was to determine sex-based differences in response to perturbation and subsequent recovery of intestinal barrier function and microbiota in healthy humans. Twenty-three volunteers underwent duodenal biopsies, mucosal impedance, and in vivo permeability measurement. Permeability testing was repeated after administration of indomethacin, then 4 to 6 wk after its discontinuation. Duodenal and fecal microbiota composition was determined using 16S rRNA amplicon sequencing. Healthy women had lower intestinal permeability and higher duodenal and fecal microbial diversity than healthy men. Intestinal permeability increases after indomethacin administration in both sexes. However, only women demonstrated decreased fecal microbial diversity, including an increase in Prevotella abundance, after indomethacin administration. Duodenal microbiota composition did not show sex-specific changes. The increase in permeability and microbiota changes normalized after discontinuation of indomethacin. In summary, women have lower intestinal permeability and higher microbial diversity. Intestinal permeability is sensitive to perturbation but recovers to baseline. Gut microbiota in women is sensitive to perturbation but appears to be more stable in men. Sex-based differences in intestinal barrier function and microbiome should be considered in future studies.-Edogawa, S., Peters, S. A., Jenkins, G. D., Gurunathan, S. V., Sundt, W. J., Johnson, S., Lennon, R. J., Dyer, R. B., Camilleri, M., Kashyap, P. C., Farrugia, G., Chen, J., Singh, R. J., Grover, M. Sex differences in NSAID-induced perturbation of human intestinal barrier function and microbiota.
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.
Kelly, Philip A; Viding, Essi; Puetz, Vanessa B; Palmer, Amy L; Mechelli, Andrea; Pingault, Jean-Baptiste; Samuel, Sophie; McCrory, Eamon J
2015-11-01
While maltreatment is known to impact social and emotional functioning, threat processing, and neural structure, the potentially dimorphic influence of sex on these outcomes remains relatively understudied. We investigated sex differences across these domains in a large community sample of children aged 10 to 14 years (n = 122) comprising 62 children with verified maltreatment experience and 60 well-matched nonmaltreated peers. The maltreated group relative to the nonmaltreated comparison group exhibited poorer social and emotional functioning (more peer problems and heightened emotional reactivity). Cognitively, they displayed a pattern of attentional avoidance of threat in a visual dot-probe task. Similar patterns were observed in males and females in these domains. Reduced gray matter volume was found to characterize the maltreated group in the medial orbitofrontal cortex, bilateral middle temporal lobes, and bilateral supramarginal gyrus; sex differences were observed only in the supramarginal gyrus. In addition, a disordinal interaction between maltreatment exposure and sex was found in the postcentral gyrus. Finally, attentional avoidance to threat mediated the relationship between maltreatment and emotional reactivity, and medial orbitofrontal cortex gray matter volume mediated the relationship between maltreatment and peer functioning. Similar mediation patterns were observed across sexes. This study highlights the utility of combining multiple levels of analysis when studying the "latent vulnerability" engendered by childhood maltreatment and yields tentative findings regarding a neural basis of sex differences in long-term outcomes for maltreated children.
Executive functions in men and postmenopausal women.
Castonguay, Nathalie; Lussier, Maxime; Bugaiska, Aurélia; Lord, Catherine; Bherer, Louis
2015-01-01
This study was designed to assess sex differences in older adults (55-65 years old) in executive functions and to examine the influence of hormone therapy (HT) in postmenopausal women. We have assessed task performance in memory, visuospatial, and executive functions in 29 women using HT, 29 women who never used HT, and 30 men. Men outperformed never users in task switching and updating. HT users outperformed never users in updating. HT users outperformed never users and men in visual divided attention. The present study support previous findings that sex and HT impact cognition and bring new insights on sex and HT-related differences in executive functions.
Sex-related differences in striatal dopaminergic system after traumatic brain injury.
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.
Bala, Gustav; Katić, Ratko
2009-12-01
The study included a sample of 333 preschool children (162 male and 171 female) at the time of school enrolment. Study subjects were recruited from the population of children in kindergartens in the cities of Novi Sad, Sombor, Sremska Mitrovica and Backa Palanka (Province of Voivodina, Serbia). Eight anthropometric variables, seven motor variables and one cognitive variable were analyzed to identify quantitative and qualitative sex differences in anthropometric characteristics, motor and cognitive functioning. Study results showed statistically significant sex differences in anthropometric characteristics and motor abilities in favor of male children, whereas no such difference was recorded in cognitive functioning. Sex differences found in morphological and motor spaces contributed to structuring proper general factors according to space and sex. Somewhat stronger structures were observed in male children. The cognitive aspect of functioning yielded better correlation with motor functioning in female than in male children. Motor functioning correlated better with morphological growth and development in male children, whereas cognitive functioning was relatively independent. These results are not fully in accordance with the current concept of general conditions in preschool children, nor they fully confirm the theory of integral development of children, hence they should be re-examined in future studies. Although these study results cannot be applied to sports practice in general, since we believe that it is too early for preschool children to take up sports and sport competitions, they are relevant for pointing to the need of developing general motor ability and motor behavior in preschool children.
Li, Wei; Qiu, Qi; Sun, Lin; Yue, Ling; Wang, Tao; Li, Xia; Xiao, Shifu
2017-01-01
Sex differences in Alzheimer's disease and mild cognitive impairment have been well recognized. However, sex differences in cognitive function and obesity in cognitively normal aging Chinese Han population have not attracted much attention. The aim of this study was to investigate the relationship between sex, obesity, and cognitive function in an elderly Chinese population with normal cognitive function. A total of 228 cognitively normal aging participants (males/females =93/135) entered this study. Their general demographic information (sex, age, and education) was collected by standardized questionnaire. Apolipoprotein E (APOE) genotype and serum lipid levels were measured. The Montreal Cognitive Assessment (MoCA) was used to assess participants' cognitive function. The prevalence of obesity in elderly women (18/133, 13.5%) was significantly higher than that in men (5/92, 5.4%, P =0.009). Regression analyses showed that obesity was associated with drinking alcohol (OR =13.695, P =0.045) and triglyceride (OR =1.436, P =0.048) in women and limited to low-density lipoprotein (OR =11.829, P =0.023) in men. Women performed worse on the naming score for MoCA than men ( P <0.01). Stepwise linear regression analysis showed that education ( t =3.689, P <0.001) and smoking ( t =2.031, P =0.045) were related to the score of naming in female, while high-density lipoprotein ( t =-2.077, P =0.041) was related to the score of naming in male; however, no correlation was found between body mass index and cognitive function in both male and female ( P >0.05). Our finding suggests that there are significant sex differences in obesity and specific cognitive domains in aging Chinese Han population with normal cognitive function.
A neuropsychological study of older adult first-time sex offenders.
Rodriguez, Marcelo; Boyce, Philip; Hodges, John
2017-04-01
The issue of whether sex offenders have cognitive deficits remains controversial. The objective of this study was to compare the neuropsychological function of older adult first time sex-offenders (FTSO), who had not previously been charged with a sexual offence prior to the age of 50, to historical long-term sex offenders (HSO) and non-sex offenders (NSO). The hypotheses were (a) that FTSO would demonstrate greater deficits in executive function, decision-making, and memory compared to non-sex offenders; and (b) the HSOs would present similar neuropsychological deficits to non-sex offenders. A battery of neuropsychological measures was administered to 100 participants comprising 32 FTSOs, 36 HSOs, and 32 NSOs. Both FTSOs and HSOs showed significant impairment on tests of executive function (including verbal fluency, trail-making, and the Hayling test of response inhibition) as well as on tests of verbal and verbal memory compared to NSOs; however, there was no difference between the two sex offender groups. Older adult sex offenders, overall, demonstrated poorer neuropsychological performance than older adult non-sex offenders did, although there was no difference between older first-time and historical offenders. Cognitive deficits may increase the risk of sexual offending due to impaired capacity in self-regulation, planning, judgment, and inhibition. A proportion of older adult sex offenders may be harboring acquired frontal lobe pathology.
Anderson, Jennifer L.; Rodríguez Marí, Adriana; Braasch, Ingo; Amores, Angel; Hohenlohe, Paul; Batzel, Peter; Postlethwait, John H.
2012-01-01
Within vertebrates, major sex determining genes can differ among taxa and even within species. In zebrafish (Danio rerio), neither heteromorphic sex chromosomes nor single sex determination genes of large effect, like Sry in mammals, have yet been identified. Furthermore, environmental factors can influence zebrafish sex determination. Although progress has been made in understanding zebrafish gonad differentiation (e.g. the influence of germ cells on gonad fate), the primary genetic basis of zebrafish sex determination remains poorly understood. To identify genetic loci associated with sex, we analyzed F2 offspring of reciprocal crosses between Oregon *AB and Nadia (NA) wild-type zebrafish stocks. Genome-wide linkage analysis, using more than 5,000 sequence-based polymorphic restriction site associated (RAD-tag) markers and population genomic analysis of more than 30,000 single nucleotide polymorphisms in our *ABxNA crosses revealed a sex-associated locus on the end of the long arm of chr-4 for both cross families, and an additional locus in the middle of chr-3 in one cross family. Additional sequencing showed that two SNPs in dmrt1 previously suggested to be functional candidates for sex determination in a cross of ABxIndia wild-type zebrafish, are not associated with sex in our AB fish. Our data show that sex determination in zebrafish is polygenic and that different genes may influence sex determination in different strains or that different genes become more important under different environmental conditions. The association of the end of chr-4 with sex is remarkable because, unique in the karyotype, this chromosome arm shares features with known sex chromosomes: it is highly heterochromatic, repetitive, late replicating, and has reduced recombination. Our results reveal that chr-4 has functional and structural properties expected of a sex chromosome. PMID:22792396
Sex Differences in Human Fatigability: Mechanisms and Insight to Physiological Responses
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
Sex-specific lateralization of event-related potential effects during mental rotation of polygons.
Pellkofer, Julia; Jansen, Petra; Heil, Martin
2014-08-06
Mental rotation performance has been found to produce one of the largest sex differences in cognition. Many theories suggest that this effect should be accompanied by a sex difference in functional cerebral asymmetry, but empirical data are more than equivocal probably because of (a) the use of inappropriate stimuli and (b) insufficient power of most neurophysiological studies. Therefore, sex differences in mental rotation of polygons were investigated in 122 adults. Men outperformed women on mental rotation speed (as well as on response time and accuracy). On the basis of the electrophysiological brain correlates of mental rotation, we observed a bilateral brain activity for men, whereas women's brain activity was clearly lateralized toward the left hemisphere if and only if mental rotation was involved. Thus, sex differences in functional cerebral asymmetry can indeed be observed if appropriate stimuli are used in a sufficiently large sample.
Spatial ability as a predictor of math achievement: the importance of sex and handedness patterns.
Casey, M B; Pezaris, E; Nuttall, R L
1992-01-01
In accordance with major theories of handedness and brain organization, differential predictors for math achievement were found as a function of sex and handedness subgroups among eighth graders. Although there was no difference in absolute levels of performance as a function of either sex or handedness, predictive structures did differ. Regression analyses showed that spatial ability predicts math achievement for: (1) girls with anomalous dominance (non-right-handers and right-handers with non-right-handed relatives), and (2) all boys (independent of handedness group). In contrast, for the standard dominance girls who are right-handed with all right-handed relatives (considered strongly left-hemisphere dominant for language), spatial ability did not predict for math achievement. These findings occurred, even when scholastic aptitude and verbal achievement factors were controlled. It was concluded that further studies of sex differences in math achievement should consider subgroup differences within the sexes, based on handedness patterns.
Finkel, Deborah; Ernsth-Bravell, Marie; Pedersen, Nancy L
2015-09-01
To determine the extent to which genetic and environmental factors contribute to individual and gender differences in aging of functional ability. Twenty assessments of functional ability are collected as part of the longitudinal Swedish Adoption/Twin Study of Aging from 859 twins aged 50-88 at the first wave. Participants completed up to 6 assessments covering a 19-year period. Factor analysis was used to create 3 factors: flexibility, fine motor skills, and balance. Latent growth curve analysis demonstrated increasing disability and variability after age 70. For flexibility, results indicated significant sex differences in mean change trajectories but no sex differences in components of variance. No sex differences were found for fine motor movement. For balance, there were no sex differences in mean change trajectories; however, there was significant genetic variance for changes in balance in women after age 70 but not for men. Although idiosyncratic environmental influences account for a large part of increasing variance, correlated and shared rearing environmental effects were also evident. Thus, both microenvironmental (individual) and macroenvironmental (family and cultural) effects, as well as genetic factors, affect maintenance of functional ability in late adulthood. © The Author 2014. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Grabowska, Anna
2017-01-02
A substantial number of studies provide evidence documenting a variety of sex differences in the brain. It remains unclear whether sexual differentiation at the neural level is related to that observed in daily behavior, cognitive function, and the risk of developing certain psychiatric and neurological disorders. Some investigators have questioned whether the brain is truly sexually differentiated and support this view with several arguments including the following: (1) brain structural or functional differences are not necessarily reflected in appropriate differences at the behavioral level, which might suggest that these two phenomena are not linked to each other; and (2) sex-related differences in the brain are rather small and concern features that significantly overlap between males and females. This review polemicizes with those opinions and presents examples of sex-related local neural differences underpinning a variety of sex differences in behaviors, skills, and cognitive/emotional abilities. Although male/female brain differentiation may vary in pattern and scale, nonetheless, in some respects (e.g., relative local gray matter volumes) it can be substantial, taking the form of sexual dimorphism and involving large areas of the brain (the cortex in particular). A significant part of this review is devoted to arguing that some sex differences in the brain may serve to prevent (in the case where they are maladaptive), rather than to produce, differences at the behavioral/skill level. Specifically, some differences might result from compensatory mechanisms aimed at maintaining similar intellectual capacities across the sexes, despite the smaller average volume of the brain in females compared with males. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
(Putative) Sex differences in neuroimmune modulation of memory
Tronson, Natalie C.; Collette, Katie M.
2016-01-01
The neuroimmune system is significantly sexually dimorphic, with sex differences evident in the number and activation states of microglia, in the activation of astrocytes, and in cytokine release and function. Neuroimmune cells and signaling are now recognized as critical for many neural functions throughout the lifespan, including synaptic plasticity and memory function. Here we address the question of how cytokines, astrocytes, and microglia contribute to memory, and specifically how neuroimmune modulation of memory differentially affects males and females. Understanding sex differences in both normal memory processes and dysregulation of memory in psychiatric and neurological disorders is critical for developing treatment and preventive strategies for memory disorders that are effective for both men and women. PMID:27870428
Sex Differences in Social Perception in Children with ASD
ERIC Educational Resources Information Center
Coffman, M. C.; Anderson, L. C.; Naples, A. J.; McPartland, J. C.
2015-01-01
Autism spectrum disorder (ASD) is more common in males than females. An underrepresentation of females in the ASD literature has led to limited knowledge of differences in social function across the sexes. Investigations of face perception represent a promising target for understanding variability in social functioning between males and females.…
FMRI to probe sex-related differences in brain function with multitasking
Tschernegg, Melanie; Neuper, Christa; Schmidt, Reinhold; Wood, Guilherme; Kronbichler, Martin; Fazekas, Franz; Enzinger, Christian
2017-01-01
Background Although established as a general notion in society, there is no solid scientific foundation for the existence of sex-differences in multitasking. Reaction time and accuracy in dual task conditions have an inverse relationship relative to single task, independently from sex. While a more disseminated network, parallel to decreasing accuracy and reaction time has been demonstrated in dual task fMRI studies, little is known so far whether there exist respective sex-related differences in activation. Methods We subjected 20 women (mean age = 25.45; SD = 5.23) and 20 men (mean age = 27.55; SD = 4.00) to a combined verbal and spatial fMRI paradigm at 3.0T to assess sex-related skills, based on the assumption that generally women better perform in verbal tasks while men do better in spatial tasks. We also obtained behavioral tests for verbal and spatial intelligence, attention, executive functions, and working memory. Results No differences between women and men were observed in behavioral measures of dual-tasking or cognitive performance. Generally, brain activation increased with higher task load, mainly in the bilateral inferior and prefrontal gyri, the anterior cingulum, thalamus, putamen and occipital areas. Comparing sexes, women showed increased activation in the inferior frontal gyrus in the verbal dual-task while men demonstrated increased activation in the precuneus and adjacent visual areas in the spatial task. Conclusion Against the background of equal cognitive and behavioral dual-task performance in both sexes, we provide first evidence for sex-related activation differences in functional networks for verbal and spatial dual-tasking. PMID:28759619
FMRI to probe sex-related differences in brain function with multitasking.
Tschernegg, Melanie; Neuper, Christa; Schmidt, Reinhold; Wood, Guilherme; Kronbichler, Martin; Fazekas, Franz; Enzinger, Christian; Koini, Marisa
2017-01-01
Although established as a general notion in society, there is no solid scientific foundation for the existence of sex-differences in multitasking. Reaction time and accuracy in dual task conditions have an inverse relationship relative to single task, independently from sex. While a more disseminated network, parallel to decreasing accuracy and reaction time has been demonstrated in dual task fMRI studies, little is known so far whether there exist respective sex-related differences in activation. We subjected 20 women (mean age = 25.45; SD = 5.23) and 20 men (mean age = 27.55; SD = 4.00) to a combined verbal and spatial fMRI paradigm at 3.0T to assess sex-related skills, based on the assumption that generally women better perform in verbal tasks while men do better in spatial tasks. We also obtained behavioral tests for verbal and spatial intelligence, attention, executive functions, and working memory. No differences between women and men were observed in behavioral measures of dual-tasking or cognitive performance. Generally, brain activation increased with higher task load, mainly in the bilateral inferior and prefrontal gyri, the anterior cingulum, thalamus, putamen and occipital areas. Comparing sexes, women showed increased activation in the inferior frontal gyrus in the verbal dual-task while men demonstrated increased activation in the precuneus and adjacent visual areas in the spatial task. Against the background of equal cognitive and behavioral dual-task performance in both sexes, we provide first evidence for sex-related activation differences in functional networks for verbal and spatial dual-tasking.
Sex differences in chronic stress effects on cognition in rodents
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
ERIC Educational Resources Information Center
Kopper, Beverly A.
1993-01-01
Investigated relationship of gender, sex role identity, Type A behavior to multiple dimensions of anger expression and mental health functioning among 407 female and 222 male college students. Found significant multivariate effects for sex role and behavior pattern type for anger expression. Significant gender differences were not observed.…
Sex differences during humor appreciation in child-sibling pairs.
Vrticka, Pascal; Neely, Michelle; Walter Shelly, Elizabeth; Black, Jessica M; Reiss, Allan L
2013-01-01
The developmental origin of sex differences in adult brain function is poorly understood. Elucidating neural mechanisms underlying comparable cognitive functionality in both children and adults is required to address this gap. Humor appreciation represents a particularly relevant target for such developmental research because explanatory theories apply across the life span, and underlying neurocircuitry shows sex differences in adults. As a positive mood state, humor is also of interest due to sex differences in rates of depression, a disorder afflicting twice as many women as men. In this study, we employed functional magnetic resonance imaging (fMRI) to investigate brain responses to funny versus positive (and neutral) video clips in 22 children, ages 6-13 years, including eight sibling-pairs. Our data revealed increased activity to funny clips in bilateral temporo-occipital cortex, midbrain, and amygdala in girls. Conversely, we found heightened activation to positive clips in bilateral inferior parietal lobule, fusiform gyrus, inferior frontal gyrus, amygdala, and ventromedial prefrontal cortex in boys. Many of these effects persisted when looking at sibling-pairs only. We interpret such findings as reflecting the presence of early sex divergence in reward saliency or expectation and stimulus relevance attribution. These findings are discussed in the context of evolutionary and developmental theories of humor function.
Sex-related shape dimorphism in the human radiocarpal and midcarpal joints.
Kivell, Tracy L; Guimont, Isabelle; Wall, Christine E
2013-01-01
Previous research has revealed significant size differences between human male and female carpal bones but it is unknown if there are significant shape differences as well. This study investigated sex-related shape variation and allometric patterns in five carpal bones that make up the radiocarpal and midcarpal joints in modern humans. We found that many aspects of carpal shape (76% of all variables quantified) were similar between males and females, despite variation in size. However, 10 of the shape ratios were significantly different between males and females, with at least one significant shape difference observed in each carpal bone. Within-sex standard major axis regressions (SMA) of the numerator (i.e., the linear variables) on the denominator (i.e., the geometric mean) for each significantly different shape ratio indicated that most linear variables scaled with positive allometry in both males and females, and that for eight of the shape ratios, sex-related shape variation is associated with statistically similar sex-specific scaling relationships. Only the length of the scaphoid body and the height of the lunate triquetrum facet showed a significantly higher SMA slope in females compared with males. These findings indicate that the significant differences in the majority of the shape ratios are a function of subtle (i.e., not statistically significant) scaling differences between males and females. There are a number of potential developmental, functional, and evolutionary factors that may cause sex-related shape differences in the human carpus. The results highlight the potential for subtle differences in scaling to result in functionally significant differences in shape. Copyright © 2012 Wiley Periodicals, Inc.
A lateralization of function approach to sex differences in spatial ability: a reexamination.
Rilea, Stacy L
2008-07-01
The current study assessed the lateralization of function hypothesis (Rilea, S. L., Roskos-Ewoldsen, B., & Boles, D. (2004). Sex differences in spatial ability: A lateralization of function approach. Brain and Cognition, 56, 332-343) which suggested that it was the interaction of brain organization and the type of spatial task that led to sex differences in spatial ability. A second purpose was to evaluate explanations for their unexpected findings on the mental rotation task. In Experiment 1, participants completed the Water Level, Paper Folding, and mental rotation tasks (using an object-based or self-based perspective), presented bilaterally. Sex differences were only observed on the Water Level Task; a right hemisphere advantage was observed on Water Level and mental rotation tasks. In Experiment 2, a human stick figure or a polygon was mentally rotated. Men outperformed women when rotating polygons, but not when rotating stick figures. Men demonstrated a right hemisphere advantage when rotating polygons; women showed no hemisphere differences for either stimulus. Thus, hemisphere processing, task complexity, and stimulus type may influence performance for men and women across different spatial measures.
Multifaceted origins of sex differences in the brain
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
Why women see differently from the way men see? A review of sex differences in cognition and sports
Li, Rena
2014-01-01
The differences of learning and memory between males and females have been well documented and confirmed by both human and animal studies. The sex differences in cognition started from early stage of neuronal development and last through entire life span. The major biological basis of the gender-dependent cognitive activity includes two major components: sex hormone and sex-related characteristics, such as sex-determining region of the Y chromosome (SRY) protein. However, the knowledge of how much biology of sex contributes to normal cognitive function and elite athletes in various sports are still pretty limited. In this review, we will be focusing on sex differences in spatial learning and memory – especially the role of male- and female-type cognitive behaviors in sports. PMID:25520851
Why women see differently from the way men see? A review of sex differences in cognition and sports.
Li, Rena
2014-09-01
The differences of learning and memory between males and females have been well documented and confirmed by both human and animal studies. The sex differences in cognition started from early stage of neuronal development and last through entire life span. The major biological basis of the gender-dependent cognitive activity includes two major components: sex hormone and sex-related characteristics, such as sex-determining region of the Y chromosome (SRY) protein. However, the knowledge of how much biology of sex contributes to normal cognitive function and elite athletes in various sports are still pretty limited. In this review, we will be focusing on sex differences in spatial learning and memory - especially the role of male- and female-type cognitive behaviors in sports.
Sex differences in visuospatial abilities persist during induced hypogonadism
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 the current circulating sex steroid environment. Thus sex differences in visuospatial performance in adulthood could reflect early developmental effects of sex steroid exposure or other environmental exposures differing across the sexes as our data confirm that these differences are independent of circulating estradiol or testosterone levels in men and women. PMID:26719236
Sex differences in visuospatial abilities persist during induced hypogonadism.
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 visuospatial performance in adulthood could reflect early developmental effects of sex steroid exposure or other environmental exposures differing across the sexes as our data confirm that these differences are independent of circulating estradiol or testosterone levels in men and women. Published by Elsevier Ltd.
2013-01-01
Young female athletes experience a higher incidence of ligament injuries than their male counterparts, females experience a higher incidence of joint hypermobility syndrome (a risk factor for osteoarthritis development), and post-menopausal females experience a higher prevalence of osteoarthritis than age-matched males. These observations indicate that fluctuating sex hormone levels in young females and loss of ovarian sex hormone production due to menopause likely contribute to observed sex differences in knee joint function and risk for loss of function. In studies of osteoarthritis, however, there is a general lack of appreciation for the heterogeneity of hormonal control in both women and men. Progress in this field is limited by the relatively few preclinical osteoarthritis models, and that most of the work with established models uses only male animals. To elucidate sex differences in osteoarthritis, it is important to examine sex hormone mechanisms in cells from knee tissues and the sexual dimorphism in the role of inflammation at the cell, tissue, and organ levels. There is a need to determine if the risk for loss of knee function and integrity in females is restricted to only the knee or if sex-specific changes in other tissues play a role. This paper discusses these gaps in knowledge and suggests remedies. PMID:23374322
Absence of sex differences in mental rotation performance in autism spectrum disorder.
Rohde, Melanie S; Georgescu, Alexandra L; Vogeley, Kai; Fimmers, Rolf; Falter-Wagner, Christine M
2017-08-01
Mental rotation is one of the most investigated cognitive functions showing consistent sex differences. The 'Extreme Male Brain' hypothesis attributes the cognitive profile of individuals with autism spectrum disorder to an extreme version of the male cognitive profile. Previous investigations focused almost exclusively on males with autism spectrum disorder with only limited implications for affected females. This study is the first testing a sample of 12 female adults with high-functioning autism spectrum disorder compared to 14 males with autism spectrum disorder, 12 typically developing females and 14 typically developing males employing a computerised version of the mental rotation test. Reaction time and accuracy served as dependent variables. Their linear relationship with degree of rotation allows separation of rotational aspects of the task, indicated by slopes of the psychometric function, and non-rotational aspects, indicated by intercepts of the psychometric function. While the typical and expected sex difference for rotational task aspects was corroborated in typically developing individuals, no comparable sex difference was found in autism spectrum disorder individuals. Autism spectrum disorder and typically developing individuals did not differ in mental rotation performance. This finding does not support the extreme male brain hypothesis of autism.
Sugiura, Lisa; Ojima, Shiro; Matsuba-Kurita, Hiroko; Dan, Ippeita; Tsuzuki, Daisuke; Katura, Takusige; Hagiwara, Hiroko
2015-10-01
Previous neuroimaging studies in adults have revealed that first and second languages (L1/L2) share similar neural substrates, and that proficiency is a major determinant of the neural organization of L2 in the lexical-semantic and syntactic domains. However, little is known about neural substrates of children in the phonological domain, or about sex differences. Here, we conducted a large-scale study (n = 484) of school-aged children using functional near-infrared spectroscopy and a word repetition task, which requires a great extent of phonological processing. We investigated cortical activation during word processing, emphasizing sex differences, to clarify similarities and differences between L1 and L2, and proficiency-related differences during early L2 learning. L1 and L2 shared similar neural substrates with decreased activation in L2 compared to L1 in the posterior superior/middle temporal and angular/supramarginal gyri for both sexes. Significant sex differences were found in cortical activation within language areas during high-frequency word but not during low-frequency word processing. During high-frequency word processing, widely distributed areas including the angular/supramarginal gyri were activated in boys, while more restricted areas, excluding the angular/supramarginal gyri were activated in girls. Significant sex differences were also found in L2 proficiency-related activation: activation significantly increased with proficiency in boys, whereas no proficiency-related differences were found in girls. Importantly, cortical sex differences emerged with proficiency. Based on previous research, the present results indicate that sex differences are acquired or enlarged during language development through different cognitive strategies between sexes, possibly reflecting their different memory functions. © 2015 Wiley Periodicals, Inc.
Selective sex differences in declarative memory.
Maitland, Scott B; Herlitz, Agneta; Nyberg, Lars; Bäckman, Lars; Nilsson, Lars-Göran
2004-10-01
Sex invariance of a six-factor, higher order model of declarative memory (two second-order factors: episodic and semantic memory; and four first-order factors: recall, recognition, fluency, and knowledge) was established for 1,796 participants (35-85 years). Metric invariance of first- and second-order factor loadings across sex was demonstrated. At the second-order level, a female advantage was observed for both episodic and semantic memory. At the first-order level, sex differences in episodic memory were apparent for both recall and recognition, whereas the differences in semantic memory were driven by a female superiority in fluency. Additional tests of sex differences in three age groups (35-50, 55-65, and 70-85 years of age) indicated that the female superiority in declarative memory diminished with advancing age. The factor-specific sex differences are discussed in relation to sex differences in hippocampal function.
Endogenous sex hormones and cognitive function in the elderly.
Boss, Lisa; Kang, Duck-Hee; Bergstrom, Nancy; Leasure, J Leigh
2015-08-01
Estrogen and testosterone may influence cognitive function in the older adult, but the relationship between sex hormones and cognitive function is complex. To examine associations of sex hormones and cognitive function among older adults ≥65 years old. Using a cross-sectional research design, data were collected once from 71 elderly (mean age 86.4 years). Global cognitive function and executive function were measured with standardized instruments, and saliva samples were collected for salivary estradiol and testosterone. Estradiol was significantly and positively correlated with global cognitive function in men only (r = 0.54, p < 0.05). Testosterone was not significantly correlated with global cognitive function or executive function in either gender. Associations between sex hormones and cognitive function were mostly non-significant. However, higher estradiol was significantly correlated with better global cognitive function in men, suggesting gender-specific differences. Along with sex hormones, other comorbidity may need to be assessed together in relation to cognitive function in the elderly. Accordingly, clinicians play an important role in educating and promoting beneficial actions to preserve cognitive function.
Linked Sex Differences in Cognition and Functional Connectivity in Youth.
Satterthwaite, Theodore D; Wolf, Daniel H; Roalf, David R; Ruparel, Kosha; Erus, Guray; Vandekar, Simon; Gennatas, Efstathios D; Elliott, Mark A; Smith, Alex; Hakonarson, Hakon; Verma, Ragini; Davatzikos, Christos; Gur, Raquel E; Gur, Ruben C
2015-09-01
Sex differences in human cognition are marked, but little is known regarding their neural origins. Here, in a sample of 674 human participants ages 9-22, we demonstrate that sex differences in cognitive profiles are related to multivariate patterns of resting-state functional connectivity MRI (rsfc-MRI). Males outperformed females on motor and spatial cognitive tasks; females were faster in tasks of emotion identification and nonverbal reasoning. Sex differences were also prominent in the rsfc-MRI data at multiple scales of analysis, with males displaying more between-module connectivity, while females demonstrated more within-module connectivity. Multivariate pattern analysis using support vector machines classified subject sex on the basis of their cognitive profile with 63% accuracy (P < 0.001), but was more accurate using functional connectivity data (71% accuracy; P < 0.001). Moreover, the degree to which a given participant's cognitive profile was "male" or "female" was significantly related to the masculinity or femininity of their pattern of brain connectivity (P = 2.3 × 10(-7)). This relationship was present even when considering males and female separately. Taken together, these results demonstrate for the first time that sex differences in patterns of cognition are in part represented on a neural level through divergent patterns of brain connectivity. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.
ERIC Educational Resources Information Center
Reinhardt, Vanessa P.; Wetherby, Amy M.; Schatschneider, Christopher; Lord, Catherine
2015-01-01
Despite consistent and substantive research documenting a large male to female ratio in Autism Spectrum Disorder (ASD), only a modest body of research exists examining sex differences in characteristics. This study examined sex differences in developmental functioning and early social communication in children with ASD as compared to children with…
The trouble with sex differences.
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.
ERIC Educational Resources Information Center
Bos, Henny M. W.; Sandfort, Theo G. M.; de Bruyn, Eddy H.; Hakvoort, Esther M.
2008-01-01
The authors examined whether 13- to 15-year-old adolescents who experience feelings of same-sex attraction (SSA) differ from those without such feelings in the quality of relationships with parents, peers, and class mentors and in psychosocial functioning (health status and school performance). The authors also assessed whether differences in …
Cecal microbiome divergence of broiler chickens by sex and body weight.
Lee, Kyu-Chan; Kil, Dong Yong; Sul, Woo Jun
2017-12-01
The divergence of gut bacterial community on broiler chickens has been reported as potentially possible keys to enhancing nutrient absorption, immune systems, and increasing poultry health and performance. Thus, we compared cecal bacterial communities and functional predictions by sex and body weight regarding the association between cecal microbiota and chicken growth performance. In this study, a total of 12 male and 12 female 1-day-old broiler chickens were raised for 35 days in 2 separate cages. Chickens were divided into 3 subgroups depending on body weight (low, medium, and high) by each sex. We compared chicken cecal microbiota compositions and its predictive functions by sex and body weight difference. We found that bacterial 16S rRNA genes were classified as 3 major phyla (Bacteroidetes, Firmicutes, and Proteobacteria), accounting for > 98% of the total bacterial community. The profiling of different bacterial taxa and predictive metagenome functions derived from 16S rRNA genes were performed over chicken sex and bodyweight. Male chickens were related to the enrichment of Bacteroides while female chickens were to the enrichment of Clostridium and Shigella. Male chickens with high body weight were associated with the enrichment of Faecalibacterium and Shuttleworthia. Carbohydrate and lipid metabolisms were suggested as candidate functions for weight gain in the males. This suggests that the variation of cecal bacterial communities and their functions by sex and body weight may be associated with the differences in the growth potentials of broiler chickens.
SEX DIFFERENCES AND REPRODUCTIVE HORMONE INFLUENCES ON HUMAN ODOR PERCEPTION
Doty, Richard L.; Cameron, E. Leslie
2009-01-01
The question of whether men and women differ in their ability to smell has been the topic of scientific investigation for over a hundred years. Although conflicting findings abound, most studies suggest that, for at least some odorants, women outperform men on tests of odor detection, identification, discrimination, and memory. Most functional imaging and electrophysiological studies similarly imply that, when sex differences are present, they favor women. In this review we examine what is known about sex-related alterations in human smell function, including influences of the menstrual cycle, pregnancy, gonadectomy, and hormone replacement therapy on a range of olfactory measures. We conclude that the relationship between reproductive hormones and human olfactory function is complex and that simple associations between circulating levels of gonadal hormones and measures of olfactory function are rarely present. PMID:19272398
Sex differences in stress responses: a critical role for corticotropin-releasing factor.
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.
Discriminant function sexing of fragmentary and complete femora: standards for contemporary Croatia.
Slaus, Mario; Strinović, Davor; Skavić, Josip; Petrovecki, Vedrana
2003-05-01
Determining sex is one of the first and most important steps in identifying decomposed corpses or skeletal remains. Previous studies have demonstrated that populations differ from each other in size and proportion and that these differences can affect metric assessment of sex. This paper establishes standards for determining sex from fragmentary and complete femurs in a modern Croatian population. The sample is composed of 195 femora (104 male and 91 female) from positively identified victims of the 1991 War in Croatia. Six discriminant functions were generated. one using seven variables, three using two variables, and two employing one variable. Results show that complete femora can be sexed with 94.4% accuracy. The same overall accuracy, with slight differences in male/female accuracy, was achieved using a combination of two variables defining the epiphyses, and with the variable maximum diameter of the femoral head.
Sex Differences in the Effects of Unilateral Brain Damage on Intelligence
NASA Astrophysics Data System (ADS)
Inglis, James; Lawson, J. S.
1981-05-01
A sexual dimorphism in the functional asymmetry of the damaged human brain is reflected in a test-specific laterality effect in male but not in female patients. This sex difference explains some contradictions concerning the effects of unilateral brain damage on intelligence in studies in which the influence of sex was overlooked.
Sex-specific evolution during the diversification of live-bearing fishes.
Culumber, Zachary W; Tobler, Michael
2017-08-01
Natural selection is often assumed to drive parallel functional diversification of the sexes. But males and females exhibit fundamental differences in their biology, and it remains largely unknown how sex differences affect macroevolutionary patterns. On microevolutionary scales, we understand how natural and sexual selection interact to give rise to sex-specific evolution during phenotypic diversification and speciation. Here we show that ignoring sex-specific patterns of functional trait evolution misrepresents the macroevolutionary adaptive landscape and evolutionary rates for 112 species of live-bearing fishes (Poeciliidae). Males and females of the same species evolve in different adaptive landscapes. Major axes of female morphology were correlated with environmental variables but not reproductive investment, while male morphological variation was primarily associated with sexual selection. Despite the importance of both natural and sexual selection in shaping sex-specific phenotypic diversification, species diversification was overwhelmingly associated with ecological divergence. Hence, the inter-predictability of mechanisms of phenotypic and species diversification may be limited in many systems. These results underscore the importance of explicitly addressing sex-specific diversification in empirical and theoretical frameworks of evolutionary radiations to elucidate the roles of different sources of selection and constraint.
Smith, Adam S.; Birnie, Andrew K.; Lane, Kent R.; French, Jeffrey A.
2010-01-01
Males and females from many species produce distinct acoustic variations of functionally identical call types. Social behavior may be primed by sex-specific variation in acoustic features of calls. We present a series of acoustic analyses and playback experiments as methods for investigating this subject. Acoustic parameters of phee calls produced by Wied’s black-tufted-ear marmosets (Callithrix kuhlii) were analyzed for sex differences. Discriminant function analyses showed that calls contained sufficient acoustic variation to predict the sex of the caller. Several frequency variables differed significantly between the sexes. Natural and synthesized calls were presented to male–female pairs. Calls elicited differential behavioral responses based on the sex of the caller. Marmosets became significantly more vigilant following the playback of male phee calls (both natural and synthetic) than following female phee calls. In a second playback experiment, synthesized calls were modified by independently manipulating three parameters that were known to differ between the sexes (low-, peak-, and end-frequency). When end-frequency-modified calls were presented, responsiveness was differentiable by sex of caller but did not differ from responses to natural calls. This suggests that marmosets did not use end-frequency to determine the sex of the caller. Manipulation of peak-and low-frequency parameters eliminated the discrete behavioral responses to male and female calls. Together, these parameters may be important features that encode for the sex-specific signal. Recognition of sex by acoustic cues seems to be a multivariate process that depends on the congruency of acoustic features. PMID:19090554
Sex differences in anxiety and emotional behavior
Donner, Nina C.; Lowry, Christopher A.
2013-01-01
Research has elucidated causal links between stress exposure and the development of anxiety disorders, but due to the limited use of female or sex-comparative animal models, little is known about the mechanisms underlying sex differences in those disorders. This is despite an overwhelming wealth of evidence from the clinical literature that the prevalence of anxiety disorders is about twice as high in women compared to men, in addition to gender differences in severity and treatment efficacy. We here review human gender differences in generalized anxiety disorder, panic disorder, posttraumatic stress disorder and anxiety-relevant biological functions, discuss the limitations of classic conflict anxiety tests to measure naturally occurring sex differences in anxiety-like behaviors, describe sex-dependent manifestation of anxiety states after gestational, neonatal, or adolescent stressors, and present animal models of chronic anxiety states induced by acute or chronic stressors during adulthood. Potential mechanisms underlying sex differences in stress-related anxiety states include emerging evidence supporting the existence of two anatomically and functionally distinct serotonergic circuits that are related to the modulation of conflict anxiety and panic-like anxiety, respectively. We discuss how these serotonergic circuits may be controlled by reproductive steroid hormone-dependent modulation of crfr1 and crfr2 expression in the midbrain dorsal raphe nucleus and by estrous stage-dependent alterations of γ-aminobutyric acid (GABAergic) neurotransmission in the periaqueductal gray, ultimately leading to sex differences in emotional behavior. PMID:23588380
Bos, Henny M W; Sandfort, Theo G M; de Bruyn, Eddy H; Hakvoort, Esther M
2008-01-01
The authors examined whether 13- to 15-year-old adolescents who experience feelings of same-sex attraction (SSA) differ from those without such feelings in the quality of relationships with parents, peers, and class mentors and in psychosocial functioning (health status and school performance). The authors also assessed whether differences in psychosocial functioning resulted from differences in the quality of social relationships. Data were collected from 866 Dutch high school students (mean age 13.61 years) by means of a computer-based questionnaire. Of the participants, 74 (8.5%) reported having feelings of SSA. The participants with SSA rated the quality of their relationships with their fathers and their peers lower than did those without SSA. Participants with SSA also had poorer mental health (higher levels of depression and lower levels of self-esteem) and lower school performance. A mediation analysis revealed that differences in psychosocial functioning resulted from differences in the quality of the same-sex attracted youths' social relationships, especially with fathers and peers. Copyright (c) 2008 APA.
Lei, Wei; Li, Mingli; Deng, Wei; Zhou, Yi; Ma, Xiaohong; Wang, Qiang; Guo, Wanjun; Li, Yinfei; Jiang, Lijun; Han, Yuanyuan; Huang, Chaohua; Hu, Xun; Li, Tao
2015-07-16
Male and female patients with schizophrenia show significant differences in a number of important clinical features, yet the neural substrates of these differences are still poorly understood. Here we explored the sex differences in the brain functional aberrations in 124 treatment-naïve patients with first-episode schizophrenia (61 males), compared with 102 age-matched healthy controls (50 males). Maps of degree centrality (DC) and amplitude of low-frequency fluctuations (ALFF) were constructed using resting-state functional magnetic resonance imaging data and compared between groups. We found that: (1) Selective DC reduction was observed in the right putamen (Put_R) in male patients and the left middle frontal gyrus (MFG) in female patients; (2) Functional connectivity analysis (using Put_R and MFG as seeds) found that male and female patients have disturbed functional integration in two separate networks, i.e., the sensorimotor network and the default mode network; (3) Significant ALFF alterations were also observed in these two networks in both genders; (4) Sex specific brain functional alterations were associated with various symptoms in patients. These results suggested that sex-specific patterns of functional aberration existed in schizophrenia, and these patterns were associated with the clinical features both in male and female patients.
Reinhardt, Vanessa P.; Wetherby, Amy M.; Schatschneider, Christopher
2014-01-01
Despite consistent and substantive research documenting a large male to female ratio in Autism Spectrum Disorder (ASD), only a modest body of research exists examining sex differences in characteristics. This study examined sex differences in developmental functioning and early social communication in children with ASD as compared to children with typical development. Sex differences in adaptive behavior and autism symptoms were also examined in children with ASD. Participants (n = 511) were recruited from the Florida State University FIRST WORDS® Project and University of Michigan Autism and Communication Disorders Center. Analyses did not reveal significant effects of sex or a diagnostic group by sex interaction, suggesting a similar phenotype in males and females early in development. Further research is needed to examine sex differences across development. PMID:25189824
Sex-specific phenotypes of hyperthyroidism and hypothyroidism in mice.
Rakov, Helena; Engels, Kathrin; Hönes, Georg Sebastian; Strucksberg, Karl-Heinz; Moeller, Lars Christian; Köhrle, Josef; Zwanziger, Denise; Führer, Dagmar
2016-01-01
Thyroid dysfunction is more common in the female population, however, the impact of sex on disease characteristics has rarely been addressed. Using a murine model, we asked whether sex has an influence on phenotypes, thyroid hormone status, and thyroid hormone tissue response in hyper- and hypothyroidism. Hypo- and hyperthyroidism were induced in 5-month-old female and male wildtype C57BL/6N mice, by LoI/MMI/ClO4 (-) or T4 i.p. treatment over 7 weeks, and control animals underwent sham treatment (N = 8 animals/sex/treatment). Animals were investigated for impact of sex on body weight, food and water intake, body temperature, heart rate, behaviour (locomotor activity, motor coordination, and strength), liver function, serum thyroid hormone status, and cellular TH effects on gene expression in brown adipose tissue, heart, and liver. Male and female mice showed significant differences in behavioural, functional, metabolic, biochemical, and molecular traits of hyper- and hypothyroidism. Hyperthyroidism resulted in increased locomotor activity in female mice but decreased muscle strength and motor coordination preferably in male animals. Hypothyroidism led to increased water intake in male but not female mice and significantly higher serum cholesterol in male mice. Natural sex differences in body temperature, body weight gain, food and water intake were preserved under hyperthyroid conditions. In contrast, natural sex differences in heart rate disappeared with TH excess and deprivation. The variations of hyper- or hypothyroid traits of male and female mice were not explained by classical T3/T4 serum state. TH serum concentrations were significantly increased in female mice under hyperthyroidism, but no sex differences were found under eu- or hypothyroid conditions. Interestingly, analysis of expression of TH target genes and TH transporters revealed little sex dependency in heart, while sex differences in target genes were present in liver and brown adipose tissue in line with altered functional and metabolic traits of hyper- and hypothyroidism. These data demonstrate that the phenotypes of hypo- and hyperthyroidism differ between male and female mice and indicate that sex is an important modifier of phenotypic manifestations.
Sex differences in chronic stress effects on cognition in rodents.
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 hormones in the modulation of irritable bowel syndrome.
Mulak, Agata; Taché, Yvette; Larauche, Muriel
2014-03-14
Compelling evidence indicates sex and gender differences in epidemiology, symptomatology, pathophysiology, and treatment outcome in irritable bowel syndrome (IBS). Based on the female predominance as well as the correlation between IBS symptoms and hormonal status, several models have been proposed to examine the role of sex hormones in gastrointestinal (GI) function including differences in GI symptoms expression in distinct phases of the menstrual cycle, in pre- and post-menopausal women, during pregnancy, hormonal treatment or after oophorectomy. Sex hormones may influence peripheral and central regulatory mechanisms of the brain-gut axis involved in the pathophysiology of IBS contributing to the alterations in visceral sensitivity, motility, intestinal barrier function, and immune activation of intestinal mucosa. Sex differences in stress response of the hypothalamic-pituitary-adrenal axis and autonomic nervous system, neuroimmune interactions triggered by stress, as well as estrogen interactions with serotonin and corticotropin-releasing factor signaling systems are being increasingly recognized. A concept of "microgenderome" related to the potential role of sex hormone modulation of the gut microbiota is also emerging. Significant differences between IBS female and male patients regarding symptomatology and comorbidity with other chronic pain syndromes and psychiatric disorders, together with differences in efficacy of serotonergic medications in IBS patients confirm the necessity for more sex-tailored therapeutic approach in this disorder.
ERIC Educational Resources Information Center
Harris, Lauren Jay
Sex differences in cerebral organization and functioning, and the apparent superiority of males in spatial ability are examined in this paper. Attention is given to several kinds of cognitive and perceptual tasks in which sex differences in spatial ability have been shown to exist; among these are tasks involving: (1) recall and detection of…
Chronic stress and neural function: accounting for sex and age.
Luine, V N; Beck, K D; Bowman, R E; Frankfurt, M; Maclusky, N J
2007-10-01
Cognitive responses to stress follow the temporally dependent pattern originally established by Selye (1) wherein short-term stressors elicit adaptive responses whereas continued stress (chronic) results in maladaptive changes--deleterious effects on physiological systems and impaired cognition. However, this pattern for cognitive effects appears to apply to only half the population (males) and, more specifically, to young, adult males. Females show different cognitive responses to stress. In contrast to impaired cognition in males after chronic stress, female rodents show enhanced performance on the same memory tasks after the same stress. Not only cognition, but anxiety, shows sex-dependent changes following chronic stress--stress is anxiolytic in males and anxiogenic in females. Moreover, behavioral responses to chronic stress are different in developing as well as aging subjects (both sexes) as compared to adults. In aged rats, chronic stress enhances recognition memory in both sexes, does not alter spatial memory, and anxiety effects are opposite to young adults. When pregnant dams are exposed to chronic stress, at adulthood the offspring display yet different consequences of stress on anxiety and cognition, and, in contrast to adulthood when the behavioral effects of stress are reversible, prenatal stress effects appear enduring. Changing levels of estradiol in the sexes over the lifespan appear to contribute to the differences in response to stress. Thus, theories of stress dependent modulations in CNS function--developed solely in male models, focused on peripheral physiological processes and tested in adults--may require revision when applied to a more diverse population (age- and sex-wise) at least in relation to the neural functions of cognition and anxiety. Moreover, these results suggest that other stressors and neural functions should be investigated to determine whether age, sex and gonadal hormones also have an impact.
Onate, James A; Starkel, Cambrie; Clifton, Daniel R; Best, Thomas M; Borchers, James; Chaudhari, Ajit; Comstock, R Dawn; Cortes, Nelson; Grooms, Dustin R; Hertel, Jay; Hewett, Timothy E; Miller, Meghan Maume; Pan, Xueliang; Schussler, Eric; Van Lunen, Bonnie L
2018-01-01
The fourth edition of the Preparticipation Physical Evaluation recommends functional testing for the musculoskeletal portion of the examination; however, normative data across sex and grade level are limited. Establishing normative data can provide clinicians reference points with which to compare their patients, potentially aiding in the development of future injury-risk assessments and injury-mitigation programs. To establish normative functional performance and limb-symmetry data for high school-aged male and female athletes in the United States. Cross-sectional study. Athletic training facilities and gymnasiums across the United States. A total of 3951 male and female athletes who participated on high school-sponsored basketball, football, lacrosse, or soccer teams enrolled in this nationwide study. Functional performance testing consisted of 3 evaluations. Ankle-joint range of motion, balance, and lower extremity muscular power and landing control were assessed via the weight-bearing ankle-dorsiflexion-lunge, single-legged anterior-reach, and anterior single-legged hop-for-distance (SLHOP) tests, respectively. We used 2-way analyses of variance and χ 2 analyses to examine the effects of sex and grade level on ankle-dorsiflexion-lunge, single-legged anterior-reach, and SLHOP test performance and symmetry. The SLHOP performance differed between sexes (males = 187.8% ± 33.1% of limb length, females = 157.5% ± 27.8% of limb length; t = 30.3, P < .001). A Cohen d value of 0.97 indicated a large effect of sex on SLHOP performance. We observed differences for SLHOP and ankle-dorsiflexion-lunge performance among grade levels, but these differences were not clinically meaningful. We demonstrated differences in normative data for lower extremity functional performance during preparticipation physical evaluations across sex and grade levels. The results of this study will allow clinicians to compare sex- and grade-specific functional performances and implement approaches for preventing musculoskeletal injuries in high school-aged athletes.
Galea, L A M; Wainwright, S R; Roes, M M; Duarte-Guterman, P; Chow, C; Hamson, D K
2013-11-01
The hippocampus is an area of the brain that undergoes dramatic plasticity in response to experience and hormone exposure. The hippocampus retains the ability to produce new neurones in most mammalian species and is a structure that is targeted in a number of neurodegenerative and neuropsychiatric diseases, many of which are influenced by both sex and sex hormone exposure. Intriguingly, gonadal and adrenal hormones affect the structure and function of the hippocampus differently in males and females. Adult neurogenesis in the hippocampus is regulated by both gonadal and adrenal hormones in a sex- and experience-dependent way. Sex differences in the effects of steroid hormones to modulate hippocampal plasticity should not be completely unexpected because the physiology of males and females is different, with the most notable difference being that females gestate and nurse the offspring. Furthermore, reproductive experience (i.e. pregnancy and mothering) results in permanent changes to the maternal brain, including the hippocampus. This review outlines the ability of gonadal and stress hormones to modulate multiple aspects of neurogenesis (cell proliferation and cell survival) in both male and female rodents. The function of adult neurogenesis in the hippocampus is linked to spatial memory and depression, and the present review provides early evidence of the functional links between the hormonal modulation of neurogenesis that may contribute to the regulation of cognition and stress. © 2013 British Society for Neuroendocrinology.
Sex Differences and Sex Steroids in Lung Health and Disease
Townsend, Elizabeth A.; Miller, Virginia M.
2012-01-01
Sex differences in the biology of different organ systems and the influence of sex hormones in modulating health and disease are increasingly relevant in clinical and research areas. Although work has focused on sex differences and sex hormones in cardiovascular, musculoskeletal, and neuronal systems, there is now increasing clinical evidence for sex differences in incidence, morbidity, and mortality of lung diseases including allergic diseases (such as asthma), chronic obstructive pulmonary disease, pulmonary fibrosis, lung cancer, as well as pulmonary hypertension. Whether such differences are inherent and/or whether sex steroids play a role in modulating these differences is currently under investigation. The purpose of this review is to define sex differences in lung structure/function under normal and specific disease states, with exploration of whether and how sex hormone signaling mechanisms may explain these clinical observations. Focusing on adult age groups, the review addresses the following: 1) inherent sex differences in lung anatomy and physiology; 2) the importance of certain time points in life such as puberty, pregnancy, menopause, and aging; 3) expression and signaling of sex steroid receptors under normal vs. disease states; 4) potential interplay between different sex steroids; 5) the question of whether sex steroids are beneficial or detrimental to the lung; and 6) the potential use of sex steroid signaling as biomarkers and therapeutic avenues in lung diseases. The importance of focusing on sex differences and sex steroids in the lung lies in the increasing incidence of lung diseases in women and the need to address lung diseases across the life span. PMID:22240244
Wu, Kai; Taki, Yasuyuki; Sato, Kazunori; Hashizume, Hiroshi; Sassa, Yuko; Takeuchi, Hikaru; Thyreau, Benjamin; He, Yong; Evans, Alan C.; Li, Xiaobo; Kawashima, Ryuta; Fukuda, Hiroshi
2013-01-01
Recent studies have demonstrated developmental changes of functional brain networks derived from functional connectivity using graph theoretical analysis, which has been rapidly translated to studies of brain network organization. However, little is known about sex- and IQ-related differences in the topological organization of functional brain networks during development. In this study, resting-state fMRI (rs-fMRI) was used to map the functional brain networks in 51 healthy children. We then investigated the effects of age, sex, and IQ on economic small-world properties and regional nodal properties of the functional brain networks. At a global level of whole networks, we found significant age-related increases in the small-worldness and local efficiency, significant higher values of the global efficiency in boys compared with girls, and no significant IQ-related difference. Age-related increases in the regional nodal properties were found predominately in the frontal brain regions, whereas the parietal, temporal, and occipital brain regions showed age-related decreases. Significant sex-related differences in the regional nodal properties were found in various brain regions, primarily related to the default mode, language, and vision systems. Positive correlations between IQ and the regional nodal properties were found in several brain regions related to the attention system, whereas negative correlations were found in various brain regions primarily involved in the default mode, emotion, and language systems. Together, our findings of the network topology of the functional brain networks in healthy children and its relationship with age, sex, and IQ bring new insights into the understanding of brain maturation and cognitive development during childhood and adolescence. PMID:23390528
Wu, Kai; Taki, Yasuyuki; Sato, Kazunori; Hashizume, Hiroshi; Sassa, Yuko; Takeuchi, Hikaru; Thyreau, Benjamin; He, Yong; Evans, Alan C; Li, Xiaobo; Kawashima, Ryuta; Fukuda, Hiroshi
2013-01-01
Recent studies have demonstrated developmental changes of functional brain networks derived from functional connectivity using graph theoretical analysis, which has been rapidly translated to studies of brain network organization. However, little is known about sex- and IQ-related differences in the topological organization of functional brain networks during development. In this study, resting-state fMRI (rs-fMRI) was used to map the functional brain networks in 51 healthy children. We then investigated the effects of age, sex, and IQ on economic small-world properties and regional nodal properties of the functional brain networks. At a global level of whole networks, we found significant age-related increases in the small-worldness and local efficiency, significant higher values of the global efficiency in boys compared with girls, and no significant IQ-related difference. Age-related increases in the regional nodal properties were found predominately in the frontal brain regions, whereas the parietal, temporal, and occipital brain regions showed age-related decreases. Significant sex-related differences in the regional nodal properties were found in various brain regions, primarily related to the default mode, language, and vision systems. Positive correlations between IQ and the regional nodal properties were found in several brain regions related to the attention system, whereas negative correlations were found in various brain regions primarily involved in the default mode, emotion, and language systems. Together, our findings of the network topology of the functional brain networks in healthy children and its relationship with age, sex, and IQ bring new insights into the understanding of brain maturation and cognitive development during childhood and adolescence.
Sex Education with Young Children.
ERIC Educational Resources Information Center
Koblinsky, Sally; And Others
1980-01-01
Discusses guidelines (developed by the Oregon State University Early Childhood Sex Education Project) for developing teacher-parent cooperation in providing sex education to young children. The guidelines concern how to talk about body differences and body functions; how to deal with masturbation, sex play and obscene language; and how to involve…
Jacobs, Emily G; Weiss, Blair; Makris, Nikos; Whitfield-Gabrieli, Sue; Buka, Stephen L; Klibanski, Anne; Goldstein, Jill M
2017-05-01
Converging preclinical and human evidence indicates that the decline in ovarian estradiol production during the menopausal transition may play a mechanistic role in the neuronal changes that occur early in the aging process. Here, we present findings from a population-based fMRI study characterizing regional and network-level differences in working memory (WM) circuitry in midlife men and women (N = 142; age range 46-53), as a function of sex and reproductive stage. Reproductive histories and hormonal evaluations were used to determine menopausal status. Participants performed a verbal WM task during fMRI scanning. Results revealed robust differences in task-evoked responses in dorsolateral prefrontal cortex and hippocampus as a function of women's reproductive stage, despite minimal variance in chronological age. Sex differences in regional activity and functional connectivity that were pronounced between men and premenopausal women were diminished for postmenopausal women. Critically, analyzing data without regard to sex or reproductive status obscured group differences in the circuit-level neural strategies associated with successful working memory performance. These findings underscore the importance of reproductive age and hormonal status, over and above chronological age, for understanding sex differences in the aging of memory circuitry. Further, these findings suggest that early changes in working memory circuitry are evident decades before the age range typically targeted in cognitive aging studies. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.
Gender Differences in Neurodevelopment and Epigenetics
Chung, Wilson C.J.; Auger, Anthony P.
2013-01-01
Summary The concept that the brain differs in make-up between males and females is not new. For example, it is well-established that anatomists in the nineteenth century found sex differences in human brain weight. The importance of sex differences in the organization of the brain cannot be overstated as they may directly affect cognitive functions, such as verbal skills and visio-spatial tasks in a sex-dependent fashion. Moreover, the incidence of neurological and psychiatric diseases is also highly dependent on sex. These clinical observations reiterate the importance that gender must be taken into account as a relevant possible contributing factor in order to understand the pathogenesis of neurological and psychiatric disorders. Gender-dependent differentiation of the brain has been detected at every levels of organization: morphological, neurochemical, and functional, and have been shown to be primarily controlled by sex differences in gonadal steroid hormone levels during perinatal development. In this review, we discuss how the gonadal steroid hormone testosterone and its metabolites, affect downstream signaling cascades, including gonadal steroid receptor activation, and epigenetic events in order to differentiate the brain in a gender-dependent fashion. PMID:23503727
Explaining sex differences in lifespan in terms of optimal energy allocation in the baboon.
King, Annette M; Kirkwood, Thomas B L; Shanley, Daryl P
2017-10-01
We provide a quantitative test of the hypothesis that sex role specialization may account for sex differences in lifespan in baboons if such specialization causes the dependency of fitness upon longevity, and consequently the optimal resolution to an energetic trade-off between somatic maintenance and other physiological functions, to differ between males and females. We present a model in which females provide all offspring care and males compete for access to reproductive females and in which the partitioning of available energy between the competing fitness-enhancing functions of growth, maintenance, and reproduction is modeled as a dynamic behavioral game, with the optimal decision for each individual depending upon his/her state and the behavior of other members of the population. Our model replicates the sexual dimorphism in body size and sex differences in longevity and reproductive scheduling seen in natural populations of baboons. We show that this outcome is generally robust to perturbations in model parameters, an important finding given that the same behavior is seen across multiple populations and species in the wild. This supports the idea that sex differences in longevity result from differences in the value of somatic maintenance relative to other fitness-enhancing functions in keeping with the disposable soma theory. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.
The sexual dimorphism of obesity
Palmer, Biff F.; Clegg, Deborah J.
2015-01-01
The NIH has recently highlighted the importance of sexual dimorphisms and has mandated inclusion of both sexes in clinical trials and basic research. In this review we highlight new and novel ways sex hormones influence body adiposity and the metabolic syndrome. Understanding how and why metabolic processes differ by sex will enable clinicians to target and personalize therapies based on gender. Adipose tissue function and deposition differ by sex. Females differ with respect to distribution of adipose tissues, males tend to accrue more visceral fat, leading to the classic android body shape which has been highly correlated to increased cardiovascular risk; whereas females accrue more fat in the subcutaneous depot prior to menopause, a feature which affords protection from the negative consequences associated with obesity and the metabolic syndrome. After menopause, fat deposition and accrual shift to favor the visceral depot. This shift is accompanied by a parallel increase in metabolic risk reminiscent to that seen in men. A full understanding of the physiology behind why, and by what mechanisms, adipose tissues accumulate in specific depots and how these depots differ metabolically by sex is important in efforts of prevention of obesity and chronic disease. Estrogens, directly or through activation of their receptors on adipocytes and in adipose tissues, facilitate adipose tissue deposition and function. Evidence suggests that estrogens augment the sympathetic tone differentially to the adipose tissue depots favoring lipid accumulation in the subcutaneous depot in women and visceral fat deposition in men. At the level of adipocyte function, estrogens and their receptors influence the expandability of fat cells enhancing the expandability in the subcutaneous depot and inhibiting it in the visceral depot. Sex hormones clearly influence adipose tissue function and deposition, determining how to capture and utilize their function in a time of caloric surfeit, requires more information. The key will be harnessing the beneficial effects of sex hormones in such a way as to provide ‘healthy’ adiposity. PMID:25578600
Effects of biological sex on the pathophysiology of the heart
Fazal, Loubina; Azibani, Feriel; Vodovar, Nicolas; Cohen Solal, Alain; Delcayre, Claude; Samuel, Jane-Lise
2014-01-01
Cardiovascular diseases are the leading causes of death in men and women in industrialized countries. While the effects of biological sex on cardiovascular pathophysiology have long been known, the sex-specific mechanisms mediating these processes have been further elucidated over recent years. This review aims at analysing the sex-based differences in cardiac structure and function in adult mammals, and the sex-based differences in the main molecular mechanisms involved in the response of the heart to pathological situations. It emerged from this review that the sex-based difference is a variable that should be dealt with, not only in basic science or clinical research, but also with regards to therapeutic approaches. PMID:23763376
Notley, Sean R; Park, Joonhee; Tagami, Kyoko; Ohnishi, Norikazu; Taylor, Nigel A S
2017-05-01
What is the central question of this study? Can sex-related differences in cutaneous vascular and sudomotor responses be explained primarily by variations in the ratio between body surface area and mass during compensable exercise that elicits equivalent heat-loss requirements and mean body temperature changes across participants? What is the main finding and its importance? Mass-specific surface area was a significant determinant of vasomotor and sudomotor responses in men and women, explaining 10-48% of the individual thermoeffector variance. Nonetheless, after accounting for changes in mean body temperature and morphological differences, sex explained only 5% of that inter-individual variability. It was concluded that sex differences in thermoeffector function are morphologically dependent, but not sex dependent. Sex is sometimes thought to be an independent modulator of cutaneous vasomotor and sudomotor function during heat exposure. Nevertheless, it was hypothesized that, when assessed during compensable exercise that evoked equal heat-loss requirements across participants, sex differences in those thermoeffectors would be explained by variations in the ratio between body surface area and mass (specific surface area). To evaluate that possibility, vasomotor and sudomotor functions were assessed in 60 individuals (36 men and 24 women) with widely varying (overlapping) specific surface areas (range, 232.3-292.7 and 241.2-303.1 cm 2 kg -1 , respectively). Subjects completed two trials in compensable conditions (28°C, 36% relative humidity) involving rest (20 min) and steady-state cycling (45 min) at fixed, area-specific metabolic heat-production rates (light, ∼135 W m -2 ; moderate, ∼200 W m -2 ). Equivalent heat-loss requirements and mean body temperature changes were evoked across participants. Forearm blood flow and vascular conductance were positively related to specific surface area during light work in men (r = 0.67 and r = 0.66, respectively; both P < 0.05) and during both exercise intensities in women (light, r = 0.57 and r = 0.69; and moderate, r = 0.64 and r = 0.68; all P < 0.05). Whole-body and local sweat rates were negatively related to that ratio (correlation coefficient range, -0.33 to -0.62; all P < 0.05) during both work rates in men and women. Those relationships accounted for 10-48% of inter-individual thermoeffector variance (P < 0.05). Furthermore, after accounting for morphological differences, sex explained no more than 5% of that variability (P < 0.05). It was concluded that, when assessed during compensable exercise, sex differences in thermoeffector function were largely determined morphologically, rather than being sex dependent. © 2017 The Authors. Experimental Physiology © 2017 The Physiological Society.
Roumia, Mazen; Aronow, Herbert D; Soukas, Peter; Gosch, Kensey; Smolderen, Kim G; Spertus, John A; Abbott, J Dawn
2017-04-01
Peripheral artery disease (PAD) is associated with poor health status (symptoms, functioning, quality of life (QOL)). Whether sex differences exist in PAD-specific health status is unknown. In patients presenting to a specialty clinic with new-onset or recent exacerbation of PAD, we examined sex differences as assessed by the Peripheral Artery Questionnaire (PAQ). The Patient-centered Outcomes Related to TReatment Practices in Peripheral Arterial Disease: Investigating Trajectories (PORTRAIT) study is a multicenter, international prospective study of patients with new or worsening PAD symptoms. Baseline characteristics and mean PAQ scores were compared among women ( n=481) and men ( n=793) before they underwent treatment. The independent association of sex with health status was assessed with multivariable linear regression. As compared with men, women were less often Caucasian, married and employed, and more often lacking health insurance, living alone (36.2% vs 23.6%, p<0.001), had depression and avoided care due to cost (17.0% vs 12.3%, p=0.018). Women and men were of a similar age and education level, and had similar ankle-brachial index (ABI) values (0.7 ± 0.2 in both groups, p=0.052). Female sex was independently associated with lower PAQ scores on all domains (physical functioning adjusted mean difference of -8.40, p<0.001; social functioning adjusted mean difference of -6.8, p<0.001; QOL adjusted mean difference of -6.7, p<0.001), although no differences were observed in treatment satisfaction (adjusted mean difference -0.20, p=0.904). Despite similar ABIs, women presenting with symptoms of PAD had poorer PAD-specific functioning as compared with men, impacting all major health status domains, independent of socio-economic and clinical characteristics.
Crane, Natania A; Schuster, Randi Melissa; Mermelstein, Robin J; Gonzalez, Raul
2015-01-01
Earlier initiation of cannabis use is associated with poorer neuropsychological functioning across several domains. Given well-documented sex differences in neuromaturation during adolescence, initiation of cannabis use during this time may affect neuropsychological functioning differently for males and females. In the current study, we examined sex differences in the relationship between age of initiated cannabis use and neuropsychological performance after controlling for amount of lifetime cannabis use in 44 male and 25 female young adult cannabis users. We found that an earlier age of initiated use was related to poorer episodic memory, especially immediate recall, in females, but not in males. On the other hand, we found that, surprisingly, an earlier age of initiated use was associated with better decision making overall. However, exploratory analyses found sex-specific factors associated with decision making and age of initiated use, specifically that attention-deficit/hyperactivity disorder (ADHD) symptoms in females may drive the relationship between an earlier age of initiated use and better decision making. Further, an earlier age of initiated use was associated with less education, a lower IQ, and fewer years of mother's education for females, but more lifetime cannabis use for males. Taken together, our findings suggest there are sex differences in the associations between age of initiated cannabis use and neuropsychological functioning. The current study provides preliminary evidence that males and females may have different neuropsychological vulnerabilities that place them at risk for initiating cannabis use and continued cannabis use, highlighting the importance of examining the impact of cannabis on neuropsychological functioning separately for males and females.
Social Status Affects the Degree of Sex Difference in the Songbird Brain
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
The origin and evolution of vertebrate sex chromosomes and dosage compensation
Livernois, A M; Graves, J A M; Waters, P D
2012-01-01
In mammals, birds, snakes and many lizards and fish, sex is determined genetically (either male XY heterogamy or female ZW heterogamy), whereas in alligators, and in many reptiles and turtles, the temperature at which eggs are incubated determines sex. Evidently, different sex-determining systems (and sex chromosome pairs) have evolved independently in different vertebrate lineages. Homology shared by Xs and Ys (and Zs and Ws) within species demonstrates that differentiated sex chromosomes were once homologous, and that the sex-specific non-recombining Y (or W) was progressively degraded. Consequently, genes are left in single copy in the heterogametic sex, which results in an imbalance of the dosage of genes on the sex chromosomes between the sexes, and also relative to the autosomes. Dosage compensation has evolved in diverse species to compensate for these dose differences, with the stringency of compensation apparently differing greatly between lineages, perhaps reflecting the concentration of genes on the original autosome pair that required dosage compensation. We discuss the organization and evolution of amniote sex chromosomes, and hypothesize that dosage insensitivity might predispose an autosome to evolving function as a sex chromosome. PMID:22086077
Foucher, Kharma C
2017-10-01
Hip osteoarthritis results in abnormal gait mechanics, but it is not known whether abnormalities are the same in men and women. The hypothesis tested was that gait abnormalities are different in men and women with hip osteoarthritis vs. sex-specific asymptomatic groups. 150 subjects with mild through severe radiographic hip osteoarthritis and 159 asymptomatic subjects were identified from an Institutional Review Board-approved motion analysis data repository. Sagittal plane hip range of motion and peak external moments about the hip, in all three planes, averaged from normal speed walking trials, were compared for men and women, with and without hip osteoarthritis using analysis of variance. There were significant sex by group interactions for the external peak hip adduction and external rotation moments (P=0.009-0.045). Although asymptomatic women had peak adduction and external rotation moments that were respectively 12% higher and 23% lower than asymptomatic men (P=0.026-0.037), these variables did not differ between men and women with hip osteoarthritis (P≥0.684). The osteoarthritis vs. asymptomatic group difference in the peak hip adduction moment was 45% larger in women than in men. The osteoarthritis vs. asymptomatic group difference in the peak hip external rotation moment was 55% larger for men than for women (P<0.001). Sex did not influence the association between radiographic severity and gait variables. Normal sex differences in gait were not seen in hip osteoarthritis. Sex-specific adaptations may reflect different aspects of hip abductor function. Men and women with hip osteoarthritis may require different interventions to improve function. Copyright © 2017 Elsevier Ltd. All rights reserved.
Establishing a link between sex-related differences in the structural connectome and behaviour.
Tunç, Birkan; Solmaz, Berkan; Parker, Drew; Satterthwaite, Theodore D; Elliott, Mark A; Calkins, Monica E; Ruparel, Kosha; Gur, Raquel E; Gur, Ruben C; Verma, Ragini
2016-02-19
Recent years have witnessed an increased attention to studies of sex differences, partly because such differences offer important considerations for personalized medicine. While the presence of sex differences in human behaviour is well documented, our knowledge of their anatomical foundations in the brain is still relatively limited. As a natural gateway to fathom the human mind and behaviour, studies concentrating on the human brain network constitute an important segment of the research effort to investigate sex differences. Using a large sample of healthy young individuals, each assessed with diffusion MRI and a computerized neurocognitive battery, we conducted a comprehensive set of experiments examining sex-related differences in the meso-scale structures of the human connectome and elucidated how these differences may relate to sex differences at the level of behaviour. Our results suggest that behavioural sex differences, which indicate complementarity of males and females, are accompanied by related differences in brain structure across development. When using subnetworks that are defined over functional and behavioural domains, we observed increased structural connectivity related to the motor, sensory and executive function subnetworks in males. In females, subnetworks associated with social motivation, attention and memory tasks had higher connectivity. Males showed higher modularity compared to females, with females having higher inter-modular connectivity. Applying multivariate analysis, we showed an increasing separation between males and females in the course of development, not only in behavioural patterns but also in brain structure. We also showed that these behavioural and structural patterns correlate with each other, establishing a reliable link between brain and behaviour. © 2016 The Author(s).
Gaignard, Pauline; Savouroux, Stéphane; Liere, Philippe; Pianos, Antoine; Thérond, Patrice; Schumacher, Michael; Slama, Abdelhamid; Guennoun, Rachida
2015-08-01
Sex steroids regulate brain function in both normal and pathological states. Mitochondria are an essential target of steroids, as demonstrated by the experimental administration of 17β-estradiol or progesterone (PROG) to ovariectomized female rodents, but the influence of endogenous sex steroids remains understudied. To address this issue, mitochondrial oxidative stress, the oxidative phosphorylation system, and brain steroid levels were analyzed under 3 different experimental sets of endocrine conditions. The first set was designed to study steroid-mediated sex differences in young male and female mice, intact and after gonadectomy. The second set concerned young female mice at 3 time points of the estrous cycle in order to analyze the influence of transient variations in steroid levels. The third set involved the evaluation of the effects of a permanent decrease in gonadal steroids in aged male and female mice. Our results show that young adult females have lower oxidative stress and a higher reduced nicotinamide adenine dinucleotide (NADH)-linked respiration rate, which is related to a higher pyruvate dehydrogenase complex activity as compared with young adult males. This sex difference did not depend on phases of the estrous cycle, was suppressed by ovariectomy but not by orchidectomy, and no longer existed in aged mice. Concomitant analysis of brain steroids showed that pregnenolone and PROG brain levels were higher in females during the reproductive period than in males and decreased with aging in females. These findings suggest that the major male/female differences in brain pregnenolone and PROG levels may contribute to the sex differences observed in brain mitochondrial function.
ERIC Educational Resources Information Center
Lenney, Ellen
1981-01-01
Reports experimental research testing the following hypotheses: (1) sex differences in self-confidence are a function of a particular ability area; and (2) self-confidence of women is more influenced than men's by the characteristics of the particular individual with whom they compare themselves. (Author/EF)
WHY WE SHOULD CONSIDER SEX (AND STUDY SEX DIFFERENCES) IN ADDICTION RESEARCH
Sanchis-Segura, Carla; Becker, Jill
2017-01-01
Among mammals, every cell has a biological sex, and the sex of an individual pervades its body and brain. In this review we describe the processes through which mammals become phenotypically male or female by organizational and activational influences of genes and hormones throughout development. We emphasized that the molecular and cellular changes triggered by sex chromosomes and steroid hormones may generate sex differences in overt physiological functions and behavior, but they may alternatively promote end-point convergences between males and females. Clinical and preclinical evidence suggest that sex and gender differences modulate drug consumption as well as of the transition towards drug-promoted pathological states such as dependence and addiction. Additionally, sex differences in drug pharmacokinetics and pharmacodynamics will also influence dependence and addiction as well as side effects of drugs. These effects will further interact with socially gendered factors to result in sex differences in the access to, engagement in, and efficacy of any therapeutic attempt. Finally, we maintain that “sex-sameness” is as important as “sex differences” when building a complete understanding of biology for both males and females and provide a framework with which to classify and guide investigation into the mechanisms mediating sex differences and sex-sameness. PMID:27029841
Liu, Mingyue; Oyarzabal, Esteban; Yang, Rui; Murphy, Stephanie J; Hurn, Patricia D.
2008-01-01
Female astrocytes sustain less cell death from oxygen-glucose deprivation (OGD) than male astrocytes. Arimidex, an aromatase inhibitor, abolishes these sex differences. To verify sex-dependent differences in P450 aromatase function in astrocyte cell death following OGD, we developed a novel method that uses sex-specific and genotype-specific single pup primary astrocyte cultures from wild-type (WT) and aromatase-knockout (ArKO) mice. After determining sex by external and internal examination as well as PCR and genotype by PCR amplification of tail cDNA, we established cultures from 1−3 day-old male and female, WT and ArKO mice pups and grew them to confluence in estrogen-free media. Cell death was measured by lactate dehydrogenase (LDH) assay. Our study shows that, while WT female astrocytes are more resistant to OGD than WT male cells, sex differences disappear in ArKO cells. Cell death is significantly increased in ArKO compared to WT in female astrocytes but not male cells. Therefore, P450 aromatase appears to be essential in endogenous neuroprotection in females, and this finding may have clinical implications. This innovative technique may also be applied to other in vitro studies of sex-related functional differences. PMID:18436308
Investigating the Influence of Biological Sex on the Behavioral and Neural Basis of Face Recognition
2017-01-01
Abstract There is interest in understanding the influence of biological factors, like sex, on the organization of brain function. We investigated the influence of biological sex on the behavioral and neural basis of face recognition in healthy, young adults. In behavior, there were no sex differences on the male Cambridge Face Memory Test (CFMT)+ or the female CFMT+ (that we created) and no own-gender bias (OGB) in either group. We evaluated the functional topography of ventral stream organization by measuring the magnitude and functional neural size of 16 individually defined face-, two object-, and two place-related regions bilaterally. There were no sex differences in any of these measures of neural function in any of the regions of interest (ROIs) or in group level comparisons. These findings reveal that men and women have similar category-selective topographic organization in the ventral visual pathway. Next, in a separate task, we measured activation within the 16 face-processing ROIs specifically during recognition of target male and female faces. There were no sex differences in the magnitude of the neural responses in any face-processing region. Furthermore, there was no OGB in the neural responses of either the male or female participants. Our findings suggest that face recognition behavior, including the OGB, is not inherently sexually dimorphic. Face recognition is an essential skill for navigating human social interactions, which is reflected equally in the behavior and neural architecture of men and women. PMID:28497111
Scherf, K Suzanne; Elbich, Daniel B; Motta-Mena, Natalie V
2017-01-01
There is interest in understanding the influence of biological factors, like sex, on the organization of brain function. We investigated the influence of biological sex on the behavioral and neural basis of face recognition in healthy, young adults. In behavior, there were no sex differences on the male Cambridge Face Memory Test (CFMT)+ or the female CFMT+ (that we created) and no own-gender bias (OGB) in either group. We evaluated the functional topography of ventral stream organization by measuring the magnitude and functional neural size of 16 individually defined face-, two object-, and two place-related regions bilaterally. There were no sex differences in any of these measures of neural function in any of the regions of interest (ROIs) or in group level comparisons. These findings reveal that men and women have similar category-selective topographic organization in the ventral visual pathway. Next, in a separate task, we measured activation within the 16 face-processing ROIs specifically during recognition of target male and female faces. There were no sex differences in the magnitude of the neural responses in any face-processing region. Furthermore, there was no OGB in the neural responses of either the male or female participants. Our findings suggest that face recognition behavior, including the OGB, is not inherently sexually dimorphic. Face recognition is an essential skill for navigating human social interactions, which is reflected equally in the behavior and neural architecture of men and women.
Sex Differences in Insular Cortex Gyri Responses to the Valsalva Maneuver.
Macey, Paul M; Rieken, Nicholas S; Kumar, Rajesh; Ogren, Jennifer A; Middlekauff, Holly R; Wu, Paula; Woo, Mary A; Harper, Ronald M
2016-01-01
Sex differences in autonomic regulation may underlie cardiovascular disease variations between females and males. One key autonomic brain region is the insular cortex, which typically consists of five main gyri in each hemisphere, and shows a topographical organization of autonomic function across those gyri. The present study aims to identify possible sex differences in organization of autonomic function in the insula. We studied brain functional magnetic resonance imaging (fMRI) responses to a series of four 18-s Valsalva maneuvers in 22 healthy females (age ± SD: 50.0 ± 7.9 years) and 36 healthy males (45.3 ± 9.2 years). Comparisons of heart rate (HR) and fMRI signals were performed with repeated measures ANOVA (threshold P < 0.05 for all findings). All subjects achieved the target 30 mmHg expiratory pressure for all challenges. Typical HR responses were elicited by the maneuver, including HR increases from ~4 s into the strain period (Phase II) and rapid declines to below baseline 5-10 s, following strain release (Phase IV). Small, but significant, sex differences in HR percent change occurred during the sympathetic-dominant Phase II (female < male) and parasympathetic-dominant Phase IV (female > male, i.e., greater undershoot in males). The insular cortices showed similar patterns in all gyri, with greater signal decreases in males than females. Both sexes exhibited an anterior-posterior topographical organization of insular responses during Phase II, with anterior gyri showing higher responses than more posterior gyri. The exception was the right anterior-most gyrus in females, which had lower responses than the four other right gyri. Responses were lateralized, with right-sided dominance during Phase II in both sexes, except the right anterior-most gyrus in females, which showed lower responses than the left. The findings confirm the anterior and right-sided sympathetic dominance of the insula. Although sex differences were prominent in response magnitude, organization differences between males and females were limited to the right anterior-most gyrus, which showed a lower fMRI response in females vs. males (and vs. other gyri in females). The sex differences suggest a possible differing baseline state of brain physiology or tonic functional activity between females and males, especially in the right anterior-most gyrus.
SEX DIFFERENCES DURING HUMOR APPRECIATION IN CHILD SIBLING-PAIRS
Vrticka, Pascal; Neely, Michelle; Walter, Elizabeth; Black, Jessica M.; Reiss, Allan L.
2013-01-01
The developmental origin of sex differences in adult brain function is poorly understood. Elucidating neural mechanisms underlying comparable cognitive functionality in both children and adults is required to address this gap. Humor appreciation represents a particularly relevant target for such developmental research because explanatory theories apply across the life span and underlying neurocircuitry shows sex differences in adults. As a positive mood state, humor is also of interest due to sex differences in rates of depression, a disorder afflicting twice as many women as men. In this study, we employed fMRI to investigate brain responses to funny versus positive (and neutral) video clips in 22 children ages 6 to 13 years, including 8 sibling pairs. Our data revealed increased activity to funny clips in bilateral temporo-occipital cortex, midbrain, and amygdala in girls. Conversely, we found heightened activation to positive clips in bilateral inferior parietal lobule, fusiform gyrus, inferior frontal gyrus, amygdala, and ventromedial prefrontal cortex in boys. Many of these effects persisted when looking at sibling-pairs only. We interpret such findings as reflecting the presence of early sex divergence in reward saliency / expectation and stimulus relevance attribution. These findings are discussed in the context of evolutionary and developmental theories of humor function. PMID:23672302
Khalifa, Abdel Rahman M; Abdel-Rahman, Engy A; Mahmoud, Ali M; Ali, Mohamed H; Noureldin, Maha; Saber, Saber H; Mohsen, Mahmoud; Ali, Sameh S
2017-03-01
Sex-specific differences in mitochondrial function and free radical homeostasis are reported in the context of aging but not well-established in pathogeneses occurring early in life. Here, we examine if sex disparity in mitochondria function, morphology, and redox status starts early and hence can be implicated in sexual dimorphism in cardiac as well as neurological disorders prevalent at young age. Although mitochondrial activity in the heart did not significantly vary between sexes, female brain exhibited enhanced respiration and higher reserve capacity. This was associated with lower H 2 O 2 production in female cardiac and brain tissues. Using transmission electron microscopy, we found that the number of female cardiac mitochondria is moderately greater (117 ± 3%, P = 0.049, N = 4) than male's, which increased significantly for cortical mitochondria (134 ± 4%, P = 0.001, N = 4). However, male's cardiac mitochondria exhibited fragmented, circular, and smaller mitochondria relative to female's mitochondria, while no morphologic sex-dependent differences were observed in cortical mitochondria. No sex differences were detected in Nox2 and Nox4 proteins or O 2 -consuming/H 2 O 2 -producing activities in brain homogenate or synaptosomes. However, a strong trend of increased EPR-detected NOX superoxide in male synaptosomes hinted at higher superoxide dismutase activity in female brains, which was confirmed by two independent protocols. We also provide direct evidence that respiring mitochondria generally produce an order-of-magnitude lower reactive oxygen species (ROS) proportions than currently estimated. Our results indicate that sex differences in mitochondrial biogenesis, bioenergetics, and morphology may start at young age and that sex-dependent SOD capacity may be responsible for differences in ROS homeostasis in heart and brain. © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.
Sex-driven vulnerability in stress and drug abuse.
Berry, Alessandra; Raggi, Carla; Borgi, Marta; Cirulli, Francesca
2016-01-01
A growing body of literature shows that a link exists between substance abuse and stress and that the crosstalk of sex hormones with the neuroendocrine system might differently prime vulnerability to drug addiction in male and female subjects. Thus, understanding the neurobiological mechanisms of addiction and the identification of sex-driven determinants in vulnerability to drug abuse may help to better devise and/or implement strategic (pharmacological, behavioural, social) interventions to prevent or face the issue of addiction. Differences between sexes can be found at all stages of life (in both the animal model and human studies) and may account for genetic, epigenetic and environmental/hormonal factors that in turn affect the functionality of the whole organism leading also to a sex-driven differential vulnerability or resilience to non-communicable pathologies. These include the onset and precipitation of stress-related psychiatric disorders as well as "substance-related and addictive disorders" (as defined in the DSM-V). This paper reviews the scientific literature highlighting significant differences in male and female subjects in stress and neuroendocrine function and the implications for sex-dependent differential vulnerability to drug addiction.
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.
Sex Differences in Autonomic Correlates of Conduct Problems and Aggression
BEAUCHAINE, THEODORE P.; HONG, JAMES; MARSH, PENNY
2009-01-01
Objective To examine sex differences in autonomic nervous system functioning in children and adolescents with conduct problems and to evaluate the role of aggression in predicting autonomic nervous system functioning, over and above the effects of disruptive behavior. Although deficiencies in autonomic responding among boys with oppositional defiant disorder and/or conduct disorder are well documented, it remains unclear whether such findings extend to girls or apply only to children with aggressive forms of conduct problems. Method Electrodermal responding, cardiac pre-ejection period, and respiratory sinus arrhythmia were recorded while boys (n = 110; 53 with conduct problems, 57 controls) and girls (n = 65; 33 with conduct problems, 32 controls) between the ages of 8 and 12 sat for an extended baseline, then played a game with conditions of reward and frustrative nonreward. Results Both sex effects and aggression effects were found. Aggressive boys with conduct problems demonstrated reduced autonomic functioning, consistent with previous research. In contrast, aggressive girls with conduct problems exhibited greater electrodermal responding than controls, with no differences in cardiovascular reactivity to incentives. Conclusions Observed sex differences in the autonomic correlates of conduct problems and aggression may suggest different etiological mechanisms of externalizing psychopathology for girls compared with boys. PMID:18520959
Burke, Sarah M.; Cohen-Kettenis, Peggy T.; Veltman, Dick J.; Klink, Daniel T.; Bakker, Julie
2014-01-01
The odorous steroid androstadienone, a putative male chemo-signal, was previously reported to evoke sex differences in hypothalamic activation in adult heterosexual men and women. In order to investigate whether puberty modulated this sex difference in response to androstadienone, we measured the hypothalamic responsiveness to this chemo-signal in 39 pre-pubertal and 41 adolescent boys and girls by means of functional magnetic resonance imaging. We then investigated whether 36 pre-pubertal children and 38 adolescents diagnosed with gender dysphoria (GD; DSM-5) exhibited sex-atypical (in accordance with their experienced gender), rather than sex-typical (in accordance with their natal sex) hypothalamic activations during olfactory stimulation with androstadienone. We found that the sex difference in responsiveness to androstadienone was already present in pre-pubertal control children and thus likely developed during early perinatal development instead of during sexual maturation. Adolescent girls and boys with GD both responded remarkably like their experienced gender, thus sex-atypical. In contrast, pre-pubertal girls with GD showed neither a typically male nor female hypothalamic activation pattern and pre-pubertal boys with GD had hypothalamic activations in response to androstadienone that were similar to control boys, thus sex-typical. We present here a unique data set of boys and girls diagnosed with GD at two different developmental stages, showing that these children possess certain sex-atypical functional brain characteristics and may have undergone atypical sexual differentiation of the brain. PMID:24904525
Sex-based differences in brain alterations across chronic pain conditions
Gupta, Arpana; Mayer, Emeran A; Fling, Connor; Labus, Jennifer S; Naliboff, Bruce D; Hong, Jui-Yang; Kilpatrick, Lisa A
2016-01-01
Common brain mechanisms are thought to play a significant role across a multitude of chronic pain syndromes. In addition, there is strong evidence for the existence of sex differences in the prevalence of chronic pain and in the neurobiology of pain. Thus, it is important to consider sex when developing general principals of pain neurobiology. The goal of the current review is to evaluate what is known about sex-specific brain alterations across multiple chronic pain populations. A total of 15 sex difference and 143 single-sex manuscripts were identified out of 412 chronic pain neuroimaging manuscripts. Results from sex difference studies indicate more prominent primary sensorimotor structural and functional alterations in female chronic pain patients compared to male chronic pain patients; differences in the nature and degree of insula alterations, with greater insula reactivity in male patients; differences in the degree of anterior cingulate structural alterations; and differences in emotional-arousal reactivity. Qualitative comparisons of male-specific and female-specific studies appear to be consistent with the results from sex difference studies. Given these differences, mixed-sex studies of chronic pain risk creating biased data or missing important information and single-sex studies have limited generalizability. The advent of large scale neuroimaging databases will likely aid in building a more comprehensive understanding of sex differences and commonalities in brain mechanisms underlying chronic pain. PMID:27870423
Sex-based differences in brain alterations across chronic pain conditions.
Gupta, Arpana; Mayer, Emeran A; Fling, Connor; Labus, Jennifer S; Naliboff, Bruce D; Hong, Jui-Yang; Kilpatrick, Lisa A
2017-01-02
Common brain mechanisms are thought to play a significant role across a multitude of chronic pain syndromes. In addition, there is strong evidence for the existence of sex differences in the prevalence of chronic pain and in the neurobiology of pain. Thus, it is important to consider sex when developing general principals of pain neurobiology. The goal of the current Mini-Review is to evaluate what is known about sex-specific brain alterations across multiple chronic pain populations. A total of 15 sex difference and 143 single-sex articles were identified from among 412 chronic pain neuroimaging articles. Results from sex difference studies indicate more prominent primary sensorimotor structural and functional alterations in female chronic pain patients compared with male chronic pain patients: differences in the nature and degree of insula alterations, with greater insula reactivity in male patients; differences in the degree of anterior cingulate structural alterations; and differences in emotional-arousal reactivity. Qualitative comparisons of male-specific and female-specific studies appear to be consistent with the results from sex difference studies. Given these differences, mixed-sex studies of chronic pain risk creating biased data or missing important information and single-sex studies have limited generalizability. The advent of large-scale neuroimaging databases will likely aid in building a more comprehensive understanding of sex differences and commonalities in brain mechanisms underlying chronic pain. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Cyders, Melissa A
2013-02-01
Before it is possible to test whether men and women differ in impulsivity, it is necessary to evaluate whether impulsivity measures are invariant across sex. The UPPS-P Impulsive Behavior Scale (negative urgency, lack of premeditation, lack of perseverance, and sensation seeking, with added subscale of positive urgency) is one measure of five dispositions toward rash action that has shown to have robust and clinically useful relationships among risk-taking outcomes. In the current research, the author examined (a) the psychometric measurement invariance of the UPPS-P across sex, (b) the scale's structural invariance across sex, and (c) whether the five impulsivity traits differentially relate to risk outcomes as a function of sex. In a sample of 1,372 undergraduates, the author found evidence for measurement and invariance across sex: Thus, comparisons of men and women on the UPPS-P can be considered valid. Additionally, although males tend to report higher levels of sensation seeking and positive urgency (and possibly lack of perseverance), the relationships between the UPPS-P traits and risk outcomes were generally invariant across sex. The UPPS-P appears to function comparably across males and females, and mean differences on this scale between the sexes can be thought to reflect trait-level differences.
Sex Differences Influencing Micro- and Macrovascular Endothelial Phenotype In Vitro.
Huxley, Virginia H; Kemp, Scott S; Schramm, Christine; Sieveking, Steve; Bingaman, Susan; Yu, Yang; Zaniletti, Isabella; Stockard, Kevin; Wang, Jianjie
2018-06-09
Endothelial dysfunction is an early hallmark of multiple disease states that also display sex differences with respect to age of onset, frequency, and severity. Results of in vivo studies of basal and stimulated microvascular barrier function revealed sex differences difficult to ascribe to specific cells or environmental factors. The present study evaluated endothelial cells (EC) isolated from macro- and/or microvessels of reproductively mature rats under the controlled conditions of low-passage culture to test the assumption that EC phenotype would be sex-independent. The primary finding was that EC, regardless of where they are derived, retain a sex-bias in low-passage culture, independent of varying levels of reproductive hormones. Implications of the work include the fallacy of expecting a universal set of mechanisms derived from study of EC from one sex and/or one vascular origin to apply uniformly to all EC under unstimulated conditions no less in the disease state. Vascular endothelial cells (EC) are heterogeneous with respect to phenotype reflecting at least organ of origin, location within the vascular network, and physical forces. Sex, as an independent influence on EC functions in health or etiology, susceptibility, and progression of dysfunction in numerous disease states, has been largely ignored. The current study focussed on EC isolated from aorta (macrovascular) and skeletal muscle vessels (microvascular) of age-matched male and female rats under identical conditions of short term (passage 4) culture. We tested the hypothesis that genomic sex would not influence endothelial growth, wound healing, morphology, lactate production, or messenger RNA and protein expression of key proteins (sex hormone receptors for androgen (AR) and oestrogen (ERα and ERβ); PECAM-1 and VE-CAD mediating barrier function; α v β 3 and N-Cadherin influencing matrix interactions; ICAM-1 and VCAM-1 mediating EC/white cell adhesion). The hypothesis was rejected as EC origin (macro- versus microvessel) and sex influenced multiple phenotypic characteristics. Statistical model analysis of EC growth demonstrated an hierarchy of variable importance, recapitulated for other phenotypic characteristics, wherein predictions assuming EC homogeneity < Sex < Vessel Origin < Sex and Vessel Origin. Further, patterns of EC mRNA expression by vessel origin and by sex did not predict protein expression. Overall the study demonstrated that accurate assessment of sex-linked EC dysfunction first requires understanding of EC function by position in the vascular tree and by sex. Results from a single EC tissue source/species/sex cannot provide universal insight into the mechanisms regulating in vivo endothelial function in health, no less disease. (250) This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
Fox, Helen C.; Sinha, Rajita
2009-01-01
Extensive research indicates that chronic substance abuse disrupts stress and reward systems of the brain. Gender variation within these stress-system alterations, including the impact of sex hormones on these changes, may influence sex-specific differences in both the development of, and recovery from, dependency. As such, gender variations in stress-system function may also provide a viable explanation for why women are markedly more vulnerable than men to the negative consequences of drug use. This article therefore initially reviews studies that have examined gender differences in emotional and biophysiological changes to the stress and reward system following the acute administration of drugs, including cocaine, alcohol, and nicotine. The article then reviews studies that have examined gender differences in response to various types of stress in both healthy and drug-abusing populations. Studies examining the impact of sex hormones on these gender-related responses are also reported. The implications of these sex-specific variations in stress and reward system function are discussed in terms of both comorbid psychopathology and treatment outcome. PMID:19373619
Effects of biological sex on the pathophysiology of the heart.
Fazal, Loubina; Azibani, Feriel; Vodovar, Nicolas; Cohen Solal, Alain; Delcayre, Claude; Samuel, Jane-Lise
2014-02-01
Cardiovascular diseases are the leading causes of death in men and women in industrialized countries. While the effects of biological sex on cardiovascular pathophysiology have long been known, the sex-specific mechanisms mediating these processes have been further elucidated over recent years. This review aims at analysing the sex-based differences in cardiac structure and function in adult mammals, and the sex-based differences in the main molecular mechanisms involved in the response of the heart to pathological situations. It emerged from this review that the sex-based difference is a variable that should be dealt with, not only in basic science or clinical research, but also with regards to therapeutic approaches. © 2013 The British Pharmacological Society.
The biological effects of sex hormones on rabbit articular chondrocytes from different genders.
Chang, Shwu Jen; Kuo, Shyh Ming; Lin, Yen Ting; Yang, Shan-Wei
2014-01-01
The aim of this study was to investigate the biological effects of sex hormones (17β-estradiol and testosterone) on rabbit articular chondrocytes from different genders. We cultured primary rabbit articular chondrocytes from both genders with varying concentration of sex hormones. We evaluate cell proliferation and biochemical functions by MTT and GAG assay. The chondrocyte function and phenotypes were analyzed by mRNA level using RT-PCR. Immunocytochemical staining was also used to evaluate the generation of collagen-II. This study demonstrated that 17β-estradiol had greater positive regulation on the biological function and gene expressions of articular chondrocytes than testosterone, with the optimal concentrations of 10(-6) and 10(-7) M, particularly for female chondrocytes.
Ittig, S; Studerus, E; Papmeyer, M; Uttinger, M; Koranyi, S; Ramyead, A; Riecher-Rössler, A
2015-02-01
Several sex differences in schizophrenia have been reported including differences in cognitive functioning. Studies with schizophrenia patients and healthy controls (HC) indicate that the sex advantage for women in verbal domains is also present in schizophrenia patients. However, findings have been inconsistent. No study focused on sex-related cognitive performance differences in at-risk mental state for psychosis (ARMS) individuals yet. Thus, the aim of the present study was to investigate sex differences in cognitive functioning in ARMS, first episode psychosis (FEP) and HC subjects. We expected a better verbal learning and memory performance of women in all groups. The neuropsychological data analysed in this study were collected within the prospective Früherkennung von Psychosen (FePsy) study. In total, 118 ARMS, 88 FEP individuals and 86 HC completed a cognitive test battery covering the domains of executive functions, attention, working memory, verbal learning and memory, IQ and speed of processing. Women performed better in verbal learning and memory regardless of diagnostic group. By contrast, men as compared to women showed a shorter reaction time during the working memory task across all groups. The results provide evidence that women generally perform better in verbal learning and memory, independent of diagnostic group (ARMS, FEP, HC). The finding of a shorter reaction time for men in the working memory task could indicate that men have a superior working memory performance since they responded faster during the target trials, while maintaining a comparable overall working memory performance level. Copyright © 2014 Elsevier Masson SAS. All rights reserved.
Sex assessment using clavicle measurements: inter- and intra-population comparisons.
Králík, Miroslav; Urbanová, Petra; Wagenknechtová, Martina
2014-01-01
We studied sexual dimorphism of the human clavicle in order to describe size variation and create population-specific discriminant tools for morphometric sex assessment. The studied sample consisted of 200 skeletons of adult individuals obtained from the University of Athens Human Skeletal Reference Collection, Athens, Greece. The specimens were well-documented and represented a modern population from cemeteries in the Athens area. Six dimensions typically used for clavicle measurements were recorded. For sexing clavicles, we used both traditional univariate (limiting, demarking and sectioning points) and multivariate discriminant function analysis. The accuracy of the best five classification equations/functions ranged from 91.62% to 92.55% of correctly assigned specimens. By testing new and previously published sexing functions (Greeks, Polynesians, Guatemalans) on four available population samples (English, Indians from Amritsar, Indians from Varanasi, and data from the present study) we found that, for some combinations of tested and reference samples, the accuracy of the sex assessment may decrease even below the probability given by random sex assignment. Therefore, measurements of the clavicle should not be used for sex assessment of individual cases (both forensic and archeological) whose population origin is unknown. However, significant metric differences were also recorded among three different Greek samples (i.e. within a population). As a consequence, application of a sexing method generated from one Greek sample and applied to another Greek sample led to negligible reduction in the success of sex assessment, despite general similarities in ethnic origin (Greeks), generation structure and presumed social background of the samples. Therefore, we believe that future studies should focus on understanding the nature of the differences among within-population reference samples. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.
van Hemmen, Judy; Veltman, Dick J; Hoekzema, Elseline; Cohen-Kettenis, Peggy T; Dessens, Arianne B; Bakker, Julie
2016-03-01
Sex hormones, androgens in particular, are hypothesized to play a key role in the sexual differentiation of the human brain. However, possible direct effects of the sex chromosomes, that is, XX or XY, have not been well studied in humans. Individuals with complete androgen insensitivity syndrome (CAIS), who have a 46,XY karyotype but a female phenotype due to a complete androgen resistance, enable us to study the separate effects of gonadal hormones versus sex chromosomes on neural sex differences. Therefore, in the present study, we compared 46,XY men (n = 30) and 46,XX women (n = 29) to 46,XY individuals with CAIS (n = 21) on a mental rotation task using functional magnetic resonance imaging. Previously reported sex differences in neural activation during mental rotation were replicated in the control groups, with control men showing more activation in the inferior parietal lobe than control women. Individuals with CAIS showed a female-like neural activation pattern in the parietal lobe, indicating feminization of the brain in CAIS. Furthermore, this first neuroimaging study in individuals with CAIS provides evidence that sex differences in regional brain function during mental rotation are most likely not directly driven by genetic sex, but rather reflect gonadal hormone exposure. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.
Torimitsu, Suguru; Makino, Yohsuke; Saitoh, Hisako; Sakuma, Ayaka; Ishii, Namiko; Yajima, Daisuke; Inokuchi, Go; Motomura, Ayumi; Chiba, Fumiko; Yamaguchi, Rutsuko; Hashimoto, Mari; Hoshioka, Yumi; Iwase, Hirotaro
2015-12-01
Sex estimation of decomposed or skeletal remains is clearly important in forensic contexts. Recently, contemporary population-specific data has been obtained using multidetector computed tomography (MDCT) scanning. The main purpose of this study was to investigate skeletal pelvic dimorphism in a contemporary Japanese forensic sample and to quantify the accuracy of sex estimation using various pelvic measurements obtained from three-dimensional (3D) CT images. This study used a total of 208 cadavers (104 males, 104 females) of which postmortem CT scanning and subsequent forensic autopsy were conducted between December 2011 and August 2014. Eleven measurements of each pelvis were obtained from 3D CT reconstructed images that extracted only bone data. The measurements were analyzed using descriptive statistics and discriminant function analyses. All except one measurement were dimorphic in terms of sex differences. Univariate discriminant function analyses using these measurements provided sex classification accuracy rates of 62.0-98.1%. The subpubic angle was found to contribute most significantly to accurate sex estimation. Multivariate discriminant functions yielded sex prediction accuracy rates of 63.9-98.1%. In conclusion, the pelvic measurements obtained from 3D CT images of a contemporary Japanese population successfully demonstrated sexual dimorphism and may be useful for the estimation of skeletal sex in the field of forensic anthropology. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Sex differences in the course of schizophrenia across diverse regions of the world
Novick, Diego; Montgomery, William; Treuer, Tamas; Moneta, Maria Victoria; Haro, Josep Maria
2016-01-01
This study explores sex differences in the outcomes of patients with schizophrenia (clinical/functional remission and recovery) across diverse regions of the world (Northern Europe, Southern Europe, Central and Eastern Europe, Latin America, East Asia, and North Africa and the Middle East). Data (n=16,380 for this post hoc analysis) were taken from the World-Schizophrenia Health Outcomes Study. In most regions, females had a later age at first service contact for schizophrenia, a lower level of overall/negative symptom severity, lower rates of alcohol/substance abuse and paid employment, and higher percentages of having a spouse/partner and independent living. Overall, females had slightly higher rates of clinical remission (58.0% vs 51.8%), functional remission (22.8% vs 16.0%), and recovery (16.5% vs 16.0%) at 36 months (P<0.001 for all). This pattern was consistently observed in Southern Europe and Northern Europe even after controlling for baseline sex differences, but not in other regions. In Central and Eastern Europe, rates of clinical remission were higher in females at 36 months, but those of functional remission and recovery were similar between males and females. The opposite was observed for Latin America. In East Asia, sex differences were rarely observed for these outcomes. Finally, in North Africa and the Middle East, sex differences in these outcomes were pronounced only in regression analyses. These regional variations shed light on the importance of psychosocial and cultural factors and their effects on sex in the prognosis of schizophrenia. PMID:27881918
Sex-Role Preferences as a Function of Sex of Storyteller and Story Content.
ERIC Educational Resources Information Center
Lutes-Dunckley, Candida J.
1978-01-01
Out of 300 preschoolers, the children hearing a story in which traditional sex roles were reversed made more nontraditional choices among 15 pairs of traditional male/female activities than the children in either the traditional story or the no-story conditions. Differences between groups were greatest when members of the opposite sex conducted…
Hirnstein, Marco; Westerhausen, René; Korsnes, Maria S; Hugdahl, Kenneth
2013-01-01
Men are often believed to have a functionally more asymmetrical brain organization than women, but the empirical evidence for sex differences in lateralization is unclear to date. Over the years we have collected data from a vast number of participants using the same consonant-vowel dichotic listening task, a reliable marker for language lateralization. One dataset comprised behavioral data from 1782 participants (885 females, 125 non-right-handers), who were divided in four age groups (children <10 yrs, adolescents = 10-15 yrs, younger adults = 16-49 yrs, and older adults >50 yrs). In addition, we had behavioral and functional imaging (fMRI) data from another 104 younger adults (49 females, aged 18-45 yrs), who completed the same dichotic listening task in a 3T scanner. This database allowed us to comprehensively test whether there is a sex difference in functional language lateralization. Across all participants and in both datasets a right ear advantage (REA) emerged, reflecting left-hemispheric language lateralization. Accordingly, the fMRI data revealed a leftward asymmetry in superior temporal lobe language processing areas. In the N = 1782 dataset no main effect of sex but a significant sex by age interaction emerged: the REA increased with age in both sexes but as a result of an earlier onset in females the REA was stronger in female than male adolescents. In turn, male younger adults showed greater asymmetry than female younger adults (accounting for <1% of variance). There were no sex differences in children and older adults. The males in the fMRI dataset (N = 104) also had a greater REA than females (accounting for 4% of variance), but no sex difference emerged in the neuroimaging data. Handedness did not affect these findings. Taken together, our findings suggest that sex differences in language lateralization as assessed with dichotic listening exist, but they are (a) not necessarily reflected in fMRI data, (b) age-dependent and (c) relatively small. Copyright © 2012 Elsevier Ltd. All rights reserved.
Nota, Nienke M; Burke, Sarah M; den Heijer, Martin; Soleman, Remi S; Lambalk, Cornelis B; Cohen-Kettenis, Peggy T; Veltman, Dick J; Kreukels, Baudewijntje P
2017-12-01
It is hypothesized that transpeople show sex-atypical differentiation of the brain. Various structural neuroimaging studies provide support for this notion, but little is known about the sexual differentiation of functional resting-state networks in transpeople. In this study we therefore aimed to determine whether brain functional connectivity (FC) patterns in transpeople are sex-typical or sex-atypical, before and after the start of cross-sex hormone therapy (CHT). We acquired resting-state functional magnetic resonance data in 36 transpeople (22 with female sex assigned at birth), first during gonadal suppression, and again four months after start of CHT, and in 37 cisgender people (20 females), both sessions without any hormonal intervention. We used independent component analysis to identify the default mode network (DMN), salience network (SN), and left and right working memory network (WMN). These spatial maps were used for group comparisons. Within the DMN, SN, and left WMN similar FC patterns were found across groups. However, within the right WMN, cisgender males showed significantly greater FC in the right caudate nucleus than cisgender females. There was no such sex difference in FC among the transgender groups and they did not differ significantly from either of the cisgender groups. CHT (in transgender participants) and circulating sex steroids (in cisgender participants) did not affect FC. Our findings may suggest that cisgender males and females experience a dissimilar (early) differentiation of the right WMN and that such differentiation is less pronounced in transpeople. Copyright © 2017 Elsevier Masson SAS. All rights reserved.
Sex- and Tissue-specific Functions of Drosophila Doublesex Transcription Factor Target Genes
Clough, Emily; Jimenez, Erin; Kim, Yoo-Ah; Whitworth, Cale; Neville, Megan C.; Hempel, Leonie; Pavlou, Hania J.; Chen, Zhen-Xia; Sturgill, David; Dale, Ryan; Smith, Harold E.; Przytycka, Teresa M.; Goodwin, Stephen F.; Van Doren, Mark; Oliver, Brian
2014-01-01
Primary sex determination “switches” evolve rapidly, but Doublesex (DSX) related transcription factors (DMRTs) act downstream of these switches to control sexual development in most animal species. Drosophila dsx encodes female- and male-specific isoforms (DSXF and DSXM), but little is known about how dsx controls sexual development, whether DSXF and DSXM bind different targets, or how DSX proteins direct different outcomes in diverse tissues. We undertook genome-wide analyses to identify DSX targets using in vivo occupancy, binding site prediction, and evolutionary conservation. We find that DSXF and DSXM bind thousands of the same targets in multiple tissues in both sexes, yet these targets have sex- and tissue-specific functions. Interestingly, DSX targets show considerable overlap with targets identified for mouse DMRT1. DSX targets include transcription factors and signaling pathway components providing for direct and indirect regulation of sex-biased expression. PMID:25535918
Effects of male sex hormones on gender identity, sexual behavior, and cognitive function.
Zhu, Yuan-shan; Cai, Li-qun
2006-04-01
Androgens, the male sex hormones, play an essential role in male sexual differentiation and development. However, the influence of these sex hormones extends beyond their roles in sexual differentiation and development. In many animal species, sex hormones have been shown to be essential for sexual differentiation of the brain during development and for maintaining sexually dimorphic behavior throughout life. The principals of sex determination in humans have been demonstrated to be similar to other mammals. However, the hormonal influence on sexual dimorphic differences in the nervous system in humans, sex differences in behaviors, and its correlations with those of other mammals is still an emerging field. In this review, the roles of androgens in gender and cognitive function are discussed with the emphasis on subjects with androgen action defects including complete androgen insensitivity due to androgen receptor mutations and 5alpha-reductase-2 deficiency syndromes due to 5alpha-reductase-2 gene mutations. The issue of the complex interaction of nature versus nurture is addressed.
Yang, Wenjing; Cun, Lingli; Du, Xue; Yang, Junyi; Wang, Yanqiu; Wei, Dongtao; Zhang, Qinglin; Qiu, Jiang
2015-06-25
Although cognitive and personality studies have observed gender differences in narcissism, the neural bases of these differences remain unknown. The current study combined the voxel-based morphometry and resting state functional connectivity (rsFC) analyses to explore the sex-specific neural basis of narcissistic personality. The VBM results showed that the relationship between narcissistic personality and regional gray matter volume (rGMV) differed between sexes. Narcissistic scores had a significant positive correlation with the rGMV of the right SPL in females, but not in males. Further analyses were conducted to investigate the sex-specific relationship between rsFC and narcissism, using right SPL/frontal eye fields (FEF) as the seed regions (key nodes of the dorsal attention network, DAN). Interestingly, decreased anticorrelations between the right SPL/FEF and areas of the precuneus and middle frontal gyrus (key nodes of the the default mode network, DMN) were associated with higher narcissistic personality scores in males, whereas females showed the opposite tendency. The findings indicate that gender differences in narcissism may be associated with differences in the intrinsic and dynamic interplay between the internally-directed DMN and the externally-directed TPN. Morphometry and functional connectivity analyses can enhance our understanding of the neural basis of sex-specific narcissism.
Yang, Wenjing; Cun, Lingli; Du, Xue; Yang, Junyi; Wang, Yanqiu; Wei, Dongtao; Zhang, Qinglin; Qiu, Jiang
2015-01-01
Although cognitive and personality studies have observed gender differences in narcissism, the neural bases of these differences remain unknown. The current study combined the voxel-based morphometry and resting state functional connectivity (rsFC) analyses to explore the sex-specific neural basis of narcissistic personality. The VBM results showed that the relationship between narcissistic personality and regional gray matter volume (rGMV) differed between sexes. Narcissistic scores had a significant positive correlation with the rGMV of the right SPL in females, but not in males. Further analyses were conducted to investigate the sex-specific relationship between rsFC and narcissism, using right SPL/frontal eye fields (FEF) as the seed regions (key nodes of the dorsal attention network, DAN). Interestingly, decreased anticorrelations between the right SPL/FEF and areas of the precuneus and middle frontal gyrus (key nodes of the the default mode network, DMN) were associated with higher narcissistic personality scores in males, whereas females showed the opposite tendency. The findings indicate that gender differences in narcissism may be associated with differences in the intrinsic and dynamic interplay between the internally-directed DMN and the externally-directed TPN. Morphometry and functional connectivity analyses can enhance our understanding of the neural basis of sex-specific narcissism. PMID:26109334
Age and sex differences in paranormal beliefs: a response to Vitulli, Tipton, and Rowe (1999)
Irwin, H J
2000-04-01
Vitulli, Tipton, and Rowe (1999) report evidence of age and sex differences in the strength of paranormal beliefs. An alternative interpretation of their data is offered in terms of differential item functioning. It is suggested that respondents' interpretation of paranormal belief test items may vary with age and sex, and that such differences in the strength with which such beliefs are endorsed has not been conclusively established by Vitulli, et al.
Function and evolution of sex determination mechanisms, genes and pathways in insects
Gempe, Tanja; Beye, Martin
2011-01-01
Animals have evolved a bewildering diversity of mechanisms to determine the two sexes. Studies of sex determination genes – their history and function – in non-model insects and Drosophila have allowed us to begin to understand the generation of sex determination diversity. One common theme from these studies is that evolved mechanisms produce activities in either males or females to control a shared gene switch that regulates sexual development. Only a few small-scale changes in existing and duplicated genes are sufficient to generate large differences in sex determination systems. This review summarises recent findings in insects, surveys evidence of how and why sex determination mechanisms can change rapidly and suggests fruitful areas of future research. PMID:21110346
Sexual dimorphism in immune function changes during the annual cycle in house sparrows
NASA Astrophysics Data System (ADS)
Pap, Péter László; Czirják, Gábor Árpád; Vágási, Csongor István; Barta, Zoltán; Hasselquist, Dennis
2010-10-01
Difference between sexes in parasitism is a common phenomenon among birds, which may be related to differences between males and females in their investment into immune functions or as a consequence of differential exposure to parasites. Because life-history strategies change sex specifically during the annual cycle, immunological responses of the host aiming to reduce the impact of parasites may be sexually dimorphic. Despite the great complexity of the immune system, studies on immunoecology generally characterise the immune status through a few variables, often overlooking potentially important seasonal and gender effects. However, because of the differences in physiological and defence mechanisms among different arms of the immune system, we expect divergent responses of immune components to environmental seasonality. In male and female house sparrows ( Passer domesticus), we measured the major components of the immune system (innate, acquired, cellular and humoral) during four important life-history stages across the year: (1) mating, (2) breeding, (3) moulting and (4) during the winter capture and also following introduction to captivity in aviary. Different individuals were sampled from the same population during the four life cycle stages. We found that three out of eight immune variables showed a significant life cycle stage × sex interaction. The difference in immune response between the sexes was significant in five immune variables during the mating stage, when females had consistently stronger immune function than males, while variables varied generally non-significantly with sex during the remaining three life cycle stages. Our results show that the immune system is highly variable between life cycle stages and sexes, highlighting the potential fine tuning of the immune system to specific physiological states and environmental conditions.
Yang, Yunqiang; Li, Yang; Wu, Yeke; Gu, Yifei; Yin, Heng; Long, Hu; Shi, Bing; Zheng, Qian
2013-05-01
The aim of this study was to investigate the relevance of sex, age, and cleft type to velopharyngeal function after primary Sommerlad palatoplasty so as to improve velopharyngeal function after the procedure. Records of 503 patients with nonsyndromic cleft palate after primary Sommerlad palatoplasty were included in the retrospective study. Relevance between their velopharyngeal function and sex, age, and cleft type was analyzed. Statistical analysis was performed using SPSS 13.0 (SPSS Inc., Chicago, IL). There were no significant differences of velopharyngeal competence (VPC) rates between different sexes (P = 0.635). Specifically, VPC rates were significantly higher in younger-than-2-years groups than in older age groups (P < 0.05) and significantly lower in 6-years-or-older group (P < 0.05). No differences were found among 2- to 6-year-old groups (P > 0.05). The VPC rates were significantly lower in the bilateral complete cleft palate and the unilateral complete cleft palate than in the incomplete cleft palate before 2 years old (P < 0.05), whereas there were no significant differences totally (P = 0.875). Results showed that the disparity of the VPC rate among different cleft types would decrease with age. Moreover, results of multivariate logistic regression also indicated that operation age and cleft type are factors influencing velopharyngeal function. Primary palatoplasty should be completed before 2 years old, and the postoperative velopharygeal function will greatly decreases after 6 years old. The influence of cleft type on velopharyngeal function is limited to young patients. For those who have missed the best surgical timing, appropriate delay of operation age is reasonable, especially for patients with complete cleft palate. For patients 4 to 6 years old, the first choice is still simple palatoplasty no matter which cleft type they are classified into.
Varga, S; Kytöviita, M-M
2014-03-01
In several gynodioecious species, intermediate sex between female and hermaphrodite has been reported, but few studies have investigated fitness parameters of this intermediate phenotype. Here, we examined the interactions between plant sex and arbuscular mycorrhizal (AM) fungal species affecting the reproductive output of Geranium sylvaticum, a sexually polymorphic plant species with frequent intermediate sexes between females and hermaphrodites, using a common garden experiment. Flowering phenology, AM colonisation levels and several plant vegetative and reproductive parameters, including seed and pollen production, were measured. Differences among sexes were detected in flowering, fruit set, pollen production and floral size. The two AM species used in the present work had different effects on plant fitness parameters. One AM species increased female fitness through increasing seed number and seed mass, while the other species reduced seed mass in all sexes investigated. AM fungi did not affect intermediate and hermaphrodite pollen content in anthers. The three sexes in G. sylvaticum did not differ in their reproductive output in terms of total seed production, but hermaphrodites had potentially larger fathering ability than intermediates due to higher anther number. The ultimate female function--seed production--did not differ among the sexes, but one of the AM fungi used potentially decreased host plant fitness. In addition, in the intermediate sex, mycorrhizal symbiosis functioned similarly in females as in hermaphrodites. © 2013 German Botanical Society and The Royal Botanical Society of the Netherlands.
A Behavioral Comparison of Male and Female Adults with High Functioning Autism Spectrum Conditions
Lai, Meng-Chuan; Lombardo, Michael V.; Pasco, Greg; Ruigrok, Amber N. V.; Wheelwright, Sally J.; Sadek, Susan A.; Chakrabarti, Bhismadev; Baron-Cohen, Simon
2011-01-01
Autism spectrum conditions (ASC) affect more males than females in the general population. However, within ASC it is unclear if there are phenotypic sex differences. Testing for similarities and differences between the sexes is important not only for clinical assessment but also has implications for theories of typical sex differences and of autism. Using cognitive and behavioral measures, we investigated similarities and differences between the sexes in age- and IQ-matched adults with ASC (high-functioning autism or Asperger syndrome). Of the 83 (45 males and 38 females) participants, 62 (33 males and 29 females) met Autism Diagnostic Interview-Revised (ADI-R) cut-off criteria for autism in childhood and were included in all subsequent analyses. The severity of childhood core autism symptoms did not differ between the sexes. Males and females also did not differ in self-reported empathy, systemizing, anxiety, depression, and obsessive-compulsive traits/symptoms or mentalizing performance. However, adult females with ASC showed more lifetime sensory symptoms (p = 0.036), fewer current socio-communication difficulties (p = 0.001), and more self-reported autistic traits (p = 0.012) than males. In addition, females with ASC who also had developmental language delay had lower current performance IQ than those without developmental language delay (p<0.001), a pattern not seen in males. The absence of typical sex differences in empathizing-systemizing profiles within the autism spectrum confirms a prediction from the extreme male brain theory. Behavioral sex differences within ASC may also reflect different developmental mechanisms between males and females with ASC. We discuss the importance of the superficially better socio-communication ability in adult females with ASC in terms of why females with ASC may more often go under-recognized, and receive their diagnosis later, than males. PMID:21695147
Avian sex, sex chromosomes, and dosage compensation in the age of genomics.
Graves, Jennifer A Marshall
2014-04-01
Comparisons of the sex chromosome systems in birds and mammals are widening our view and deepening our understanding of vertebrate sex chromosome organization, function, and evolution. Birds have a very conserved ZW system of sex determination in which males have two copies of a large, gene-rich Z chromosome, and females have a single Z and a female-specific W chromosome. The avian ZW system is quite the reverse of the well-studied mammalian XY chromosome system, and evolved independently from different autosomal blocs. Despite the different gene content of mammal and bird sex chromosomes, there are many parallels. Genes on the bird Z and the mammal X have both undergone selection for male-advantage functions, and there has been amplification of male-advantage genes and accumulation of LINEs. The bird W and mammal Y have both undergone extensive degradation, but some birds retain early stages and some mammals terminal stages of the process, suggesting that the process is more advanced in mammals. Different sex-determining genes, DMRT1 and SRY, define the ZW and XY systems, but DMRT1 is involved in downstream events in mammals. Birds show strong cell autonomous specification of somatic sex differences in ZZ and ZW tissue, but there is growing evidence for direct X chromosome effects on sexual phenotype in mammals. Dosage compensation in birds appears to be phenotypically and molecularly quite different from X inactivation, being partial and gene-specific, but both systems use tools from the same molecular toolbox and there are some signs that galliform birds represent an early stage in the evolution of a coordinated system.
Sex differences in the neural mechanisms mediating addiction: a new synthesis and hypothesis
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
Ramsthaler, F; Kreutz, K; Verhoff, M A
2007-11-01
It has been generally accepted in skeletal sex determination that the use of metric methods is limited due to the population dependence of the multivariate algorithms. The aim of the study was to verify the applicability of software-based sex estimations outside the reference population group for which discriminant equations have been developed. We examined 98 skulls from recent forensic cases of known age, sex, and Caucasian ancestry from cranium collections in Frankfurt and Mainz (Germany) to determine the accuracy of sex determination using the statistical software solution Fordisc which derives its database and functions from the US American Forensic Database. In a comparison between metric analysis using Fordisc and morphological determination of sex, average accuracy for both sexes was 86 vs 94%, respectively, and males were identified more accurately than females. The ratio of the true test result rate to the false test result rate was not statistically different for the two methodological approaches at a significance level of 0.05 but was statistically different at a level of 0.10 (p=0.06). Possible explanations for this difference comprise different ancestry, age distribution, and socio-economic status compared to the Fordisc reference sample. It is likely that a discriminant function analysis on the basis of more similar European reference samples will lead to more valid and reliable sexing results. The use of Fordisc as a single method for the estimation of sex of recent skeletal remains in Europe cannot be recommended without additional morphological assessment and without a built-in software update based on modern European reference samples.
Sex Stereotypic Behavior in Infants: An Analysis of Social-Interpersonal Relationships.
ERIC Educational Resources Information Center
Lewis, Michael
This paper discusses the processes that are at work which produce some of the differences between male and female human beings. The sex of the child is an important attribute of the organism's identity. Before birth, parents express preferences for the sex of the unborn child and start providing names as a function of the sex of the child. Studies…
Campbell, Kimberley A; Hahn, Allison H; Congdon, Jenna V; Sturdy, Christopher B
2016-09-01
Sex differences have been identified in a number of black-capped chickadee vocalizations and in the chick-a-dee calls of other chickadee species [i.e., Carolina chickadees (Poecile carolinensis)]. In the current study, 12 acoustic features in black-capped chickadee chick-a-dee calls were investigated, including both frequency and duration measurements. Using permuted discriminant function analyses, these features were examined to determine if any features could be used to identify the sex of the caller. Only one note type (A notes) classified male and female calls at levels approaching significance. In particular, a permuted discriminant function analysis revealed that the start frequency of A notes best allowed for categorization between the sexes compared to any other acoustic parameter. This finding is consistent with previous research on Carolina chickadee chick-a-dee calls that found that the starting frequency differed between male- and female-produced A notes [Freeberg, Lucas, and Clucas (2003). J. Acoust. Soc. Am. 113, 2127-2136]. Taken together, these results and the results of studies with other chickadee species suggest that sex differences likely exist in the chick-a-dee call, specifically acoustic features in A notes, but that more complex features than those addressed here may be associated with the sex of the caller.
Gur, Ruben C.; Gur, Raquel E.
2016-01-01
While overwhelmingly behavior is similar in males and females, and correspondingly the brains are similar, sex differences permeate both brain and behavioral measures and these differences have been the focus of increasing scrutiny by neuroscientists. Here we describe milestones of over three decades of research in brain and behavior. This research was necessarily bound by available methodology, and we began by indirect behavioral indicators of brain function such as handedness. We proceeded to using neuropsychological batteries and then to structural and functional neuroimaging that provided the foundations of a cognitive neuroscience based computerized neurocognitive battery. Sex differences were apparent and consistent in neurocognitive measures, with females performing better on memory and social cognition tasks and males on spatial processing and motor speed. Sex differences were also prominent on all major brain parameters, including higher rates of cerebral blood flow, higher percent of gray matter tissue and higher inter-hemispheric connectivity in females compared to higher percent of white matter and greater intra-hemispheric connectivity, as well as higher glucose metabolism in limbic regions in males. Many of these differences are present in childhood but they become more prominent with adolescence, perhaps linked to puberty. Together they indicate complementarity between the sexes that would result in higher adaptive diversity. PMID:27870413
Sex-based differences in neurocognitive functioning in HIV-infected young adults.
Burlacu, Ruxandra; Umlauf, Anya; Luca, Anca; Gianella, Sara; Radoi, Roxana; Ruta, Simona M; Marcotte, Thomas D; Ene, Luminita; Achim, Cristian L
2018-01-14
Sex differences in cognition of HIV positive (HIV) patients are controversial. We aimed to investigate the relationship between cognition, HIV status, and sex, in a highly homogenous cohort of young Romanians parenterally infected during early childhood. In total, 250 HIV participants were compared with age-matched HIV negative (HIV) controls (n = 72) in a cross-sectional study. After standardized neurocognitive, psychological testing and medical evaluation, linear regression was used to assess the effect of sex and HIV on neurocognitive outcomes. Study participants were on average 23 years old with balanced sex distribution (% women = 52% vs. 43%). HIV were more educated (12.7 vs. 11.6 years, P = 0.002).HIV status was associated with a lower global performance (β = -0.22, P < 0.001), after controlling for age and education. HIV women had better previous and current HIV-associated markers. The effect of HIV on global cognition did not differ between sexes in most cognitive domains (β = 0.07, P = 0.14). An interaction between sex, HIV status, and cognitive functioning was found in the psychomotor domain. HIV women had worse motor skills than HIV women (β = -0.32, P < 0.001) suggesting a specific effect of HIV on motor functioning in women only. Moreover, current CD4 less than 200 cells/μl (P = 0.013) and longer time lived with CD4 less than 200 cells/μl (P = 0.023) were negatively correlated with the motor scaled score in women (β = -0.22, P = 0.034). Despite less advanced disease in women, long-term HIV infection has an equally detrimental effect on cognitive performances of both sexes, in all cognitive domains, except the psychomotor domain where women are preferentially affected.
Chao, Ariana M.; Loughead, James; Bakizada, Zayna M.; Hopkins, Christina M.; Geliebter, Allan; Gur, Ruben C.; Wadden, Thomas A.
2017-01-01
Sex and gender differences in food perceptions and eating behaviors have been reported in psychological and behavioral studies. The aim of this systematic review was to synthesize studies that examined sex/gender differences in neural correlates of food stimuli, as assessed by functional neuroimaging. Published studies to 2016 were retrieved and included if they used food or eating stimuli, assessed patients with functional magnetic resonance imaging (fMRI) or positron emission tomography (PET), and compared activation between males and females. Fifteen studies were identified. In response to visual food cues, females, compared to males, showed increased activation in the frontal, limbic, and striatal areas of the brain as well as the fusiform gyrus. Differences in neural response to gustatory stimuli were inconsistent. This body of literature suggests that females may be more reactive to visual food stimuli. However, findings are based on a small number of studies and additional research is needed to establish a more definitive explanation and conclusion. PMID:28371180
Lakes-Harlan, Reinhard; Devries, Thomas; Stölting, Heiko; Stumpner, Andreas
2014-01-01
Sensory modalities typically are important for both sexes, although sex-specific functional adaptations may occur frequently. This is true for hearing as well. Consequently, distinct behavioural functions were identified for the different insect hearing systems. Here we describe a first case, where a trait of an evolutionary novelty and a highly specialized hearing organ is adaptive in only one sex. The main function of hearing of the parasitoid fly Emblemasoma auditrix is to locate the host, males of the cicada species Okanagana rimosa, by their calling song. This task is performed by female flies, which deposit larvae into the host. We show that male E. auditrix possess a hearing sense as well. The morphology of the tympanal organ of male E. auditrix is rather similar to the female ear, which is 8% broader than the male ear. In both sexes the physiological hearing threshold is tuned to 5 kHz. Behavioural tests show that males are able to orient towards the host calling song, although phonotaxis often is incomplete. However, despite extensive observations in the field and substantial knowledge of the biology of E. auditrix, no potentially adaptive function of the male auditory sense has been identified. This unique hearing system might represent an intralocus sexual conflict, as the complex sense organ and the behavioural relevant neuronal network is adaptive for only one sex. The correlated evolution of the sense organ in both sexes might impose substantial constraints on the sensory properties of the ear. Similar constraints, although hidden, might also apply to other sensory systems in which behavioural functions differ between sexes.
Kadel, Sapana; Ainsua-Enrich, Erola; Hatipoglu, Ibrahim; Turner, Sean; Singh, Simar; Khan, Sohaib; Kovats, Susan
2018-02-01
Humans show significant sex differences in the incidence and severity of respiratory diseases, including asthma and virus infection. Sex hormones contribute to the female sex bias in type 2 inflammation associated with respiratory diseases, consistent with recent reports that female lungs harbor greater numbers of GATA-3-dependent group 2 innate lymphoid cells (ILC2s). In this study, we determined whether sex hormone levels govern sex differences in the numbers, phenotype, and function of ILC2s in the murine lung and bone marrow (BM). Our data show that lungs of female mice harbor significantly greater ILC2 numbers in homeostasis, in part due to a major subset of ILC2s lacking killer-cell lectin like receptor G1 (KLRG1), a population largely absent in male lungs. The KLRG1 - ILC2s were capable of type 2 cytokine production and increased with age after sexual maturity, suggesting that a unique functional subset exists in females. Experiments with gonadectomized mice or mice bearing either global or lymphocyte restricted estrogen receptor α ( Esr1 ) deficiency showed that androgens rather than estrogens regulated numbers of the KLRG1 - ILC2 subset and ILC2 functional capacity in the lung and BM, as well as levels of GATA-3 expression in BM ILC2s. Furthermore, the frequency of BM PLZF + ILC precursors was higher in males and increased by excess androgens, suggesting that androgens act to inhibit the transition of ILC precursors to ILC2s. Taken together, these data show that a functional subset of KLRG1 - ILC2s in females contributes to the sex bias in lung ILC2s that is observed after reproductive age.
Guigueno, Mélanie F; Sherry, David F; MacDougall-Shackleton, Scott A
2016-11-01
The song-control system in the brain of songbirds is important for the production and acquisition of song and exhibits both remarkable seasonal plasticity and some of the largest neural sex differences observed in vertebrates. We measured sex and seasonal differences in two nuclei of the song-control system of brood-parasitic brown-headed cowbirds (Molothrus ater) and closely-related non-parasitic red-winged blackbirds (Agelaius phoeniceus). These species differ in both the development and function of song. Brown-headed cowbirds have a larger sex difference in song than red-winged blackbirds. Female cowbirds never sing, whereas female blackbirds do though much less than males. In cowbirds, song primarily functions in mate choice and males modify their song as they approach sexual maturity and interact with females. In red-winged blackbirds, song is used primarily in territorial defence and is crystalized earlier in life. We found that the HVC was more likely to be discernable in breeding female blackbirds than in breeding female cowbirds. Compared to males, females had a smaller HVC and a smaller robust nucleus of the arcopallium (RA). However, females had higher doublecortin immunoreactivity (DCX+) in HVC, a measure of neurogenesis. Consistent with sex differences in song, the sex difference in RA volume was greater in cowbirds than in blackbirds. Males of both species had a smaller HVC with higher DCX+ in post-breeding condition than in breeding condition when song is more plastic. Sex and seasonal differences in the song-control system were closely related to variation in song in these two icterid songbirds. © 2016 Wiley Periodicals, Inc. Develop Neurobiol 76: 1226-1240, 2016. © 2016 Wiley Periodicals, Inc.
Chaychi, Samaneh; Polosa, Anna; Lachapelle, Pierre
2015-01-01
Purpose Biological sex and age are considered as two important factors that may influence the function and structure of the retina, an effect that might be governed by sexual hormones such as estrogen. The purpose of this study was to delineate the influence that biological sex and age exert on the retinal function and structure of rodents and also clarify the effect that the estrus cycle might exert on the retinal function of female rats. Method The retinal function of 50 normal male and female albino Sprague-Dawley (SD) rats was investigated with the electroretinogram (ERG) at postnatal day (P) 30, 60, 100, 200, and 300 (n = 5–6 male and female rats/age). Following the ERG recording sessions, retinal histology was performed in both sexes. In parallel, the retinal function of premenopausal and menopausal female rats aged P540 were also compared. Results Sex and age-related changes in retinal structure and function were observed in our animal model. However, irrespective of age, no significant difference was observed in ERG and retinal histology obtained from male and female rats. Notwithstanding the above we did however notice that between P60 and P200 there was a gradual increase in ERG amplitudes of female rats compared to males. Furthermore, the ERG of premenopausal female rats aged 18 months old (P540) was larger compared to age-matched menopausal female rats as well as that of male rats. Conclusion Our results showed that biological sex and age can influence the retinal function and structure of albino SD rats. Furthermore, we showed that cycled female rats have better retinal function compared to the menopausal female rats suggesting a beneficial effect of the estrus cycle on the retinal function. PMID:26317201
Callahan, Damien M; Bedrin, Nicholas G; Subramanian, Meenakumari; Berking, James; Ades, Philip A; Toth, Michael J; Miller, Mark S
2014-06-15
Age-related loss of skeletal muscle mass and function is implicated in the development of disease and physical disability. However, little is known about how age affects skeletal muscle structure at the cellular and ultrastructural levels or how such alterations impact function. Thus we examined skeletal muscle structure at the tissue, cellular, and myofibrillar levels in young (21-35 yr) and older (65-75 yr) male and female volunteers, matched for habitual physical activity level. Older adults had smaller whole muscle tissue cross-sectional areas (CSAs) and mass. At the cellular level, older adults had reduced CSAs in myosin heavy chain II (MHC II) fibers, with no differences in MHC I fibers. In MHC II fibers, older men tended to have fewer fibers with large CSAs, while older women showed reduced fiber size across the CSA range. Older adults showed a decrease in intermyofibrillar mitochondrial size; however, the age effect was driven primarily by women (i.e., age by sex interaction effect). Mitochondrial size was inversely and directly related to isometric tension and myosin-actin cross-bridge kinetics, respectively. Notably, there were no intermyofibrillar or subsarcolemmal mitochondrial fractional content or myofilament ultrastructural differences in the activity-matched young and older adults. Collectively, our results indicate age-related reductions in whole muscle size do not vary by sex. However, age-related structural alterations at the cellular and subcellular levels are different between the sexes and may contribute to different functional phenotypes in ways that modulate sex-specific reductions in physical capacity with age. Copyright © 2014 the American Physiological Society.
Sex differences in autonomic function following maximal exercise.
Kappus, Rebecca M; Ranadive, Sushant M; Yan, Huimin; Lane-Cordova, Abbi D; Cook, Marc D; Sun, Peng; Harvey, I Shevon; Wilund, Kenneth R; Woods, Jeffrey A; Fernhall, Bo
2015-01-01
Heart rate variability (HRV), blood pressure variability, (BPV) and heart rate recovery (HRR) are measures that provide insight regarding autonomic function. Maximal exercise can affect autonomic function, and it is unknown if there are sex differences in autonomic recovery following exercise. Therefore, the purpose of this study was to determine sex differences in several measures of autonomic function and the response following maximal exercise. Seventy-one (31 males and 40 females) healthy, nonsmoking, sedentary normotensive subjects between the ages of 18 and 35 underwent measurements of HRV and BPV at rest and following a maximal exercise bout. HRR was measured at minute one and two following maximal exercise. Males have significantly greater HRR following maximal exercise at both minute one and two; however, the significance between sexes was eliminated when controlling for VO2 peak. Males had significantly higher resting BPV-low-frequency (LF) values compared to females and did not significantly change following exercise, whereas females had significantly increased BPV-LF values following acute maximal exercise. Although males and females exhibited a significant decrease in both HRV-LF and HRV-high frequency (HF) with exercise, females had significantly higher HRV-HF values following exercise. Males had a significantly higher HRV-LF/HF ratio at rest; however, both males and females significantly increased their HRV-LF/HF ratio following exercise. Pre-menopausal females exhibit a cardioprotective autonomic profile compared to age-matched males due to lower resting sympathetic activity and faster vagal reactivation following maximal exercise. Acute maximal exercise is a sufficient autonomic stressor to demonstrate sex differences in the critical post-exercise recovery period.
Different perspectives on the sex-attachment link: towards an emotion-motivational account.
Dewitte, Marieke
2012-01-01
Although the link between sex and attachment was made decades ago (Hazan & Shaver, 1987), theories on sexual and attachment functioning have been developed in relative isolation. Recent efforts to integrate both literatures have been complicated by the fact that the sex-attachment link has been approached from very different perspectives, including biological, evolutionary, developmental, cognitive, and social psychology approaches. Also, at the empirical level, research on sex and attachment lacks overarching synthesis. This article gives an overview of the most important theoretical ideas and empirical insights on sex and attachment. It starts with describing general models that approach the sex-attachment link from an evolutionary and neurobiological perspective. Then, it summarizes theoretical and empirical ideas of attachment theory and describes how attachment style differences are manifested in intimate and sexual relationships. Research so far has been limited to studying the predicted link between sex and attachment in terms of broad descriptives, and it would benefit the literature to specify the processes and pathways that mediate the sex-attachment link. After a short discussion of the functional similarities between the sexual and the attachment systems, the article describes some specific--dynamical--models that focus on the emotional and cognitive-motivational processes through which attachment schemas influence sexual experiences. Such an emotion-motivational perspective on sex and attachment can help to organize theoretical ideas and empirical findings and eventually promote an integrative view on how attachment dynamics can interact with sexual experiences.
Ideal resuscitation pressure for uncontrolled hemorrhagic shock in different ages and sexes of rats
2013-01-01
Introduction Our previous studies demonstrated that 50-60 mmHg mean arterial blood pressure was the ideal target hypotension for uncontrolled hemorrhagic shock during the active hemorrhage in sexually mature rats. The ideal target resuscitation pressure for immature and older rats has not been determined. Methods To elucidate this issue, using uncontrolled hemorrhagic-shock rats of different ages and sexes (6 weeks, 14 weeks and 1.5 years representing pre-adult, adult and older rats, respectively), the resuscitation effects of different target pressures (40, 50, 60, 70 and 80 mmHg) on uncontrolled hemorrhagic shock during active hemorrhage and the age and sex differences were observed. Results Different target resuscitation pressures had different resuscitation outcomes for the same age and sex of rats. The optimal target resuscitation pressures for 6-week-old, 14-week-old and 1.5-year-old rats were 40 to 50 mmHg, 50 to 60 mmHg and 70 mmHg respectively. Ideal target resuscitation pressures were significantly superior to other resuscitation pressures in improving the hemodynamics, blood perfusion, organ function and animal survival of uncontrolled hemorrhagic-shock rats (P < 0.01). For same target resuscitation pressures, the beneficial effect on hemorrhagic shock had a significant age difference (P < 0.01) but no sex difference (P > 0.05). Different resuscitation pressures had no effect on coagulation function. Conclusion Hemorrhagic-shock rats at different ages have different target resuscitation pressures during active hemorrhage. The ideal target resuscitation hypotension for 6-week-old, 14-week-old and 1.5-year-old rats was 40 to 50 mmHg, 50 to 60 mmHg and 70 mmHg, respectively. Their resuscitation effects have significant age difference but had no sex difference. PMID:24020401
Wang, Xu; Werren, John H.; Clark, Andrew G.
2015-01-01
There is extraordinary diversity in sexual dimorphism (SD) among animals, but little is known about its epigenetic basis. To study the epigenetic architecture of SD in a haplodiploid system, we performed RNA-seq and whole-genome bisulfite sequencing of adult females and males from two closely related parasitoid wasps, Nasonia vitripennis and Nasonia giraulti. More than 75% of expressed genes displayed significantly sex-biased expression. As a consequence, expression profiles are more similar between species within each sex than between sexes within each species. Furthermore, extremely male- and female-biased genes are enriched for totally different functional categories: male-biased genes for key enzymes in sex-pheromone synthesis and female-biased genes for genes involved in epigenetic regulation of gene expression. Remarkably, just 70 highly expressed, extremely male-biased genes account for 10% of all transcripts in adult males. Unlike expression profiles, DNA methylomes are highly similar between sexes within species, with no consistent sex differences in methylation found. Therefore, methylation changes cannot explain the extensive level of sex-biased gene expression observed. Female-biased genes have smaller sequence divergence between species, higher conservation to other hymenopterans, and a broader expression range across development. Overall, female-biased genes have been recruited from genes with more conserved and broadly expressing “house-keeping” functions, whereas male-biased genes are more recently evolved and are predominately testis specific. In summary, Nasonia accomplish a striking degree of sex-biased expression without sex chromosomes or epigenetic differences in methylation. We propose that methylation provides a general signal for constitutive gene expression, whereas other sex-specific signals cause sex-biased gene expression. PMID:26100871
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 emotional perception: Meta analysis of divergent activation.
Filkowski, Megan M; Olsen, Rachel M; Duda, Bryant; Wanger, Timothy J; Sabatinelli, Dean
2017-02-15
Behavioral and physiological sex differences in emotional reactivity are well documented, yet comparatively few neural differences have been identified. Here we apply quantitative activation likelihood estimation (ALE) meta-analysis across functional brain imaging studies that each reported clusters of activity differentiating men and women as they participated in emotion-evoking tasks in the visual modality. This approach requires the experimental paradigm to be balanced across the sexes, and thus may provide greater clarity than previous efforts. Results across 56 emotion-eliciting studies (n=1907) reveal distinct activation in the medial prefrontal cortex, anterior cingulate cortex, frontal pole, and mediodorsal nucleus of the thalamus in men relative to women. Women show distinct activation in bilateral amygdala, hippocampus, and regions of the dorsal midbrain including the periaqueductal gray/superior colliculus and locus coeruleus. While some clusters are consistent with prevailing perspectives on the foundations of sex differences in emotional reactivity, thalamic and brainstem regions have not previously been highlighted as sexually divergent. These data strongly support the need to include sex as a factor in functional brain imaging studies of emotion, and to extend our investigative focus beyond the cortex. Copyright © 2016 Elsevier Inc. All rights reserved.
Heidari, Masumeh; Aminshokravi, Farkhondeh; Zayeri, Farid; Azin, Seyed Ali
2018-01-01
The aim of this study was to evaluate the impact of husbands' participation in sexual education on sexual function during pregnancy. This quasi experimental study was conducted on 123 couples who were divided in two intervention (A: couples, B: pregnant women) and one control (C) groups. Group A couples received sex education, Group B women received sex education without their spouses, and Group C women received routine prenatal care without sex education. Sexual functions of couples were assessed by Female Sexual Function Index (FSFI) and International Index Erectile Function (IIEF) questionnaires, before sex education, four weeks after the intervention, at the end of the second trimester and at the end of the third trimester. Mean total scores of FSFI and IIEF were not different at baseline in three groups. Repeated measure analysis showed significant differences between groups (A and B with C) in the mean total scores of FSFI and IIEF during the third trimester. The mean total scores of the two intervention groups of A and B were not significant. According to the results of the present study, promoting the sexual function of pregnant women needs to include the sex education on prenatal care. Whereas spouses' participation was suggested to have a great role in the effectiveness and strengthening of the education in various studies, this study showed that the lack of spouses' participation for whatever reasons may lead to the same results of previous studies which emphasized the necessity of spouses' participation.
Sex differences in cerebral palsy incidence and functional ability: a total population study.
Chounti, A; Hägglund, G; Wagner, P; Westbom, L
2013-07-01
To describe gender difference in a total population of children with cerebral palsy (CP), related to subtype, gross and fine motor function, and to compare CP incidence trends in girls and boys. All 590 children with CP born in southern Sweden 1990-2005 were included. CP subtype was classified according to the Surveillance of Cerebral Palsy in Europe, gross motor function according to Gross Motor Function Classification System (GMFCS) and manual ability according to Manual Ability Classification System (MACS). Trends in CP incidence by birth year were analysed using Poisson regression modelling. There was a male predominance in all levels of GMFCS except level II, in all levels of MACS and in all CP subtypes except ataxic CP. There was no statistically significant difference between males and females regarding gross motor function or manual ability. The CP incidence trends in boys compared with girls did not change during the period 1990-2005. No equalization was detected in the incidence of CP between girls and boys during recent years in this total population. We could not confirm any consistent sex difference in motor function levels. Male sex is a risk factor for CP. ©2013 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.
Early sex differences are not autism-specific: A Baby Siblings Research Consortium (BSRC) study.
Messinger, Daniel S; Young, Gregory S; Webb, Sara Jane; Ozonoff, Sally; Bryson, Susan E; Carter, Alice; Carver, Leslie; Charman, Tony; Chawarska, Katarzyna; Curtin, Suzanne; Dobkins, Karen; Hertz-Picciotto, Irva; Hutman, Ted; Iverson, Jana M; Landa, Rebecca; Nelson, Charles A; Stone, Wendy L; Tager-Flusberg, Helen; Zwaigenbaum, Lonnie
2015-01-01
The increased male prevalence of autism spectrum disorder (ASD) may be mirrored by the early emergence of sex differences in ASD symptoms and cognitive functioning. The female protective effect hypothesis posits that ASD recurrence and symptoms will be higher among relatives of female probands. This study examined sex differences and sex of proband differences in ASD outcome and in the development of ASD symptoms and cognitive functioning among the high-risk younger siblings of ASD probands and low-risk children. Prior to 18 months of age, 1824 infants (1241 high-risk siblings, 583 low-risk) from 15 sites were recruited. Hierarchical generalized linear model (HGLM) analyses of younger sibling and proband sex differences in ASD recurrence among high-risk siblings were followed by HGLM analyses of sex differences and group differences (high-risk ASD, high-risk non-ASD, and low-risk) on the Mullen Scales of Early Learning (MSEL) subscales (Expressive and Receptive Language, Fine Motor, and Visual Reception) at 18, 24, and 36 months and Autism Diagnostic Observation Schedule (ADOS) domain scores (social affect (SA) and restricted and repetitive behaviors (RRB)) at 24 and 36 months. Of 1241 high-risk siblings, 252 had ASD outcomes. Male recurrence was 26.7 % and female recurrence 10.3 %, with a 3.18 odds ratio. The HR-ASD group had lower MSEL subscale scores and higher RRB and SA scores than the HR non-ASD group, which had lower MSEL subscale scores and higher RRB scores than the LR group. Regardless of group, males obtained lower MSEL subscale scores, and higher ADOS RRB scores, than females. There were, however, no significant interactions between sex and group on either the MSEL or ADOS. Proband sex did not affect ASD outcome, MSEL subscale, or ADOS domain scores. A 3.2:1 male:female odds ratio emerged among a large sample of prospectively followed high-risk siblings. Sex differences in cognitive performance and repetitive behaviors were apparent not only in high-risk children with ASD, but also in high-risk children without ASD and in low-risk children. Sex differences in young children with ASD do not appear to be ASD-specific but instead reflect typically occurring sex differences seen in children without ASD. Results did not support a female protective effect hypothesis.
Sex differences in adipose tissue
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 and strain dependent differences in mucosal immunology and microbiota composition in mice.
Elderman, Marlies; Hugenholtz, Floor; Belzer, Clara; Boekschoten, Mark; van Beek, Adriaan; de Haan, Bart; Savelkoul, Huub; de Vos, Paul; Faas, Marijke
2018-06-18
A dysbiosis in the intestinal microbiome plays a role in the pathogenesis of several immunological diseases. These diseases often show a sex bias, suggesting sex differences in immune responses and in the intestinal microbiome. We hypothesized that sex differences in immune responses are associated with sex differences in microbiota composition. Fecal microbiota composition (MITchip), mRNA expression in intestinal tissue (microarray), and immune cell populations in mesenteric lymph nodes (MLNs) were studied in male and female mice of two mouse strains (C57B1/6OlaHsd and Balb/cOlaHsd). Transcriptomics and microbiota data were combined to identify bacterial species which may potentially be related to sex-specific differences in intestinal immune related genes. We found clear sex differences in intestinal microbiota species, diversity, and richness in healthy mice. However, the nature of the sex effects appeared to be determined by the mouse strain as different bacterial species were enriched in males and females of the two strains. For example, Lactobacillus plantarum and Bacteroides distasonis were enriched in B6 females as compared to B6 males, while Bifidobacterium was enriched BALB/c females as compared to BALB/c males. The strain-dependent sex effects were also observed in the expression of immunological genes in the colon. We found that the abundance of various bacteria (e.g., Clostridium leptum et rel.) which were enriched in B6 females positively correlated with the expression of several genes (e.g., Il-2rb, Ccr3, and Cd80) which could be related to immunological functions, such as inflammatory responses and migration of leukocytes. The abundance of several bacteria (e.g., Faecalibacterium prausnitzii et rel. and Coprobacillus et rel.- Clostridium ramosum et rel.) which were enriched in BALB/c males positively correlated to the expression of several genes (e.g., Apoe, Il-1b, and Stat4) related to several immunological functions, such as proliferation and quantity of lymphocytes. The net result was the same, since both mouse strains showed similar sex induced differences in immune cell populations in the MLNs. Our data suggests a correlation between microbiota and intestinal immune populations in a sex and strain-specific way. These findings may contribute to the development of more sex and genetic specific treatments for intestinal-related disorders.
Differential item functioning by sex and race in the Hogan Personality Inventory.
Sheppard, Richard; Han, Kyunghee; Colarelli, Stephen M; Dai, Guangdong; King, Daniel W
2006-12-01
The authors examined measurement bias in the Hogan Personality Inventory by investigating differential item functioning (DIF) across sex and two racial groups (Caucasian and Black). The sample consisted of 1,579 Caucasians (1,023 men, 556 women) and 523 Blacks (321 men, 202 women) who were applying for entry-level, unskilled jobs in factories. Although the group mean differences were trivial, more than a third of the items showed DIF by sex (38.4%) and by race (37.3%). A content analysis of potentially biased items indicated that the themes of items displaying DIF were slightly more cohesive for sex than for race. The authors discuss possible explanations for differing clustering tendencies of items displaying DIF and some practical and theoretical implications of DIF in the development and interpretation of personality inventories.
Cuevas, Kimberly; Calkins, Susan D.; Bell, Martha Ann
2015-01-01
Executive functions (EFs) are linked with optimal cognitive and social-emotional development. Despite behavioral evidence of sex differences in early childhood EF, little is known about potential sex differences in corresponding brain-behavior associations. The present study examined changes in 4-year-olds’ 6–9 Hz EEG power in response to increased executive processing demands (i.e., “Stroop-like” vs. “non-Stroop” day-night tasks). Although there were no sex differences in task performance, an examination of multiple scalp electrode sites revealed that boys exhibited more widespread changes in EEG power as compared to girls. Further, multiple regression analyses controlling for maternal education and non-EF performance indicated that individual differences in boys’ and girls’ EF performance were associated with different frontal neural correlates (i.e., different frontal scalp sites and different measures of EEG power). These data reveal valuable information concerning sex differences in the neural systems underlying executive processing during early childhood. PMID:26681615
Hjelmervik, Helene; Hausmann, Markus; Osnes, Berge; Westerhausen, René; Specht, Karsten
2014-01-01
To what degree resting state fMRI is stable or susceptible to internal mind states of the individual is currently an issue of debate. To address this issue, the present study focuses on sex differences and investigates whether resting state fMRI is stable in men and women or changes within relative short-term periods (i.e., across the menstrual cycle). Due to the fact that we recently reported menstrual cycle effects on cognitive control based on data collected during the same sessions, the current study is particularly interested in fronto-parietal resting state networks. Resting state fMRI was measured in sixteen women during three different cycle phases (menstrual, follicular, and luteal). Fifteen men underwent three sessions in corresponding time intervals. We used independent component analysis to identify four fronto-parietal networks. The results showed sex differences in two of these networks with women exhibiting higher functional connectivity in general, including the prefrontal cortex. Menstrual cycle effects on resting states were non-existent. It is concluded that sex differences in resting state fMRI might reflect sexual dimorphisms in the brain rather than transitory activating effects of sex hormones on the functional connectivity in the resting brain.
Hjelmervik, Helene; Hausmann, Markus; Osnes, Berge; Westerhausen, René; Specht, Karsten
2014-01-01
To what degree resting state fMRI is stable or susceptible to internal mind states of the individual is currently an issue of debate. To address this issue, the present study focuses on sex differences and investigates whether resting state fMRI is stable in men and women or changes within relative short-term periods (i.e., across the menstrual cycle). Due to the fact that we recently reported menstrual cycle effects on cognitive control based on data collected during the same sessions, the current study is particularly interested in fronto-parietal resting state networks. Resting state fMRI was measured in sixteen women during three different cycle phases (menstrual, follicular, and luteal). Fifteen men underwent three sessions in corresponding time intervals. We used independent component analysis to identify four fronto-parietal networks. The results showed sex differences in two of these networks with women exhibiting higher functional connectivity in general, including the prefrontal cortex. Menstrual cycle effects on resting states were non-existent. It is concluded that sex differences in resting state fMRI might reflect sexual dimorphisms in the brain rather than transitory activating effects of sex hormones on the functional connectivity in the resting brain. PMID:25057823
Sex-role identification of normal adolescent males and females as related to school achievement.
Hock, R A; Curry, J F
1983-12-01
The historical view of masculinity/femininity posited essentially bipolar opposites, with the presence of one set of characteristics precluding the other. More recent studies of sex-role stereotypes have defined sexual orientation within clusters of socially desirable attributes which males and females perceive as differentiating males from females. This view negates the contention that psychological sex roles are composed of bipolar opposites, and concludes that the constructs of masculinity and femininity are independent dimensions rather than a single bipolar dimension. Little is known about the sex-role functioning of adolescents, yet it is during adolescence that qualitative shifts occur in interpersonal relationships and concurrent changes occur in cognitive functioning, with adolescents shifting toward hypothetical thinking and abstract ideal notions. In view of these changes, much can be learned about adult functioning by studying the sex-role perceptions of adolescents related to familial and social variables. This study examines the sex-role perceptions that adolescents hold of fathers, mothers, ideal males, ideal females, and selves. Differences exist between male and female adolescents, and significant linkages exist between sex-role identification and academic achievement.
Quintela, T; Marcelino, H; Deery, M J; Feret, R; Howard, J; Lilley, K S; Albuquerque, T; Gonçalves, I; Duarte, A C; Santos, C R A
2016-01-01
The choroid plexus (CP) epithelium is a unique structure in the brain that forms an interface between the peripheral blood and the cerebrospinal fluid (CSF), which is mostly produced by the CP itself. Because the CP transcriptome is regulated by the sex hormone background, the present study compared gene/protein expression profiles in the CP and CSF from male and female rats aiming to better understand sex-related differences in CP functions and brain physiology. We used data previously obtained by cDNA microarrays to compare the CP transcriptome between male and female rats, and complemented these data with the proteomic analysis of the CSF of castrated and sham-operated males and females. Microarray analysis showed that 17 128 and 17 002 genes are expressed in the male and female CP, which allowed the functional annotation of 141 and 134 pathways, respectively. Among the most expressed genes, canonical pathways associated with mitochondrial dysfunctions and oxidative phosphorylation were the most prominent, whereas the most relevant molecular and cellular functions annotated were protein synthesis, cellular growth and proliferation, cell death and survival, molecular transport, and protein trafficking. No significant differences were found between males and females regarding these pathways. Seminal functions of the CP differentially regulated between sexes were circadian rhythm signalling, as well as several canonical pathways related to stem cell differentiation, metabolism and the barrier function of the CP. The proteomic analysis identified five down-regulated proteins in the CSF samples from male rats compared to females and seven proteins exhibiting marked variation in the CSF of gonadectomised males compared to sham animals, whereas no differences were found between sham and ovariectomised females. These data clearly show sex-related differences in CP gene expression and CSF protein composition that may impact upon neurological diseases. © 2015 British Society for Neuroendocrinology.
Sex determination in insects: a binary decision based on alternative splicing.
Salz, Helen K
2011-08-01
The gene regulatory networks that control sex determination vary between species. Despite these differences, comparative studies in insects have found that alternative splicing is reiteratively used in evolution to control expression of the key sex-determining genes. Sex determination is best understood in Drosophila where activation of the RNA binding protein-encoding gene Sex-lethal is the central female-determining event. Sex-lethal serves as a genetic switch because once activated it controls its own expression by a positive feedback splicing mechanism. Sex fate choice in is also maintained by self-sustaining positive feedback splicing mechanisms in other dipteran and hymenopteran insects, although different RNA binding protein-encoding genes function as the binary switch. Studies exploring the mechanisms of sex-specific splicing have revealed the extent to which sex determination is integrated with other developmental regulatory networks. Copyright © 2011 Elsevier Ltd. All rights reserved.
Yoshida, Kuniko; Obokata, Masaru; Kurosawa, Koji; Sorimachi, Hidemi; Kurabayashi, Masahiko; Negishi, Kazuaki
2016-10-01
Embolic stroke in atrial fibrillation is more prevalent in women than in men, yet the basis for this difference remains unclear. This study seeks to elucidate whether there are any sex differences in the relationships between stroke risk (CHADS 2 score, CHA 2 DS 2 -VASc score without a sex category, and estimated stroke rate) and left atrial (LA) anatomy or mechanics in patients with atrial fibrillation. LA emptying fraction and global peak atrial longitudinal strain were assessed in 414 subjects with paroxysmal or persistent atrial fibrillation (156 women and 258 men). Linear regression models with an interaction term were performed to test the effect of sex difference on associations between the embolic risk and LA function or anatomy. Sensitivity analyses were performed in 228 age, heart rate, and rhythm-matched subjects (114 women and men). Women were older and had larger LA volumes and lower LA mechanics than men. Significant negative association between the CHADS 2 score and LA emptying fraction was only demonstrated in women with a significant interaction between sexes. Similar significant interactions were found in global peak atrial longitudinal strain but not in LA volume. These findings were corroborated in the comparisons against CHA 2 DS 2 -VASc score without a sex category and the estimated stroke rate. Sensitivity analyses in the matched subgroup also confirmed the robustness of these sex differences in LA emptying fraction, but less so in global peak atrial longitudinal strain. Significant sex interactions on the association between global LA function and risk stratification schemes exist, which may be a reason for the higher prevalence of embolic stroke in women. © 2016 American Heart Association, Inc.
The behavioural consequences of sex reversal in dragons
Li, Hong; Holleley, Clare E.; Elphick, Melanie; Georges, Arthur
2016-01-01
Sex differences in morphology, physiology, and behaviour are caused by sex-linked genes, as well as by circulating sex-steroid levels. Thus, a shift from genotypic to environmental sex determination may create an organism that exhibits a mixture of male-like and female-like traits. We studied a lizard species (Central Bearded Dragon, Pogona vitticeps), in which the high-temperature incubation of eggs transforms genetically male individuals into functional females. Although they are reproductively female, sex-reversed dragons (individuals with ZZ genotype reversed to female phenotype) resemble genetic males rather than females in morphology (relative tail length), general behaviour (boldness and activity level), and thermoregulatory tactics. Indeed, sex-reversed ‘females’ are more male-like in some behavioural traits than are genetic males. This novel phenotype may impose strong selection on the frequency of sex reversal within natural populations, facilitating rapid shifts in sex-determining systems. A single period of high incubation temperatures (generating thermally induced sex reversal) can produce functionally female individuals with male-like (or novel) traits that enhance individual fitness, allowing the new temperature-dependent sex-determining system to rapidly replace the previous genetically based one.
Distributed effects of biological sex define sex-typical motor behavior in Caenorhabditis elegans.
Mowrey, William R; Bennett, Jessica R; Portman, Douglas S
2014-01-29
Sex differences in shared behaviors (for example, locomotion and feeding) are a nearly universal feature of animal biology. Though these behaviors may share underlying neural programs, their kinematics can exhibit robust differences between males and females. The neural underpinnings of these differences are poorly understood because of the often-untested assumption that they are determined by sex-specific body morphology. Here, we address this issue in the nematode Caenorhabditis elegans, which features two sexes with distinct body morphologies but similar locomotor circuitry and body muscle. Quantitative behavioral analysis shows that C. elegans and related nematodes exhibit significant sex differences in the dynamics and geometry of locomotor body waves, such that the male is generally faster. Using a recently proposed model of locomotor wave propagation, we show that sex differences in both body mechanics and the intrinsic dynamics of the motor system can contribute to kinematic differences in distinct mechanical contexts. By genetically sex-reversing the properties of specific tissues and cells, however, we find that sex-specific locomotor frequency in C. elegans is determined primarily by the functional modification of shared sensory neurons. Further, we find that sexual modification of body wall muscle together with the nervous system is required to alter body wave speed. Thus, rather than relying on a single focus of modification, sex differences in motor dynamics require independent modifications to multiple tissue types. Our results suggest shared motor behaviors may be sex-specifically optimized though distributed modifications to several aspects of morphology and physiology.
Distributed Effects of Biological Sex Define Sex-Typical Motor Behavior in Caenorhabditis elegans
Mowrey, William R.; Bennett, Jessica R.
2014-01-01
Sex differences in shared behaviors (for example, locomotion and feeding) are a nearly universal feature of animal biology. Though these behaviors may share underlying neural programs, their kinematics can exhibit robust differences between males and females. The neural underpinnings of these differences are poorly understood because of the often-untested assumption that they are determined by sex-specific body morphology. Here, we address this issue in the nematode Caenorhabditis elegans, which features two sexes with distinct body morphologies but similar locomotor circuitry and body muscle. Quantitative behavioral analysis shows that C. elegans and related nematodes exhibit significant sex differences in the dynamics and geometry of locomotor body waves, such that the male is generally faster. Using a recently proposed model of locomotor wave propagation, we show that sex differences in both body mechanics and the intrinsic dynamics of the motor system can contribute to kinematic differences in distinct mechanical contexts. By genetically sex-reversing the properties of specific tissues and cells, however, we find that sex-specific locomotor frequency in C. elegans is determined primarily by the functional modification of shared sensory neurons. Further, we find that sexual modification of body wall muscle together with the nervous system is required to alter body wave speed. Thus, rather than relying on a single focus of modification, sex differences in motor dynamics require independent modifications to multiple tissue types. Our results suggest shared motor behaviors may be sex-specifically optimized though distributed modifications to several aspects of morphology and physiology. PMID:24478342
Astephen Wilson, Janie L; Dunbar, Michael J; Hubley-Kozey, Cheryl L
2015-01-01
The future of total knee arthroplasty (TKA) surgery will involve planning that incorporates more patient-specific characteristics. Despite known biological, morphological, and functional differences between men and women, there has been little investigation into knee joint biomechanical and neuromuscular differences between men and women with osteoarthritis, and none that have examined sex-specific biomechanical and neuromuscular responses to TKA surgery. The objective of this study was to examine sex-associated differences in knee kinematics, kinetics and neuromuscular patterns during gait before and after TKA. Fifty-two patients with end-stage knee OA (28 women, 24 men) underwent gait and neuromuscular analysis within the week prior to and one year after surgery. A number of sex-specific differences were identified which suggest a different manifestation of end-stage knee OA between the sexes. Copyright © 2014 Elsevier Inc. All rights reserved.
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.
Hebert, Karen R; Fales, Jessica; Nangle, Douglas W; Papadakis, Alison A; Grover, Rachel L
2013-11-01
Peer relationships undergo dramatic shifts in form and function during adolescence, at the same time the incidence of socially evaluative fears sharply rises. Despite well-established links between social anxiety and broader interpersonal functioning, there is a dearth of research evaluating the impact of social anxiety on functioning in close relationships during this developmental stage. The present study examines the impact of social anxiety on functioning in close friendships and romantic relationships during adolescence. From a developmental psychopathology perspective, it was expected that social anxiety would influence functioning (quality, length, satisfaction) in romantic relationships through its influence on functioning in same- and other-sex friendships. Participants included 314 adolescents (60.5% female, 14-19 years of age) with a prior or current history of romantic relationship involvement. Structural equation modeling was used to test a mediation model positing an indirect pathway from social anxiety to romantic relationship functioning through functioning in close same- and other-sex friendships. Given known gender differences in social anxiety and relationship functioning, gender also was explored as a potential moderator. Results supported the hypothesized indirect pathway whereby social anxiety was associated with impairment in same-sex friendships; functioning in same-sex friendships was associated with functioning in other-sex friendships, which was associated, in turn, with functioning in romantic relationships. While the hypothesized indirect pathway was significant among both boys and girls, there was greater continuity of functioning between same- and other-sex friendships for girls. These findings highlight the importance of examining the multiple downstream effects of social anxiety on perceived social functioning in adolescence, and suggest that continuity may exist for maladaptive patterns of socialization, particularly across developmentally salient close relationships.
Barnett, Melissa A.; Scaramella, Laura V.
2014-01-01
Sex differences in rates of behavior problems, including internalizing and externalizing problems, begin to emerge during early childhood. These sex differences may occur because mothers parent their sons and daughters differently, or because the impact of parenting on behavior problems is different for boys and girls. This study examines whether associations between observations of mothers’ positive and negative parenting and children’s externalizing and internalizing behaviors vary as a function of child sex. The sample consists of 137 African American, low-income families with one sibling approximately two-years-old and the closest aged older sibling who is approximately four-years-old. Results from fixed-effects within-family models indicate clear sex differences regardless of child age. Mothers were observed to use less positive parenting with sons than with daughters. Higher levels of observed negative parenting were linked to more externalizing behaviors for boys, while lower levels of positive parenting were linked to more externalizing behaviors for girls. No child sex differences emerged regarding associations between observed positive and negative parenting and internalizing behaviors. PMID:23937420
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
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.
Differences in Cognitive Function between Women and Men with HIV.
Maki, Pauline M; Rubin, Leah H; Springer, Gayle; Seaberg, Eric C; Sacktor, Ned; Miller, Eric N; Valcour, Victor; Young, Mary A; Becker, James T; Martin, Eileen M
2018-05-25
Women may be more vulnerable than men to HIV-related cognitive dysfunction due to sociodemographic, lifestyle, mental health, and biological factors. However, studies to date have yielded inconsistent findings on the existence, magnitude and pattern of sex differences. We examined these issues using longitudinal data from two large, prospective, multisite, observational studies of U.S. women and men with and without HIV. Women's Interagency HIV Study (WIHS) and Multicenter AIDS Cohort Study (MACS). HIV-infected (HIV+) and uninfected (HIV-) WIHS and MACS participants completed tests of psychomotor speed, executive function, and fine motor skills. Groups were matched on HIV status, sex, age, education, and black race. Generalized linear mixed models were used to examine group differences on continuous and categorical demographically-corrected T-scores. Results were adjusted for other confounding factors. The sample (n=1420) included 710 women (429 HIV+) and 710 men (429 HIV+) (67% NonHispanic-Black; 53% high school or less). For continuous T-scores, Sex by HIV Serostatus interactions were observed on the Trail Making Test (TMT) Parts A&B, Grooved Pegboard, and Symbol Digit Modalities Test. For these tests, HIV+ women scored lower than HIV+ men, with no sex differences in HIV- individuals. In analyses of categorical scores, particularly TMT Part A and Grooved Pegboard Non-Dominant, HIV+ women also had a higher odds of impairment compared to HIV+ men. Sex differences were constant over time. Although sex differences are generally under-studied, HIV+ women versus men show cognitive disadvantages. Elucidating the mechanisms underlying these differences is critical for tailoring cognitive interventions.
Swift, Andrew J; Capener, Dave; Hammerton, Charlotte; Thomas, Steven M; Elliot, Charlie; Condliffe, Robin; Wild, Jim M; Kiely, David G
2015-01-01
Sex differences exist in both the prevalence and survival of patients with idiopathic pulmonary arterial hypertension (IPAH). Men are less frequently affected by the condition but have worse outcome as compared to females. We sought to characterise the sex related differences in right ventricular remodelling in age matched male and female patients with IPAH using cardiac magnetic resonance imaging (MRI). A case controlled pair-matched study was conducted with patients matched by age and sex. Steady state free precession (SSFP) MRI of the heart was performed at 1.5T. Cardiac volume, function and mass measurements were corrected for age, sex and BSA according to reference data. 40 age and sex matched patients with IPAH were identified. The mean age was 57 (SD 17) in both male and female cohorts. Men had proportionally lower right ventricular (RV) ejection fraction, RV stroke volume and LV stroke volume than females, p=0.028, p=0.007 and p=0.013, respectively. However, there was no significant difference in RV mass or haemodynamic indices of mPAP and PVR between males and females. Male patients with IPAH have proportionally worse RV function despite similar afterload. We hypothesise that adaptive remodelling of the RV in response to increased afterload in IPAH is more effective in females.
Swift, Andrew J.; Capener, Dave; Hammerton, Charlotte; Thomas, Steven M.; Elliot, Charlie; Condliffe, Robin; Wild, Jim M.; Kiely, David G.
2015-01-01
Purpose Sex differences exist in both the prevalence and survival of patients with idiopathic pulmonary arterial hypertension (IPAH). Men are less frequently affected by the condition but have worse outcome as compared to females. We sought to characterise the sex related differences in right ventricular remodelling in age matched male and female patients with IPAH using cardiac magnetic resonance imaging (MRI). Methods A case controlled pair-matched study was conducted with patients matched by age and sex. Steady state free precession (SSFP) MRI of the heart was performed at 1.5T. Cardiac volume, function and mass measurements were corrected for age, sex and BSA according to reference data. Results 40 age and sex matched patients with IPAH were identified. The mean age was 57 (SD 17) in both male and female cohorts. Men had proportionally lower right ventricular (RV) ejection fraction, RV stroke volume and LV stroke volume than females, p=0.028, p=0.007 and p=0.013, respectively. However, there was no significant difference in RV mass or haemodynamic indices of mPAP and PVR between males and females. Conclusion Male patients with IPAH have proportionally worse RV function despite similar afterload. We hypothesise that adaptive remodelling of the RV in response to increased afterload in IPAH is more effective in females. PMID:25996939
Genetic Mechanisms Leading to Sex Differences Across Common Diseases and Anthropometric Traits.
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
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
Genetic regulation of sex differences in songbirds and lizards.
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
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
A predictive relationship between population and genetic sex ratios in clonal species
NASA Astrophysics Data System (ADS)
McLetchie, D. Nicholas; García-Ramos, Gisela
2017-04-01
Sexual reproduction depends on mate availability that is reflected by local sex ratios. In species where both sexes can clonally expand, the population sex ratio describes the proportion of males, including clonally derived individuals (ramets) in addition to sexually produced individuals (genets). In contrast to population sex ratio that accounts for the overall abundance of the sexes, the genetic sex ratio reflects the relative abundance of genetically unique mates, which is critical in predicting effective population size but is difficult to estimate in the field. While an intuitive positive relationship between population (ramet) sex ratio and genetic (genet) sex ratio is expected, an explicit relationship is unknown. In this study, we determined a mathematical expression in the form of a hyperbola that encompasses a linear to a nonlinear positive relationship between ramet and genet sex ratios. As expected when both sexes clonally have equal number of ramets per genet both sex ratios are identical, and thus ramet sex ratio becomes a linear function of genet sex ratio. Conversely, if sex differences in ramet number occur, this mathematical relationship becomes nonlinear and a discrepancy between the sex ratios amplifies from extreme sex ratios values towards intermediate values. We evaluated our predictions with empirical data that simultaneously quantified ramet and genet sex ratios in populations of several species. We found that the data support the predicted positive nonlinear relationship, indicating sex differences in ramet number across populations. However, some data may also fit the null model, which suggests that sex differences in ramet number were not extensive, or the number of populations was too small to capture the curvature of the nonlinear relationship. Data with lack of fit suggest the presence of factors capable of weakening the positive relationship between the sex ratios. Advantages of this model include predicting genet sex ratio using population sex ratios given known sex differences in ramet number, and detecting sex differences in ramet number among populations.
Sex Differences and Brain Development: A Bibliography.
ERIC Educational Resources Information Center
Motomatsu, Nancy; Patterson, Bobbie
This bibliography cites references dealing with background material on the functions of the human brain and current research on sex differences in brain development. A list of 10 books published since 1974 is followed by a more extensive annotated bibliography of 29 articles, and a bibliography of 19 reports, complete with ERIC reference numbers…
ERIC Educational Resources Information Center
Hall, Janie L.; Frederickson, William A.
1979-01-01
The Hall Sex Role Stereotyping Test (HSRST) was used to explore male attitudes toward specified tasks which have traditionally been assigned to either males or females and to determine if men of different ages and educational backgrounds hold different views toward these tasks. (Author/EB)
The role of sex and gender in neuropsychiatric disorders.
Thibaut, Florence
2016-12-01
The prevalence, age of onset, and clinical symptoms of many neuropsychiatric diseases substantially differ between males and females. Factors influencing the relationships between brain development and function and sex or gender may help us understand the differences between males and females in terms of risk or resilience factors in brain diseases.
Fond, G; Boyer, L; Leboyer, M; Godin, O; Llorca, P M; Andrianarisoa, M; Berna, F; Brunel, L; Aouizerate, B; Capdevielle, D; Chereau, I; D'Amato, T; Dubertret, C; Dubreucq, J; Faget, C; Gabayet, F; Mallet, J; Misdrahi, D; Rey, R; Lancon, C; Passerieux, C; Roux, P; Vidailhet, P; Yazbek, H; Schürhoff, F; Bulzacka, E
2018-05-01
Sex differences can yield important clues regarding illness pathophysiology and its treatment. Schizophrenia (SZ) has a lower incidence rate, and a better prognosis, in women versus men. The present study investigated the cognitive profiles of both sexes in a large multi-centre sample of community-dwelling SZ patients. 544 community-dwelling stable SZ subjects (141 women and 403 men; mean age 34.5±12.1 and 31.6±8.7years, respectively) were tested with a comprehensive battery of neuropsychological tests. Although community-dwelling SZ men had more risk factors for impaired cognition (including first-generation antipsychotics administration and comorbid addictive disorders), women had lower scores on a wide range of cognitive functions, including current and premorbid intellectual functioning, working memory, semantic memory, non-verbal abstract thinking and aspects of visual exploration. However, women scored higher in tests of processing speed and verbal learning, as well as having a lower verbal learning bias. No sex difference were evident for visuospatial learning abilities, cued verbal recall, sustained attention and tests of executive functions, including cognitive flexibility, verbal abstract thinking, verbal fluency and planning abilities. Sex differences are evident in the cognitive profiles of SZ patients. The impact on daily functioning and prognosis, as well as longitudinal trajectory, should be further investigated in the FACE-SZ follow-up study. Sex differences in cognition have implications for precision-medicine determined therapeutic strategies. Given the restricted age range of the sample, future research will have to determine cognitive profiles across gender in late onset SZ. Copyright © 2017 Elsevier B.V. All rights reserved.
Gur, Raquel E; Gur, Ruben C
2016-11-01
Sex differences in brain and behavior were investigated across the lifespan. Parameters include neurobehavioral measures linkable to neuroanatomic and neurophysiologic indicators of brain structure and function. Sexual differentiation of behavior has been related to organizational factors during sensitive periods of development, with adolescence and puberty gaining increased attention. Adolescence is a critical developmental period where transition to adulthood is impacted by multiple factors that can enhance vulnerability to brain dysfunction. Here we highlight sex differences in neurobehavioral measures in adolescence that are linked to brain function. We summarize neuroimaging studies examining brain structure, connectivity and perfusion, underscoring the relationship to sex differences in behavioral measures and commenting on hormonal findings. We focus on relevant data from the Philadelphia Neurodevelopmental Cohort (PNC), a community-based sample of nearly 10,000 clinically and neurocognitively phenotyped youths age 8-21 of whom 1600 have received multimodal neuroimaging. These data indicate early and pervasive sexual differentiation in neurocognitive measures that is linkable to brain parameters. We conclude by describing possible clinical implications. Copyright © 2016 Elsevier Ltd. All rights reserved.
Sex differences in spatiotemporal expression of AR, ERα, and ERβ mRNA in the perinatal mouse brain.
Mogi, Kazutaka; Takanashi, Haruka; Nagasawa, Miho; Kikusui, Takefumi
2015-01-01
It has been shown that every masculinized function might be organized by a particular contribution of androgens vs. estrogens in a critical time window. Here, we aimed to investigate the sex differences in brain testosterone levels and in the spatiotemporal dynamics of steroid receptor mRNA expression in perinatal mice, by using enzyme immunoassay and real-time PCR, respectively. We found that testosterone levels in the forebrain transiently increased around birth in male mice. During the perinatal period, levels of androgen receptor mRNA in the hypothalamus (hypo) and prefrontal cortex (PFC) were higher in male mice than in female mice. Estrogen receptor α (ERα) mRNA levels in the hypo and hippocampus were higher in male mice than in female mice before birth. In contrast, ERβ mRNA expression in the PFC was higher in female mice immediately after birth. These spatiotemporal sex differences in steroid receptor expression might contribute to organizing sex differences of not only reproductive function, but also anxiety, stress responses, and cognition in mice. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
Gur, Raquel E.; Gur, Ruben C.
2016-01-01
Sex differences in brain and behavior were investigated across the lifespan. Parameters include neurobehavioral measures linkable to neuroanatomic and neurophysiologic indicators of brain structure and function. Sexual differentiation of behavior has been related to organizational factors during sensitive periods of development, with adolescence and puberty gaining increased attention. Adolescence is a critical developmental period where transition to adulthood is impacted by multiple factors that can enhance vulnerability to brain dysfunction. Here we highlight sex differences in neurobehavioral measures in adolescence that are linked to brain function. We summarize neuroimaging studies examining brain structure, connectivity and perfusion, underscoring the relationship to sex differences in behavioral measures and commenting on hormonal findings. We focus on relevant data from the Philadelphia Neurodevelopmental Cohort (PNC), a community-based sample of nearly 10,000 clinically and neurocognitively phenotyped youths age 8–21 of whom 1600 have received multimodal neuroimaging. These data indicate early and pervasive sexual differentiation in neurocognitive measures that is linkable to brain parameters. We conclude by describing possible clinical implications. PMID:27498084
Rice, Nathaniel C; Makar, Jennifer R; Myers, Todd M
2017-03-15
The stimulus-movement effect refers to the phenomenon in which stimulus discrimination or acquisition of a response is facilitated by moving stimuli as opposed to stationary stimuli. The effect has been found in monkeys, rats, and humans, but the experiments conducted did not provide adequate female representation to investigate potential sex differences. The current experiment analyzed acquisition of stimulus touching in a progressive series of classical conditioning procedures in cynomolgus monkeys (Macaca fascicularis) as a function of sex and stimulus movement. Classical conditioning tasks arrange two or more stimuli in relation to each other with different temporal and predictive relations. Autoshaping procedures overlay operant contingencies onto a classical-conditioning stimulus arrangement. In the present case, a neutral stimulus (a small gray square displayed on a touchscreen) functioned as the conditional stimulus and a food pellet functioned as the unconditional stimulus. Although touching is not required to produce food, with repeated stimulus pairings subjects eventually touch the stimulus. Across conditions of increasing stimulus correlation and temporal contiguity, male monkeys acquired the response faster with a moving stimulus. In contrast, females acquired the response faster with a stationary stimulus. These results demonstrate that the stimulus-movement effect may be differentially affected by sex and indicate that additional experiments with females are needed to determine how sex interacts with behavioral phenomena discovered and elaborated almost exclusively using males. Published by Elsevier Inc.
Gur, Ruben C; Gur, Raquel E
2017-01-02
Although, overwhelmingly, behavior is similar in males and females, and, correspondingly, the brains are similar, sex differences permeate both brain and behavioral measures, and these differences have been the focus of increasing scrutiny by neuroscientists. This Review describes milestones from more than 3 decades of research in brain and behavior. This research was necessarily bound by available methodology, and we began with indirect behavioral indicators of brain function such as handedness. We proceeded to the use of neuropsychological batteries and then to structural and functional neuroimaging that provided the foundations of a cognitive neuroscience-based computerized neurocognitive battery. Sex differences were apparent and consistent in neurocognitive measures, with females performing better on memory and social cognition tasks and males on spatial processing and motor speed. Sex differences were also prominent in all major brain parameters, including higher rates of cerebral blood flow, higher percentage of gray matter tissue, and higher interhemispheric connectivity in females, compared with higher percentage of white matter and greater intrahemispheric connectivity as well as higher glucose metabolism in limbic regions in males. Many of these differences are present in childhood, but they become more prominent with adolescence, perhaps linked to puberty. Overall, they indicate complementarity between the sexes that would result in greater adaptive diversity. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Sex differences in episodic memory in early midlife: impact of reproductive aging.
Rentz, Dorene M; Weiss, Blair K; Jacobs, Emily G; Cherkerzian, Sara; Klibanski, Anne; Remington, Anne; Aizley, Harlyn; Goldstein, Jill M
2017-04-01
Few have characterized cognitive changes with age as a function of menopausal stage relative to men, or sex differences in components of memory in early midlife. The study aim was to investigate variation in memory function in early midlife as a function of sex, sex steroid hormones, and reproductive status. A total of 212 men and women aged 45 to 55 were selected for this cross-sectional study from a prenatal cohort of pregnancies whose mothers were originally recruited in 1959 to 1966. They underwent clinical and cognitive testing and hormonal assessments of menopause status. Multivariate general linear models for multiple memory outcomes were used to test hypotheses controlling for potential confounders. Episodic memory, executive function, semantic processing, and estimated verbal intelligence were assessed. Associative memory and episodic verbal memory were assessed using Face-Name Associative Memory Exam (FNAME) and Selective Reminding Test (SRT), given increased sensitivity to detecting early cognitive decline. Impacts of sex and reproductive stage on performance were tested. Women outperformed men on all memory measures including FNAME (β = -0.30, P < 0.0001) and SRT (β = -0.29, P < 0.0001). Furthermore, premenopausal and perimenopausal women outperformed postmenopausal women on FNAME (initial learning, β= 0.32, P = 0.01) and SRT (recall, β= 2.39, P = 0.02). Across all women, higher estradiol was associated with better SRT performance (recall, β = 1.96, P = 0.01) and marginally associated with FNAME (initial learning, β = 0.19, P = 0.06). This study demonstrated that, in early midlife, women outperformed age-matched men across all memory measures, but sex differences were attenuated for postmenopausal women. Initial learning and memory retrieval were particularly vulnerable, whereas memory consolidation and storage were preserved. Findings underscore the significance of the decline in ovarian estradiol production in midlife and its role in shaping memory function.
Amorim, Mayra Z; Machado, Marco; Hackney, Anthony C; de Oliveira, Wilkes; Luz, Carla Patrícia Novais; Pereira, Rafael
2014-01-01
We investigated differences in sex responses in serum CK activity and renal function measured by glomerular filtration rate (GFR) after an exercise session. Twenty-two healthy and trained volunteers (11 males and 11 females) performed 17 resistance exercises with 3 × 12 repetitions in a circuit training fashion. Subjects provided blood samples prior to exercise session, and at 24, 48, and 72 h following exercise sessions for creatine kinase and creatinine. Twenty-four-hour urine samples were collected before and 72 h after the exercise. Estimate (e) GFR was obtained by using the Chronic Kidney Disease Epidemiology Collaboration equation adjusted for males and females. After the exercise session, males showed greater serum CK activity than females (p < 0.02), serum creatinine increased 31.3 % for males and 29.8 % for females, and urinary creatinine decreased on average 5.4 % for males and 0.6 % for females, with no significant differences (p > 0.05) between sex for serum and urinary creatinine. eGFR decreased significantly for males (~10 %) and females (~8 %), but also without a difference between the sexes (p > 0.05). The correlation between CK and eGFR was significant for males (r = -0.794; p = 0.003), and females (r = -0.8875; p < 0.001). A significant negative correlation between CK activity and the eGFR indice of renal function in both males and females was observed. Additionally, the renal function compromise was similar for both sexes, despite males presenting greater exercise-induced skeletal muscle damage when compared to females.
RAS and sex differences in diabetic nephropathy.
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.
Côté, Julie N
2012-01-01
The objective of this paper is to critically review recent literature on physical and functional sex/gender (s/g) differences, with focus on physical determinants associated with neck/shoulder musculoskeletal injuries. It is well known that there are s/g differences in anthropometrical and functional body characteristics (e.g. size and strength). However, s/g differences may be wrongly attributed if data analysis does not include appropriate corrections (e.g. by strength for endurance). Recent literature on motor control shows that there may indeed be s/g differences in muscle coordination and movement strategies during upper limb tasks that are not currently explained by methodological inadequacies. Moreover, recent studies have shown differences between men and women in sensory hypersensitivity characteristics associated with neck/shoulder injuries. Taken together, the literature points to the importance of accounting for possible s/g differences at all levels of the biopsychosocial system in order to better understand sex- and gender-specific issues relevant to workplace health. This article critically reviews recent literature and a conceptual model highlighting s/g differences in physical and functional characteristics related to neck/shoulder musculoskeletal disorders (NSMSD). Findings have implications on understanding how personal factors may affect NSMSD risk. With better understanding, practitioners can make more appropriate decisions to prevent work-related NSMSD.
Perils and pitfalls of reporting sex differences
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 hormones adjust "sex-specific" reactive and diurnal cortisol profiles.
Juster, Robert-Paul; Raymond, Catherine; Desrochers, Alexandra Bisson; Bourdon, Olivier; Durand, Nadia; Wan, Nathalie; Pruessner, Jens C; Lupien, Sonia J
2016-01-01
Sex differences in stress hormone functions are presumed to depend on sex hormones. And yet, surprisingly few psychoneuroendocrine studies actually assess within-sex variations of testosterone, estradiol, and progesterone when investigating sex-specific activities of the hypothalamic-pituitary-adrenal axis. In this methodological study of 204 healthy adults (60 men), we assessed whether cortisol profiles would differ between the sexes when unadjusted or adjusted for basal sex hormones among both sexes. Reactive cortisol was sampled using 6 saliva samples measured every 10-min as part of the Trier Social Stress Test that generally activates cortisol among men more than women. Diurnal cortisol was sampled over two days at (1) awakening, (2) 30-min thereafter, (3) 1400 h, (4) 1600 h, and (5) bedtime. Sex hormones were collected at baseline before the psychosocial stressor and on two occasions during diurnal cortisol assessment. Repeated-measures analysis of covariance controlled for key covariates in analyses unadjusted or adjusted for sex hormones. Results revealed that men had higher reactive cortisol than women in unadjusted analysis, but this sex difference was attenuated when adjusting for sex hormones. While diurnal cortisol showed no sex differences in unadjusted models, adjusting for sex hormones revealed that women have higher morning cortisol. Correlations using area under the curve formulae revealed intriguing sex-specific associations with progesterone in men and testosterone in women that we propose have implications for social and affective neuroscience. In summary, our results reveal that adjusting for sex hormones alters "sex-specific" reactive and diurnal cortisol profiles. Copyright © 2015 Elsevier Ltd. All rights reserved.
Ruppert, Mihály; Korkmaz-Icöz, Sevil; Loganathan, Sivakkanan; Jiang, Weipeng; Lehmann, Lorenz H; Oláh, Attila; Sayour, Alex Ali; Barta, Bálint András; Merkely, Béla; Karck, Matthias; Radovits, Tamás; Szabó, Gábor
2018-05-25
Sex differences in pressure overload (PO)-induced left ventricular (LV) myocardial hypertrophy (LVH) have been intensely investigated. Nevertheless, sex-related disparities of LV hemodynamics in LVH were not examined in detail. Therefore, we aimed to provide a detailed characterization of distinct aspects of LV function in male and female rats during different stages of LVH. Banding of the abdominal aorta (AB) was performed to induce PO for 6 or 12 weeks in male and female rats. Control animals underwent sham operation. The development of LVH was followed by serial echocardiography. Cardiac function was assessed by pressure-volume analysis. Cardiomyocyte hypertrophy and fibrosis were evaluated by histology. At week 6, increased LV mass index, heart weight-to-tibial length, cardiomyocyte diameter, concentric LV geometry and moderate interstitial fibrosis were detected in both male and female AB rats, indicating the development of an early stage of LVH. Functionally, at this time point, impaired active relaxation, increased contractility and preserved ventricular-arterial coupling were observed in the AB groups in both genders. In contrast, at week 12, progressive deterioration of LVH-associated structural and functional alterations occurred in male but not in female animals with sustained PO. Accordingly, at this later stage, LVH was associated with eccentric remodeling, exacerbated fibrosis and increased chamber stiffness in male AB rats. Furthermore, augmented contractility declined in male and not in female AB animals, resulting in contractility-afterload mismatch. Maintained contractility augmentation, preserved ventricular-arterial coupling and better myocardial compliance in female rats contribute to sex differences in LV function during the progression of PO-induced LVH.
Sex Differences in Patient-Reported Poststroke Disability.
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.
Chang, Ling-Yin; Wu, Chi-Chen; Lin, Linen Nymphas; Yen, Lee-Lan; Chang, Hsing-Yi
2016-07-01
To examine the longitudinal relationship between sleep problems and development of antisocial behavior from adolescence through young adulthood, and to investigate whether family functioning moderates the association being examined. Potential sex differences were also explored. A total of 2,491 adolescents participated in a prospective study spanning 2009 through 2014 in northern Taiwan. Measures included sleep problems, family functioning (parental support, family interaction, and family conflict), antisocial behavior, and other individual characteristics (sex, age, parental education, family economic stress, depressive symptoms, and stressful life events). Random coefficient growth models were used to test study hypotheses. Sleep problems were significantly and positively associated with antisocial behavior (B = 0.088 and 0.038 for males and females, respectively). Sex differences further emerged in the moderating effects of family functioning. Among males, those with high family interaction had a weaker association between sleep problems and antisocial behavior; among females, the examined association was weaker in those with high parental support. For both sexes, the association between sleep problems and antisocial behavior was stronger for those with high family conflict. Our findings highlight the robust link between sleep problems and adolescent antisocial behavior over time. We also show for the first time that the association depends on family functioning. Prevention methods and treatment of sleep problems in youths that incorporate family functioning may yield significant benefits for decreasing antisocial behavior. Sex-specific intervention and prevention approaches should also be considered. © 2016 Associated Professional Sleep Societies, LLC.
Sex differences in spatial ability: a lateralization of function approach.
Rilea, Stacy L; Roskos-Ewoldsen, Beverly; Boles, David
2004-12-01
The current study was designed to examine whether the extent of the male advantage in performance on a spatial task was determined by the extent to which the task was right-hemisphere dependent. Participants included 108 right-handed men and women who completed the mental rotation, waterlevel, and paperfolding tasks, all of which were presented bilaterally. The results partially supported the hypothesis. On the mental rotation task, men showed a right-hemisphere advantage, whereas women showed no hemispheric differences; however, no overall sex differences were observed. On the waterlevel task, men outperformed women, and both men and women showed a right-hemisphere advantage. On the paperfolding task, no sex or hemispheric differences were observed. Although the findings of the current study were mixed, the study provides a framework for examining sex differences across different types of spatial ability.
Sex differences in oxidative stress resistance in relation to longevity in Drosophila melanogaster.
Niveditha, S; Deepashree, S; Ramesh, S R; Shivanandappa, T
2017-10-01
Gender differences in lifespan and aging are known across species. Sex differences in longevity within a species can be useful to understand sex-specific aging. Drosophila melanogaster is a good model to study the problem of sex differences in longevity since females are longer lived than males. There is evidence that stress resistance influences longevity. The objective of this study was to investigate if there is a relationship between sex differences in longevity and oxidative stress resistance in D. melanogaster. We observed a progressive age-dependent decrease in the activity of SOD and catalase, major antioxidant enzymes involved in defense mechanisms against oxidative stress in parallel to the increased ROS levels over time. Longer-lived females showed lower ROS levels and higher antioxidant enzymes than males as a function of age. Using ethanol as a stressor, we have shown differential susceptibility of the sexes to ethanol wherein females exhibited higher resistance to ethanol-induced mortality and locomotor behavior compared to males. Our results show strong correlation between sex differences in oxidative stress resistance, antioxidant defenses and longevity. The study suggests that higher antioxidant defenses in females may confer resistance to oxidative stress, which could be a factor that influences sex-specific aging in D. melanogaster.
[Pain medicine from intercultural and gender-related perspectives].
Schiltenwolf, M; Pogatzki-Zahn, E M
2015-10-01
Cultural setting and sex and gender of the patient are important factors affecting the occurrence, severity, clinical course and prognosis of pain and pain-related diseases. Intercultural differences in the perception and verbal expression of symptoms and emotional function are fundamental and it is important to realize these differences in order to understand patients with a migration background. A trusting doctor-patient relationship is generally very sensitive and it is even more difficult to establish when differences in the cultural background impair mutual understanding. Regarding sex and gender there is evidence that females are more susceptible to developing chronic pain conditions, experience more severe pain and respond differently to pain therapy; however, results of recent studies indicate that females are not that different to males when comparing several modalities of experimental pain (although some differences exist). Similarly, sex and gender differences in postoperative pain seem to exist but the differences are relatively small when pain scores are compared. Other aspects, such as the response to analgesics and role of psychosocial factors should be addressed when sex and gender aspects are studied. Similarly, sex and gender differences in the prevalence of chronic pain exist but the results of some studies, e.g. those controlling for confounders, are not very clear. Research is needed to delineate the role of specific aspects affecting sex and gender differences and the underlying mechanisms (e.g. reduced inhibitory control, hormones, psychological aspects and social factors). Altogether, we need to open our minds to some intercultural and sex and gender aspects in the clinical setting. For sex and gender differences we may need a more biopsychosocial approach to understand the underlying differences and differentiate between sex and gender and sex and gender-associated aspects for acute and chronic pain.
Sex differences in the physiology of eating
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
Sex Differences and Laterality in Astrocyte Number and Complexity in the Adult Rat Medial Amygdala
JOHNSON, RYAN T.; BREEDLOVE, S. MARC; JORDAN, CYNTHIA L.
2008-01-01
The posterodorsal portion of the medial amygdala (MePD) is sexually dimorphic in several rodent species. In several other brain nuclei, astrocytes change morphology in response to steroid hormones. We visualized MePD astrocytes using glial-fibrillary acidic protein (GFAP) immunocytochemistry. We compared the number and process complexity of MePD astrocytes in adult wildtype male and female rats and testicular feminized mutant (TFM) male rats that lack functional androgen receptors (ARs) to determine whether MePD astrocytes are sexually differentiated and whether ARs have a role. Unbiased stereological methods revealed laterality and sex differences in MePD astrocyte number and complexity. The right MePD contained more astrocytes than the left in all three genotypes, and the number of astrocytes was also sexually differentiated in the right MePD, with males having more astrocytes than females. In contrast, the left MePD contained more complex astrocytes than did the right MePD in all three genotypes, and males had more complex astrocytes than females in this hemisphere. TFM males were comparable to wildtype females, having fewer astrocytes on the right and simpler astrocytes on the left than do wildtype males. Taken together, these results demonstrate that astrocytes are sexually dimorphic in the adult MePD and that the nature of the sex difference is hemisphere-dependent: a sex difference in astrocyte number in the right MePD and a sex difference in astrocyte complexity in the left MePD. Moreover, functional ARs appear to be critical in establishing these sex differences in MePD astrocyte morphology. PMID:18853427
Integrative Analysis of Sex-Specific microRNA Networks Following Stress in Mouse Nucleus Accumbens.
Pfau, Madeline L; Purushothaman, Immanuel; Feng, Jian; Golden, Sam A; Aleyasin, Hossein; Lorsch, Zachary S; Cates, Hannah M; Flanigan, Meghan E; Menard, Caroline; Heshmati, Mitra; Wang, Zichen; Ma'ayan, Avi; Shen, Li; Hodes, Georgia E; Russo, Scott J
2016-01-01
Adult women are twice as likely as men to suffer from affective and anxiety disorders, although the mechanisms underlying heightened female stress susceptibility are incompletely understood. Recent findings in mouse Nucleus Accumbens (NAc) suggest a role for DNA methylation-driven sex differences in genome-wide transcriptional profiles. However, the role of another epigenetic process-microRNA (miR) regulation-has yet to be explored. We exposed male and female mice to Subchronic Variable Stress (SCVS), a stress paradigm that produces depression-like behavior in female, but not male, mice, and performed next generation mRNA and miR sequencing on NAc tissue. We applied a combination of differential expression, miR-mRNA network and functional enrichment analyses to characterize the transcriptional and post-transcriptional landscape of sex differences in NAc stress response. We find that male and female mice exhibit largely non-overlapping miR and mRNA profiles following SCVS. The two sexes also show enrichment of different molecular pathways and functions. Collectively, our results suggest that males and females mount fundamentally different transcriptional and post-transcriptional responses to SCVS and engage sex-specific molecular processes following stress. These findings have implications for the pathophysiology and treatment of stress-related disorders in women.
Effects of Sex and Gender on Adaptation to Space: Neurosensory Systems
Cohen, Helen S.; Cerisano, Jody M.; Clayton, Janine A.; Cromwell, Ronita; Danielson, Richard W.; Hwang, Emma Y.; Tingen, Candace; Allen, John R.; Tomko, David L.
2014-01-01
Abstract Sex and gender differences have long been a research topic of interest, yet few studies have explored the specific differences in neurological responses between men and women during and after spaceflight. Knowledge in this field is limited due to the significant disproportion of sexes enrolled in the astronaut corps. Research indicates that general neurological and sensory differences exist between the sexes, such as those in laterality of amygdala activity, sensitivity and discrimination in vision processing, and neuronal cell death (apoptosis) pathways. In spaceflight, sex differences may include a higher incidence of entry and space motion sickness and of post-flight vestibular instability in female as opposed to male astronauts who flew on both short- and long-duration missions. Hearing and auditory function in crewmembers shows the expected hearing threshold differences between men and women, in which female astronauts exhibit better hearing thresholds. Longitudinal observations of hearing thresholds for crewmembers yield normal age-related decrements; however, no evidence of sex-related differences from spaceflight has been observed. The impact of sex and gender differences should be studied by making spaceflight accessible and flying more women into space. Only in this way will we know if increasingly longer-duration missions cause significantly different neurophysiological responses in men and women. PMID:25401941
The influence of sex-linked genetic mechanisms on attention and impulsivity
Trent, Simon; Davies, William
2012-01-01
It is now generally agreed that there are inherent sex differences in healthy individuals across a number of neurobiological domains (including brain structure, neurochemistry, and cognition). Moreover, there is a burgeoning body of evidence highlighting sex differences within neuropsychiatric populations (in terms of the rates of incidence, clinical features/progression, neurobiology and pathology). Here, we consider the extent to which attention and impulsivity are sexually dimorphic in healthy populations and the extent to which sex might modulate the expression of disorders characterised by abnormalities in attention and/or impulsivity such as attention deficit hyperactivity disorder (ADHD), autism and addiction. We then discuss general genetic mechanisms that might underlie sex differences in attention and impulsivity before focussing on specific positional and functional candidate sex-linked genes that are likely to influence these cognitive processes. Identifying novel sex-modulated molecular targets should ultimately enable us to develop more effective therapies in disorders associated with attentional/impulsive dysfunction. PMID:21983394
Sex determination from the talus and calcaneus measurements.
Gualdi-Russo, Emanuela
2007-09-13
Several studies have demonstrated that discriminant function equations used to determine the sex of a skeleton are population-specific. The purpose of the present research was to develop discriminant function equations for sex determination on the basis of 18 variables on the right and left talus and calcaneus in a modern northern Italian sample. The sample consisted of 118 skeletons (62 males and 56 females) from the Frassetto Collection (University of Bologna). The ages of the individuals ranged from 19 to 70 years. The results indicated that metric traits of the talus (in particular) and calcaneus are good indicators of sexual dimorphism. The percentage of correct classification was high (87.9-95.7%). In view of the differences among current Italian populations, we tested the validity of the discriminant function equations in an independent sample of individuals of different origin (northern and southern Italy). The accuracy of classification was high only for the northern Italians. Most southern Italian males were misclassified as females, confirming the population-specificity of discriminant function equations.
A Review and Critique of Research on Same-Sex Parenting and Adoption.
Schumm, Walter R
2016-12-01
Are the outcomes for children of gay, lesbian, or bisexual parents in general the same as those for heterosexual parents? That controversial question is discussed here in a detailed review of the social science literature in three parts: (1) stability of same-sex parental relationships, (2) child outcomes, and (3) child outcomes in same-sex adoption. Relationship instability appears to be higher among gay and lesbian parent couples and may be a key mediating factor influencing outcomes for children. With respect to part 2, while parental self-reports usually present few significant differences, social desirability or self-presentation bias may be a confounding factor. While some researchers have tended to conclude that there are no differences whatsoever in terms of child outcomes as a function of parental sexual orientation, such conclusions appear premature in the light of more recent data in which some different outcomes have been observed in a few studies. Studies conducted within the past 10 years that compared child outcomes for children of same-sex and heterosexual adoptive parents were reviewed. Numerous methodological limitations were identified that make it very difficult to make an accurate assessment of the effect of parental sexual orientation across adoptive families. Because of sampling limitations, we still know very little about family functioning among same-sex adoptive families with low or moderate incomes, those with several children, or those with older children, including adolescents or how family functioning may change over time. There remains a need for high-quality research on same-sex families, especially families with gay fathers and with lower income. © The Author(s) 2016.
Allore, Heather G.; Mendes de Leon, Carlos F.; Gahbauer, Evelyne A.; Gill, Thomas M.
2016-01-01
Background: Despite documented age-related declines in self-reported functional status and measured physical capacity, it is unclear whether these functional indicators follow similar trajectories over time or whether the patterns of change differ by sex. Methods: We used longitudinal data from 687 initially nondisabled adults, aged 70 or older, from the Precipitating Events Project, who were evaluated every 18 months for nearly 14 years. Self-reported disability was assessed with a 12-item disability scale. Physical capacity was measured using grip strength and a modified version of Short Physical Performance Battery. Hierarchical linear models estimated the intra-individual trajectory of each functional indicator and differences in trajectories’ intercept and slope by sex. Results: Self-reported disability, grip strength, and Short Physical Performance Battery score declined over 13.5 years following nonlinear trajectories. Women experienced faster accumulation of self-reported disability, but slower declines in measured physical capacity, compared with men. Trajectory intercepts revealed that women had significantly weaker grip strength and reported higher levels of disability compared with men, with no differences in starting Short Physical Performance Battery scores. These findings were robust to adjustments for differences in sociodemographic characteristics, length-of-survival, health risk factors, and chronic-disease status. Conclusions: Despite the female disadvantage in self-reported disability, older women preserve measured physical capacity better than men over time. Self-reported and measured indicators should be viewed as complementary rather than interchangeable assessments of functional status for both clinical and research purposes, especially for sex-specific comparisons. PMID:27071781
Chang, Ling-Yin; Wu, Chi-Chen; Lin, Linen Nymphas; Yen, Lee-Lan; Chang, Hsing-Yi
2016-01-01
Study Objectives: To examine the longitudinal relationship between sleep problems and development of antisocial behavior from adolescence through young adulthood, and to investigate whether family functioning moderates the association being examined. Potential sex differences were also explored. Methods: A total of 2,491 adolescents participated in a prospective study spanning 2009 through 2014 in northern Taiwan. Measures included sleep problems, family functioning (parental support, family interaction, and family conflict), antisocial behavior, and other individual characteristics (sex, age, parental education, family economic stress, depressive symptoms, and stressful life events). Random coefficient growth models were used to test study hypotheses. Results: Sleep problems were significantly and positively associated with antisocial behavior (B = 0.088 and 0.038 for males and females, respectively). Sex differences further emerged in the moderating effects of family functioning. Among males, those with high family interaction had a weaker association between sleep problems and antisocial behavior; among females, the examined association was weaker in those with high parental support. For both sexes, the association between sleep problems and antisocial behavior was stronger for those with high family conflict. Conclusions: Our findings highlight the robust link between sleep problems and adolescent antisocial behavior over time. We also show for the first time that the association depends on family functioning. Prevention methods and treatment of sleep problems in youths that incorporate family functioning may yield significant benefits for decreasing antisocial behavior. Sex-specific intervention and prevention approaches should also be considered. Citation: Chang LY, Wu CC, Lin LN, Yen LL, Chang HY. The effects of sleep problems on the trajectory of antisocial behavior from adolescence through early adulthood in Taiwan: family functioning as a moderator. SLEEP 2016;39(7):1441–1449. PMID:27166239
Sex differences in the functional lateralization of emotion and decision-making in the human brain
Reber, Justin; Tranel, Daniel
2016-01-01
Dating back to the case of Phineas Gage, decades of neuropsychological research have shown that the ventromedial prefrontal cortex (vmPFC) is crucial to both real-world social functioning and abstract decision-making in the laboratory (e.g., Bechara et al., 1994; Damasio et al., 1994; Stuss et al., 1983). Previous research has found that the relationship between the laterality of individuals’ vmPFC lesions and neuropsychological performance is moderated by their sex, whereby there are more severe social, emotional, and decision-making impairments in men with right-sided vmPFC lesions and in women with left-sided vmPFC lesions (Tranel et al., 2005; Sutterer et al., 2015). We conducted a selective review of studies examining the effect of vmPFC lesions on emotion and decision-making, and found further evidence of sex-related differences in the lateralization of function not only in the vmPFC, but also in other neurological structures associated with decision-making and emotion. Our review suggests that both sex and laterality effects warrant more careful consideration in the scientific literature. PMID:27870462
ERIC Educational Resources Information Center
Wijting, Jan P.; And Others
1978-01-01
Cross-sectional comparison of elementary and secondary school children and parents examined changes in work values and relationships between children's and parents' work values as a function of age and sex. Revealed support for hypothesized differences in children's values and for convergence of sex differences in values at later ages. (Author)
Aw, Wen C.; Garvin, Michael R.; Melvin, Richard G.
2017-01-01
Here we determine the sex-specific influence of mtDNA type (mitotype) and diet on mitochondrial functions and physiology in two Drosophila melanogaster lines. In many species, males and females differ in aspects of their energy production. These sex-specific influences may be caused by differences in evolutionary history and physiological functions. We predicted the influence of mtDNA mutations should be stronger in males than females as a result of the organelle’s maternal mode of inheritance in the majority of metazoans. In contrast, we predicted the influence of diet would be greater in females due to higher metabolic flexibility. We included four diets that differed in their protein: carbohydrate (P:C) ratios as they are the two-major energy-yielding macronutrients in the fly diet. We assayed four mitochondrial function traits (Complex I oxidative phosphorylation, reactive oxygen species production, superoxide dismutase activity, and mtDNA copy number) and four physiological traits (fecundity, longevity, lipid content, and starvation resistance). Traits were assayed at 11 d and 25 d of age. Consistent with predictions we observe that the mitotype influenced males more than females supporting the hypothesis of a sex-specific selective sieve in the mitochondrial genome caused by the maternal inheritance of mitochondria. Also, consistent with predictions, we found that the diet influenced females more than males. PMID:29166659
Tsiligianni, Ioanna; Mezzi, Karen; Fucile, Sebastian; Kostikas, Konstantinos; Shen, Steven; Banerji, Donald; Fogel, Robert
2017-08-01
In this pooled analysis, we compared the effect of indacaterol/glycopyrronium (IND/GLY) by sex versus other commonly used chronic obstructive pulmonary disease (COPD) treatments and placebo. Male and female patients with moderate-to-very-severe COPD who had participated in six randomized controlled trials were included in the analysis. Baseline demographics and disease characteristics were analyzed by sex, and any differences noted. The effects of IND/GLY versus salmeterol/fluticasone (SFC), glycopyrronium, tiotropium and placebo, on lung function and the patient-reported outcomes (health status, dyspnea, rescue medication use and symptoms) were assessed by sex after 26 weeks treatment. The analysis population comprised 4719 men and 1389 women. Most baseline parameters differed significantly between men and women. Nonetheless, despite these differences in baseline characteristics, IND/GLY significantly improved lung function versus placebo (p < 0.0001) and all active comparators (p < 0.01) in men and women. Overall, IND/GLY showed better improvement in dyspnea and health status compared with all other treatments in both sex. Greater reduction of rescue medication use was observed with IND/GLY versus placebo and other treatments (all p < 0.01 expect IND/GLY versus SFC). Although some variability was observed, improvements in health status, dyspnea, rescue medication use and symptoms were generally larger in women than in men. Irrespective of sex, IND/GLY provided superior efficacy to monotherapy or SFC in both men and women. Small differences in efficacy response by sex were observed, which should be evaluated further in prospective clinical studies. Nevertheless, the benefits observed with IND/GLY confirm dual bronchodilator as the preferred therapy in patients with moderate-to-very-severe COPD regardless of sex.
Young women selling sex online – narratives on regulating feelings
Jonsson, Linda S; Svedin, Carl Göran; Hydén, Margareta
2015-01-01
The current study concerns young women’s life stories of their experiences selling sex online before the age of 18. The aim was to gain an understanding of young women’s perceptions of the reasons they started, continued, and stopped selling sex. The study included interviews with 15 young women between the ages of 15 and 25 (M=18.9). Thematic analysis was used to identify similarities and differences in the narratives. Three themes and eight sub-themes were identified in relation to different stages in their lives in the sex trade. The themes were organized into three parts, each with its own storyline: “Entering – adverse life experiences”; traumatic events: feeling different and being excluded. “Immersion – using the body as a tool for regulating feelings”; being seen: being touched: being in control: affect regulation and self-harming. “Exiting – change or die”; living close to death: the process of quitting. The informants all had stable social lives in the sense that they had roofs over their heads, food to eat, and no substance-abuse issues. None had a third party who arranged the sexual contacts and none were currently trafficked. They described how their experiences of traumatic events and of feeling different and excluded had led them into the sex trade. Selling sex functioned as a way to be seen, to handle traumatic events, and to regulate feelings. Professionals working with young people who sell sex online need to understand the complex web of mixed feelings and emotional needs that can play a role in selling sex. Young people selling sex might need guidance in relationship building as well as help processing traumatic experiences and ending self-harming behavior. Further studies are needed on the functions of online sex selling and on the exit process for young people, in order to prevent entrance and facilitate exiting. PMID:25733944
Young women selling sex online - narratives on regulating feelings.
Jonsson, Linda S; Svedin, Carl Göran; Hydén, Margareta
2015-01-01
The current study concerns young women's life stories of their experiences selling sex online before the age of 18. The aim was to gain an understanding of young women's perceptions of the reasons they started, continued, and stopped selling sex. The study included interviews with 15 young women between the ages of 15 and 25 (M=18.9). Thematic analysis was used to identify similarities and differences in the narratives. Three themes and eight sub-themes were identified in relation to different stages in their lives in the sex trade. The themes were organized into three parts, each with its own storyline: "Entering - adverse life experiences"; traumatic events: feeling different and being excluded. "Immersion - using the body as a tool for regulating feelings"; being seen: being touched: being in control: affect regulation and self-harming. "Exiting - change or die"; living close to death: the process of quitting. The informants all had stable social lives in the sense that they had roofs over their heads, food to eat, and no substance-abuse issues. None had a third party who arranged the sexual contacts and none were currently trafficked. They described how their experiences of traumatic events and of feeling different and excluded had led them into the sex trade. Selling sex functioned as a way to be seen, to handle traumatic events, and to regulate feelings. Professionals working with young people who sell sex online need to understand the complex web of mixed feelings and emotional needs that can play a role in selling sex. Young people selling sex might need guidance in relationship building as well as help processing traumatic experiences and ending self-harming behavior. Further studies are needed on the functions of online sex selling and on the exit process for young people, in order to prevent entrance and facilitate exiting.
Sex differences in human epilepsy.
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.
ERIC Educational Resources Information Center
Dean, Michelle Carol
2013-01-01
This dissertation contains two studies, which are intended to expand our current knowledge about girls with ASD without intellectual disability. The first study examined sex-differences in ASD symptom endorsement and coexisting internalizing and externalizing behaviors. The second study explored the social behaviors of boys and girls with ASD at…
Age-Related Sex Differences in Language Lateralization: A Magnetoencephalography Study in Children
ERIC Educational Resources Information Center
Yu, Vickie Y.; MacDonald, Matt J.; Oh, Anna; Hua, Gordon N.; De Nil, Luc F.; Pang, Elizabeth W.
2014-01-01
It is well supported by behavioral and neuroimaging studies that typical language function is lateralized to the left hemisphere in the adult brain and this laterality is less well defined in children. The behavioral literature suggests there maybe be sex differences in language development, but this has not been examined systematically with…
ERIC Educational Resources Information Center
French, Brian F.; Gotch, Chad M.
2013-01-01
The Brigance Comprehensive Inventory of Basic Skills-II (CIBS-II) is a diagnostic battery intended for children in grades 1st through 6th. The aim of this study was to test for item invariance, or differential item functioning (DIF), of the CIBS-II across sex in the standardization sample through the use of item response theory DIF detection…
Sarikouch, Samir; Boethig, Dietmar; Peters, Brigitte; Kropf, Siegfried; Dubowy, Karl-Otto; Lange, Peter; Kuehne, Titus; Haverich, Axel; Beerbaum, Philipp
2013-11-01
In repaired congenital heart disease, there is increasing evidence of sex differences in cardiac remodeling, but there is a lack of comparable data for specific congenital heart defects such as in repaired tetralogy of Fallot. In a prospective multicenter study, a cohort of 272 contemporary patients (158 men; mean age, 14.3±3.3 years [range, 8-20 years]) with repaired tetralogy of Fallot underwent cardiac magnetic resonance for ventricular function and metabolic exercise testing. All data were transformed to standard deviation scores according to the Lambda-Mu-Sigma method by relating individual values to their respective 50th percentile (standard deviation score, 0) in sex-specific healthy control subjects. No sex differences were observed in age at repair, type of repair conducted, or overall hemodynamic results. Relative to sex-specific controls, repaired tetralogy of Fallot in women had larger right ventricular end-systolic volumes (standard deviation scores: women, 4.35; men, 3.25; P=0.001), lower right ventricular ejection fraction (women, -2.83; men, -2.12; P=0.011), lower right ventricular muscle mass (women, 1.58; men 2.45; P=0.001), poorer peak oxygen uptake (women, -1.65; men, -1.14; P<0.001), higher VE/VCO2 (ventilation per unit of carbon dioxide production) slopes (women, 0.88; men 0.58; P=0.012), and reduced peak heart rate (women, -2.16; men -1.74; P=0.017). Left ventricular parameters did not differ between sexes. Relative to their respective sex-specific healthy control subjects, derived standard deviation scores in repaired tetralogy of Fallot suggest that women perform poorer than men in terms of right ventricular systolic function as tested by cardiac magnetic resonance and exercise capacity. This effect cannot be explained by selection bias. Further outcome data are required from longitudinal cohort studies.
Potential Reporting Bias in Neuroimaging Studies of Sex Differences.
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.
Sex and the development of Alzheimer’s disease
Pike, Christian J.
2016-01-01
Men and women exhibit differences in the development and progression of Alzheimer’s disease (AD). The factors underlying the sex differences in AD are not well understood. This review emphasizes the contributions of sex steroid hormones to the relationship between sex and AD. In women, events that decrease lifetime exposure to estrogens are generally associated with increased AD risk, whereas estrogen-based hormone therapy administered near the time of menopause may reduce AD risk. In men, estrogens do not exhibit age-related reduction and are not significantly associated with AD risk. Rather, normal age-related depletions of testosterone in plasma and brain predict enhanced vulnerability to AD. Both estrogens and androgens exert numerous protective actions in the adult brain that increase neural functioning and resilience as well as specifically attenuate multiple aspects of AD-related neuropathology. Aging diminishes the activational effects of sex hormones in sex-specific manners, which is hypothesized to contribute to the relationship between aging and AD. Sex steroid hormones may also drive sex differences in AD through their organizational effects during developmental sexual differentiation of the brain. Specifically, sex hormone actions during early development may confer inherent vulnerability of the female brain to development of AD in advanced age. The combined effects of organizational and activational effects of sex steroids yield distinct sex differences in AD pathogenesis, a significant variable that must be more rigorously considered in future research. PMID:27870425
[Sex and gender: Two different scientific domains to be clarified].
Fernández, Juan
2010-05-01
Nowadays, the word sex and its related terms (sexual differences, sexual roles and stereotypes), so common not long ago, seems to have been replaced by gender and its related terms (gender differences, gender roles and stereotypes). We can sometimes find both sex and gender sharing the same space in scientific articles, although referring to different domains. In this paper, I try to explain the need for a model that can integrate both of these complex domains of sex and gender, leading to two independent, although complementary, disciplines: Sexology and Genderology. In both cases, I start from a functional standpoint, which will give meaning to both disciplines' specificities, as it is meant to link contributions from different fields of knowledge. This approach can have consequences for research, education, the experience of women, men, and ambiguous individuals, and therapy.
Men and women with fibromyalgia: Relation between attentional function and clinical symptoms.
Miró, Elena; Martínez, María P; Sánchez, Ana I; Prados, Germán; Lupiáñez, Juan
2015-09-01
This study was the first to explore whether individuals with fibromyalgia (FM) have different cognitive alterations (i.e., in alertness, orienting, and executive control) depending on their sex. We also analysed possible gender differences in the relationships between cognitive functioning and some of the main symptoms of FM. Cross-sectional study. Two clinical groups with FM (n = 58 women and n = 20 men) and two healthy control groups (n = 21 women and n = 27 men) aged between 30 and 60 years old participated in this study. Pain intensity, sleep disturbance, depression, anxiety, pain catastrophizing, and daily functioning were evaluated with self-report measures. Attentional function was assessed with the ANT-I task (Attentional Network Test-Interactions). Mixed ANOVAs showed impairment in vigilance and executive control in both male and female patients with FM compared with controls. Control men were faster than control women, but FM eliminated sex differences. In addition, attention deficit was associated with worse daily functioning in women but not in men with FM. Emotional distress and sleep disruption seemed to contribute differently to these cognitive alterations in both sexes. Therapy strategies aimed at reducing emotional distress and sleep disruption are likely to improve cognitive function by enhancing vigilance. Therapies aimed at reducing emotional distress seem to improve attentional function more in women than in men; those aimed at improving sleep quality are likely to reduce a vigilance/alertness deficit in women and executive problems in men. © 2014 The British Psychological Society.
Sex hormones and the genesis of autoimmunity.
Ackerman, Lindsay S
2006-03-01
The sexually dimorphic prevalence of autoimmune disease remains one of the most intriguing clinical observations among this group of disorders. While sex hormones have long been recognized for their roles in reproductive functions, within the past 2 decades scientists have found that sex hormones are integral signaling modulators of the mammalian immune system. Sex hormones have definitive roles in lymphocyte maturation, activation, and synthesis of antibodies and cytokines. Sex hormone expression is altered among patients with autoimmune disease, and this variation of expression contributes to immune dysregulation. English-language literature from the last 10 years was reviewed to examine the relationship between sex hormones and the function of the mammalian immune system. Approximately 50 publications were included in this review, and the majority were controlled trials with investigator blinding that compared both male and female diseased and normal subjects. The review provided basic knowledge regarding the broad impact of sex hormones on the immune system and how abnormal sex hormone expression contributes to the development and maintenance of autoimmune phenomena, with a focus on systemic lupus erythematosus, as models of "lupus-prone" mice are readily available. Sex hormones affect the function of the mammalian immune system, and sex hormone expression is different in patients with systemic lupus erythematosus than in healthy subjects. Sex hormones play a role in the genesis of autoimmunity. Future research may provide a therapeutic approach that is capable of altering disease pathogenesis, rather than targeting disease sequelae.
Sources of Sex Education as a Function of Sex, Coital Activity, and Type of Information.
ERIC Educational Resources Information Center
Andre, Thomas; And Others
The perceived importance of sources of sex education and the effects of gender, coital activity, and type of information were studied, and previous studies were assessed. Attention was directed to the relative contribution of parents, institutions, reading, and peers to the information about each of 35 different sexual topics of 116 male and 116…
Genetic dissection of neural circuits underlying sexually dimorphic social behaviours
Bayless, Daniel W.; Shah, Nirao M.
2016-01-01
The unique hormonal, genetic and epigenetic environments of males and females during development and adulthood shape the neural circuitry of the brain. These differences in neural circuitry result in sex-typical displays of social behaviours such as mating and aggression. Like other neural circuits, those underlying sex-typical social behaviours weave through complex brain regions that control a variety of diverse behaviours. For this reason, the functional dissection of neural circuits underlying sex-typical social behaviours has proved to be difficult. However, molecularly discrete neuronal subpopulations can be identified in the heterogeneous brain regions that control sex-typical social behaviours. In addition, the actions of oestrogens and androgens produce sex differences in gene expression within these brain regions, thereby highlighting the neuronal subpopulations most likely to control sexually dimorphic social behaviours. These conditions permit the implementation of innovative genetic approaches that, in mammals, are most highly advanced in the laboratory mouse. Such approaches have greatly advanced our understanding of the functional significance of sexually dimorphic neural circuits in the brain. In this review, we discuss the neural circuitry of sex-typical social behaviours in mice while highlighting the genetic technical innovations that have advanced the field. PMID:26833830
Sex in public and private settings among Latino MSM
Reisen, Carol A; Iracheta, Miguel A.; Zea, Maria Cecilia; Bianchi, Fernanda T.; Poppen, Paul J.
2009-01-01
Latino men who have sex with men (MSM) constitute a group at high risk for HIV. Recent approaches to understanding sexual risk have emphasized the role that contextual factors can play in shaping behavior. This study examined sexual behavior of Latino MSM in private and public settings. First, a within-person comparison of behaviors performed in sexual encounters that occurred in public and private settings was conducted. Unprotected anal intercourse and other sexual behaviors involving anal stimulation were more common in private settings; group sex was more likely in public settings. Second, a between-person analysis compared sexual behaviors of MSM who went to three different types of public sex settings during the previous six months. The types were: 1) commercial sex venues (CSVs), which were defined as businesses with the function of providing a space where MSM can go to have sexual encounters, such as gay bathhouses; 2) commercial sex environments (CSEs), which were defined as businesses with another apparent function, but in which MSM sometimes have sexual encounters, such as gay bars or pornographic movie houses; and 3) public sex environments (PSEs), which were defined as free public areas where MSM can go to find partners for anonymous sex, such as parks or public restrooms. Results indicated that anal sexual behavior was most likely to occur in CSVs and least likely in PSEs, but the probability of unprotected anal intercourse was not found to differ among the three types of settings. Behavioral differences were discussed in terms of structural conditions related to privacy and safety, and psychological factors related to intimacy. PMID:20461575
Sex, stress, and mood disorders: at the intersection of adrenal and gonadal hormones.
Fernández-Guasti, A; Fiedler, J L; Herrera, L; Handa, R J
2012-07-01
The risk for neuropsychiatric illnesses has a strong sex bias, and for major depressive disorder (MDD), females show a more than 2-fold greater risk compared to males. Such mood disorders are commonly associated with a dysregulation of the hypothalamo-pituitary-adrenal (HPA) axis. Thus, sex differences in the incidence of MDD may be related with the levels of gonadal steroid hormone in adulthood or during early development as well as with the sex differences in HPA axis function. In rodents, organizational and activational effects of gonadal steroid hormones have been described for the regulation of HPA axis function and, if consistent with humans, this may underlie the increased risk of mood disorders in women. Other developmental factors, such as prenatal stress and prenatal overexposure to glucocorticoids can also impact behaviors and neuroendocrine responses to stress in adulthood and these effects are also reported to occur with sex differences. Similarly, in humans, the clinical benefits of antidepressants are associated with the normalization of the dysregulated HPA axis, and genetic polymorphisms have been found in some genes involved in controlling the stress response. This review examines some potential factors contributing to the sex difference in the risk of affective disorders with a focus on adrenal and gonadal hormones as potential modulators. Genetic and environmental factors that contribute to individual risk for affective disorders are also described. Ultimately, future treatment strategies for depression should consider all of these biological elements in their design. © Georg Thieme Verlag KG Stuttgart · New York.
Comparison of hormone and electrolyte circadian rhythms in male and female humans
NASA Technical Reports Server (NTRS)
Vernikos-Danellis, J.; Winget, C. M.; Goodwin, A. E.; Reilly, T.
1977-01-01
Circadian rhythm characteristics in healthy male and female humans were studied at 4-hour intervals for urine volume, cortisol, 5-hydroxyindoleacetic acid (5-HIAA), Na, K, Na/K ratios in the urine, as well as plasma cortisol. While plasma and urinary cortisol rhythms were very similar in both sexes, the described rhythms in urine volume, electrolyte, and 5-HIAA excretion differ for the two sexes. The results suggest that sex differences exist in the circadian patterns of important hormone and metabolic functions and that the internal synchrony of circadian rhythms differs for the two sexes. The results seem to indicate that the rhythmical secretion of cortisol does not account for the pattern of Na and K excretion.
Effects of sex and COMT genotype on environmentally modulated cognitive control in mice
Papaleo, Francesco; Erickson, Lucy; Liu, Guangping; Chen, Jingshan; Weinberger, Daniel R.
2012-01-01
Cognitive functioning differs between males and females, likely in part related to genetic dimorphisms. An example of a common genetic variation reported to have sexually dimorphic effects on cognition and temperament in humans is the Val/Met polymorphism in catechol-O-methyltransferase (COMT). We tested male and female wild-type mice (+/+) and their COMT knockout littermates (+/− and −/−) in the five-choice serial reaction time task (5CSRTT) to investigate the effects of sex, COMT genotype, and their interactions with environmental manipulations of cognitive functions such as attention, impulsivity, compulsivity, motivation, and rule-reversal learning. No sex- or COMT-dependent differences were present in the basic acquisition of the five-choice serial reaction time task. In contrast, specific environmental manipulations revealed a variety of sex- and COMT-dependent effects. Following an experimental change to trigger impulsive responding, the sexes showed similar increases in impulsiveness, but males eventually habituated whereas females did not. Moreover, COMT knockout mice were more impulsive compared with wild-type littermates. Manipulations involving mild stress adversely affected cognitive performance in males, and particularly COMT knockout males, but not in females. In contrast, following amphetamine treatment, subtle sex by genotype and sex by treatment interactions emerged primarily limited to compulsive behavior. After repeated testing, female mice showed improved performance, working harder and eventually outperforming males. Finally, removing the food-restriction condition enhanced sex and COMT differences, revealing that overall, females outperform males and COMT knockout males outperform their wild-type littermates. These findings illuminate complex sex- and COMT-related effects and their interactions with environmental factors to influence specific executive cognitive domains. PMID:23169629
Sex bias in paediatric autoimmune disease - Not just about sex hormones?
Chiaroni-Clarke, Rachel C; Munro, Jane E; Ellis, Justine A
2016-05-01
Autoimmune diseases affect up to 10% of the world's population, and approximately 80% of those affected are female. The majority of autoimmune diseases occur more commonly in females, although some are more frequent in males, while others show no bias by sex. The mechanisms leading to sex biased disease prevalence are not well understood. However, for adult-onset autoimmune disease, at least some of the cause is usually ascribed to sex hormones. This is because levels of sex hormones are one of the most obvious physiological differences between adult males and females, and their impact on immune system function is well recognised. While for paediatric-onset autoimmune diseases a sex bias is not as common, there are several such diseases for which one sex predominates. For example, the oligoarticular subtype of juvenile idiopathic arthritis (JIA) occurs in approximately three times more girls than boys, with a peak age of onset well before the onset of puberty, and at a time when levels of androgen and oestrogen are low and not strikingly different between the sexes. Here, we review potential explanations for autoimmune disease sex bias with a particular focus on paediatric autoimmune disease, and biological mechanisms outside of sex hormone differences. Copyright © 2016 Elsevier Ltd. All rights reserved.
Cognitive representations of sexual self differ as a function of gender and sexual debut.
Lindgren, Kristen P; Schacht, Rebecca L; Mullins, Peter M; Blayney, Jessica A
2011-02-01
This research evaluated the association between gender and sexual debut (initial sexual intercourse) and indirect measures of sexuality. A sample of 440 U.S. college students (pre-sexual debut: 144 women, 153 men; post-sexual debut: 49 women, 94 men) completed the Sexual Self-Schema Scale (SSSS), which assessed cognitive representations about sexual aspects of oneself, and three Implicit Association Tests (IAT), which measured the strength of the associations between the concepts of self + sex, women + sex, and men + sex. Results replicated previous findings that (1) men more strongly associated self + sex and women + sex than did women, and (2) men and women had similarly strong associations of men + sex. Post-sexual debut women's self + sexual and women + sexual associations were stronger than pre-sexual debut women's. Men's associations did not differ significantly as a function of sexual debut. Post-sexual debut women's SSSS scores were more direct, more romantic, and less conservative than pre-sexual debut women's. Post-sexual debut men's SSSS scores were more aggressive and more open-minded than pre-sexual debut men's. Sexual debut appeared to be associated with sexualized and sexually liberal cognitive representations in women and, to a lesser extent, sexually liberal and aggressive cognitive representations in men. Findings were consistent with theories of cognitive consistency and provide preliminary evidence that sexual debut status was associated with differing cognitive representations.
Soleman, Remi S; Schagen, Sebastian E E; Veltman, Dick J; Kreukels, Baudewijntje P C; Cohen-Kettenis, Peggy T; Lambalk, Cornelis B; Wouters, Femke; Delemarre-van de Waal, Henriette A
2013-08-01
In the literature, verbal fluency (VF) is generally described as a female-favoring task. Although it is conceivable that this sex difference only evolves during adolescence or adulthood under influence of sex steroids, this has never been investigated in young adolescents. First, to assess sex differences in VF performance and regional brain activation in adolescents. Second, to determine if untreated transsexual adolescents differ from their sex of birth with regard to VF performance and regional brain activation. Twenty-five boys, 26 girls, 8 Male-to-Female transsexual adolescents (MtFs), and 14 Female-to-Male transsexual adolescents (FtMs) were tested in a cross-sectional study, while performing a phonetic and semantic VF task within an MRI scanner. Functional MRI response during VF task. Boys and girls produced similar amounts of words, but the group MtFs produced significantly more words in the phonetic condition compared to control boys, girls, and FtMs. During the semantic condition, no differences were found. With regard to brain activity, control boys showed more activation in the right Rolandic operculum, a small area adjacent to Broca's area, compared to girls. No significant differences in brain activity were found comparing transsexual adolescents, although sub-threshold activation was found in the right Rolandic operculum indicating a trendwise increase in activation from control girls to FtMs to MtFs to control boys. The better performance of MtFs is consistent with our expectation that MtFs perform better on female-favoring tasks. Moreover, they produced more words than girls and FtMs. Even though a trendwise linear increase in brain activity between the four groups only approached significance, it may indicate differences in individuals with gender identity disorder compared to their birth sex. Although our findings should thus be interpreted with caution, they suggest a biological basis for both transgender groups performing in-between the two sexes. © 2013 International Society for Sexual Medicine.
Age-related sex differences in language lateralization: A magnetoencephalography study in children.
Yu, Vickie Y; MacDonald, Matt J; Oh, Anna; Hua, Gordon N; De Nil, Luc F; Pang, Elizabeth W
2014-09-01
It is well supported by behavioral and neuroimaging studies that typical language function is lateralized to the left hemisphere in the adult brain and this laterality is less well defined in children. The behavioral literature suggests there maybe be sex differences in language development, but this has not been examined systematically with neuroimaging. In this study, magnetoencephalography was used to investigate the spatiotemporal patterns of language lateralization as a function of age and sex. Eighty typically developing children (46 female, 34 male; 4-18 years) participated in an overt visual verb generation task. An analysis method called differential beamforming was used to analyze language-related changes in oscillatory activity referred to as low-gamma event-related desynchrony (ERD). The proportion of ERD over language areas relative to total ERD was calculated. We found different patterns of laterality between boys and girls. Boys showed left-hemisphere lateralization in the frontal and temporal language-related areas across age groups, whereas girls showed a more bilateral pattern, particularly in frontal language-related areas. Differences in patterns of ERD were most striking between boys and girls in the younger age groups, and these patterns became more similar with increasing age, specifically in the preteen years. Our findings show sex differences in language lateralization during childhood; however, these differences do not seem to persist into adulthood. We present possible explanations for these differences. We also discuss the implications of these findings for presurgical language mapping in children and highlight the importance of examining the question of sex-related language differences across development.
Hong, Jui-Yang; Kilpatrick, Lisa A; Labus, Jennifer S; Gupta, Arpana; Katibian, David; Ashe-McNalley, Cody; Stains, Jean; Heendeniya, Nuwanthi; Smith, Suzanne R; Tillisch, Kirsten; Naliboff, Bruce; Mayer, Emeran A
2014-10-22
Resting-state functional magnetic resonance imaging has been used to investigate intrinsic brain connectivity in healthy subjects and patients with chronic pain. Sex-related differences in the frequency power distribution within the human insula (INS), a brain region involved in the integration of interoceptive, affective, and cognitive influences, have been reported. Here we aimed to test sex and disease-related alterations in the intrinsic functional connectivity of the dorsal anterior INS. The anterior INS is engaged during goal-directed tasks and modulates the default mode and executive control networks. By comparing functional connectivity of the dorsal anterior INS in age-matched female and male healthy subjects and patients with irritable bowel syndrome (IBS), a common chronic abdominal pain condition, we show evidence for sex and disease-related alterations in the functional connectivity of this region: (1) male patients compared with female patients had increased positive connectivity of the dorsal anterior INS bilaterally with the medial prefrontal cortex (PFC) and dorsal posterior INS; (2) female patients compared with male patients had greater negative connectivity of the left dorsal anterior INS with the left precuneus; (3) disease-related differences in the connectivity between the bilateral dorsal anterior INS and the dorsal medial PFC were observed in female subjects; and (4) clinical characteristics were significantly correlated to the insular connectivity with the dorsal medial PFC in male IBS subjects and with the precuneus in female IBS subjects. These findings are consistent with the INS playing an important role in modulating the intrinsic functional connectivity of major networks in the resting brain and show that this role is influenced by sex and diagnosis. Copyright © 2014 the authors 0270-6474/14/3414252-08$15.00/0.
Wang, Ningjian; Zhang, Kun; Han, Bing; Li, Qin; Chen, Yi; Zhu, Chunfang; Chen, Yingchao; Xia, Fangzhen; Zhai, Hualing; Jiang, Boren; Shen, Zhoujun; Lu, Yingli
2017-06-01
Follicle stimulating hormone plays direct roles in a variety of nongonadal tissues and sex hormone binding globulin is becoming the convergence of the crosstalk among metabolic diseases. However, no studies have explored the association between follicle stimulating hormone and sex hormone binding globulin. We aimed to study this association among men and women. SPECT-China is a population-based study conducted since 2014. This study included 4206 men and 2842 postmenopausal women. Collected serum was assayed for gonadotropins, sex hormone binding globulin, sex hormones etc. Regression analyses were performed to assess the relationship between sex hormone binding globulin and follicle stimulating hormone and other variables including metabolic factors, thyroid function and sex hormones. Treatment with follicle stimulating hormone at different concentrations of 0, 5, 50 and 100 IU/L for 24 h was performed in HepG2 cells. In Spearman correlation, sex hormone binding globulin was significantly correlated with FSH, triglycerides, thyroxins, body mass index and blood pressure in men and postmenopausal women (all P < 0.05). In regression analyses, follicle stimulating hormone was a significant predictor of sex hormone binding globulin in men and postmenopausal women (P < 0.05), independent of above variables. Follicle stimulating hormone induced sex hormone binding globulin expression in a dose-dependent fashion in HepG2 cells. Serum follicle stimulating hormone levels were positively associated with circulating sex hormone binding globulin levels in men and postmenopausal women. This association is independent of age, insulin resistance, hepatic function, lipid profile, thyroid function, adiposity, blood pressure, and endogenous sex hormones.
Sex Steroid Signaling: Implications for Lung Diseases
Sathish, Venkatachalem; Martin, Yvette N.; Prakash, Y.S.
2015-01-01
There is increasing recognition that the sex hormones (estrogen, progesterone, and testosterone) have biological and pathophysiological actions in peripheral, non-reproductive organs, including the lung. Clinically, sex differences in the incidence, morbidity and mortality of lung diseases such as asthma, chronic obstructive pulmonary disease (COPD), pulmonary fibrosis, lung cancer and pulmonary hypertension have been noted, although intrinsic sex differences vs. the roles of sex steroids are still not well-understood. Accordingly, it becomes important to ask the following questions: 1) Which sex steroids are involved? 2) How do they affect different components of the lung under normal circumstances? 3) How does sex steroid signaling change in or contribute to lung disease, and in this regard, are sex steroids detrimental or beneficial? As our understanding of sex steroid signaling in the lung improves, it is important to consider whether such information can be used to develop new therapeutic strategies to target lung diseases, perhaps in both sexes or in a sex-specific manner. In this review, we focus on the basics of sex steroid signaling, and the current state of knowledge regarding how they influence structure and function of specific lung components across the life span and in the context of some important lung diseases. We then summarize the potential for sex steroids as useful biomarkers and therapeutic targets in these lung diseases as a basis for future translational research in the area of gender and individualized medicine. PMID:25595323
Mendrek, Adrianna; Mancini-Marië, Adham; Fahim, Cherine; Stip, Emmanuel
2007-02-01
Impaired processing of various emotions is considered one of the fundamental features of schizophrenia. In the recent study intriguing sex differences were observed in the cerebral function associated with the experience of sadness in schizophrenia patients. The aim of the present study was to explore this phenomenon during exposure to aversive stimuli. Fifteen men and 10 women with the DSM-IV diagnosis of schizophrenia underwent functional magnetic resonance imaging (fMRI) while viewing alternating blocks of negative and neutral pictures. Data were analysed using random-effects model within statistical parametric mapping (SPM99) software. Processing of negative stimuli evoked significantly greater activations in men in the thalamus, cerebellum, temporal, occipital and posterior cingulate cortex, while women exhibited greater activations in the left middle frontal gyrus. The sex differences in the cerebral activations in schizophrenia patients deviate from what has been observed in the general population during exposure and experience of negative affect. As such the present study supports and extends the authors' preliminary observation of the anomalous sexual dimorphism in schizophrenia at the functional neuroanatomical level, suggesting potential masculinization of female subjects and feminization of male subjects with schizophrenia.
Sex differences in the association between gray matter volume and verbal creativity.
Shi, Baoguo; Xu, Li; Chen, Qunlin; Qiu, Jiang
2017-08-02
The explanation for why significant sex differences are found in creativity has become an increasingly important topic. The current study applied a cognitive neuroscience perspective and voxel-based morphometry to investigate the sex differences for the association between verbal creativity and gray matter volume (GMV) in a large sample of healthy adults from the Chinese Mainland (163 men and 193 women). Furthermore, we sought to determine which brain regions are responsible for these differences. Our behavioral results showed a significant sex difference. Specifically, women scored higher than men on originality. The voxel-based morphometry results indicated that the relationship between originality and GMV differed between men and women in the left temporo-occipital junction. Higher originality scores in women were associated with more GMV. In contrast, higher originality scores in men were related to less GMV. These findings suggest the left temporo-occipital junction GMV plays a unique role in the sex differences in verbal creativity because women usually surpass men in semantic processing, which is the major function of the left temporal region.
Looking, Smiling, Laughing, and Moving in Restaurants: Sex and Age Differences.
ERIC Educational Resources Information Center
Adams, Robert M.; Kirkevold, Barbara
Body movements and facial expressions of males and females in a restaurant setting were examined, with the goal of providing differences in frequency as a function of age and sex. The subjects (N-197 males and N=131 females) were seated in three Seattle fast food restaurants and were selected on a semi-random basis and then observed for three…
ERIC Educational Resources Information Center
Sommer, Iris E. C.; Aleman, Andre; Bouma, Anke; Kahn, Rene S.
2004-01-01
Sex differences in cognition are consistently reported, men excelling in most visuospatial tasks and women in certain verbal tasks. It has been hypothesized that these sex differences in cognition results from a more bilateral pattern of language representation in women than in men. This bilateral pattern of language representation in women is…
Riccardi, Patrizia; Park, Sohee; Anderson, Sharlet; Doop, Mikisha; Ansari, M Sib; Schmidt, Dennis; Baldwin, Ronald
2011-02-01
The purpose of this study was to examine sex differences in the correlations of d-amphetamine (d-AMPH) induced displacements of [¹⁸F]fallypride in striatal and extrastriatal regions in relation to affect and cognition. Seven male and six female healthy subjects, whose mean age was 25.9 years, underwent positron emission tomography (PET) with [¹⁸F]fallypride at baseline and 3 h after a 0.43 mg/kg oral dose of d-AMPH. Percent displacements in striatal and extrastriatal regions were calculated using regions of interest (ROI) analysis and on a pixel-by-pixel basis. Subjects underwent neuropsychological testing prior to the baseline PET study and one hour after d-AMPH administration for the second PET. In order to examine the subjective effect of d-AMPH, subjects rated PANAS at baseline and after administration of amphetamine. Correlations of changes in cognition and affect with regional dopamine (DA) release revealed several significant sex related differences. The results of this study demonstrate in vivo sex related differences in the relationship of regional DA release to affect and cognitive function. Copyright © 2010 Wiley-Liss, Inc.
Sex differences in extinction recall in posttraumatic stress disorder: A pilot fMRI study
Shvil, Erel; Sullivan, Gregory M.; Schafer, Scott; Markowitz, John C.; Campeas, Miriam; Wager, Tor D.; Milad, Mohammed R.; Neria, Yuval
2014-01-01
Recent research has found that individuals with posttraumatic stress disorder (PTSD) exhibit an impaired memory of fear extinction compounded by deficient functional activation of key nodes of the fear network including the amygdala, hippocampus, ventromedial prefrontal cortex (vmPFC) and dorsal anterior cingulate cortex (dACC). Research has shown these regions are sexually dimorphic and activate differentially in healthy men and women during fear learning tasks. To explore biological markers of sex differences following exposure to psychological trauma, we used a fear learning and extinction paradigm together with functional magnetic resonance imaging (fMRI) and skin conductance response (SCR) to assess 31 individuals with PTSD (18 women; 13 men) and 25 matched trauma-exposed healthy control subjects (13 women; 12 men). Whereas no sex differences appeared within the trauma-exposed healthy control group, both psychophysiological and neural activation patterns within the PTSD group indicated deficient recall of extinction memory among men and not among women. Men with PTSD exhibited increased activation in the left rostral dACC during extinction recall compared with women with PTSD. These findings highlight the importance of tracking sex differences in fear extinction when characterizing the underlying neurobiological mechanisms of PTSD psychopathology. PMID:24560771
Sex differences in psychological adjustment from infancy to 8 years.
Prior, M; Smart, D; Sanson, A; Oberklaid, F
1993-03-01
The objective of this study was to explore sex differences in development from infancy to 8 years of age in a community sample. Measures of biological, social, interactive, and parental functioning as well as teacher reports were obtained. There were minimal differences in infancy, but major psychosocial differences emerged with increasing age. In the biological sphere boys were disadvantaged only in ratings of language and motor skills at 3 to 4 years old. They showed greater temperamental "difficulty" and low persistence factor scores from 5 years onward. Boys were significantly more likely to have problems with adaptive behavior and social competence and to show behavior problems of the hyperactive and aggressive type, as rated by mothers. Parent and family functioning measures did not differentiate between the sexes. Teachers rated boys as having more problems in academic and behavioral domains the first 3 years of school. Path analyses combining data sets gathered when the children were 3 to 8 years old demonstrated the differential courses of development for boys and girls although temperamental flexibility was the best predictor of behavioral adjustment for both sexes. A social learning explanation of the increased incidence of problems among males is supported, although biological influences are not ruled out.
ERIC Educational Resources Information Center
Lee, Nancy Raitano; Wallace, Gregory L.; Adeyemi, Elizabeth I.; Lopez, Katherine C.; Blumenthal, Jonathan D.; Clasen, Liv S.; Giedd, Jay N.
2012-01-01
Background: Supernumerary sex chromosome aneuploidies (X/Y-aneuploidies), the presence of extra X and/or Y chromosomes, are associated with heightened rates of language impairments and social difficulties. However, no single study has examined different language domains and social functioning in the same sample of children with tri-, tetra-, and…
Sex-specific phenotypes of hyperthyroidism and hypothyroidism in aged mice.
Rakov, Helena; Engels, Kathrin; Hönes, Georg Sebastian; Brix, Klaudia; Köhrle, Josef; Moeller, Lars Christian; Zwanziger, Denise; Führer, Dagmar
2017-12-22
Sex and age play a role in the prevalence of thyroid dysfunction (TD), but their interrelationship for manifestation of hyper- and hypothyroidism is still not well understood. Using a murine model, we asked whether sex impacts the phenotypes of hyper- and hypothyroidism at two life stages. Hyper- and hypothyroidism were induced by i.p. T4 or MMI/ClO 4 -/LoI treatment over 7 weeks in 12- and 20-months-old female and male C57BL/6N mice. Control animals underwent PBS treatment (n = 7-11 animals/sex/treatment). Animals were investigated for impact of sex on body weight, food and water intake, body temperature, heart rate, behaviour (locomotor activity, motor coordination and strength) and serum thyroid hormone (TH) status. Distinct sex impact was found in eu- and hyperthyroid mice, while phenotypic traits of hypothyroidism were similar in male and female mice. No sex difference was found in TH status of euthyroid mice; however, T4 treatment resulted in twofold higher TT4, FT4 and FT3 serum concentrations in adult and old females compared to male animals. Hyperthyroid females consistently showed higher locomotor activity and better coordination but more impairment of muscle function by TH excess at adult age. Importantly and in contrast to male mice, adult and old hyperthyroid female mice showed increased body weight. Higher body temperature in female mice was confirmed in all age groups. No sex impact was found on heart rate irrespective of TH status in adult and old mice. By comparison of male and female mice with TD at two life stages, we found that sex modulates TH action in an organ- and function-specific manner. Sex differences were more pronounced under hyperthyroid conditions. Importantly, sex-specific differences in features of TD in adult and old mice were not conclusively explained by serum TH status in mice.
[Sex differentiation in plants. Terms and notions].
Godin, V N
2007-01-01
There are two methodological approaches to the study of sex in plants: the descriptive and morphological approach and the quantitative approach. The former is based exclusively on external morphological peculiarities of the generative organs of the flower, the latter is based on the functioning of individuals as parents of the coming generation. It has been suggested to recognize three flower types: staminate, pistillate, and complete. Depending on the distribution pattern of the flowers of different sex type, there are monomorphic populations (all individuals form flowers of the same type) and heteromorphic populations (individuals have flowers of different types). Monomorphic populations include monoclinous, monoecious, gynomonoecious, andromonoecious, and polygamomonoecious ones. Among heteromorphic populations, dioecious, polygamodioecious, subdioecious, paradioecious, and trioecious ones are recognized. It is desirable to give up the usage of such terms as "bisexual", "polygamous", "functionally female", and "functionally male" flowers, "temporary dioecy" and some others. The notion "gender" has been established in English-language works for describing the sex quantitavely; two additional terms have been proposed: "phenotypic gender" and "functional gender". The recently developed quantitative approach is at present in the process of accumulating material, and in need of the further elaborating the methodological base for research. Analysis of the principal notions shows the necessity to form their integrated structure and to correct the usage of the existing and new terms.
Salehi, Mehraveh; Karbasi, Amin; Shen, Xilin; Scheinost, Dustin; Constable, R. Todd
2018-01-01
Recent work with functional connectivity data has led to significant progress in understanding the functional organization of the brain. While the majority of the literature has focused on group-level parcellation approaches, there is ample evidence that the brain varies in both structure and function across individuals. In this work, we introduce a parcellation technique that incorporates delineation of functional networks both at the individual- and group-level. The proposed technique deploys the notion of “submodularity” to jointly parcellate the cerebral cortex while establishing an inclusive correspondence between the individualized functional networks. Using this parcellation technique, we successfully established a cross-validated predictive model that predicts individuals’ sex, solely based on the parcellation schemes (i.e. the node-to-network assignment vectors). The sex prediction finding illustrates that individualized parcellation of functional networks can reveal subgroups in a population and suggests that the use of a global network parcellation may overlook fundamental differences in network organization. This is a particularly important point to consider in studies comparing patients versus controls or even patient subgroups. Network organization may differ between individuals and global configurations should not be assumed. This approach to the individualized study of functional organization in the brain has many implications for both neuroscience and clinical applications. PMID:28882628
Sex differences in analgesic, reinforcing, discriminative, and motoric effects of opioids.
Craft, Rebecca M
2008-10-01
This review summarizes evidence for sex differences in behavioral effects of opioids, primarily in rats. Whereas micro agonists have been found to be more potent and in some cases more efficacious in producing analgesia and sedation in males than females, females are more sensitive than males to reinforcing and locomotor stimulant effects of opioids. Sex differences in motoric effects of opioids may contribute to sex differences in other behavioral effects of opioids; for example, sex differences in rats' ability to discriminate morphine from saline can be attributed entirely to greater morphine-induced sedation in males. Chronic estradiol blunts females' sensitivity to morphine's analgesic and sedative effects, but enhances females' sensitivity to the reinforcing and locomotor stimulant effects of micro opioids. The neurobiological basis for sex differences in and estradiol modulation of behavioral effects of opioids includes brain opioid receptor density (greater in males and under low-estradiol conditions in females) and dopaminergic function (greater in females and under high-estradiol conditions). Given the significant and growing use of opioids by women, both medicinally and recreationally, understanding how female biology influences analgesic and other effects of opioids is crucial. Copyright (c) 2008 APA, all rights reserved.
Sex-Based Differences in Skeletal Muscle Kinetics and Fiber-Type Composition
Haizlip, K. M.; Harrison, B. C.
2015-01-01
Previous studies have identified over 3,000 genes that are differentially expressed in male and female skeletal muscle. Here, we review the sex-based differences in skeletal muscle fiber composition, myosin heavy chain expression, contractile function, and the regulation of these physiological differences by thyroid hormone, estrogen, and testosterone. The findings presented lay the basis for the continued work needed to fully understand the skeletal muscle differences between males and females. PMID:25559153
Does sex influence the diagnostic evaluation of autism spectrum disorder in adults?
Wilson, C Ellie; Murphy, Clodagh M; McAlonan, Grainne; Robertson, Dene M; Spain, Debbie; Hayward, Hannah; Woodhouse, Emma; Deeley, P Quinton; Gillan, Nicola; Ohlsen, J Chris; Zinkstok, Janneke; Stoencheva, Vladimira; Faulkner, Jessica; Yildiran, Hatice; Bell, Vaughan; Hammond, Neil; Craig, Michael C; Murphy, Declan Gm
2016-10-01
It is unknown whether sex influences the diagnostic evaluation of autism spectrum disorder, or whether male and female adults within the spectrum have different symptom profiles. This study reports sex differences in clinical outcomes for 1244 adults (935 males and 309 females) referred for autism spectrum disorder assessment. Significantly, more males (72%) than females (66%) were diagnosed with an autism spectrum disorder of any subtype (x(2) = 4.09; p = 0.04). In high-functioning autism spectrum disorder adults (IQ > 70; N = 827), there were no significant sex differences in severity of socio-communicative domain symptoms. Males had significantly more repetitive behaviours/restricted interests than females (p = 0.001, d = 0.3). A multivariate analysis of variance indicated a significant interaction between autism spectrum disorder subtype (full-autism spectrum disorder/partial-autism spectrum disorder) and sex: in full-autism spectrum disorder, males had more severe socio-communicative symptoms than females; for partial-autism spectrum disorder, the reverse was true. There were no sex differences in prevalence of co-morbid psychopathologies. Sex influenced diagnostic evaluation in a clinical sample of adults with suspected autism spectrum disorder. The sexes may present with different manifestations of the autism spectrum disorder phenotype and differences vary by diagnostic subtype. Understanding and awareness of adult female repetitive behaviours/restricted interests warrant attention and sex-specific diagnostic assessment tools may need to be considered. © The Author(s) 2016.
Does sex influence the diagnostic evaluation of autism spectrum disorder in adults?
Wilson, C Ellie; Murphy, Clodagh M; McAlonan, Grainne; Robertson, Dene M; Spain, Debbie; Hayward, Hannah; Woodhouse, Emma; Deeley, P Quinton; Gillan, Nicola; Ohlsen, J Chris; Zinkstok, Janneke; Stoencheva, Vladimira; Faulkner, Jessica; Yildiran, Hatice; Bell, Vaughan; Hammond, Neil; Craig, Michael C; Murphy, Declan GM
2016-01-01
It is unknown whether sex influences the diagnostic evaluation of autism spectrum disorder, or whether male and female adults within the spectrum have different symptom profiles. This study reports sex differences in clinical outcomes for 1244 adults (935 males and 309 females) referred for autism spectrum disorder assessment. Significantly, more males (72%) than females (66%) were diagnosed with an autism spectrum disorder of any subtype (x2 = 4.09; p = 0.04). In high-functioning autism spectrum disorder adults (IQ > 70; N = 827), there were no significant sex differences in severity of socio-communicative domain symptoms. Males had significantly more repetitive behaviours/restricted interests than females (p = 0.001, d = 0.3). A multivariate analysis of variance indicated a significant interaction between autism spectrum disorder subtype (full-autism spectrum disorder/partial-autism spectrum disorder) and sex: in full-autism spectrum disorder, males had more severe socio-communicative symptoms than females; for partial-autism spectrum disorder, the reverse was true. There were no sex differences in prevalence of co-morbid psychopathologies. Sex influenced diagnostic evaluation in a clinical sample of adults with suspected autism spectrum disorder. The sexes may present with different manifestations of the autism spectrum disorder phenotype and differences vary by diagnostic subtype. Understanding and awareness of adult female repetitive behaviours/restricted interests warrant attention and sex-specific diagnostic assessment tools may need to be considered. PMID:26802113
2016-01-01
We aimed to analyse the mechanical properties of skinned single muscle fibres derived from the vastus lateralis (VL) muscle in relation to those of the whole intact thigh muscle and to compare any difference between young and older adults. Sixteen young men (29.25 ± 4.65 years), 11 older men (71.45 ± 2.94 years), 11 young women (29.64 ± 4.88 years), and 7 older women (67.29 ± 1.70 years) were recruited. In vivo analyses were performed for mechanical properties such as isokinetic performance, isometric torque, and power. Specific force and maximum shortening velocity (Vo) were measured with single muscle fibres. Sex difference showed greater impact on the functional properties of both the whole muscle (p < 0.01) and single muscle fibres than aging (p < 0.05). Sex difference, rather than aging, yielded more remarkable differences in gross mechanical properties in the single muscle fibre study in which significant differences between young men and young women were found only in the cross-sectional area and Vo (p < 0.05). Age and sex differences reflect the mechanical properties of both single muscle fibres and whole thigh muscle, with the whole muscle yielding more prominent functional properties. PMID:28070513
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
Differentiation of subspecies and sexes of Beringian Dunlins using morphometric measures
Gates, H. River; Yezerinac, Stephen; Powell, Abby N.; Tomkovich, Pavel S.; Valchuk, Olga P.; Lanctot, Richard B.
2013-01-01
Five subspecies of Dunlins (Calidris alpina) that breed in Beringia are potentially sympatric during the non-breeding season. Studying their ecology during this period requires techniques to distinguish individuals by subspecies. Our objectives were to determine (1) if five morphometric measures (body mass, culmen, head, tarsus, and wing chord) differed between sexes and among subspecies (C. a. actites, arcticola, kistchinski, pacifica, and sakhalina), and (2) if these differences were sufficient to allow for correct classification of individuals using equations derived from discriminant function analyses. We conducted analyses using morphometric data from 10 Dunlin populations breeding in northern Russia and Alaska, USA. Univariate tests revealed significant differences between sexes in most morphometric traits of all subspecies, and discriminant function equations predicted the sex of individuals with an accuracy of 83–100% for each subspecies. We provide equations to determine sex and subspecies of individuals in mixed subspecies groups, including the (1) Western Alaska group of arcticola and pacifica (known to stage together in western Alaska) and (2) East Asia group of arcticola, actites, kistchinski, and sakhalina (known to winter together in East Asia). Equations that predict the sex of individuals in mixed groups had classification accuracies between 75% and 87%, yielding reliable classification equations. We also provide equations that predict the subspecies of individuals with an accuracy of 22–96% for different mixed subspecies groups. When the sex of individuals can be predetermined, the accuracy of these equations is increased substantially. Investigators are cautioned to consider limitations due to age and feather wear when using these equations during the non-breeding season. These equations will allow determination of sexual and subspecies segregation in non-breeding areas, allowing implementation of taxonomic-specific conservation actions.
Blood pressure, brain structure, and cognition: opposite associations in men and women.
Cherbuin, Nicolas; Mortby, Moyra E; Janke, Andrew L; Sachdev, Perminder S; Abhayaratna, Walter P; Anstey, Kaarin J
2015-02-01
Research on associations between blood pressure, brain structure, and cognitive function has produced somewhat inconsistent results. In part, this may be due to differences in age ranges studied and because of sex differences in physiology and/or exposure to risk factors, which may lead to different time course or patterns in cardiovascular disease progression. The aim of this study was to investigate the impact of sex on associations between blood pressure, regional cerebral volumes, and cognitive function in older individuals. In this cohort study, brachial blood pressure was measured twice at rest in 266 community-based individuals free of dementia aged 68-73 years who had also undergone a brain scan and a neuropsychological assessment. Associations between mean blood pressure (MAP), regional brain volumes, and cognition were investigated with voxel-wise regression analyses. Positive associations between MAP and regional volumes were detected in men, whereas negative associations were found in women. Similarly, there were sex differences in the brain-volume cognition relationship, with a positive relationship between regional brain volumes associated with MAP in men and a negative relationship in women. In this cohort of older individuals, higher MAP was associated with larger regional volume and better cognition in men, whereas opposite findings were demonstrated in women. These effects may be due to different lifetime risk exposure or because of physiological differences between men and women. Future studies investigating the relationship between blood pressure and brain structure or cognitive function should evaluate the potential for differential sex effects. © American Journal of Hypertension, Ltd 2014. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Sex-specific neural circuits of emotion regulation in the centromedial amygdala.
Wu, Yan; Li, Huandong; Zhou, Yuan; Yu, Jian; Zhang, Yuanchao; Song, Ming; Qin, Wen; Yu, Chunshui; Jiang, Tianzi
2016-03-23
Sex-related differences in emotion regulation (ER) in the frequency power distribution within the human amygdala, a brain region involved in emotion processing, have been reported. However, how sex differences in ER are manifested in the brain networks which are seeded on the amygdala subregions is unclear. The goal of this study was to investigate this issue from a brain network perspective. Utilizing resting-state functional connectivity (RSFC) analysis, we found that the sex-specific functional connectivity patterns associated with ER trait level were only seeded in the centromedial amygdala (CM). Women with a higher trait-level ER had a stronger negative RSFC between the right CM and the medial superior frontal gyrus (mSFG), and stronger positive RSFC between the right CM and the anterior insula (AI) and the superior temporal gyrus (STG). But men with a higher trait-level ER was associated with weaker negative RSFC of the right CM-mSFG and positive RSFCs of the right CM-left AI, right CM-right AI/STG, and right CM-left STG. These results provide evidence for the sex-related effects in ER based on CM and indicate that men and women may differ in the neural circuits associated with emotion representation and integration.
Palatal rugae pattern: An aid for sex identification
Gadicherla, Prahlad; Saini, Divya; Bhaskar, Milana
2017-01-01
Background: Palatal rugoscopy, or palatoscopy, is the process by which human identification can be obtained by inspecting the transverse palatal rugae inside the mouth. Aim: The aim of the study is to investigate the potential of using palatal rugae as an aid for sex identification in Bengaluru population. Materials and Methods: One hundred plaster casts equally distributed between males and females belonging to age range of 4–16 years were examined for different rugae patterns. Thomas and Kotze classification was adopted for identification of these rugae patterns. Statistical Analysis: The data obtained were subjected to discriminant function analysis to determine the applicability of palatal rugae pattern as an aid for sex identification. Results: Difference in unification patterns among males and females was found to be statistically significant. No significant difference was found between males and females in terms of number of rugae. Overall, wavy and curvy were the most predominant type of rugae seen. Discriminant function analysis enabled sex identification with an accuracy of 80%. Conclusion: This preliminary study undertaken showed the existence of a distinct pattern of distribution of palatal rugae between males and females of Bengaluru population. This study opens scope for further research with a larger sample size to establish palatal rugae as a valuable tool for sex identification for forensic purposes. PMID:28584485
Reconceptualizing sex, brain and psychopathology: interaction, interaction, interaction
Joel, D; Yankelevitch-Yahav, R
2014-01-01
In recent years there has been a growing recognition of the influence of sex on brain structure and function, and in relation, on the susceptibility, prevalence and response to treatment of psychiatric disorders. Most theories and descriptions of the effects of sex on the brain are dominated by an analogy to the current interpretation of the effects of sex on the reproductive system, according to which sex is a divergence system that exerts a unitary, overriding and serial effect on the form of other systems. We shortly summarize different lines of evidence that contradict aspects of this analogy. The new view that emerges from these data is of sex as a complex system whose different components interact with one another and with other systems to affect body and brain. The paradigm shift that this understanding calls for is from thinking of sex in terms of sexual dimorphism and sex differences, to thinking of sex in terms of its interactions with other factors and processes. Our review of data obtained from animal models of psychopathology clearly reveals the need for such a paradigmatic shift, because in the field of animal behaviour whether a sex difference exists and its direction depend on the interaction of many factors including, species, strain, age, specific test employed and a multitude of environmental factors. We conclude by explaining how the new conceptualization can account for sex differences in psychopathology. 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:24758640
Vossbrinck, Madeline; Zeig-Owens, Rachel; Hall, Charles B; Schwartz, Theresa; Moir, William; Webber, Mayris P; Cohen, Hillel W; Nolan, Anna; Weiden, Michael D; Christodoulou, Vasilios; Kelly, Kerry J; Aldrich, Thomas K; Prezant, David J
2017-03-01
To determine whether lung function trajectories after 9/11/2001 (9/11) differed by sex or race/ethnicity in World Trade Center-exposed Fire Department of the City of New York emergency medical service (EMS) workers. Serial cross-sectional study of pulmonary function tests (PFTs) taken between 9/11 and 9/10/2015. We used data from routine PFTs (forced expiratory volume in 1 s (FEV 1 ) and FEV 1 % predicted), conducted at 12-18 month intervals. FEV 1 and FEV 1 % predicted were assessed over time, stratified by sex, and race/ethnicity. We also assessed FEV 1 and FEV 1 % predicted in current, former and never-smokers. Among 1817 EMS workers, 334 (18.4%) were women, 979 (53.9%) self-identified as white and 939 (51.6%) were never-smokers. The median follow-up was 13.1 years (IQR 10.5-13.6), and the median number of PFTs per person was 11 (IQR 7-13). After large declines associated with 9/11, there was no discernible recovery in lung function. In analyses limited to never-smokers, the trajectory of decline in adjusted FEV 1 and FEV 1 % predicted was relatively parallel for men and women in the 3 racial/ethnic groups. Similarly, small differences in FEV 1 annual decline between groups were not clinically meaningful. Analyses including ever-smokers were essentially the same. 14 years after 9/11, most EMS workers continued to demonstrate a lack of lung function recovery. The trajectories of lung function decline, however, were parallel by sex and by race/ethnicity. These findings support the use of routine, serial measures of lung function over time in first responders and demonstrate no sex or racial sensitivity to exposure-related lung function decline. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.
Wetherill, Reagan R; Jagannathan, Kanchana; Hager, Nathan; Childress, Anna Rose; Franklin, Teresa R
2015-08-01
Preclinical and clinical research indicates that there are sex differences in how men and women initiate, progress, respond to, and withdraw from cannabis use; however, neurophysiological differences, such as neural responses to cannabis cues, are not well understood. Using functional MRI and an event-related blood oxygen level-dependent backward-masking task, we compared neural responses to backward-masked cannabis cues to neutral cues in treatment-seeking, cannabis-dependent adults (N = 44; 27 males) and examined whether sex differences exist. In addition, functional MRI findings were correlated with cannabis craving. Backward-masked cannabis cues elicited greater neural responses than neutral cues in reward-related brain regions, including the striatum, hippocampus/amygdala, insula, anterior cingulate cortex, and lateral orbitofrontal cortex, p < .01, k > 121 voxels. Although no significant sex differences in neural responses to cannabis cues emerged, women showed a positive correlation between neural responses to cannabis cues in the bilateral insula and cannabis craving and an inverse correlation between neural responses to cannabis cues in the left lateral orbitofrontal cortex and cannabis craving. Men, however, showed a positive correlation between neural responses to cannabis cues in the striatum and cannabis craving. Given that cues and craving are important triggers and the focus on many behavioral treatment approaches, these findings suggest that treatment-seeking, cannabis-dependent men and women may benefit from sex-specific and tailored cannabis use disorder treatments. (c) 2015 APA, all rights reserved).
Fagot, Delphine; Chicherio, Christian; Albinet, Cédric T; André, Nathalie; Audiffren, Michel
2017-09-04
It is well-known that processing speed and executive functions decline with advancing age. However, physical activity (PA) has a positive impact on cognitive performances in aging, specifically for inhibition. Less is known concerning intraindividual variability (iiV) in reaction times. This study aims to investigate the influence of PA and sex differences on iiV in inhibitory performance during aging. Healthy adults were divided into active and sedentary groups according to PA level. To analyse iiV in reaction times, individual mean, standard deviation and the ex-Gaussian parameters were considered. An interaction between activity level and sex was revealed, sedentary females being slower and more variable than sedentary men. No sex differences were found in the active groups. These results indicate that the negative impact of sedentariness on cognitive performance in older age is stronger for females. The present findings underline the need to consider sex differences in active aging approaches.
Sex differences in the functional lateralization of emotion and decision making in the human brain.
Reber, Justin; Tranel, Daniel
2017-01-02
Dating back to the case of Phineas Gage, decades of neuropsychological research have shown that the ventromedial prefrontal cortex (vmPFC) is crucial to both real-world social functioning and abstract decision making in the laboratory (see, e.g., Stuss et al., ; Bechara et al., 1994; Damasio et al., ). Previous research has shown that the relationship between the laterality of individuals' vmPFC lesions and neuropsychological performance is moderated by their sex, whereby there are more severe social, emotional, and decision-making impairments in men with right-side vmPFC lesions and in women with left-side vmPFC lesions (Tranel et al., 2005; Sutterer et al., 2015). We conducted a selective review of studies examining the effect of vmPFC lesions on emotion and decision making and found further evidence of sex-related differences in the lateralization of function not only in the vmPFC but also in other neurological structures associated with decision making and emotion. This Mini-Review suggests that both sex and laterality effects warrant more careful consideration in the scientific literature. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Göppert, Carolin; Harris, Rayna M; Theis, Anya; Boila, Anna; Hohl, Simon; Rüegg, Attila; Hofmann, Hans A; Salzburger, Walter; Böhne, Astrid
2016-01-01
Sex steroids are major drivers of sexual development and also responsible for the maintenance of the established gender. Especially fishes exhibit great plasticity and less conservation in sex determination and sexual development compared to other vertebrate groups. In addition, fishes have a constant sex steroid production throughout their entire lifespan, which makes them particularly susceptible to interferences with the endogenous sex steroid system. This susceptibility has recently been used to show that inhibition of the key enzyme of estrogen synthesis, aromatase Cyp19a1, can induce functional sex reversal even in adult fish. Here, we investigated the impact of the aromatase inhibitor (AI) fadrozole in adult females of the East African cichlid fish Astatotilapia burtoni. Using gene expression, phenotypic measurements, behavioral experiments, and hormone measurements, we assessed if females treated with fadrozole develop a male-like phenotype. We found that AI treatment has a different effect on gene expression in the gonad compared to the brain, the 2 tissues mostly implicated in sexual development. In contrast to observations in other gonochoristic species, A. burtoni ovaries cannot be transformed into functional testis by AI. However, rapid changes towards a male-like phenotype can be induced with AI in coloration, hormone levels, and behavior. © 2016 S. Karger AG, Basel.
The impact of comorbid mental health symptoms and sex on sleep functioning in children with ADHD.
Becker, Stephen P; Cusick, Caroline N; Sidol, Craig A; Epstein, Jeffery N; Tamm, Leanne
2018-03-01
Children with attention-deficit/hyperactivity disorder (ADHD) display more sleep problems than their peers, but it remains unclear whether comorbid mental health symptoms [i.e., anxiety, depression, oppositional-defiant disorder (ODD)] are uniquely related to sleep functioning. It is also largely unknown whether boys and girls with ADHD differ in their sleep functioning. This study (1) examined whether boys or girls with ADHD differ in their sleep functioning, (2) evaluated comorbid symptoms as uniquely related to sleep functioning domains, and (3) explored whether sex moderated associations between comorbid symptoms and sleep. Participants were 181 children (ages 7-13; 69% male; 82% White) diagnosed with ADHD. Parents completed measures assessing their child's ADHD symptoms, comorbid symptoms, and sleep functioning. Girls had poorer sleep functioning than boys across most sleep functioning domains. Sixty percent of children met cutoff criteria for having sleep problems, though rates differed significantly between girls (75%) and boys (53%). No differences in rates of sleep problems were found between ADHD subtypes/presentations or between younger and older children. In path models including ADHD and comorbid symptom dimensions, anxiety symptoms were uniquely associated with increased bedtime resistance and sleep anxiety, ADHD hyperactive-impulsive symptoms were associated with more night wakings and more parasomnia behaviors, and ODD and depressive symptoms were associated with shorter sleep duration. Depression was also uniquely associated with increased daytime sleepiness and overall sleep problems. Sex did not moderate associations between comorbid symptoms and sleep problems. This study provides important preliminary evidence that girls with ADHD experience more sleep problems than boys with ADHD. Findings also demonstrate that the associations between comorbid symptoms and sleep functioning in children with ADHD vary based on both the specific symptoms and sleep domains examined.
Sex, Gender, and Pain: A Review of Recent Clinical and Experimental Findings
Fillingim, Roger B.; King, Christopher D.; Ribeiro-Dasilva, Margarete C.; Rahim-Williams, Bridgett; Riley, Joseph L.
2009-01-01
Sex-related influences on pain and analgesia have become a topic of tremendous scientific and clinical interest, especially in the last 10 to 15 years. Members of our research group published reviews of this literature more than a decade ago, and the intervening time period has witnessed robust growth in research regarding sex, gender, and pain. Therefore, it seems timely to revisit this literature. Abundant evidence from recent epidemiologic studies clearly demonstrates that women are at substantially greater risk for many clinical pain conditions, and there is some suggestion that postoperative and procedural pain may be more severe among women than men. Consistent with our previous reviews, current human findings regarding sex differences in experimental pain indicate greater pain sensitivity among females compared with males for most pain modalities, including more recently implemented clinically relevant pain models such as temporal summation of pain and intramuscular injection of algesic substances. The evidence regarding sex differences in laboratory measures of endogenous pain modulation is mixed, as are findings from studies using functional brain imaging to ascertain sex differences in pain-related cerebral activation. Also inconsistent are findings regarding sex differences in responses to pharmacologic and non-pharmacologic pain treatments. The article concludes with a discussion of potential biopsychosocial mechanisms that may underlie sex differences in pain, and considerations for future research are discussed. Perspective This article reviews the recent literature regarding sex, gender, and pain. The growing body of evidence that has accumulated in the past 10 to 15 years continues to indicate substantial sex differences in clinical and experimental pain responses, and some evidence suggests that pain treatment responses may differ for women versus men. PMID:19411059
Thompson, Paul M.
2016-01-01
Sex differences in brain development and aging are important to identify, as they may help to understand risk factors and outcomes in brain disorders that are more prevalent in one sex compared with the other. Brain imaging techniques have advanced rapidly in recent years, yielding detailed structural and functional maps of the living brain. Even so, studies are often limited in sample size, and inconsistent findings emerge, one example being varying findings regarding sex differences in the size of the corpus callosum. More recently, large‐scale neuroimaging consortia such as the Enhancing Neuro Imaging Genetics through Meta Analysis Consortium have formed, pooling together expertise, data, and resources from hundreds of institutions around the world to ensure adequate power and reproducibility. These initiatives are helping us to better understand how brain structure is affected by development, disease, and potential modulators of these effects, including sex. This review highlights some established and disputed sex differences in brain structure across the life span, as well as pitfalls related to interpreting sex differences in health and disease. We also describe sex‐related findings from the ENIGMA consortium, and ongoing efforts to better understand sex differences in brain circuitry. © 2016 The Authors. Journal of Neuroscience Research Published by Wiley Periodicals, Inc. PMID:27870421
Febres, Jeniimarie; Rossi, Rita; Gaudiano, Brandon A; Miller, Ivan W
2011-07-01
Previous research suggests that depression and family functioning are related and that women and men may differ in how they respond to and cope with depression. Significantly less attention has been paid to whether sex moderates the relationship between family functioning and depression. In the current study, the relationship between depression severity and perceived family functioning, both generally and in specific areas, was examined in women and men (N = 117) hospitalized with major depression. The level of depression severity was not significantly different in men and in women. Correlations between depression severity and most domains of family functioning were significant and positive for men only. Furthermore, sex statistically moderated the associations between depression severity and family functioning in the areas of problem solving, communication, affective responsiveness, and behavior control. The implications for the assessment and treatment of family dysfunction in severely depressed patients are discussed.
Sex differences in amygdala activation during the perception of facial affect.
Killgore, W D; Yurgelun-Todd, D A
2001-08-08
The cognitive and affective systems of the cerebral cortex are often more lateralized in males than females, but it is unclear whether these differences extend to subcortical systems. We used fMRI to examine sex differences in lateralized amygdala activity during happy and fearful face perception. Amygdala activation differed for men and women depending on the valence of the expression. Overall, males were more lateralized than females, but the direction differed between valence conditions. Happy faces produced greater right than left amygdala activation for males but not females. Both sexes showed greater left amygdala activation for fearful faces. These findings suggest that the lateralization of affective function may extend beyond the cortex to subcortical regions such as the amygdala.
Jahanshad, Neda; Thompson, Paul M
2017-01-02
Sex differences in brain development and aging are important to identify, as they may help to understand risk factors and outcomes in brain disorders that are more prevalent in one sex compared with the other. Brain imaging techniques have advanced rapidly in recent years, yielding detailed structural and functional maps of the living brain. Even so, studies are often limited in sample size, and inconsistent findings emerge, one example being varying findings regarding sex differences in the size of the corpus callosum. More recently, large-scale neuroimaging consortia such as the Enhancing Neuro Imaging Genetics through Meta Analysis Consortium have formed, pooling together expertise, data, and resources from hundreds of institutions around the world to ensure adequate power and reproducibility. These initiatives are helping us to better understand how brain structure is affected by development, disease, and potential modulators of these effects, including sex. This review highlights some established and disputed sex differences in brain structure across the life span, as well as pitfalls related to interpreting sex differences in health and disease. We also describe sex-related findings from the ENIGMA consortium, and ongoing efforts to better understand sex differences in brain circuitry. © 2016 The Authors. Journal of Neuroscience Research Published by Wiley Periodicals, Inc. © 2016 The Authors. Journal of Neuroscience Research Published by Wiley Periodicals, Inc.
Determination of sex from the hyoid bone in a contemporary White population.
Logar, Ciara J; Peckmann, Tanya R; Meek, Susan; Walls, Stephen G
2016-04-01
Six discriminant functions, developed from an historic White population, were tested on a contemporary White population for determination of sex from the hyoid. One hundred and thirty four fused and unfused hyoids from a contemporary White population were used. Individuals ranged between 20 and 49 years old. Six historic White discriminant functions were applied to the fused and unfused hyoids of the pooled contemporary White population, i.e. all males and females and all age ranges combined. The overall accuracy rates were between 72.1% and 92.3%. Correct sex determination for contemporary White males ranged between 88.2% and 96.3%, while correct sex determination for contemporary White females ranged between 31.3% and 92.0%. Discriminant functions were created for the contemporary White population with overall mean accuracy rates between 67.0% and 93.0%. The multivariate discriminant function overall accuracy rates were between 89.0% and 93.0% and the univariate discriminant function overall accuracy rates were between 67.0% and 86.8%. The contemporary White population data were compared to other populations and showed significant differences between many of the variables measured. This study illustrated the need for population-specific and temporally-specific discriminant functions for determination of sex from the hyoid bone. Copyright © 2016 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.
Mechanical contributors to sex differences in idiopathic knee osteoarthritis
2012-01-01
The occurrence of knee osteoarthritis (OA) increases with age and is more common in women compared with men, especially after the age of 50 years. Recent work suggests that contact stress in the knee cartilage is a significant predictor of the risk for developing knee OA. Significant gaps in knowledge remain, however, as to how changes in musculoskeletal traits disturb the normal mechanical environment of the knee and contribute to sex differences in the initiation and progression of idiopathic knee OA. To illustrate this knowledge deficit, we summarize what is known about the influence of limb alignment, muscle function, and obesity on sex differences in knee OA. Observational data suggest that limb alignment can predict the development of radiographic signs of knee OA, potentially due to increased stresses and strains within the joint. However, these data do not indicate how limb alignment could contribute to sex differences in either the development or worsening of knee OA. Similarly, the strength of the knee extensor muscles is compromised in women who develop radiographic and symptomatic signs of knee OA, but the extent to which the decline in muscle function precedes the development of the disease is uncertain. Even less is known about how changes in muscle function might contribute to the worsening of knee OA. Conversely, obesity is a stronger predictor of developing knee OA symptoms in women than in men. The influence of obesity on developing knee OA symptoms is not associated with deviation in limb alignment, but BMI predicts the worsening of the symptoms only in individuals with neutral and valgus (knock-kneed) knees. It is more likely, however, that obesity modulates OA through a combination of systemic effects, particularly an increase in inflammatory cytokines, and mechanical factors within the joint. The absence of strong associations of these surrogate measures of the mechanical environment in the knee joint with sex differences in the development and progression of knee OA suggests that a more multifactorial and integrative approach in the study of this disease is needed. We identify gaps in knowledge related to mechanical influences on the sex differences in knee OA. PMID:23259740
Mechanical contributors to sex differences in idiopathic knee osteoarthritis.
Nicolella, Daniel P; O'Connor, Mary I; Enoka, Roger M; Boyan, Barbara D; Hart, David A; Resnick, Eileen; Berkley, Karen J; Sluka, Kathleen A; Kwoh, C Kent; Tosi, Laura L; Coutts, Richard D; Havill, Lorena M; Kohrt, Wendy M
2012-12-23
The occurrence of knee osteoarthritis (OA) increases with age and is more common in women compared with men, especially after the age of 50 years. Recent work suggests that contact stress in the knee cartilage is a significant predictor of the risk for developing knee OA. Significant gaps in knowledge remain, however, as to how changes in musculoskeletal traits disturb the normal mechanical environment of the knee and contribute to sex differences in the initiation and progression of idiopathic knee OA. To illustrate this knowledge deficit, we summarize what is known about the influence of limb alignment, muscle function, and obesity on sex differences in knee OA. Observational data suggest that limb alignment can predict the development of radiographic signs of knee OA, potentially due to increased stresses and strains within the joint. However, these data do not indicate how limb alignment could contribute to sex differences in either the development or worsening of knee OA. Similarly, the strength of the knee extensor muscles is compromised in women who develop radiographic and symptomatic signs of knee OA, but the extent to which the decline in muscle function precedes the development of the disease is uncertain. Even less is known about how changes in muscle function might contribute to the worsening of knee OA. Conversely, obesity is a stronger predictor of developing knee OA symptoms in women than in men. The influence of obesity on developing knee OA symptoms is not associated with deviation in limb alignment, but BMI predicts the worsening of the symptoms only in individuals with neutral and valgus (knock-kneed) knees. It is more likely, however, that obesity modulates OA through a combination of systemic effects, particularly an increase in inflammatory cytokines, and mechanical factors within the joint. The absence of strong associations of these surrogate measures of the mechanical environment in the knee joint with sex differences in the development and progression of knee OA suggests that a more multifactorial and integrative approach in the study of this disease is needed. We identify gaps in knowledge related to mechanical influences on the sex differences in knee OA.
PROCESS EXAMINATION OF EXECUTIVE FUNCTION IN ADHD: SEX AND SUBTYPE EFFECTS
Wodka, Ericka L.; Mostofsky, Stewart H.; Prahme, Cristine; Larson, Jennifer C. Gidley; Loftis, Christopher; Denckla, Martha B.; Mahone, E. Mark
2008-01-01
To examine effects of group (Attention-Deficit/Hyperactivity Disorder [ADHD] versus Typically Developing [TD]), sex, and ADHD subtype on “process/optional” measures of executive functioning, children (n = 123; 54 ADHD, 69 TD) aged 8−16 completed subtests from the D-KEFS. No group, sex, or ADHD subtype effects were found on optional measures from the Trail Making, Color–Word Interference, and Tower tests. A significant interaction was found for Verbal Fluency Total Repetition Errors; boys with Combined/Hyperactive-Impulsive (ADHD-C/HI) type ADHD performed better than ADHD-C/HI girls, whereas girls with Inattentive type ADHD (ADHD-I) performed better than ADHDI boys. Overall, children with ADHD did not differ from TD on most optional measures from the D-KEFS. When sex and ADHD subtype were considered, children with the subtype of ADHD less common for sex were at greater risk for poorer performance. PMID:18609314
The Trivers–Willard hypothesis: sex ratio or investment?
Veller, Carl; Haig, David; Nowak, Martin A.
2016-01-01
The Trivers–Willard hypothesis has commonly been considered to predict two things. First, that a mother in good condition should bias the sex ratio of her offspring towards males (if males exhibit greater variation in reproductive value). Second, that a mother in good condition should invest more per son than per daughter. These two predictions differ empirically, mechanistically and, as we demonstrate here, theoretically too. We construct a simple model of sex allocation that allows simultaneous analysis of both versions of the Trivers–Willard hypothesis. We show that the sex ratio version holds under very general conditions, being valid for a large class of male and female fitness functions. The investment version, on the other hand, is shown to hold only for a small subset of male and female fitness functions. Our results help to make sense of the observation that the sex ratio version is empirically more successful than the investment version. PMID:27170721
Rapid neo-sex chromosome evolution and incipient speciation in a major forest pest.
Bracewell, Ryan R; Bentz, Barbara J; Sullivan, Brian T; Good, Jeffrey M
2017-11-17
Genome evolution is predicted to be rapid following the establishment of new (neo) sex chromosomes, but it is not known if neo-sex chromosome evolution plays an important role in speciation. Here we combine extensive crossing experiments with population and functional genomic data to examine neo-XY chromosome evolution and incipient speciation in the mountain pine beetle. We find a broad continuum of intrinsic incompatibilities in hybrid males that increase in strength with geographic distance between reproductively isolated populations. This striking progression of reproductive isolation is coupled with extensive gene specialization, natural selection, and elevated genetic differentiation on both sex chromosomes. Closely related populations isolated by hybrid male sterility also show fixation of alternative neo-Y haplotypes that differ in structure and male-specific gene content. Our results suggest that neo-sex chromosome evolution can drive rapid functional divergence between closely related populations irrespective of ecological drivers of divergence.
Johnson, Michelle D; Dopierala, Justyna
2018-01-01
ABSTRACT DNA methylation is an important regulator of gene function. Fetal sex is associated with the risk of several specific pregnancy complications related to placental function. However, the association between fetal sex and placental DNA methylation remains poorly understood. We carried out whole-genome oxidative bisulfite sequencing in the placentas of two healthy female and two healthy male pregnancies generating an average genome depth of coverage of 25x. Most highly ranked differentially methylated regions (DMRs) were located on the X chromosome but we identified a 225 kb sex-specific DMR in the body of the CUB and Sushi Multiple Domains 1 (CSMD1) gene on chromosome 8. The sex-specific differential methylation pattern observed in this region was validated in additional placentas using in-solution target capture. In a new RNA-seq data set from 64 female and 67 male placentas, CSMD1 mRNA was 1.8-fold higher in male than in female placentas (P value = 8.5 × 10−7, Mann-Whitney test). Exon-level quantification of CSMD1 mRNA from these 131 placentas suggested a likely placenta-specific CSMD1 isoform not detected in the 21 somatic tissues analyzed. We show that the gene body of an autosomal gene, CSMD1, is differentially methylated in a sex- and placental-specific manner, displaying sex-specific differences in placental transcript abundance. PMID:29376485
Lack of sex effect on brain activity during a visuomotor response task: functional MR imaging study.
Mikhelashvili-Browner, Nina; Yousem, David M; Wu, Colin; Kraut, Michael A; Vaughan, Christina L; Oguz, Kader Karli; Calhoun, Vince D
2003-03-01
As more individuals are enrolled in clinical functional MR imaging (fMRI) studies, an understanding of how sex may influence fMRI-measured brain activation is critical. We used fixed- and random-effects models to study the influence of sex on fMRI patterns of brain activation during a simple visuomotor reaction time task in the group of 26 age-matched men and women. We evaluated the right visual, left visual, left primary motor, left supplementary motor, and left anterior cingulate areas. Volumes of activations did not significantly differ between the groups in any defined regions. Analysis of variance failed to show any significant correlations between sex and volumes of brain activation in any location studied. Mean percentage signal-intensity changes for all locations were similar between men and women. A two-way t test of brain activation in men and women, performed as a part of random-effects modeling, showed no significant difference at any site. Our results suggest that sex seems to have little influence on fMRI brain activation when we compared performance on the simple reaction-time task. The need to control for sex effects is not critical in the analysis of this task with fMRI.
Sex-Dependent Effects of Developmental Lead Exposure on the Brain.
Singh, Garima; Singh, Vikrant; Sobolewski, Marissa; Cory-Slechta, Deborah A; Schneider, Jay S
2018-01-01
The role of sex as an effect modifier of developmental lead (Pb) exposure has until recently received little attention. Lead exposure in early life can affect brain development with persisting influences on cognitive and behavioral functioning, as well as, elevated risks for developing a variety of diseases and disorders in later life. Although both sexes are affected by Pb exposure, the incidence, manifestation, and severity of outcomes appears to differ in males and females. Results from epidemiologic and animal studies indicate significant effect modification by sex, however, the results are not consistent across studies. Unfortunately, only a limited number of human epidemiological studies have included both sexes in independent outcome analyses limiting our ability to draw definitive conclusions regarding sex-differentiated outcomes. Additionally, due to various methodological differences across studies, there is still not a good mechanistic understanding of the molecular effects of lead on the brain and the factors that influence differential responses to Pb based on sex. In this review, focused on prenatal and postnatal Pb exposures in humans and animal models, we discuss current literature supporting sex differences in outcomes in response to Pb exposure and explore some of the ideas regarding potential molecular mechanisms that may contribute to sex-related differences in outcomes from developmental Pb exposure. The sex-dependent variability in outcomes from developmental Pb exposure may arise from a combination of complex factors, including, but not limited to, intrinsic sex-specific molecular/genetic mechanisms and external risk factors including sex-specific responses to environmental stressors which may act through shared epigenetic pathways to influence the genome and behavioral output.
Sex-Dependent Effects of Developmental Lead Exposure on the Brain
Singh, Garima; Singh, Vikrant; Sobolewski, Marissa; Cory-Slechta, Deborah A.; Schneider, Jay S.
2018-01-01
The role of sex as an effect modifier of developmental lead (Pb) exposure has until recently received little attention. Lead exposure in early life can affect brain development with persisting influences on cognitive and behavioral functioning, as well as, elevated risks for developing a variety of diseases and disorders in later life. Although both sexes are affected by Pb exposure, the incidence, manifestation, and severity of outcomes appears to differ in males and females. Results from epidemiologic and animal studies indicate significant effect modification by sex, however, the results are not consistent across studies. Unfortunately, only a limited number of human epidemiological studies have included both sexes in independent outcome analyses limiting our ability to draw definitive conclusions regarding sex-differentiated outcomes. Additionally, due to various methodological differences across studies, there is still not a good mechanistic understanding of the molecular effects of lead on the brain and the factors that influence differential responses to Pb based on sex. In this review, focused on prenatal and postnatal Pb exposures in humans and animal models, we discuss current literature supporting sex differences in outcomes in response to Pb exposure and explore some of the ideas regarding potential molecular mechanisms that may contribute to sex-related differences in outcomes from developmental Pb exposure. The sex-dependent variability in outcomes from developmental Pb exposure may arise from a combination of complex factors, including, but not limited to, intrinsic sex-specific molecular/genetic mechanisms and external risk factors including sex-specific responses to environmental stressors which may act through shared epigenetic pathways to influence the genome and behavioral output. PMID:29662502
Deadlines in space: Selective effects of coordinate spatial processing in multitasking.
Todorov, Ivo; Del Missier, Fabio; Konke, Linn Andersson; Mäntylä, Timo
2015-11-01
Many everyday activities require coordination and monitoring of multiple deadlines. One way to handle these temporal demands might be to represent future goals and deadlines as a pattern of spatial relations. We examined the hypothesis that spatial ability, in addition to executive functioning, contributes to individual differences in multitasking. In two studies, participants completed a multitasking session in which they monitored four digital clocks running at different rates. In Study 1, we found that individual differences in spatial ability and executive functions were independent predictors of multiple-task performance. In Study 2, we found that individual differences in specific spatial abilities were selectively related to multiple-task performance, as only coordinate spatial processing, but not categorical, predicted multitasking, even beyond executive functioning and numeracy. In both studies, males outperformed females in spatial ability and multitasking and in Study 2 these sex differences generalized to a simulation of everyday multitasking. Menstrual changes moderated the effects on multitasking, in that sex differences in coordinate spatial processing and multitasking were observed between males and females in the luteal phase of the menstrual cycle, but not between males and females at menses. Overall, these findings suggest that multiple-task performance reflects independent contributions of spatial ability and executive functioning. Furthermore, our results support the distinction of categorical versus coordinate spatial processing, and suggest that these two basic relational processes are selectively affected by female sex hormones and differentially effective in transforming and handling temporal patterns as spatial relations in the context of multitasking.
Sex steroid signaling: implications for lung diseases.
Sathish, Venkatachalem; Martin, Yvette N; Prakash, Y S
2015-06-01
There is increasing recognition that sex hormones (estrogen, progesterone, and testosterone) have biological and pathophysiological actions in peripheral, non-reproductive organs, including the lung. Clinically, sex differences in the incidence, morbidity and mortality of lung diseases such as asthma, chronic obstructive pulmonary disease (COPD), pulmonary fibrosis, lung cancer and pulmonary hypertension have been noted, although intrinsic sex differences vs. the roles of sex steroids are still not well-understood. Accordingly, it becomes important to ask the following questions: 1) Which sex steroids are involved? 2) How do they affect different components of the lung under normal circumstances? 3) How does sex steroid signaling change in or contribute to lung disease, and in this regard, are sex steroids detrimental or beneficial? As our understanding of sex steroid signaling in the lung improves, it is important to consider whether such information can be used to develop new therapeutic strategies to target lung diseases, perhaps in both sexes or in a sex-specific manner. In this review, we focus on the basics of sex steroid signaling, and the current state of knowledge regarding how they influence structure and function of specific lung components across the life span and in the context of some important lung diseases. We then summarize the potential for sex steroids as useful biomarkers and therapeutic targets in these lung diseases as a basis for future translational research in the area of gender and individualized medicine. Copyright © 2015 Elsevier Inc. All rights reserved.
Claxton, Amy; Baker, Laura D.; Wilkinson, Charles W.; Trittschuh, Emily H.; Chapmana, Darla; Watson, G. Stennis; Cholerton, Brenna; Plymate, Stephen R.; Arbuckle, Matthew; Craft, Suzanne
2014-01-01
A previous clinical trial demonstrated that four months of treatment with intranasal insulin improves cognition and function for patients with Alzheimer’s disease (AD) or mild cognitive impairment (MCI), but prior studies suggest that response to insulin treatment may differ by sex and ApoE ε4 carriage. Thus, responder analyses using repeated measures analysis of covariance were completed on the trial’s 104 participants with MCI or AD who received either placebo or 20 or 40 IU of insulin for 4 months, administered by a nasal delivery device. Results indicate that men and women with memory impairment responded differently to intranasal insulin treatment. On delayed story memory, men and women showed cognitive improvement when taking 20 IU of intranasal insulin, but only men showed cognitive improvement for the 40 IU dose. The sex difference was most apparent for ApoE ε4 negative individuals. For the 40 IU dose, ApoE ε4 negative men improved while ApoE ε4 negative women worsened. Their ApoE ε4 positive counterparts remained cognitively stable. This sex effect was not detected in functional measures. However, functional abilities were relatively preserved for women on either dose of intranasal insulin compared with men. Unlike previous studies with young adults, neither men nor women taking intranasal insulin exhibited a significant change in weight over 4 months of treatment. PMID:23507773
Neurobehavioral Deficits Consistent Across Age and Sex in Youth with Prenatal Alcohol Exposure
Panczakiewicz, Amy L.; Glass, Leila; Coles, Claire D.; Kable, Julie A.; Sowell, Elizabeth R.; Wozniak, Jeffrey R.; Jones, Kenneth Lyons; Riley, Edward P.; Mattson, Sarah N.
2016-01-01
Background Neurobehavioral consequences of heavy prenatal alcohol exposure are well documented, however the role of age or sex in these effects has not been studied. The current study examined the effects of prenatal alcohol exposure, sex, and age on neurobehavioral functioning in children. Methods Subjects were 407 youth with prenatal alcohol exposure (n=192) and controls (n=215). Two age groups [child (5–7y) or adolescent (10–16y)] and both sexes were included. All subjects completed standardized neuropsychological testing and caregivers completed parent-report measures of psychopathology and adaptive behavior. Neuropsychological functioning, psychopathology, and adaptive behavior were analyzed with separate 2 (exposure history) × 2 (sex) × 2 (age) MANOVAs. Significant effects were followed by univariate analyses. Results No three-way or two-way interactions were significant. The main effect of group was significant in all three MANOVAs, with the control group performing better than the alcohol-exposed group on all measures. The main effect of age was significant for neuropsychological performance and adaptive functioning across exposure groups with younger children performing better than older children on three measures (language, communication, socialization). Older children performed better than younger children on a different language measure. The main effect of sex was significant for neuropsychological performance and psychopathology; across exposure groups, males had stronger language and visual-spatial scores and fewer somatic complaints than females. Conclusion Prenatal alcohol exposure resulted in impaired neuropsychological and behavioral functioning. Although adolescents with prenatal alcohol exposure may perform more poorly than younger exposed children, the same was true for non-exposed children. Thus, these cross-sectional data indicate that the developmental trajectory for neuropsychological and behavioral performance is not altered by prenatal alcohol exposure, but rather, deficits are consistent across the two age groups tested. Similarly, observed sex differences on specific measures were consistent across the groups and do not support sexually dimorphic effects in these domains. PMID:27430360
Beckers, Oliver M; Kijimoto, Teiya; Moczek, Armin P
2017-10-01
Despite sharing nearly the same genome, individuals within the same species can vary drastically in both morphology and behaviour as a function of developmental stage, sex or developmental plasticity. Thus, regulatory processes must exist that enable the stage-, sex- or environment-specific expression of traits and their integration during ontogeny, yet exactly how trait complexes are co-regulated and integrated is poorly understood. In this study, we explore the developmental genetic basis of the regulation and integration of environment-dependent sexual dimorphism in behaviour and morphology in the horn-polyphenic dung beetle Onthophagus taurus through the experimental manipulation of the transcription factor doublesex (dsx). The gene dsx plays a profound role in the developmental regulation of morphological differences between sexes as well as alternative male morphs by inhibiting horn formation in females but enabling nutrition-responsive horn growth in males. Specifically, we investigated whether experimental downregulation of dsx expression affects male and female aggressive and courtship behaviours in two social contexts: interactions between individuals of the same sex and interactions between males and females. We find that dsx downregulation significantly alters aggressiveness in both males and females, yet does so differently for both sexes as a function of social context: dsx RNAi males exhibited elevated aggression towards males but showed reduced aggression towards females, whereas dsx RNAi females became more aggressive towards males, while their aggressiveness towards other females was unaffected. Moreover, we document unexpectedly high levels of female aggression independent of dsx treatment in both wild-type and control-injected individuals. Lastly, we found no effects of dsx RNAi on courtship and mating behaviours. We discuss the role of dsx in the regulation of sex-specific and plastic behaviours, the unexpectedly high levels of aggression of hornless dsx RNAi males in relation to the well-established description of the hornless sneaker phenotype and the potential ecological function of high female aggression.
Sex differences in the circadian regulation of sleep and waking cognition in humans.
Santhi, Nayantara; Lazar, Alpar S; McCabe, Patrick J; Lo, June C; Groeger, John A; Dijk, Derk-Jan
2016-05-10
The sleep-wake cycle and circadian rhythmicity both contribute to brain function, but whether this contribution differs between men and women and how it varies across cognitive domains and subjective dimensions has not been established. We examined the circadian and sleep-wake-dependent regulation of cognition in 16 men and 18 women in a forced desynchrony protocol and quantified the separate contributions of circadian phase, prior sleep, and elapsed time awake on cognition and sleep. The largest circadian effects were observed for reported sleepiness, mood, and reported effort; the effects on working memory and temporal processing were smaller. Although these effects were seen in both men and women, there were quantitative differences. The amplitude of the circadian modulation was larger in women in 11 of 39 performance measures so that their performance was more impaired in the early morning hours. Principal components analysis of the performance measures yielded three factors, accuracy, effort, and speed, which reflect core performance characteristics in a range of cognitive tasks and therefore are likely to be important for everyday performance. The largest circadian modulation was observed for effort, whereas accuracy exhibited the largest sex difference in circadian modulation. The sex differences in the circadian modulation of cognition could not be explained by sex differences in the circadian amplitude of plasma melatonin and electroencephalographic slow-wave activity. These data establish the impact of circadian rhythmicity and sex on waking cognition and have implications for understanding the regulation of brain function, cognition, and affect in shift-work, jetlag, and aging.
Sex differences in the circadian regulation of sleep and waking cognition in humans
Santhi, Nayantara; Lazar, Alpar S.; McCabe, Patrick J.; Lo, June C.; Groeger, John A.; Dijk, Derk-Jan
2016-01-01
The sleep–wake cycle and circadian rhythmicity both contribute to brain function, but whether this contribution differs between men and women and how it varies across cognitive domains and subjective dimensions has not been established. We examined the circadian and sleep–wake-dependent regulation of cognition in 16 men and 18 women in a forced desynchrony protocol and quantified the separate contributions of circadian phase, prior sleep, and elapsed time awake on cognition and sleep. The largest circadian effects were observed for reported sleepiness, mood, and reported effort; the effects on working memory and temporal processing were smaller. Although these effects were seen in both men and women, there were quantitative differences. The amplitude of the circadian modulation was larger in women in 11 of 39 performance measures so that their performance was more impaired in the early morning hours. Principal components analysis of the performance measures yielded three factors, accuracy, effort, and speed, which reflect core performance characteristics in a range of cognitive tasks and therefore are likely to be important for everyday performance. The largest circadian modulation was observed for effort, whereas accuracy exhibited the largest sex difference in circadian modulation. The sex differences in the circadian modulation of cognition could not be explained by sex differences in the circadian amplitude of plasma melatonin and electroencephalographic slow-wave activity. These data establish the impact of circadian rhythmicity and sex on waking cognition and have implications for understanding the regulation of brain function, cognition, and affect in shift-work, jetlag, and aging. PMID:27091961
Koops, Kathelijne; Furuichi, Takeshi; Hashimoto, Chie; van Schaik, Carel P
2015-01-01
Sex differences in immatures predict behavioural differences in adulthood in many mammal species. Because most studies have focused on sex differences in social interactions, little is known about possible sex differences in 'preparation' for adult life with regards to tool use skills. We investigated sex and age differences in object manipulation in immature apes. Chimpanzees use a variety of tools across numerous contexts, whereas bonobos use few tools and none in foraging. In both species, a female bias in adult tool use has been reported. We studied object manipulation in immature chimpanzees at Kalinzu (Uganda) and bonobos at Wamba (Democratic Republic of Congo). We tested predictions of the 'preparation for tool use' hypothesis. We confirmed that chimpanzees showed higher rates and more diverse types of object manipulation than bonobos. Against expectation, male chimpanzees showed higher object manipulation rates than females, whereas in bonobos no sex difference was found. However, object manipulation by male chimpanzees was play-dominated, whereas manipulation types of female chimpanzees were more diverse (e.g., bite, break, carry). Manipulation by young immatures of both species was similarly dominated by play, but only in chimpanzees did it become more diverse with age. Moreover, in chimpanzees, object types became more tool-like (i.e., sticks) with age, further suggesting preparation for tool use in adulthood. The male bias in object manipulation in immature chimpanzees, along with the late onset of tool-like object manipulation, indicates that not all (early) object manipulation (i.e., object play) in immatures prepares for subsistence tool use. Instead, given the similarity with gender differences in human children, object play may also function in motor skill practice for male-specific behaviours (e.g., dominance displays). In conclusion, even though immature behaviours almost certainly reflect preparation for adult roles, more detailed future work is needed to disentangle possible functions of object manipulation during development.
Koops, Kathelijne; Furuichi, Takeshi; Hashimoto, Chie; van Schaik, Carel P.
2015-01-01
Sex differences in immatures predict behavioural differences in adulthood in many mammal species. Because most studies have focused on sex differences in social interactions, little is known about possible sex differences in ‘preparation’ for adult life with regards to tool use skills. We investigated sex and age differences in object manipulation in immature apes. Chimpanzees use a variety of tools across numerous contexts, whereas bonobos use few tools and none in foraging. In both species, a female bias in adult tool use has been reported. We studied object manipulation in immature chimpanzees at Kalinzu (Uganda) and bonobos at Wamba (Democratic Republic of Congo). We tested predictions of the ‘preparation for tool use’ hypothesis. We confirmed that chimpanzees showed higher rates and more diverse types of object manipulation than bonobos. Against expectation, male chimpanzees showed higher object manipulation rates than females, whereas in bonobos no sex difference was found. However, object manipulation by male chimpanzees was play-dominated, whereas manipulation types of female chimpanzees were more diverse (e.g., bite, break, carry). Manipulation by young immatures of both species was similarly dominated by play, but only in chimpanzees did it become more diverse with age. Moreover, in chimpanzees, object types became more tool-like (i.e., sticks) with age, further suggesting preparation for tool use in adulthood. The male bias in object manipulation in immature chimpanzees, along with the late onset of tool-like object manipulation, indicates that not all (early) object manipulation (i.e., object play) in immatures prepares for subsistence tool use. Instead, given the similarity with gender differences in human children, object play may also function in motor skill practice for male-specific behaviours (e.g., dominance displays). In conclusion, even though immature behaviours almost certainly reflect preparation for adult roles, more detailed future work is needed to disentangle possible functions of object manipulation during development. PMID:26444011
Aggen, S. H.; Neale, M. C.; Røysamb, E.; Reichborn-Kjennerud, T.; Kendler, K. S.
2009-01-01
Background Despite its importance as a paradigmatic personality disorder, little is known about the measurement invariance of the DSM-IV borderline personality disorder (BPD) criteria ; that is, whether the criteria assess the disorder equivalently across different groups. Method BPD criteria were evaluated at interview in 2794 young adult Norwegian twins. Analyses, based on item-response modeling, were conducted to test for differential age and sex moderation of the individual BPD criteria characteristics given factor-level covariate effects. Results Confirmatory factor analytic results supported a unidimensional structure for the nine BPD criteria. Compared to males, females had a higher BPD factor mean, larger factor variance and there was a significant age by sex interaction on the factor mean. Strong differential sex and age by sex interaction effects were found for the ‘ impulsivity ’ criterion factor loading and threshold. Impulsivity related to the BPD factor poorly in young females but improved significantly in older females. Males reported more impulsivity compared to females and this difference increased with age. The ‘ affective instability ’ threshold was also moderated, with males reporting less than expected. Conclusions The results suggest the DSM-IV BPD ‘ impulsivity ’ and ‘ affective instability ’ criteria function differentially with respect to age and sex, with impulsivity being especially problematic. If verified, these findings have important implications for the interpretation of prior research with these criteria. These non-invariant age and sex effects may be identifying criteria-level expression features relevant to BPD nosology and etiology. Criterion functioning assessed using modern psychometric methods should be considered in the development of DSM-V. PMID:19400977
Sex differences in olfactory-induced neural activation of the amygdala.
Kikusui, Takefumi; Kajita, Mayu; Otsuka, Natsumi; Hattori, Tatsuya; Kumazawa, Kanako; Watarai, Akiyuki; Nagasawa, Miho; Inutsuka, Ayumu; Yamanaka, Akihiro; Matsuo, Naoki; Covington, Herbert E; Mogi, Kazutaka
2018-07-02
Olfactory signals, including the scent of urine, are thought to be processed by specific brain regions, such as the medial amygdala (Me), and regulate sexual behavior in a sex-dependent manner. We aimed to reveal the sex-specific neural circuit from the accessory olfactory bulb (AOB) to Me by using a transgenic mouse. We quantified the long-lasting green fluorescent protein (GFP) expression profile, which was controlled by the c-fos promotor in a sex-dependent manner by the scent of urine. Female urine predominantly activated neurons of the posterodorsal medial amygdala (MePD) in male mice and the posteroventral medial amygdala (MePV) in female mice. Male urine, in contrast, generated the opposite pattern of activation in the Me. Secondary, the selective artificial activation of these circuits was used to examine their specific behavioral function, by using a dual Cre-loxP viral infection. AAV-hSyn-FLEX-hM3Dq-EGFP-the designer receptor exclusively activated by a designer drug-was infused into the AOB after infection with trans-synaptic AAV(DJ)-CMV-mCherry-2A-Cre-TTC into either the MePD or the MePV. Double virus-transfected mice were injected with hM 3 Dq activator and their sexual behavior was monitored. However, selective activation of sex-dependent circuits, i.e., the AOB-MePD or AOB-MePV, did not significantly alter mounting or attack behavior in male mice. There were clear sex differences in the pheromone conveying circuits in the AOB-Me of mice. The sex-dependent functional activation of the Me, however, no effect on behavior. This suggests that a diverse number of nuclei and brain areas are likely to function in concert to successfully facilitate sexual and aggressive behaviors. Copyright © 2017 Elsevier B.V. All rights reserved.
Cameron, Skye F; Wheatley, Rebecca; Wilson, Robbie S
2018-07-01
Studies of sexual selection primarily focus on morphological traits such as body size and secondary trait dimorphism, with less attention been given to the functional differences between the sexes and even more so their thermal performance capacities. Each sex may benefit from possessing different thermal performance capacities that would allow them to maximise their fitness relative to their different reproductive roles; especially when performances are closely related to reproductive success. Here, we examine sexual divergence in thermal sensitivities of performance across three populations of the Asian house gecko (Hemidactylus frenatus) over an extensive latitudinal cline. Using analyses of the thermal sensitivity of routine activity, bite force and sprint speed, we explored whether: (i) males and females differed in their optimal temperatures for performance, (ii) the sexes differed in their thermal sensitivities of performance, and (iii) the degree of sexual divergence in thermal sensitivity varied among the populations. Because male H. frenatus are highly aggressive and frequently engage in combat to gain territories and mating opportunities, we expected males would be active over a wider range of temperatures than females and this would favour broad thermal sensitivity curves for males. In addition, we expected a greater divergence between the sexes in thermal sensitivities for the temperate populations that experience greater daily and seasonal thermal variation. We found that males were more active, and had greater bite forces and faster sprint speeds than females, independent of body size. In addition, we found differences between the sexes in thermal sensitivities for the tropical population; female H. frenatus were less active and possessed lower sprint speeds at higher temperatures than males. Although H. frenatus from the most variable thermal environments also displayed the broadest thermal performance range, it was the more stable tropical population that exhibited the greatest divergence between the sexes in thermal sensitivity of performance. The divergence in thermal physiology that we detected between the sexes of H. frenatus is consistent with the idea that males will derive mating and territorial advantages for maintaining function over a broader range of temperatures.
Effects of sex chromosome aneuploidies on brain development: evidence from neuroimaging studies.
Lenroot, Rhoshel K; Lee, Nancy Raitano; Giedd, Jay N
2009-01-01
Variation in the number of sex chromosomes is a relatively common genetic condition, affecting as many as 1/400 individuals. The sex chromosome aneuploidies (SCAs) are associated with characteristic behavioral and cognitive phenotypes, although the degree to which specific individuals are affected can fall within a wide range. Understanding the effects of different dosages of sex chromosome genes on brain development may help to understand the basis for functional differences in affected individuals. It may also be informative regarding how sex chromosomes contribute to typical sexual differentiation. Studies of 47,XXY males make up the bulk of the current literature of neuroimaging studies in individuals with supernumerary sex chromosomes, with a few small studies or case reports of the other SCAs. Findings in 47,XXY males typically include decreased gray and white matter volumes, with most pronounced effects in the frontal and temporal lobes. Functional studies have shown evidence of decreased lateralization. Although the hypogonadism typically found in 47,XXY males may contribute to the decreased brain volume, the observation that 47,XXX females also show decreased brain volume in the presence of normal pubertal maturation suggests a possible direct dosage effect of X chromosome genes. Additional X chromosomes, such as in 49,XXXXY males, are associated with more markedly decreased brain volume and increased incidence of white matter hyperintensities. The limited data regarding effects of having two Y chromosomes (47,XYY) do not find significant differences in brain volume, although there are some reports of increased head size.
Effects of Sex Chromosome Aneuploidies on Brain Development: Evidence From Neuroimaging Studies
Lenroot, Rhoshel K.; Lee, Nancy Raitano; Giedd, Jay N.
2010-01-01
Variation in the number of sex chromosomes is a relatively common genetic condition, affecting as many as 1/400 individuals. The sex chromosome aneuploidies (SCAs) are associated with characteristic behavioral and cognitive phenotypes, although the degree to which specific individuals are affected can fall within a wide range. Understanding the effects of different dosages of sex chromosome genes on brain development may help to understand the basis for functional differences in affected individuals. It may also be informative regarding how sex chromosomes contribute to typical sexual differentiation. Studies of 47,XXY males make up the bulk of the current literature of neuroimaging studies in individuals with supernumerary sex chromosomes, with a few small studies or case reports of the other SCAs. Findings in 47,XXY males typically include decreased gray and white matter volumes, with most pronounced effects in the frontal and temporal lobes. Functional studies have shown evidence of decreased lateralization. Although the hypogonadism typically found in 47,XXY males may contribute to the decreased brain volume, the observation that 47,XXX females also show decreased brain volume in the presence of normal pubertal maturation suggests a possible direct dosage effect of X chromosome genes. Additional X chromosomes, such as in 49,XXXXY males, are associated with more markedly decreased brain volume and increased incidence of white matter hyperintensities. The limited data regarding effects of having two Y chromosomes (47,XYY) do not find significant differences in brain volume, although there are some reports of increased head size. PMID:20014372
Sex differences in the neural circuit that mediates female sexual receptivity
Flanagan-Cato, Loretta M.
2011-01-01
Female sexual behavior in rodents, typified by the lordosis posture, is hormone-dependent and sex-specific. Ovarian hormones control this behavior via receptors in the hypothalamic ventromedial nucleus (VMH). This review considers the sex differences in the morphology, neurochemistry and neural circuitry of the VMH to gain insights into the mechanisms that control lordosis. The VMH is larger in males compared with females, due to more synaptic connections. Another sex difference is the responsiveness to estradiol, with males exhibiting muted, and in some cases reverse, effects compared with females. The lack of lordosis in males may be explained by differences in synaptic organization or estrogen responsiveness, or both, in the VMH. However, given that damage to other brain regions unmasks lordosis behavior in males, a male-typical VMH is unlikely the main factor that prevents lordosis. In females, key questions remain regarding the mechanisms whereby ovarian hormones modulate VMH function to promote lordosis. PMID:21338620
Rind, Bruce
2017-07-17
This study used an important data set to examine long-term adjustment and functioning in men, who as adolescents had sexual experiences with men. The data came from the National Health and Social Life Survey, which used a national probability sample (Laumann, Gagnon, Michael, & Michaels, 1994). Three perspectives were considered, which offered different predictions. From the "child sexual abuse" (CSA) paradigm, which dominates clinical, legal, and lay views, expected was robust evidence for poorer adjustment, given that intense harm is assumed to be intrinsic. From the "mainstream psychological" perspective, derived from the CSA paradigm but more scientifically based, poorer adjustment was also expected, but with less magnitude, given that minor-adult sex is seen as posing a serious risk of harm, which may not universally apply. From the "relevant-empirical" perspective, which infers response to male adolescent-adult same-sex sex from relevant prior empirical research (as opposed to clinical cases or the female experience), expected was little or no evidence for poorer adjustment. Results supported the relevant-empirical perspective. Compared to several control groups (i.e., men whose first postpubertal same-sex sex was as men with other men; men with no postpubertal same-sex sexual experience or child-adult sex), men whose first postpubertal same-sex sex was as adolescents with men were just as well adjusted in terms of health, happiness, sexual functioning, and educational and career achievement. Results are discussed in relation to cultural influences, other cultures, and comparative data from primates.
Effects of Brief Cognitive-Behavioral Therapy on Recidivism among Sex and Non-Sex Offenders.
ERIC Educational Resources Information Center
Valliant, Paul M.; Sloss, Bryan K.; Raven-Brooks, Lynne
1997-01-01
Compared incarcerated recidivists and nonrecidivists enrolled in a cognitive behavioral therapy program to judge treatment effectiveness as a function of offense. Results indicate that recidivism was a significant predictor of change in pre- and postindirect hostility measures. Significant personality differences emerged for the offender…
Sex differences and the effects of ovariectomy on the β-adrenergic contractile response
McIntosh, Victoria J.; Chandrasekera, P. Charukeshi
2011-01-01
The presence of sex differences in myocardial β-adrenergic responsiveness is controversial, and limited studies have addressed the mechanism underlying these differences. Studies were performed using isolated perfused hearts from male, intact female and ovariectomized female mice to investigate sex differences and the effects of ovarian hormone withdrawal on β-adrenergic receptor function. Female hearts exhibited blunted contractile responses to the β-adrenergic receptor agonist isoproterenol (ISO) compared with males but not ovariectomized females. There were no sex differences in β1-adrenergic receptor gene or protein expression. To investigate the role of adenylyl cyclase, phosphodiesterase, and the cAMP-signaling cascade in generating sex differences in the β-adrenergic contractile response, dose-response studies were performed in isolated perfused male and female hearts using forskolin, 3-isobutyl-1-methylxanthine (IBMX), and 8-(4-chlorophenylthio)adenosine 3′,5′-cyclic monophosphate (CPT-cAMP). Males showed a modestly enhanced contractile response to forskolin at 300 nM and 5 μM compared with females, but there were no sex differences in the response to IBMX or CPT-cAMP. The role of the A1 adenosine receptor (A1AR) in antagonizing the β-adrenergic contractile response was investigated using both the A1AR agonist 2-chloro-N6-cyclopentyl-adenosine and A1AR knockout (KO) mice. Intact females showed an enhanced A1AR anti-adrenergic effect compared with males and ovariectomized females. The β-adrenergic contractile response was potentiated in both male and female A1ARKO hearts, with sex differences no longer present above 1 nM ISO. The β-adrenergic contractile response is greater in male hearts than females, and minor differences in the action of adenylyl cyclase or the A1AR may contribute to these sex differences. PMID:21685268
Neuropsychology of domestic violence: a comparative preliminary study of executive functioning.
Becerra-García, Juan Antonio
2015-01-01
In neuropsychological studies of executive functioning in domestic violence offenders, the different investigations conducted have only studied differences within this group or in relation to control groups of non-offenders. To minimize the limitations in relation to comparison groups, the purpose of this study was to compare executive functioning in domestic violence offenders in relation to different groups of offenders (i.e. sexual, violent and non-violent) and a control group of non-offenders, with all groups matched on socio-demographic and clinical characteristics. Executive functioning was tested of all participants with the Trail Making Test (direct and derived scores). Compared with the control group, the domestic violence offenders and sex offenders exhibited the poorest performance on the Trail Making Test part B (time) and on the B-A derived index; whereas, the violent offenders group (i.e. convicted of assault, wounding, homicide etc.) showed a high number of errors in part B. These findings suggest that domestic violence offenders exhibit similar performance on the TMT as sex offenders, where both have poorer cognitive flexibility and executive control. Other violent offenders exhibited different patterns of difficulty on this test (e.g. more impulsivity responses). Executive functioning may be a central psychological process that could help explain the interrelations between domestic and sexual aggression, and could be a relevant construct for common treatment of domestic batterers and sex offenders. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.
Sex and vision II: color appearance of monochromatic lights.
Abramov, Israel; Gordon, James; Feldman, Olga; Chavarga, Alla
2012-09-04
Because cerebral cortex has a very large number of testosterone receptors, we examined the possible sex differences in color appearance of monochromatic lights across the visible spectrum. There is a history of men and women perceiving color differently. However, all of these studies deal with higher cognitive functions which may be culture-biased. We study basic visual functions, such as color appearance, without reference to any objects. We present here a detailed analysis of sex differences in primary chromatic sensations. We tested large groups of young adults with normal vision, including spatial and temporal resolution, and stereopsis. Based on standard color-screening and anomaloscope data, we excluded all color-deficient observers. Stimuli were equi-luminant monochromatic lights across the spectrum. They were foveally-viewed flashes presented against a dark background. The elicited sensations were measured using magnitude estimation of hue and saturation. When the only permitted hue terms are red (R) yellow (Y), green (G), blue (B), alone or in combination, such hue descriptions are language-independent and the hue and saturation values can be used to derive a wide range of color-discrimination functions. There were relatively small but clear and significant, differences between males and females in the hue sensations elicited by almost the entire spectrum. Generally, males required a slightly longer wavelength to experience the same hue as did females. The spectral loci of the unique hues are not correlated with anomaloscope matches; these matches are directly determined by the spectral sensitivities of L- and M-cones (genes for these cones are on the X-chromosomes). Nor are there correlations between loci of pairs of unique hues (R, Y, G, B). Wavelength-discrimination functions derived from the scaling data show that males have a broader range of poorer discrimination in the middle of the spectrum. The precise values for all the data depend on whether Newtonian or Maxwellian optics were used, but the sex differences were the same for both optical systems. As with our associated paper on spatio-temporal vision, there are marked sex differences in color vision. The color-appearances we measured are determined by inputs from thalamic neurons (LGN) to individual neurons in primary visual cortex. This convergence from LGN to cortex is guided by the cortex during embryogenesis. We hypothesize that testosterone plays a major role, somehow leading to different connectivities for males and females: color appearance requires a re-combination and re-weighting of neuronal inputs from the LGN to the cortex, which, as we show, depends on the sex of the participant.
The Human Pelvis: Variation in structure and function during gait
Lewis, Cara L.; Laudicina, Natalie M.; Khuu, Anne; Loverro, Kari L.
2017-01-01
The shift to habitual bipedalism 4–6 million years ago in the hominin lineage created a morphologically and functionally different human pelvis compared to our closest living relatives, the chimpanzees. Evolutionary changes to the shape of the pelvis were necessary for the transition to habitual bipedalism in humans. These changes in the bony anatomy resulted in an altered role of muscle function, influencing bipedal gait. Additionally, there are normal sex-specific variations in the pelvis as well as abnormal variations in the acetabulum. During gait, the pelvis moves in the three planes to produce smooth and efficient motion. Subtle sex-specific differences in these motions may facilitate economical gait despite differences in pelvic structure. The motions of the pelvis and hip may also be altered in the presence of abnormal acetabular structure, especially with acetabular dysplasia. PMID:28297184
Salehi, Mehraveh; Karbasi, Amin; Shen, Xilin; Scheinost, Dustin; Constable, R Todd
2018-04-15
Recent work with functional connectivity data has led to significant progress in understanding the functional organization of the brain. While the majority of the literature has focused on group-level parcellation approaches, there is ample evidence that the brain varies in both structure and function across individuals. In this work, we introduce a parcellation technique that incorporates delineation of functional networks both at the individual- and group-level. The proposed technique deploys the notion of "submodularity" to jointly parcellate the cerebral cortex while establishing an inclusive correspondence between the individualized functional networks. Using this parcellation technique, we successfully established a cross-validated predictive model that predicts individuals' sex, solely based on the parcellation schemes (i.e. the node-to-network assignment vectors). The sex prediction finding illustrates that individualized parcellation of functional networks can reveal subgroups in a population and suggests that the use of a global network parcellation may overlook fundamental differences in network organization. This is a particularly important point to consider in studies comparing patients versus controls or even patient subgroups. Network organization may differ between individuals and global configurations should not be assumed. This approach to the individualized study of functional organization in the brain has many implications for both neuroscience and clinical applications. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.
ERIC Educational Resources Information Center
Hartley, Sigan L.; Sikora, Darryn M.
2009-01-01
Little is known about the female presentation of autism spectrum disorder (ASD) during early childhood. We investigated sex differences in developmental profiles using the Mullen Scales of Early Learning, autistic symptoms on the ADOS-G, and coexisting behavior problems on the CBCL in 157 boys and 42 girls with ASD aged 1.5-3.9 years. Overall,…
Sex differences in extinction recall in posttraumatic stress disorder: a pilot fMRI study.
Shvil, Erel; Sullivan, Gregory M; Schafer, Scott; Markowitz, John C; Campeas, Miriam; Wager, Tor D; Milad, Mohammed R; Neria, Yuval
2014-09-01
Recent research has found that individuals with posttraumatic stress disorder (PTSD) exhibit an impaired memory of fear extinction compounded by deficient functional activation of key nodes of the fear network including the amygdala, hippocampus, ventromedial prefrontal cortex (vmPFC) and dorsal anterior cingulate cortex (dACC). Research has shown these regions are sexually dimorphic and activate differentially in healthy men and women during fear learning tasks. To explore biological markers of sex differences following exposure to psychological trauma, we used a fear learning and extinction paradigm together with functional magnetic resonance imaging (fMRI) and skin conductance response (SCR) to assess 31 individuals with PTSD (18 women; 13 men) and 25 matched trauma-exposed healthy control subjects (13 women; 12 men). Whereas no sex differences appeared within the trauma-exposed healthy control group, both psychophysiological and neural activation patterns within the PTSD group indicated deficient recall of extinction memory among men and not among women. Men with PTSD exhibited increased activation in the left rostral dACC during extinction recall compared with women with PTSD. These findings highlight the importance of tracking sex differences in fear extinction when characterizing the underlying neurobiological mechanisms of PTSD psychopathology. Copyright © 2014 Elsevier Inc. All rights reserved.
[Changes in structure and function of the family of the adolescent in the last decade (1997-2007)].
Pérez Milena, Alejandro; Martínez Fernández, María Luz; Mesa Gallardo, Inmaculada; Pérez Milena, Rafael; Leal Helmling, Francisco Javier; Jiménez Pulido, Idoia
2009-09-01
To find out the structure and functioning of the family of the adolescent and its changes in the last decade. Cross-sectional descriptive study using questionnaires. Pupils in obligatory secondary education and high-school in one rural (Granada) and one urban (Jaén) area. Self-administered questionnaire (years 1997-2001-2004-2007) in which details of age, sex, family structure and family-Apgar test were recorded. A total of 1356 adolescents participated, 1271 questionnaires valid (259, 386, 246 and 380 respectively per year). Ages 12-18 years, equality of sexes. The nuclear family structure was predominant (78-84%), followed by single parent family in (7-11%), extended (6-7%) and reconstituted (2%). The family function was mainly normal (70-76%), with 30% dysfunction (slight dysfunction 18-21% and severe dysfunction 5-10%). The structure and family function does not vary by sex or the year of study, it is influenced by age: adolescents 16 years with a higher percentage of family dysfunction in 1997/2001 than the rest of ages, declining in the years 2004/2007 (P <0.05 chi(2)), similar to other ages. While the nuclear family in 1997 had a greater number of adolescents with normal family function (P <0.05 chi(2)), in the remaining years there were no significant differences between different family structures. The perception of family function in adolescents has changed and now does not depend on sex, age and structure. Family care during adolescence should focus on promoting positive family dynamics, regardless of family structure.
Li, Ying; Qin, Wen; Jiang, Tianzi; Zhang, Yunting; Yu, Chunshui
2012-01-01
Harm avoidance (HA) is a personality dimension involving the tendency to respond intensely to signals of aversive stimuli. Many previous neuroimaging studies have associated HA scores with the structural and functional organization of the amygdala, but none of these studies have evaluated the correlation between HA score and amygdala resting-state functional connectivity (rsFC). Moreover, the amygdala is not a homogeneous structure, and it has been divided into several structurally and functionally distinct subregions. Investigating the associations between HA score and properties of subregions of the amygdala could greatly improve our understanding of HA. In the present study, using a large sample of 291 healthy young adults, we aimed to uncover correlations between HA scores and the rsFCs of each amygdala subregion and to uncover possible sex-based differences in these correlations. We found that subregions of the amygdala showed different rsFC patterns, which contributed differently to individual HA scores. More specifically, HA scores were correlated with rsFCs between the laterobasal amygdala subregion and temporal and occipital cortices related to emotional information input, between the centromedial subregion and the frontal cortices associated with emotional output control, and between the superficial subregion and the frontal and temporal areas involved in both functions. Moreover, significant gender-based differences were uncovered in these correlations. Our findings provide a more detailed model of association between HA scores and amygdala rsFC, extend our understanding of the connectivity of subregions of the amygdala, and confirm sex-based differences in HA associations.
Romanticism as a function of age, sex, and ethnicity.
Regan, Pamela C; Anguiano, Carlos
2010-12-01
This study examined the association between romanticism (operationalized as mean score on the Romantic Beliefs Scale) and age, sex, and ethnicity in a large community sample (N = 436). Age was negatively correlated with romanticism scores; as age increased, romanticism scores decreased. No sex differences were found; men and women had similar, moderate scores. Although ethnicity largely was unrelated to romanticism, Asian/Pacific Islander participants were significantly more romantic than were African-American participants.
The neuropsychology of sex offenders: a meta-analysis.
Joyal, Christian C; Beaulieu-Plante, Jolyane; de Chantérac, Antoine
2014-04-01
Typically, neuropsychological studies of sex offenders have grouped together different types of individuals and different types of measures. This is why results have tended to be nonspecific and divergent across studies. Against this background, the authors undertook a review of the literature regarding the neuropsychology of sex offenders, taking into account subgroups based on criminological theories. They also conducted a meta-analysis of the data to demonstrate the cognitive heterogeneity of sex offenders statistically. Their main objective was to test the hypothesis to the effect that the neuropsychological deficits of sex offenders are not broad and generalized compared with specific subgroups of participants based on specific measures. In all, 23 neuropsychological studies reporting data on 1,756 participants were taken into consideration. As expected, a highly significant, broad, and heterogeneous overall effect size was found. Taking subgroups of participants and specific cognitive measures into account significantly improved homogeneity. Sex offenders against children tended to obtain lower scores than did sex offenders against adults on higher order executive functions, whereas sex offenders against adults tended to obtain results similar to those of non-sex offenders, with lower scores in verbal fluency and inhibition. However, it is concluded that neuropsychological data on sex offenders are still too scarce to confirm these trends or to test more precise hypotheses. For greater clinical relevance, future neuropsychological studies should consider specific subgroups of participants and measures to verify the presence of different cognitive profiles.
Females have greater left ventricular twist mechanics than males during acute reductions to preload.
Williams, Alexandra M; Shave, Rob E; Stembridge, Mike; Eves, Neil D
2016-07-01
Compared to males, females have smaller left ventricular (LV) dimensions and volumes, higher ejection fractions (EF), and higher LV longitudinal and circumferential strain. LV twist mechanics determine ventricular function and are preload-dependent. Therefore, the sex differences in LV structure and myocardial function may result in different mechanics when preload is altered. This study investigated sex differences in LV mechanics during acute challenges to preload. With the use of conventional and speckle-tracking echocardiography, LV structure and function were assessed in 20 males (24 ± 6.2 yr) and 20 females (23 ± 3.1 yr) at baseline and during progressive levels of lower body negative pressure (LBNP). Fourteen participants (8 males, 6 females) were also assessed following a rapid infusion of saline. LV end-diastolic volume, end-systolic volume, stroke volume (SV), and EF were reduced in both groups during LBNP (P < 0.001). While males had greater absolute volumes (P < 0.001), there were no sex differences in allometrically scaled volumes at any stage. Sex differences were not detected at baseline in basal rotation, apical rotation, or twist. Apical rotation and twist increased in both groups (P < 0.001) with LBNP. At -60 mmHg, females had greater apical rotation (P = 0.009), twist (P = 0.008), and torsion (P = 0.002) and faster untwisting velocity (P = 0.02) than males. There were no differences in mechanics following saline infusion. Females have larger LV twist and a faster untwisting velocity than males during large reductions to preload, supporting that females have a greater reliance on LV twist mechanics to maintain SV during severe reductions to preload. Copyright © 2016 the American Physiological Society.
Chao, Thomas; Radoncic, Vanya; Hien, Denise; Bedi, Gillinder; Haney, Margaret
2018-04-01
Stress responding is linked to drug use, but little is known about stress responses in cannabis smokers. We investigated acute stress responding in cannabis smokers as a function of trauma exposure and sex, and relationships between stress responses and cannabis relapse. 125 healthy, non-treatment-seeking daily cannabis smokers (23F, 102 M) completed the Trier Social Stress Task (TSST), a standardized laboratory stressor; subsets also completed a trauma questionnaire (n = 106) and a laboratory cannabis relapse measure (n = 54). Stress responding was assessed with heart rate (HR), salivary cortisol (CORT), and self-rated mood. Cannabis smokers reporting at least one trauma exposure had higher CORT and anxiety overall compared to those reporting no trauma. Stress responding did not differ as a function of binary trauma exposure, although total number of exposures correlated positively with CORT and anxiety during stress. Females reported increased nervousness after stress relative to males matched to the females for cannabis and cigarette use. An interactive effect of sex and trauma on HR suggested that females with trauma exposure have increased cardiovascular stress responding relative to those without such exposure, with no differential effect in males. Stress responding did not predict laboratory cannabis relapse. We report differences in acute stress responding as a function of trauma, sex, and their interaction in a large sample of relatively homogenous cannabis smokers. Further investigation of how trauma impacts stress responding in male and female cannabis smokers, and how this relates to different aspects of cannabis use, is warranted. Copyright © 2018 Elsevier B.V. All rights reserved.
Mboya, M M
1998-08-01
This study examined (a) sex and age variations for scores on Self-concept of Academic Ability and academic achievement among 244 African adolescents attending a coeducational high school and (b) correlations between scores on Self-concept of Academic Ability and academic achievement by sex and age. No significant sex differences were found, but there were significant age differences on the Self-concept scores and measures of English, science, and history but not in mathematics. A significant positive correlation was found between Self-concept scores and academic achievement for boys and girls and in all age groups, but the magnitude of the correlations with achievement in mathematics was stronger among boys than among girls.
Self-reported sex differences in high-functioning adults with autism: a meta-analysis.
Moseley, R L; Hitchiner, R; Kirkby, J A
2018-01-01
Sex differences in autistic symptomatology are believed to contribute to the mis- and missed diagnosis of many girls and women with an autism spectrum condition (ASC). Whilst recent years have seen the emergence of clinical and empirical reports delineating the profile of young autistic girls, recognition of sex differences in symptomatology in adulthood is far more limited. We chose here to focus on symptomatology as reported using a screening instrument, the Ritvo Autism Asperger Diagnostic Scale-Revised (RAADS-R). In a meta-analysis, we pooled and analysed RAADS-R data from a number of experimental groups. Analysis of variance (ANOVA) searched for the presence of main effects of Sex and Diagnosis and for interactions between these factors in our sample of autistic and non-autistic adults. In social relatedness and circumscribed interests, main effects of Diagnosis revealed that as expected, autistic adults reported significantly greater lifetime prevalence of symptoms in these domains; an effect of Sex, in circumscribed interests, also suggested that males generally reported more prevalent symptoms than females. An interaction of Sex and Diagnosis in language symptomatology revealed that a normative sex difference in language difficulties was attenuated in autism. An interaction of Sex and Diagnosis in the sensorimotor domain revealed the opposite picture: a lack of sex differences between typically developing men and women and a greater prevalence of sensorimotor symptoms in autistic women than autistic men. We discuss the literature on childhood sex differences in relation to those which emerged in our adult sample. Where childhood sex differences fail to persist in adulthood, several interpretations exist, and we discuss, for example, an inherent sampling bias that may mean that only autistic women most similar to the male presentation are diagnosed. The finding that sensorimotor symptomatology is more highly reported by autistic women is a finding requiring objective confirmation, given its potential importance in diagnosis.
Gauthier, Christophe T; Duyme, Michel; Zanca, Michel; Capron, Christiane
2009-02-01
Neuroimaging studies investigating the neural correlates of verbal fluency (VF) focused on sex differences without taking into account behavioural variation. Nevertheless, group differences in this verbal ability might account for neurocognitive differences elicited between men and women. The aim of this study was to test sex and performance level effects and the combination of these on cerebral activation. Four samples of 11 healthy students (N=44) selected on the basis of sex and contrasted VF scores, high fluency (HF) versus low fluency (LF), performed a covert phonological VF task during scans. Within- and between-group analyses were conducted. Consistent with previous studies, for each sample, the whole-group analysis reported activation in the inferior frontal gyrus (IFG), insula, anterior cingulate cortex (ACC), medial frontal gyrus (mFG), superior (SPL) and inferior parietal lobules (IPL), inferior visual areas, cerebellum, thalamus and basal ganglia. Between-group analyses showed an interaction between sexes and performances in the right precuneus, left ACC, right IFG and left dorsolateral prefrontal cortex (dlPFC). HF men showed more activation than LF ones in the right precuneus and left dlPFC. LF men showed more activation in the right IFG than HF ones and LF women elicited more activation in the left ACC than HF ones. A sex main effect was found regardless of performance in the left inferior temporal gyrus (ITG), cerebellum, anterior and posterior cingulate cortexes and in the right superior frontal gyrus (SFG) and dlPFC, lingual gyrus and ACC, with men eliciting significantly greater activations than women. A performance main effect was found for the left ACC and the left cerebellum regardless of sex. LF subjects had stronger activations than HF ones in the ACC whereas HF subjects showed stronger activations in the cerebellum. Activity in three discrete subregions of the ACC is related to sex, performance and their interaction, respectively. Our findings emphasize the need to consider sex and performance level in functional imaging studies of VF.
Memisevic, H; Sinanovic, O
2014-09-01
Executive function is very important in the children's overall development. The goal of this study was to assess the executive function in children with intellectual disability (ID) through the use of the Behavior Rating Inventory of Executive Function (BRIEF) teacher version. An additional goal was to examine the differences in executive function in relation to child's sex, level and aetiology of ID. The sample consisted of 90 children with ID attending two special education schools in Sarajevo, Bosnia and Herzegovina. There were 42 children with mild ID and 48 children with moderate ID. Of those, 54 were boys and 36 were girls. Children were classified into three etiological categories: 30 children with Down syndrome, 30 children with other genetic cause or organic brain injury and 30 children with unknown aetiology of ID. Special education teachers, who knew the children for at least 6 months filled the BRIEF. Children with ID had a significant deficit in executive function as measured by the BRIEF. There were no statistically significant differences in executive function in relation to the child's sex. Level of ID had a significant effect on executive function. In relation to the aetiology of ID, the only significant difference was on the Shift scale of the BRIEF. Knowing what executive function is most impaired in children with ID will help professionals design better intervention strategies. More attention needs to be given to the assessment of executive function and its subsequent intervention in the school settings. © 2013 MENCAP and International Association of the Scientific Study of Intellectual and Developmental Disabilities and John Wiley & Sons Ltd.
Baron-Cohen, Simon; Richler, Jennifer; Bisarya, Dheraj; Gurunathan, Nhishanth; Wheelwright, Sally
2003-01-01
Systemizing is the drive to analyse systems or construct systems. A recent model of psychological sex differences suggests that this is a major dimension in which the sexes differ, with males being more drawn to systemize than females. Currently, there are no self-report measures to assess this important dimension. A second major dimension of sex differences is empathizing (the drive to identify mental states and respond to these with an appropriate emotion). Previous studies find females score higher on empathy measures. We report a new self-report questionnaire, the Systemizing Quotient (SQ), for use with adults of normal intelligence. It contains 40 systemizing items and 20 control items. On each systemizing item, a person can score 2, 1 or 0, so the SQ has a maximum score of 80 and a minimum of zero. In Study 1, we measured the SQ of n = 278 adults (114 males, 164 females) from a general population, to test for predicted sex differences (male superiority) in systemizing. All subjects were also given the Empathy Quotient (EQ) to test if previous reports of female superiority would be replicated. In Study 2 we employed the SQ and the EQ with n = 47 adults (33 males, 14 females) with Asperger syndrome (AS) or high-functioning autism (HFA), who are predicted to be either normal or superior at systemizing, but impaired at empathizing. Their scores were compared with n = 47 matched adults from the general population in Study 1. In Study 1, as predicted, normal adult males scored significantly higher than females on the SQ and significantly lower on the EQ. In Study 2, again as predicted, adults with AS/HFA scored significantly higher on the SQ than matched controls, and significantly lower on the EQ than matched controls. The SQ reveals both a sex difference in systemizing in the general population and an unusually strong drive to systemize in AS/HFA. These results are discussed in relation to two linked theories: the 'empathizing-systemizing' (E-S) theory of sex differences and the extreme male brain (EMB) theory of autism. PMID:12639333
Rigon, Arianna; Turkstra, Lyn; Mutlu, Bilge; Duff, Melissa
2016-10-01
Although moderate to severe traumatic brain injury (TBI) leads to facial affect recognition impairments in up to 39% of individuals, protective and risk factors for these deficits are unknown. The aim of the current study was to examine the effect of sex on emotion recognition abilities following TBI. We administered two separate emotion recognition tests (one static and one dynamic) to 53 individuals with moderate to severe TBI (females = 28) and 49 demographically matched comparisons (females = 22). We then investigated the presence of a sex-by-group interaction in emotion recognition accuracy. In the comparison group, there were no sex differences. In the TBI group, however, females significantly outperformed males in the dynamic (but not the static) task. Moreover, males (but not females) with TBI performed significantly worse than comparison participants in the dynamic task. Further analysis revealed that sex differences in emotion recognition abilities within the TBI group could not be explained by lesion location, TBI severity, or other neuropsychological variables. These findings suggest that sex may serve as a protective factor for social impairment following TBI and inform clinicians working with TBI as well as research on the neurophysiological correlates of sex differences in social functioning.
Taziaux, Melanie; Staphorsius, Annemieke S; Ghatei, Mohammad A; Bloom, Stephen R; Swaab, Dick F; Bakker, Julie
2016-06-01
Since the discovery of its central role in reproduction, our functional neuroanatomical knowledge of the hypothalamic kisspeptin system is predominantly based on animal studies. Although sex differences in kisspeptin expression have been shown in humans in adulthood, the developmental origin of this sex difference is unknown. Our objectives were to determine the following: 1) when during development the sex difference in kisspeptin expression in the infundibular nucleus would emerge and 2) whether this sex difference is related to sexual orientation or transsexuality. Postmortem hypothalamic tissues were collected by The Netherlands Brain Bank, and sections were stained for kisspeptin by immunohistochemistry. Hypothalami of 43 control subjects were categorized into three periods: infant/prepubertal (six girls, seven boys), adult (11 women, seven men), and elderly (six aged women, six aged men). Eight male-to-female (MTF) transsexuals, three HIV(+) heterosexual men, and five HIV(+) homosexual men were also analyzed. We estimated the total number of kisspeptin-immunoreactive neurons within the infundibular nucleus. Quantitative analysis confirmed that the human infundibular kisspeptin system exhibits a female-dominant sex difference. The number of kisspeptin neurons is significantly greater in the infant/prepubertal and elderly periods compared with the adult period. Finally, in MTF transsexuals, but not homosexual men, a female-typical kisspeptin expression was observed. These findings suggest that infundibular kisspeptin neurons are sensitive to circulating sex steroid hormones throughout life and that the sex reversal observed in MTF transsexuals might reflect, at least partially, an atypical brain sexual differentiation.
Variation in orbitofrontal cortex volume: relation to sex, emotion regulation and affect.
Welborn, B Locke; Papademetris, Xenophon; Reis, Deidre L; Rajeevan, Nallakkandi; Bloise, Suzanne M; Gray, Jeremy R
2009-12-01
Sex differences in brain structure have been examined extensively but are not completely understood, especially in relation to possible functional correlates. Our two aims in this study were to investigate sex differences in brain structure, and to investigate a possible relation between orbitofrontal cortex subregions and affective individual differences. We used tensor-based morphometry to estimate local brain volume from MPRAGE images in 117 healthy right-handed adults (58 female), age 18-40 years. We entered estimates of local brain volume as the dependent variable in a GLM, controlling for age, intelligence and whole-brain volume. Men had larger left planum temporale. Women had larger ventromedial prefrontal cortex (vmPFC), right lateral orbitofrontal (rlOFC), cerebellum, and bilateral basal ganglia and nearby white matter. vmPFC but not rlOFC volume covaried with self-reported emotion regulation strategies (reappraisal, suppression), expressivity of positive emotions (but not of negative), strength of emotional impulses, and cognitive but not somatic anxiety. vmPFC volume statistically mediated sex differences in emotion suppression. The results confirm prior reports of sex differences in orbitofrontal cortex structure, and are the first to show that normal variation in vmPFC volume is systematically related to emotion regulation and affective individual differences.
Pattanayak, Rojalin; Mishra, Geetanjali; Omkar; Chanotiya, Chandan Singh; Rout, Prasant Kumar; Mohanty, Chandra Sekhar
2014-11-01
Insect hydrocarbons (HCs) primarily serve as a waterproofing cuticular layer and function extensively in chemical communication by facilitating species, sex, and colony recognition. In this study, headspace solid-phase microextraction is employed for investigating the sex-specific volatile HC profile of five ladybirds collected from Lucknow, India namely, Coccinella septempunctata (L.), Coccinella transversalis (Fabr.), Menochilus sexmaculatus (Fabr.), Propylea dissecta (Mulsant), and Anegleis cardoni (Weise) for the first time. Major compounds reported in C. septempunctata, C. transversalis, and A. cardoni are methyl-branched saturated HCs, whereas in M. sexmaculatus, and P. dissecta, they are unsaturated HCs. Other than A. cardoni, both the sexes of the other four ladybirds had similar compounds at highest peak but with statistically significant differences. However, in A. cardoni, which is a beetle with a narrow niche, the major compound in both male and female was different. The difference in volatile HC profile of the sexes of the five ladybirds indicates that gender-specific differences primarily exist due to quantitative differences in chemicals with only very few chemicals being unique to a gender. This variation in semiochemicals might have a role in behavioral or ecological aspects of the studied ladybirds. © 2014 Wiley Periodicals, Inc.
Kynyk, Jessica A; Mastronarde, John G; McCallister, Jennifer W
2011-01-01
asthma is a common chronic disease with significant clinical impact worldwide. Sex-related disparities in asthma epidemiology and morbidity exist but debate continues regarding the mechanisms for these differences. There is a need to review the recent findings for asthma care providers and to highlight areas in need of additional research. recent data illustrate striking sex-related differences in asthma epidemiology and disease expression. Studies show an increased incidence of asthma in women. Data demonstrate that asthmatic women have a poorer quality of life and increased utilization of healthcare compared to their male counterparts despite similar medical treatment and baseline pulmonary function. Research continues to explore hypotheses for these differences including the potential influences of the female sex hormones, altered perception of airflow obstruction, increased bronchial hyper-responsiveness, and medication compliance and technique. However, no single explanation has been able to fully explain the disparities. women are more likely to be diagnosed with asthma and suffer greater morbidity than men. The physiologic mechanisms for these differences are not well understood. Understanding sex-related differences in asthma and providing patients with education geared toward these disparities are important in establishing effective, individualized asthma management strategies for all patients.
Different Context but Similar Cognitive Structures: Older Adults in Rural Bangladesh.
Sternäng, Ola; Lövdén, Martin; Kabir, Zarina N; Hamadani, Jena D; Wahlin, Åke
2016-06-01
Most research in cognitive aging is based on literate participants from high-income and Western populations. The extent to which findings generalize to low-income and illiterate populations is unknown. The main aim was to examine the structure of between-person differences in cognitive functions among elderly from rural Bangladesh. We used data from the Poverty and Health in Aging (PHA) project in Bangladesh. The participants (n = 452) were in the age range 60-92 years. Structural equation modeling was used to estimate the fit of a five-factor model (episodic recall, episodic recognition, verbal fluency, semantic knowledge, processing speed) and to examine whether the model generalized across age, sex, and literacy. This study demonstrates that an established model of cognition is valid also among older persons from rural Bangladesh. The model demonstrated strong (or scalar) invariance for age, and partial strong invariance for sex and literacy. Semantic knowledge and processing speed showed weak (or metric) sex invariance, and semantic knowledge demonstrated also sensitivity to illiteracy. In general, women performed poorer on all abilities. The structure of individual cognitive differences established in Western populations also fits a population in rural Bangladesh well. This is an important prerequisite for comparisons of cognitive functioning (e.g., declarative memory) across cultures. It is also worth noting that absolute sex differences in cognitive performance among rural elderly in Bangladesh differ from those usually found in Western samples.
Lee, S W; Jeong, B S; Choi, J; Kim, J-W
2015-01-01
Men tend to have greater positive responses than women to explicit visual erotic stimuli (EVES). However, it remains unclear, which brain network makes men more sensitive to EVES and which factors contribute to the brain network activity. In this study, we aimed to assess the effect of sex difference on brain connectivity patterns by EVES. We also investigated the association of testosterone with brain connection that showed the effects of sex difference. During functional magnetic resonance imaging scans, 14 males and 14 females were asked to see alternating blocks of pictures that were either erotic or non-erotic. Psychophysiological interaction analysis was performed to investigate the functional connectivity of the nucleus accumbens (NA) as it related to EVES. Men showed significantly greater EVES-specific functional connection between the right NA and the right lateral occipital cortex (LOC). In addition, the right NA and the right LOC network activity was positively correlated with the plasma testosterone level in men. Our results suggest that the reason men are sensitive to EVES is the increased interaction in the visual reward networks, which is modulated by their plasma testosterone level.
Sex differences in effective fronto-limbic connectivity during negative emotion processing.
Lungu, Ovidiu; Potvin, Stéphane; Tikàsz, Andràs; Mendrek, Adrianna
2015-12-01
In view of the greater prevalence of depression and anxiety disorders in women than in men, functional magnetic resonance imaging (fMRI) studies have examined sex-differences in brain activations during emotion processing. Comparatively, sex-differences in brain connectivity received little attention, despite evidence for important fronto-limbic connections during emotion processing across sexes. Here, we investigated sex-differences in fronto-limbic connectivity during negative emotion processing. Forty-six healthy individuals (25 women, 21 men) viewed negative, positive and neutral images during an fMRI session. Effective connectivity between significantly activated regions was examined using Granger causality and psychophysical interaction analyses. Sex steroid hormones and feminine-masculine traits were also measured. Subjective ratings of negative emotional images were higher in women than in men. Across sexes, significant activations were observed in the dorso-medial prefrontal cortex (dmPFC) and the right amygdala. Granger connectivity from right amygdala was significantly greater than that from dmPFC during the 'high negative' condition, an effect driven by men. Magnitude of this effect correlated negatively with highly negative image ratings and feminine traits and positively with testosterone levels. These results highlight critical sex differences in brain connectivity during negative emotion processing and point to the fact that both biological (sex steroid hormones) and psychosocial (gender role and identity) variables contribute to them. As the dmPFC is involved in social cognition and action planning, and the amygdala-in threat detection, the connectivity results suggest that compared to women, men have a more evaluative, rather than purely affective, brain response during negative emotion processing. Copyright © 2015 Elsevier Ltd. All rights reserved.
Molecular evidence for gender differences in the migratory behaviour of a small seabird.
Medeiros, Renata J; King, R Andrew; Symondson, William O C; Cadiou, Bernard; Zonfrillo, Bernard; Bolton, Mark; Morton, Rab; Howell, Stephen; Clinton, Anthony; Felgueiras, Marcial; Thomas, Robert J
2012-01-01
Molecular sexing revealed an unexpectedly strong female bias in the sex ratio of pre-breeding European Storm Petrels (Hydrobates pelagicus), attracted to playback of conspecific calls during their northwards migration past SW Europe. This bias was consistent across seven years, ranging from 80.8% to 89.7% female (mean annual sex ratio ± SD = 85.5% female ±4.1%). The sex ratio did not differ significantly from unity (i.e., 50% female) among (i) Storm Petrel chicks at a breeding colony in NW France, (ii) adults found dead on beaches in Southern Portugal, (iii) breeding birds attending nest burrows in the UK, captured by hand, and (iv) adults captured near a breeding colony in the UK using copies of the same sound recordings as used in Southern Europe, indicating that females are not inherently more strongly attracted to playback calls than males. A morphological discriminant function analysis failed to provide a good separation of the sexes, showing the importance of molecular sexing for this species. We found no sex difference in the seasonal or nocturnal timing of migration past Southern Europe, but there was a significant tendency for birds to be caught in sex-specific aggregations. The preponderance of females captured in Southern Europe suggests that the sexes may differ in migration route or in their colony-prospecting behaviour during migration, at sites far away from their natal colonies. Such differences in migration behaviour between males and females are poorly understood but have implications for the vulnerability of seabirds to pollution and environmental change at sea during the non-breeding season.
Sex Differences in the Perceived Importance of Mentoring Functions
ERIC Educational Resources Information Center
Levesque, Laurie L.; O'Neill, Regina M.; Nelson, Teresa; Dumas, Colette
2005-01-01
Purpose: To be the first study to consider the difference between men's and women's perceptions of most important mentoring functions. Design/methodology/approach: Survey recipients identified the three most important things that mentors can do for their proteges. Two independent coders categorized the behaviors listed by the 637 respondents.…
Nazarpour, Soheila; Simbar, Masoumeh; Ramezani Tehrani, Fahimeh; Alavi Majd, Hamid
2017-07-01
The sex lives of women are strongly affected by menopause. Non-pharmacologic approaches to improving the sexual function of postmenopausal women might prove effective. To compare two methods of intervention (formal sex education and Kegel exercises) with routine postmenopausal care services in a randomized clinical trial. A randomized clinical trial was conducted of 145 postmenopausal women residing in Chalus and Noshahr, Iran. Their sexual function statuses were assessed using the Female Sexual Function Index (FSFI) questionnaire. After obtaining written informed consents, they were randomly assigned to one of three groups: (i) formal sex education, (ii) Kegel exercises, or (iii) routine postmenopausal care. After 12 weeks, all participants completed the FSFI again. Analysis of covariance was used to compare the participants' sexual function before and after the interventions, and multiple linear regression analysis was used to determine the predictive factors for variation in FSFI scores in the postintervention stage. Sexual function was assessed using the FSFI. There were no statistically significant differences in demographic and socioeconomic characteristics and FSFI total scores among the three study groups at the outset of the study. After 12 weeks, the scores of arousal in the formal sex education and Kegel groups were significantly higher compared with the control group (3.38 and 3.15 vs 2.77, respectively). The scores of orgasm and satisfaction in the Kegel group were significantly higher compared with the control group (4.43 and 4.88 vs 3.95 and 4.39, respectively). Formal sex education and Kegel exercises were used as two non-pharmacologic approaches to improve the sexual function of women after menopause. The main strength of this study was its design: a well-organized randomized trial using precise eligibility criteria with a small sample loss. The second strength was the methods of intervention used, namely non-pharmacologic approaches that are simple, easily accessible, and fairly inexpensive. The main limitation of the study was our inability to objectively assess the participants' commitment to exercise and the sexual function of their partners. Sex education programs and Kegel exercises could cause improvements in some domains of sexual function-specifically arousal, orgasm, and satisfaction-in postmenopausal women. Nazarpour S, Simbar M, Tehrani FR, Majd HA. Effects of Sex Education and Kegel Exercises on the Sexual Function of Postmenopausal Women: A Randomized Clinical Trial. J Sex Med 2017;14:959-967. Copyright © 2017 International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.
Male-female differences in Scoliosis Research Society-30 scores in adolescent idiopathic scoliosis.
Roberts, David W; Savage, Jason W; Schwartz, Daniel G; Carreon, Leah Y; Sucato, Daniel J; Sanders, James O; Richards, Benjamin Stephens; Lenke, Lawrence G; Emans, John B; Parent, Stefan; Sarwark, John F
2011-01-01
Longitudinal cohort study. To compare functional outcomes between male and female patients before and after surgery for adolescent idiopathic scoliosis (AIS). There is no clear consensus in the existing literature with respect to sex differences in functional outcomes in the surgical treatment of AIS. A prospective, consecutive, multicenter database of patients who underwent surgical correction for adolescent idiopathic scoliosis was analyzed retrospectively. All patients completed Scoliosis Research Society-30 (SRS-30) questionnaires before and 2 years after surgery. Patients with previous spine surgery were excluded. Data were collected for sex, age, Risser grade, previous bracing history, maximum preoperative Cobb angle, curve correction at 2 years, and SRS-30 domain scores. Paired sample t tests were used to compare preoperative and postoperative scores within each sex. Independent sample t tests were used to compare scores between sexes. A P value of <0.05 was considered statistically significant. Seven hundred forty-four patients (621 females and 123 males) were included. On average, males were 1 year older than females. There were no differences between sexes in Risser grade, bracing history, maximum curve magnitude, or correction after surgery. Both males and females had similar improvement in all SRS-30 domains after surgery. Self-image/appearance had the greatest relative improvement. Males had better self-image/appearance scores preoperatively, better pain scores at 2 years, and better mental health and total scores both preoperatively and at 2 years. Both males and females were similarly satisfied with surgery. Males treated with surgery for AIS report better preoperative self-image, less postoperative pain, and better mental health than females. These differences may be clinically significant. For both males and females, the most beneficial effect of surgery is improved self-image/appearance. Overall, the benefits of surgery for AIS are similar for both sexes.
The Evolution of Sex Chromosomes and Dosage Compensation in Plants
Shearn, Rylan; Marais, Gabriel AB
2017-01-01
Plant sex chromosomes can be vastly different from those of the few historical animal model organisms from which most of our understanding of sex chromosome evolution is derived. Recently, we have seen several advancements from studies on green algae, brown algae, and land plants that are providing a broader understanding of the variable ways in which sex chromosomes can evolve in distant eukaryotic groups. Plant sex-determining genes are being identified and, as expected, are completely different from those in animals. Species with varying levels of differentiation between the X and Y have been found in plants, and these are hypothesized to be representing different stages of sex chromosome evolution. However, we are also finding that sex chromosomes can remain morphologically unchanged over extended periods of time. Where degeneration of the Y occurs, it appears to proceed similarly in plants and animals. Dosage compensation (a phenomenon that compensates for the consequent loss of expression from the Y) has now been documented in a plant system, its mechanism, however, remains unknown. Research has also begun on the role of sex chromosomes in sexual conflict resolution, and it appears that sex-biased genes evolve similarly in plants and animals, although the functions of these genes remain poorly studied. Because the difficulty in obtaining sex chromosome sequences is increasingly being overcome by methodological developments, there is great potential for further discovery within the field of plant sex chromosome evolution. PMID:28391324
Solianik, Rima; Skurvydas, Albertas; Mickevičienė, Dalia; Brazaitis, Marius
2014-10-01
The main aim of this study was to compare the thermal responses and the responses of cognitive and motor functions to intermittent cold stress between males and females. The intermittent cold stress continued until rectal temperature (TRE) reached 35.5°C or for a maximum of 170 min. Thermal response and motor and cognitive performance were monitored. During intermittent cold stress, body temperature variables decreased in all subjects (P < 0.001) and did not differ between sexes. The presence of fast and slow cooling types for participants with similar effect on physiological variables were observed; thus the different rate coolers were grouped together and were attributed only sex specific responses. Overall, TRE cooling rate and cold strain index did not differ between sexes. Maximal voluntary contraction (MVC) decreased after intermittent cold exposure only in males (P < 0.001), whereas changes in muscle electromyography (EMG) activity did not differ between sexes. The effects of intermittent cold stress on electrically evoked muscle properties, spinal (H-reflex), and supraspinal (V-waves) reflexes did not differ between sexes. Intermittent cold-induced cognitive perturbation of attention and memory task performance was greater in males (P < 0.05). Contrary to our expectations, the results of the present study indicated that males and females experience similar thermal stress induced by intermittent whole-body cold immersion. Although no sex-specific differences were observed in muscle EMG activity, involuntary muscle properties, spinal and supraspinal reflexes, some of the sex differences observed (e.g., lower isometric MVC and greater cognitive perturbation in males) support the view of sex-specific physiological responses to core temperature decrease. Copyright © 2014 Elsevier Inc. All rights reserved.
Li, Chiang-Shan Ray; Kosten, Thomas R; Sinha, Rajita
2005-03-01
Because stress mediates drug seeking and relapse, and sex differences have been observed in stress and in the development of cocaine addiction, in this study we used functional neuroimaging to examine the effect of sex on stress responses in abstinent cocaine users. In a functional magnetic resonance imaging session, 17 male and 10 female cocaine-dependent subjects participated in script-guided imagery of neutral or stress situations. Subjects rated imagery vividness, anxiety, and cocaine craving for each trial. Brain activation during the stress and neutral imagery periods relative to their own baseline was examined in individual subjects. Sex contrast was obtained in second-level group analysis. Female subjects demonstrated more activation, compared with male subjects, in left middle frontal, anterior cingulate, and inferior frontal cortices and insula, and right cingulate cortex during stress imagery. Region of interest analysis showed that the change of activity in left anterior cingulate and right posterior cingulate cortices both correlated inversely with the change of craving rating during stress imagery. The greater left frontolimbic activity in women suggests that women might use more verbal coping strategies than do men while experiencing stress. The results also suggest a distinct role of the cingulate cortices in modulating stress-induced cocaine craving.
Sex differences in sensorimotor mu rhythms during selective attentional processing.
Popovich, C; Dockstader, C; Cheyne, D; Tannock, R
2010-12-01
We used magnetoencephalography to investigate the effect of directed attention on sensorimotor mu (8-12 Hz) response (mu reactivity) to non-painful electrical stimulation of the median nerve in healthy adults. Mu desynchronization in the 10-12 Hz bandwidth is typically observed during higher-order cognitive functions including selective attentional processing of sensorimotor information (Pfurtscheller, Neuper, & Krauz, 2000). We found attention-related sex differences in mu reactivity, with females showing (i) prolonged mu desynchrony when attending to somatosensory stimuli, (ii) attentional modulation of the mu response based on whether attention was directed towards or away from somatosensory stimuli, which was absent in males, and (iii) a trend for greater neuronal excitability of the primary somatosensory region suggesting greater physiological responsiveness to sensory stimulation overall. Our findings suggest sex differences in attentional control strategies when processing somatosensory stimuli, whose salience may be greater for females. These sex differences in attention to somatosensory stimuli may help elucidate the well-documented sex biases in pain processing wherein females typically report greater sensitivity to experimental and clinical pain. Copyright © 2010 Elsevier Ltd. All rights reserved.
Gaznick, Natassia; Bechara, Antoine; Tranel, Daniel
2014-01-01
Patterns of smoking behavior vary between the sexes. There is evidence that decision making, which is one of the key "executive functions" necessary for making life-style modifications such as smoking cessation, is relatively lateralized to the right hemisphere in males and left hemisphere in females. In the current study, we examined whether the side of brain lesion has a differential effect on smoking behavior between the sexes. We hypothesized sex differences in smoking cessation based on lesion side. Participants were 49 males and 50 females who were smoking at the time of lesion onset. The outcome variable was abstinence from smoking (quit rate) at least one year post lesion. We found that in patients with left-hemisphere damage, quit rates were significantly higher in males than in females; however, in patients with right-hemisphere damage, quit rates were not statistically different. The findings support previous cognitive neuroscience literature showing that components of behavior responsible for maintaining addiction tend to be more strongly lateralized in males, whereas in females there is a more bilateral distribution. Our study provides further evidence for differences in lateralization of complex behavior between the sexes, which has significant implications for differences in treatment strategies between the sexes.
Assessment of craniometric traits in South Indian dry skulls for sex determination.
Ramamoorthy, Balakrishnan; Pai, Mangala M; Prabhu, Latha V; Muralimanju, B V; Rai, Rajalakshmi
2016-01-01
The skeleton plays an important role in sex determination in forensic anthropology. The skull bone is considered as the second best after the pelvic bone in sex determination due to its better retention of morphological features. Different populations have varying skeletal characteristics, making population specific analysis for sex determination essential. Hence the objective of this investigation is to obtain the accuracy of sex determination using cranial parameters of adult skulls to the highest percentage in South Indian population and to provide a baseline data for sex determination in South India. Seventy adult preserved human skulls were taken and based on the morphological traits were classified into 43 male skulls and 27 female skulls. A total of 26 craniometric parameters were studied. The data were analyzed by using the SPSS discriminant function. The analysis of stepwise, multivariate, and univariate discriminant function gave an accuracy of 77.1%, 85.7%, and 72.9% respectively. Multivariate direct discriminant function analysis classified skull bones into male and female with highest levels of accuracy. Using stepwise discriminant function analysis, the most dimorphic variable to determine sex of the skull, was biauricular breadth followed by weight. Subjecting the best dimorphic variables to univariate discriminant analysis, high levels of accuracy of sexual dimorphism was obtained. Percentage classification of high accuracies were obtained in this study indicating high level of sexual dimorphism in the crania, setting specific discriminant equations for the gender determination in South Indian people. Copyright © 2015 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.
Sex Specific Effect of Prenatal Testosterone on Language Lateralization in Children
ERIC Educational Resources Information Center
Lust, J. M.; Geuze, R. H.; Van de Beek, C.; Cohen-Kettenis, P. T.; Groothuis, A. G. G.; Bouma, A.
2010-01-01
Brain lateralization refers to the division of labour between the two hemispheres in controlling a wide array of functions and is remarkably well developed in humans. Based on sex differences in lateralization of handedness and language, several hypotheses have postulated an effect of prenatal exposure to testosterone on human lateralization…
Preschoolers' Beliefs about Sex and Age Differences in Emotionality.
ERIC Educational Resources Information Center
Karbon, Mariss; And Others
1992-01-01
Assesses beliefs of 32 male and 35 female middle-class preschool children about the frequency and intensity with which girls, boys, women, and men experience anger, sadness, and happiness. Children's beliefs are complex; they vary as a function of the target person's age and sex and of the specific emotion. (SLD)
Endocrinology of Species Differences in Sexually Dichromatic Signals
Diana K. Hews; Vanessa S. Quinn
2003-01-01
Many animals have conspicuous social signals. Often these signals are expressed in one sex and function in the context of mate choice, intrasexual competition, or both (Andersson 1994; Bradbury and Vehrencamp 1998). A more complete understanding of sex-specific signals will come from integrative studies within a phylogenetic context (Ryan, Autumn, and Wake 1998)....
Assessment of Spirituality as a Function of Quality of Life In Prostate Cancer Patients
1999-10-01
Viral infection or bacteria Genetics Worrying or stress Having sex with different partners Having sex without wearing a condom Masturbating God teaching...since diagnosis, the majority noted that their religious belief and/or practices had increased. About five men in all of the sessions indicated they were
Sex Differential Item Functioning in the Inventory of Early Development III Social-Emotional Skills
ERIC Educational Resources Information Center
Beaver, Jessica L.; French, Brian F.; Finch, W. Holmes; Ullrich-French, Sarah C.
2014-01-01
Social-emotional (SE) skills in the early developmental years of children influence outcomes in psychological, behavioral, and learning domains. The adult ratings of a child's SE skills can be influenced by sex stereotypes. These rating differences could lead to differential conclusions about developmental progress or risk. To ensure that…
Sex and Gender Differences in Risk, Pathophysiology and Complications of Type 2 Diabetes Mellitus.
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.
Neuroanatomical and Symptomatic Sex Differences in Individuals at Clinical High Risk for Psychosis.
Guma, Elisa; Devenyi, Gabriel A; Malla, Ashok; Shah, Jai; Chakravarty, M Mallar; Pruessner, Marita
2017-01-01
Sex differences have been widely observed in clinical presentation, functional outcome and neuroanatomy in individuals with a first-episode of psychosis, and chronic patients suffering from schizophrenia. However, little is known about sex differences in the high-risk stages for psychosis. The present study investigated sex differences in cortical and subcortical neuroanatomy in individuals at clinical high risk (CHR) for psychosis and healthy controls (CTL), and the relationship between anatomy and clinical symptoms in males at CHR. Magnetic resonance images were collected in 26 individuals at CHR (13 men) and 29 CTLs (15 men) to determine total and regional brain volumes and morphology, cortical thickness, and surface area (SA). Clinical symptoms were assessed with the brief psychiatric rating scale. Significant sex-by-diagnosis interactions were observed with opposite directions of effect in male and female CHR subjects relative to their same-sex controls in multiple cortical and subcortical areas. The right postcentral, left superior parietal, inferior parietal supramarginal, and angular gyri [<5% false discovery rate (FDR)] were thicker in male and thinner in female CHR subjects compared with their same-sex CTLs. The same pattern was observed in the right superior parietal gyrus SA at the regional and vertex level. Using a recently developed surface-based morphology pipeline, we observed sex-specific shape differences in the left hippocampus (<5% FDR) and amygdala (<10% FDR). Negative symptom burden was significantly higher in male compared with female CHR subjects ( p = 0.04) and was positively associated with areal expansion of the left amygdala in males (<5% FDR). Some limitations of the study include the sample size, and data acquisition at 1.5 T. This study demonstrates neuroanatomical sex differences in CHR subjects, which may be associated with variations in symptomatology in men and women with psychotic symptoms.
Sex and Gender Differences in Risk, Pathophysiology and Complications of Type 2 Diabetes Mellitus
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
Kramer, Maxwell; Rao, Prashant; Ercan, Sevinc
2016-01-01
Dosage compensation mechanisms equalize the level of X chromosome expression between sexes. Yet the X chromosome is often enriched for genes exhibiting sex-biased, i.e., imbalanced expression. The relationship between X chromosome dosage compensation and sex-biased gene expression remains largely unexplored. Most studies determine sex-biased gene expression without distinguishing between contributions from X chromosome copy number (dose) and the animal’s sex. Here, we uncoupled X chromosome dose from sex-specific gene regulation in Caenorhabditis elegans to determine the effect of each on X expression. In early embryogenesis, when dosage compensation is not yet fully active, X chromosome dose drives the hermaphrodite-biased expression of many X-linked genes, including several genes that were shown to be responsible for hermaphrodite fate. A similar effect is seen in the C. elegans germline, where X chromosome dose contributes to higher hermaphrodite X expression, suggesting that lack of dosage compensation in the germline may have a role in supporting higher expression of X chromosomal genes with female-biased functions in the gonad. In the soma, dosage compensation effectively balances X expression between the sexes. As a result, somatic sex-biased expression is almost entirely due to sex-specific gene regulation. These results suggest that lack of dosage compensation in different tissues and developmental stages allow X chromosome copy number to contribute to sex-biased gene expression and function. PMID:27356611
Torres-Sánchez, Luisa; López-Carrillo, Lizbeth; Rosado, Jorge L; Rodriguez, Valentina M; Vera-Aguilar, Eunice; Kordas, Katarzyna; García-Vargas, Gonzalo G; Cebrian, Mariano E
2016-11-01
Chronic arsenic (As) exposure decreases adult and children's ability to methylate inorganic As (iAs); however, few studies have examined children's sex differences. We measured urinary concentrations of iAs, monomethylarsonic (MMA), and dimethylarsinic (DMA) acids, and calculated the primary (PMI: MMA/iAs) and secondary (SMI: DMA/MMA) methylation capacity indexes in 591 children 6-8 years in Torreón, Mexico. We determined iAs, MMA, and DMA by hydride generation cryotrapping AAS. Lineal regression models estimated associations between methylation capacity and total As (TAs) or iAs. Interactions with sex were tested at p<0.10. Boys had significantly higher TAs levels, (58.4µg/L) than girls (46.2µg/L). We observed negative associations between TAs and PMI (β=-0.039; p<0.18) and SMI (β=-0.08; p=0.002) with significant sex differences; PMI reduction was significant in boys (β=-0.09; p=0.02) but not in girls (β=0.021; p=0.63), p for interaction=0.06. In contrast, SMI reduction was significantly more pronounced in girls. Furthermore, negative associations PMI (β=-0.19; p<0.001) and SMI (β=-0.35; p<0.001) were a function of urinary iAs levels, independently of TAs; however, the reduction in PMI was more pronounced in boys (β=-0.24; p<0.001; girls β=-0.15; p<0.001), p for interaction=0.04. A significant negative association was observed between SMI and iAs levels without significant sex differences. TAs and iAs associations with metabolite percentages were in good agreement with those observed with methylation indexes. Our results suggest that iAs plays an important role in reducing As methylation ability and that significant sex differences are present in As metabolism. These differences merit further investigation to confirm our findings and their potential implications for arsenic toxicity in children. Copyright © 2016 Elsevier Inc. All rights reserved.
Lenguas, Leticia; Alarcón, José-Antonio; Venancio, Filipa; Kassem, Marta
2012-01-01
Objectives: To examine the activity of jaw muscles at rest and during maximal voluntary clenching (MVC) in children with unilateral posterior crossbite (UPXB) and functional lateral shift in the early mixed dentition and to evaluate sex differences. Material and Methods: The sample included 30 children (15 males, 15 females) aged 6 to 10 years old, with UPXB and functional mandibular lateral shift (≥1.5 mm) in the early mixed dentition. sEMG activity coming from the muscle areas (anterior temporalis [AT], posterior temporalis [PT], masseter [MA] and suprahyoid [SH]) were obtained from both the crossbite (XB) and noncrossbite (NONXB) sides at mandibular rest position. sEMG acti-vity of the bilateral AT and MA muscles sides was obtained during MVC. Asymmetry and activity indexes were calculated for each muscle area at rest and during MVC; the MA/TA ratio during MVC was also determined. Results: At rest, no differences were found between sexes for any muscle areas or asymmetry and activity indexes. No differences were found between XB and NONXB sides. During MVC, however, significant sex differences were found in AT and MA activity, with higher sEMG values in males than in females, on both XB and NONXB sides. Asymmetry indexes, activity indexes and MA/AT ratios did not show significant differences between the sexes. Activity was symmetric both in males and in females. Conclusions: At rest, no sex differences were found, but during MVC males showed higher activity than did females in both XB and NONXB AT and MA muscle areas. Muscular activity was symmetrical at rest and during MVC in both sexes. Sexual dimorphism should be considered in the diagnosis and treatment of UPXB and lateral shift in the early mixed dentition. Key words:Unilateral crossbite, mandibular shift, jaw muscles, sEMG, early mixed dentition. PMID:22926468
Reproduction reduces photosynthetic capacity in females of the subdioecious Honckenya peploides
NASA Astrophysics Data System (ADS)
Sánchez-Vilas, Julia; Retuerto, Rubén
2011-03-01
As a consequence of the different reproductive functions performed by the sexes, sexually dimorphic/polymorphic plants may exhibit gender-related variations in the energy and resources allocated to reproduction, and in the physiological processes that underlie these differences. This study investigated whether the sexes of the subdioecious plant Honckenya peploides differ in ecophysiological traits related to photosynthetic capacity and whether possible differences depend on reproductive status and on the plant's position (edge or centre) in the population. We registered in three sites in NW Spain, the sex and density of shoots of two segregated clumps of plants. These clumps represent an extreme case of sex-ratio variation across space, with separated single-sex clumps of plants. In two of these sites we measured photosynthetic efficiencies, chlorophyll content, and specific leaf areas. In females, reproduction reduced photochemical efficiency, chlorophyll content and increased the specific leaf area, which is a key leaf trait related to photosynthetic capacity. In males, no differences due to reproduction were detected. The position within the clump affected the specific leaf area of the shoots, with shoots growing at the edge having the lowest values, regardless of the sex. Finally, the effects of position in photosynthetic efficiency and chlorophyll content where highly variable among clumps. We conclude that the differential effects of reproduction on sexes may entail different costs that could be crucial in the outcome of interactions between them, contributing to their spatial segregation.
Light availability affects sex lability in a gynodioecious plant.
Varga, Sandra; Kytöviita, Minna-Maarit
2016-11-01
Sex lability (i.e., gender diphasy) in plants is classically linked to the larger resource needs associated with the female sexual function (i.e., seed production) compared to the male function (i.e., pollen production). Sex lability in response to the environment is extensively documented in dioecious species, but has been largely overlooked in gynodioecious plants. Here, we tested whether environmental conditions induce sex lability in the gynodioecious Geranium sylvaticum. We conducted a transplantation experiment in the field where plants with different sex expression were reciprocally transplanted between high light and low light habitats. We measured plants' reproductive output and sex expression over four years. Our results show that sex expression was labile over the study period. The light level at the destination habitat had a significant effect on sexual expression and reproductive output, because plants decreased their reproductive output when transplanted to the low light habitat. Transplantation origin did not affect any parameter measured. This study shows that sex expression in Geranium sylvaticum is labile and related to light availability. Sexually labile plants did not produce more seeds or pollen, and thus, there was no apparent fitness gain in sexually labile individuals. Sex lability in gynodioecious plants may be more common than previously believed because detection of sex lability necessitates data on the same individuals over time, which is rare in sexually dimorphic herbaceous plants. © 2016 Botanical Society of America.
Wisniewski, Amy B; Prendeville, Mary T; Dobs, Adrian S
2005-04-01
This study examined the impact of sex hormones on functional cerebral hemispheric lateralization and cognition in a group of male-to-female transsexuals receiving cross-sex hormone therapy compared to eugonadal men with a male gender identity. Cerebral lateralization was measured with a handedness questionnaire and a visual-split-field paradigm and cognitive tests sensitive to sex hormone exposure (identical pictures, 3-D mental rotation, building memory) were also administered. Endocrine measures on the day of participation for transsexual and control subjects included total testosterone, free testosterone, estradiol, gonadotropins, and sex hormone binding globulin concentrations. Compared to controls, male-to-female transsexuals had elevated estradiol and sex hormone binding globulin concentrations and suppressed testosterone concentrations. Transsexual subjects showed a trend toward less exclusive right-handedness than controls. No group differences were observed on the visual-split-field or cognitive tasks. No direct associations were observed between endocrine measures and the laterality measures and cognitive performance. Previous observations of female-typical patterns in cerebral lateralization and cognitive performance in male-to-female transsexuals were not found in the current study.
Sex-specific inhibition and stimulation of worker-reproductive transition in a termite.
Sun, Qian; Haynes, Kenneth F; Hampton, Jordan D; Zhou, Xuguo
2017-09-06
In social insects, the postembryonic development of individuals exhibits strong phenotypic plasticity in response to the environment, thus generating the caste system. Different from eusocial Hymenoptera, in which queens dominate reproduction and inhibit worker fertility, the primary reproductive caste in termites (kings and queens) can be replaced by neotenic reproductives derived from functionally sterile individuals. Feedback regulation of nestmate differentiation into reproductives has been suggested, but the sex specificity remains inconclusive. In the eastern subterranean termite, Reticulitermes flavipes, we tested the hypothesis that neotenic reproductives regulate worker-reproductive transition in a sex-specific manner. With this R. flavipes system, we demonstrate a sex-specific regulatory mechanism with both inhibitory and stimulatory functions. Neotenics inhibit workers of the same sex from differentiating into additional reproductives but stimulate workers of the opposite sex to undergo this transition. Furthermore, this process is not affected by the presence of soldiers. Our results highlight the reproductive plasticity of termites in response to social cues and provide insights into the regulation of reproductive division of labor in a hemimetabolous social insect.
Sex-specific inhibition and stimulation of worker-reproductive transition in a termite
NASA Astrophysics Data System (ADS)
Sun, Qian; Haynes, Kenneth F.; Hampton, Jordan D.; Zhou, Xuguo
2017-10-01
In social insects, the postembryonic development of individuals exhibits strong phenotypic plasticity in response to the environment, thus generating the caste system. Different from eusocial Hymenoptera, in which queens dominate reproduction and inhibit worker fertility, the primary reproductive caste in termites (kings and queens) can be replaced by neotenic reproductives derived from functionally sterile individuals. Feedback regulation of nestmate differentiation into reproductives has been suggested, but the sex specificity remains inconclusive. In the eastern subterranean termite, Reticulitermes flavipes, we tested the hypothesis that neotenic reproductives regulate worker-reproductive transition in a sex-specific manner. With this R. flavipes system, we demonstrate a sex-specific regulatory mechanism with both inhibitory and stimulatory functions. Neotenics inhibit workers of the same sex from differentiating into additional reproductives but stimulate workers of the opposite sex to undergo this transition. Furthermore, this process is not affected by the presence of soldiers. Our results highlight the reproductive plasticity of termites in response to social cues and provide insights into the regulation of reproductive division of labor in a hemimetabolous social insect.
Sex-specific predictors of inpatient rehabilitation outcomes after traumatic brain injury
Chan, Vincy; Mollayeva, Tatyana; Ottenbacher, Kenneth J.; Colantonio, Angela
2016-01-01
Objective To identify sex-specific predictors of inpatient rehabilitation outcomes among patients with a traumatic brain injury (TBI) from a population based perspective. Design Retrospective cohort study Setting Ontario, Canada Participants Patients in inpatient rehabilitation for a TBI within one year of acute care discharge between 2008/09 and 2011/12 (N=1,730, 70% male, 30% female). Interventions None Main Outcome Measures Inpatient rehabilitation length of stay, total Functional Independence Measure (FIM™) score, and motor and cognitive FIM™ ratings at discharge. Results Sex, as a covariate in multivariable linear regression models, was not a significant predictor of rehabilitation outcomes. While many of the predictors examined were similar across males and females, sex-specific multivariable models identified some predictors of rehabilitation outcome that are specific for males and females; mechanism of injury (p<.0001) was a significant predictor of functional outcome only among females while comorbidities (p<.0001) was a significant predictor for males only. Conclusions Predictors of outcomes after inpatient rehabilitation differed by sex, providing evidence for a sex-specific approach in planning and resource allocation for inpatient rehabilitation services for patients with TBI. PMID:26836952
Considering sex and gender in Alzheimer disease and other dementias.
Podcasy, Jessica L; Epperson, C Neill
2016-12-01
Suffering related to dementia is multifaceted because cognitive and physical functioning slowly deteriorates. Advanced age and sex, two of the most prominent risk factors for dementia, are not modifiable. Lifestyle factors such as smoking, excessive alcohol use, and poor diet modulate susceptibility to dementia in both males and females. The degree to which the resulting health conditions (eg, obesity, type 2 diabetes, and cardiovascular disease) impact dementia risk varies by sex. Depending on the subtype of dementia, the ratio of male to female prevalence differs. For example, females are at greater risk of developing Alzheimer disease dementia, whereas males are at greater risk of developing vascular dementia. This review examines sex and gender differences in the development of dementia with the goal of highlighting factors that require further investigation. Considering sex as a biological variable in dementia research promises to advance our understanding of the pathophysiology and treatment of these conditions.
Considering sex and gender in Alzheimer disease and other dementias
Podcasy, Jessica L.; Epperson, C. Neill
2016-01-01
Suffering related to dementia is multifaceted because cognitive and physical functioning slowly deteriorates. Advanced age and sex, two of the most prominent risk factors for dementia, are not modifiable. Lifestyle factors such as smoking, excessive alcohol use, and poor diet modulate susceptibility to dementia in both males and females. The degree to which the resulting health conditions (eg, obesity, type 2 diabetes, and cardiovascular disease) impact dementia risk varies by sex. Depending on the subtype of dementia, the ratio of male to female prevalence differs. For example, females are at greater risk of developing Alzheimer disease dementia, whereas males are at greater risk of developing vascular dementia. This review examines sex and gender differences in the development of dementia with the goal of highlighting factors that require further investigation. Considering sex as a biological variable in dementia research promises to advance our understanding of the pathophysiology and treatment of these conditions. PMID:28179815
Sex hormones in early infancy seem to predict aspects of later language development.
Schaadt, Gesa; Hesse, Volker; Friederici, Angela D
2015-02-01
Sex differences in the development of cognitive behavior such as language have long been of great research interest. Lately, researchers have started to associate language function and brain differences with diverse sex hormones (e.g., testosterone/estradiol). However, results concerning the impact of early postnatal sex hormone concentration on the child's later language development are rare. Here, we analyze the impact of testosterone and estradiol in girls and boys as well as their neurophysiological phonemic discrimination at age 5months on language development at age 4years. Interestingly, we found strong positive estradiol and negative testosterone impact on later language performance at age 4years, which was true for both girls and boys. These results demonstrate that postnatal sex hormone surge might be viewed as one factor determining later language development, independent of gender. Copyright © 2014 Elsevier Inc. All rights reserved.
The Human Pelvis: Variation in Structure and Function During Gait.
Lewis, Cara L; Laudicina, Natalie M; Khuu, Anne; Loverro, Kari L
2017-04-01
The shift to habitual bipedalism 4-6 million years ago in the hominin lineage created a morphologically and functionally different human pelvis compared to our closest living relatives, the chimpanzees. Evolutionary changes to the shape of the pelvis were necessary for the transition to habitual bipedalism in humans. These changes in the bony anatomy resulted in an altered role of muscle function, influencing bipedal gait. Additionally, there are normal sex-specific variations in the pelvis as well as abnormal variations in the acetabulum. During gait, the pelvis moves in the three planes to produce smooth and efficient motion. Subtle sex-specific differences in these motions may facilitate economical gait despite differences in pelvic structure. The motions of the pelvis and hip may also be altered in the presence of abnormal acetabular structure, especially with acetabular dysplasia. Anat Rec, 300:633-642, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.
Gotoh, Hiroki; Zinna, Robert A; Warren, Ian; DeNieu, Michael; Niimi, Teruyuki; Dworkin, Ian; Emlen, Douglas J; Miura, Toru; Lavine, Laura C
2016-03-22
Genes in the sex determination pathway are important regulators of sexually dimorphic animal traits, including the elaborate and exaggerated male ornaments and weapons of sexual selection. In this study, we identified and functionally analyzed members of the sex determination gene family in the golden metallic stag beetle Cyclommatus metallifer, which exhibits extreme differences in mandible size between males and females. We constructed a C. metallifer transcriptomic database from larval and prepupal developmental stages and tissues of both males and females. Using Roche 454 pyrosequencing, we generated a de novo assembled database from a total of 1,223,516 raw reads, which resulted in 14,565 isotigs (putative transcript isoforms) contained in 10,794 isogroups (putative identified genes). We queried this database for C. metallifer conserved sex determination genes and identified 14 candidate sex determination pathway genes. We then characterized the roles of several of these genes in development of extreme sexual dimorphic traits in this species. We performed molecular expression analyses with RT-PCR and functional analyses using RNAi on three C. metallifer candidate genes--Sex-lethal (CmSxl), transformer-2 (Cmtra2), and intersex (Cmix). No differences in expression pattern were found between the sexes for any of these three genes. In the RNAi gene-knockdown experiments, we found that only the Cmix had any effect on sexually dimorphic morphology, and these mimicked the effects of Cmdsx knockdown in females. Knockdown of CmSxl had no measurable effects on stag beetle phenotype, while knockdown of Cmtra2 resulted in complete lethality at the prepupal period. These results indicate that the roles of CmSxl and Cmtra2 in the sex determination cascade are likely to have diverged in stag beetles when compared to Drosophila. Our results also suggest that Cmix has a conserved role in this pathway. In addition to those three genes, we also performed a more complete functional analysis of the C. metallifer dsx gene (Cmdsx) to identify the isoforms that regulate dimorphism more fully using exon-specific RNAi. We identified a total of 16 alternative splice variants of the Cmdsx gene that code for up to 14 separate exons. Despite the variation in RNA splice products of the Cmdsx gene, only four protein isoforms are predicted. The results of our exon-specific RNAi indicated that the essential CmDsx isoform for postembryonic male differentiation is CmDsxB, whereas postembryonic female specific differentiation is mainly regulated by CmDsxD. Taken together, our results highlight the importance of studying the function of highly conserved sex determination pathways in numerous insect species, especially those with dramatic and exaggerated sexual dimorphism, because conservation in protein structure does not always translate into conservation in downstream function.
Functional neuroimaging of sex differences in autobiographical memory recall.
Young, Kymberly D; Bellgowan, Patrick S F; Bodurka, Jerzy; Drevets, Wayne C
2013-12-01
Autobiographical memory (AM) is episodic memory for personally experienced events. The brain areas underlying AM retrieval are known to include several prefrontal cortical and medial temporal lobe regions. Sex differences in AM recall have been reported in several behavioral studies, but the functional anatomical correlates underlying such differences remain unclear. This study used fMRI to compare the neural correlates of AM recall between healthy male and female participants (n = 20 per group). AM recall in response to positive, negative, and neutral cue words was compared to a semantic memory task involving the generation of examples from a category using emotionally valenced cues. Behaviorally, females recalled more negative and fewer positive AMs compared with males, while ratings of arousal, vividness, and memory age did not differ significantly between sexes. Males and females also did not differ significantly in their performance on control tasks. Neurophysiologically, females showed increased hemodynamic activity compared to males in the dorsolateral prefrontal cortex (DLPFC), dorsal anterior insula, and precuneus while recalling specific AMs (all valences combined); increased activity in the DLPFC, transverse temporal gyrus, and precuneus while recalling positive AMs; and increased activity in the anterior cingulate cortex, precuneus, amygdala, and temporopolar cortex when recalling negative AMs. When comparing positive to negative AMs directly, males and females differed in their BOLD responses in the hippocampus and DLPFC. We propose that the differential hemodynamic changes may reflect sex-specific cognitive strategies during recall of AMs irrespective of the phenomenological properties of those memories. Copyright © 2012 Wiley Periodicals, Inc.
Wang, Jing-Jing; Chen, Tzu-An; Baranowski, Tom; Lau, Patrick W C
2017-09-16
This study aimed to evaluate the psychometric properties of four self-efficacy scales (i.e., self-efficacy for fruit (FSE), vegetable (VSE), and water (WSE) intakes, and physical activity (PASE)) and to investigate their differences in item functioning across sex, age, and body weight status groups using item response modeling (IRM) and differential item functioning (DIF). Four self-efficacy scales were administrated to 763 Hong Kong Chinese children (55.2% boys) aged 8-13 years. Classical test theory (CTT) was used to examine the reliability and factorial validity of scales. IRM was conducted and DIF analyses were performed to assess the characteristics of item parameter estimates on the basis of children's sex, age and body weight status. All self-efficacy scales demonstrated adequate to excellent internal consistency reliability (Cronbach's α: 0.79-0.91). One FSE misfit item and one PASE misfit item were detected. Small DIF were found for all the scale items across children's age groups. Items with medium to large DIF were detected in different sex and body weight status groups, which will require modification. A Wright map revealed that items covered the range of the distribution of participants' self-efficacy for each scale except VSE. Several self-efficacy scales' items functioned differently by children's sex and body weight status. Additional research is required to modify the four self-efficacy scales to minimize these moderating influences for application.
Löfvander, Monica; Rosenblad, Andreas; Wiklund, Tony; Bennström, Halina; Leppert, Jerzy
2014-12-01
To examine whether new immigrants had inferior quality-of-life, well-being and general functioning compared with Swedish age- and sex-matched controls. A prospective case-control study was designed including immigrants from non-European countries, 18-65 years of age, with recent Permanent Permits to Stay (PPS) in Sweden, and age- and sex-matched Swedish-born (SB) persons from the general population in Västmanland County, Sweden. The General Health Questionnaire (GHQ-12), the brief version of the World Health Organization Quality-of-Life (WHOQOL-BREF) Scale and the General Activity Functioning Assessment Scale (GAF) from DSM-IV were posted (SB), or applied in personal interviews (PPS) with interpreters. Differences between the PPS and SB groups were measured using McNemar's test and Wilcoxon signed-rank test conducted separately for observations at baseline, 6- and 12-month follow-up. There were 93 pairs (mean age 36 years). Persons from Somalia (67%) and Iraq (27%) dominated the PPS group. The differences between the groups were statistically significant for all time points for the Psychological health and Social relationship domains of WHOQOL-BREF, and for the baseline and 6-month follow-up time points of GHQ-12 where the PPS-group had a higher degree of well-being, health and quality-of-life than the SB. This tendency applied for both sexes in the immigrant group. These new immigrants did not have inferior physical or psychological health, quality-of-life, well-being or social functioning compared with their age- and sex-matched Swedish born pairs during a 1-year follow-up. Thus, there is reason to advocate immigrants' fast integration into society. © 2014 the Nordic Societies of Public Health.
Shen, Erica Y.; Ahern, Todd H.; Cheung, Iris; Straubhaar, Juerg; Dincer, Aslihan; Houston, Isaac; de Vries, Geert J.; Akbarian, Schahram; Forger, Nancy G.
2014-01-01
Many neurological and psychiatric disorders exhibit gender disparities, and sex differences in the brain likely explain some of these effects. Recent work in rodents points to a role for epigenetics in the development or maintenance of neural sex differences, although genome-wide studies have so far been lacking. Here we review the existing literature on epigenetics and brain sexual differentiation and present preliminary analyses on the genome-wide distribution of histone-3 lysine-4 trimethylation in a sexually dimorphic brain region in male and female mice. H3K4me3 is a histone mark primarily organized as ‘peaks’ surrounding the transcription start site of active genes. We microdissected the bed nucleus of the stria terminalis and preoptic area (BNST/POA) in adult male and female mice and used ChIP-Seq to compare the distribution of H3K4me3 throughout the genome. We found 248 genes and loci with a significant sex difference in H3K4me3. Of these, the majority (71%) had larger H3K4me3 peaks in females. Comparisons with existing databases indicate that genes and loci with increased H3K4me3 in females are associated with synaptic function and with expression atlases from related brain areas. Based on RT-PCR, only a minority of genes with a sex difference in H3K4me3 has detectable sex differences in expression at baseline conditions. Together with previous findings, our data suggest there may be sex biases in the use of epigenetic marks. Such biases could underlie sex differences in vulnerabilities to drugs or diseases that disrupt specific epigenetic processes. PMID:25131640
van der Plas, Ellen A A; Crone, Eveline A; van den Wildenberg, Wery P M; Tranel, Daniel; Bechara, Antoine
2009-08-01
Substance dependence is associated with executive function deficits, but the nature of these executive defects and the effect that different drugs and sex have on these defects have not been fully clarified. Therefore, we compared the performance of alcohol- (n = 33; 18 women), cocaine- (n = 27; 14 women), and methamphetamine-dependent individuals (n = 38; 25 women) with sex-matched healthy comparisons (n = 36; 17 women) on complex decision making as measured with the Iowa Gambling Task, working memory, cognitive flexibility, and response inhibition. Cocaine- and methamphetamine-dependent individuals were impaired on complex decision making, working memory, and cognitive flexibility, but not on response inhibition. The deficits in working memory and cognitive flexibility were milder than the decision-making deficits and did not change as a function of memory load or task switching. Interestingly, decision making was significantly more impaired in women addicted to cocaine or methamphetamine than in men addicted to these drugs. Together, these findings suggest that drug of choice and sex have different effects on executive functioning, which, if replicated, may help tailor intervention.
Cognition in Males and Females with Autism: Similarities and Differences
Lai, Meng-Chuan; Lombardo, Michael V.; Ruigrok, Amber N. V.; Chakrabarti, Bhismadev; Wheelwright, Sally J.; Auyeung, Bonnie; Allison, Carrie; Baron-Cohen, Simon
2012-01-01
The male bias in autism spectrum conditions (ASC) has led to females with ASC being under-researched. This lack of attention to females could hide variability due to sex that may explain some of the heterogeneity within ASC. In this study we investigate four key cognitive domains (mentalizing and emotion perception, executive function, perceptual attention to detail, and motor function) in ASC, to test for similarities and differences between males and females with and without ASC (n = 128 adults; n = 32 per group). In the mentalizing and facial emotion perception domain, males and females with ASC showed similar deficits compared to neurotypical controls. However, in attention to detail and dexterity involving executive function, although males with ASC showed poorer performance relative to neurotypical males, females with ASC performed comparably to neurotypical females. We conclude that performance in the social-cognitive domain is equally impaired in male and female adults with ASC. However, in specific non-social cognitive domains, performance within ASC depends on sex. This suggests that in specific domains, cognitive profiles in ASC are modulated by sex. PMID:23094036
Sex differences in impulsivity: a meta-analysis.
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.
Lateralized sex differences in stress-induced dopamine release in the rat.
Sullivan, Ron M; Dufresne, Marc M; Waldron, Jay
2009-02-18
This study examined the possibility that hemispheric differences in stress-induced brain activation vary as a function of sex. Using in-vivo voltammetry, increases in extracellular dopamine release in response to predator odour and tail pinch stress were recorded bilaterally and simultaneously in either the infralimbic cortex or basolateral amygdala. In both stress-sensitive brain regions, significant sex x hemisphere interactions were observed, with males and females showing greater dopamine activation in right-brain and left-brain structures, respectively. Cortical asymmetries in dopamine release also showed sex-specific correlations with stress-induced neuroendocrine activation. Given the intriguing human parallels, we suggest that differential cerebral lateralization may be highly relevant to the disproportionately high incidence of stress-related disorders such as depression and anxiety seen in women.
Spatiotemporal mapping of sex differences during attentional processing.
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/gender differences in the brain and cognition in schizophrenia.
Mendrek, Adrianna; Mancini-Marïe, Adham
2016-08-01
The early conceptualizations of schizophrenia have noted some sex/gender differences in epidemiology and clinical expression of the disorder. Over the past few decades, the interest in differences between male and female patients has expanded to encompass brain morphology and neurocognitive function. Despite some variability and methodological shortcomings, a few patterns emerge from the available literature. Most studies of gross neuroanatomy show more enlarged ventricles and smaller frontal lobes in men than in women with schizophrenia; finding reflecting normal sexual dimorphism. In comparison, studies of brain asymmetry and specific corticolimbic structures, suggest a disturbance in normal sexual dimorphism. The neurocognitive findings are somewhat consistent with this picture. Studies of cognitive functions mediated by the lateral frontal network tend to show sex differences in patients which are in the same direction as those observed in the general population, whereas studies of processes mediated by the corticolimbic system more frequently reveal reversal of normal sexual dimorphisms. These trends are faint and future research would need to delineate neurocognitive differences between men and women with various subtypes of schizophrenia (e.g., early versus late onset), while taking into consideration hormonal status and gender of tested participants. Copyright © 2015 Elsevier Ltd. All rights reserved.
Smith, David V.; Utevsky, Amanda V.; Bland, Amy R.; Clement, Nathan; Clithero, John A.; Harsch, Anne E. W.; Carter, R. McKell; Huettel, Scott A.
2014-01-01
A central challenge for neuroscience lies in relating inter-individual variability to the functional properties of specific brain regions. Yet, considerable variability exists in the connectivity patterns between different brain areas, potentially producing reliable group differences. Using sex differences as a motivating example, we examined two separate resting-state datasets comprising a total of 188 human participants. Both datasets were decomposed into resting-state networks (RSNs) using a probabilistic spatial independent components analysis (ICA). We estimated voxelwise functional connectivity with these networks using a dual-regression analysis, which characterizes the participant-level spatiotemporal dynamics of each network while controlling for (via multiple regression) the influence of other networks and sources of variability. We found that males and females exhibit distinct patterns of connectivity with multiple RSNs, including both visual and auditory networks and the right frontal-parietal network. These results replicated across both datasets and were not explained by differences in head motion, data quality, brain volume, cortisol levels, or testosterone levels. Importantly, we also demonstrate that dual-regression functional connectivity is better at detecting inter-individual variability than traditional seed-based functional connectivity approaches. Our findings characterize robust—yet frequently ignored—neural differences between males and females, pointing to the necessity of controlling for sex in neuroscience studies of individual differences. Moreover, our results highlight the importance of employing network-based models to study variability in functional connectivity. PMID:24662574
Lin, Hui-Jun; Viswanath, Kotapati Kasi; Lin, Chih-Peng; Chang, Bill Chia-Han; Chiu, Pei-Hsun; Chiu, Chan-Tai; Wang, Ren-Huang; Chin, Shih-Wen; Chen, Fure-Chyi
2018-01-01
Carica papaya L. is an important economic crop worldwide and is used as a model plant for sex-determination research. To study the different flower sex types, we screened sex-related genes using alternative splicing sequences (AS-seqs) from a transcriptome database of the three flower sex types, i.e., males, females, and hermaphrodites, established at 28 days before flowering using 15 bacterial artificial chromosomes (BACs) of C. papaya L. After screening, the cDNA regions of the three sex-related loci, including short vegetative phase-like (CpSVPL), the chromatin assembly factor 1 subunit A-like (CpCAF1AL), and the somatic embryogenesis receptor kinase (CpSERK), which contained eight sex-related single-nucleotide polymorphisms (SNPs) from the different sex types of C. papaya L., were genotyped using high-resolution melting (HRM). The three loci were examined regarding the profiles of the third whorl, as described below. CpSVPL, which had one SNP associated with the three sex genotypes, was highly expressed in the male and female sterile flowers (abnormal hermaphrodite flowers) that lacked the fourth whorl structure. CpCAF1AL, which had three SNPs associated with the male genotype, was highly expressed in male and normal hermaphrodite flowers, and had no AS-seqs, whereas it exhibited low expression and an AS-seqs in intron 11 in abnormal hermaphrodite flowers. Conversely, carpellate flowers (abnormal hermaphrodite flowers) showed low expression of CpSVPL and AS-seqs in introns 5, 6, and 7 of CpSERK, which contained four SNPs associated with the female genotype. Specifically, the CpSERK and CpCAF1AL loci exhibited no AS-seq expression in the third whorl of the male and normal hermaphrodite flowers, respectively, and variance in the AS-seq expression of all other types of flowers. Functional mapping of the third whorl of normal hermaphrodites indicated no AS-seq expression in CpSERK, low CpSVPL expression, and, for CpCAF1AL, high expression and no AS-seq expression on XYh-type chromosomes. PMID:29566053
ERIC Educational Resources Information Center
Vigil, Jacob M.; Geary, David C.; Granger, Douglas A.; Flinn, Mark V.
2010-01-01
The study examines group and individual differences in psychological functioning and hypothalamic-pituitary-adrenal and sympathetic nervous system (SNS) activity among adolescents displaced by Hurricane Katrina and living in a U.S. government relocation camp (n = 62, ages 12-19 years) 2 months postdisaster. Levels of salivary cortisol, salivary…
Mackiewicz, Kristen L; Sarinopoulos, Issidoros; Cleven, Krystal L; Nitschke, Jack B
2006-09-19
Prior research has shown memory is enhanced for emotional events. Key brain areas involved in emotional memory are the amygdala and hippocampus, which are also recruited during aversion and its anticipation. This study investigated whether anticipatory processes signaling an upcoming aversive event contribute to emotional memory. In an event-related functional MRI paradigm, 40 healthy participants viewed aversive and neutral pictures preceded by predictive warning cues. Participants completed a surprise recognition task directly after functional MRI scanning or 2 weeks later. In anticipation of aversive pictures, bilateral dorsal amygdala and anterior hippocampus activations were associated with better immediate recognition memory. Similar associations with memory were observed for activation of those areas in response to aversive pictures. Anticipatory activation predicted immediate memory over and above these associations for picture viewing. Bilateral ventral amygdala activations in response to aversive pictures predicted delayed memory only. We found that previously reported sex differences of memory associations with left amygdala for women and with right amygdala for men were confined to the ventral amygdala during picture viewing and delayed memory. Results support an established animal model elucidating the functional neuroanatomy of the amygdala and hippocampus in emotional memory, highlight the importance of anticipatory processes in such memory for aversive events, and extend neuroanatomical evidence of sex differences for emotional memory.
Vigil, Jacob M; Rowell, Lauren N; Chouteau, Simone; Chavez, Alexandre; Jaramillo, Elisa; Neal, Michael; Waid, David
2013-01-01
This is the first study to examine how both structural and functional components of individuals' social networks may moderate the association between biological sex and experimental pain sensitivity. One hundred and fifty-two healthy adults (mean age = 22yrs., 53% males) were measured for cold pressor task (CPT) pain sensitivity (i.e., intensity ratings) and core aspects of social networks (e.g., proportion of friends vs. family, affection, affirmation, and aid). Results showed consistent sex differences in how social network structures and intimate relationship functioning modulated pain sensitivity. Females showed higher pain sensitivity when their social networks consisted of a higher proportion of intimate types of relationship partners (e.g., kin vs. non kin), when they had known their network partners for a longer period of time, and when they reported higher levels of logistical support from their significant other (e.g., romantic partner). Conversely, males showed distinct patterns in the opposite direction, including an association between higher levels of logistical support from one's significant other and lower CPT pain intensity. These findings show for the first time that the direction of sex differences in exogenous pain sensitivity is likely dependent on fundamental components of the individual's social environment. The utility of a social-signaling perspective of pain behaviors for examining, comparing, and interpreting individual and group differences in experimental and clinical pain reports is discussed.
Hardee, Jillian E; Cope, Lora M; Munier, Emily C; Welsh, Robert C; Zucker, Robert A; Heitzeg, Mary M
2017-06-01
There is substantial evidence for behavioral sex differences in risk trajectories for alcohol and substance use, with internalizing factors such as negative affectivity contributing more to female risk. Because the neural development of emotion circuitry varies between males and females across adolescence, it represents a potential mechanism by which underlying neurobiology contributes to risk for substance use. Longitudinal functional magnetic resonance imaging was conducted in males and females (n = 18 each) with a family history of alcohol use disorders starting at ages 8-13 years. Participants performed an affective word task during functional magnetic resonance imaging at 1- to 2-year intervals, covering the age range of 8.5-17.6 years (3-4 scans per participant). Significant age-related sex differences were found in the right amygdala and right precentral gyrus for the negative vs neutral word condition. Males showed a significant decrease in both amygdala and precentral gyrus activation with age, whereas the response in females persisted. The subjective experience of internalizing symptomatology significantly increased with age for females but not for males. Taken together, these results reveal sex differences in negative affect processing in at-risk adolescents, and offer longitudinal neural evidence for female substance use risk through internalizing pathways. © The Author (2017). Published by Oxford University Press.
Darda, Kohinoor M; Butler, Emily E; Ramsey, Richard
2018-06-01
Humans show an involuntary tendency to copy other people's actions. Although automatic imitation builds rapport and affiliation between individuals, we do not copy actions indiscriminately. Instead, copying behaviors are guided by a selection mechanism, which inhibits some actions and prioritizes others. To date, the neural underpinnings of the inhibition of automatic imitation and differences between the sexes in imitation control are not well understood. Previous studies involved small sample sizes and low statistical power, which produced mixed findings regarding the involvement of domain-general and domain-specific neural architectures. Here, we used data from Experiment 1 ( N = 28) to perform a power analysis to determine the sample size required for Experiment 2 ( N = 50; 80% power). Using independent functional localizers and an analysis pipeline that bolsters sensitivity, during imitation control we show clear engagement of the multiple-demand network (domain-general), but no sensitivity in the theory-of-mind network (domain-specific). Weaker effects were observed with regard to sex differences, suggesting that there are more similarities than differences between the sexes in terms of the neural systems engaged during imitation control. In summary, neurocognitive models of imitation require revision to reflect that the inhibition of imitation relies to a greater extent on a domain-general selection system rather than a domain-specific system that supports social cognition.
Vigil, Jacob M.; Rowell, Lauren N.; Chouteau, Simone; Chavez, Alexandre; Jaramillo, Elisa; Neal, Michael; Waid, David
2013-01-01
This is the first study to examine how both structural and functional components of individuals’ social networks may moderate the association between biological sex and experimental pain sensitivity. One hundred and fifty-two healthy adults (mean age = 22yrs., 53% males) were measured for cold pressor task (CPT) pain sensitivity (i.e., intensity ratings) and core aspects of social networks (e.g., proportion of friends vs. family, affection, affirmation, and aid). Results showed consistent sex differences in how social network structures and intimate relationship functioning modulated pain sensitivity. Females showed higher pain sensitivity when their social networks consisted of a higher proportion of intimate types of relationship partners (e.g., kin vs. non kin), when they had known their network partners for a longer period of time, and when they reported higher levels of logistical support from their significant other (e.g., romantic partner). Conversely, males showed distinct patterns in the opposite direction, including an association between higher levels of logistical support from one’s significant other and lower CPT pain intensity. These findings show for the first time that the direction of sex differences in exogenous pain sensitivity is likely dependent on fundamental components of the individual’s social environment. The utility of a social-signaling perspective of pain behaviors for examining, comparing, and interpreting individual and group differences in experimental and clinical pain reports is discussed. PMID:24223836
Wu, Yili; Pang, Zengchang; Zhang, Dongfeng; Jiang, Wenjie; Wang, Shaojie; Li, Shuxia; Kruse, Torben A; Christensen, Kaare; Tan, Qihua
2012-01-01
By focusing on four health variables, handgrip strength, near visual acuity, tooth loss and hearing level, this study examined the different patterns of age-related changes in these variables in Chinese aged from 50 to 74 years, as well as explored the relationship among the variables in a cross-sectional sample of 2006 individuals. The data exhibited high quality with a low missing rate of under 5% in any age groups for each variable. Effects of age and sex on the changes in the four health variables were assessed using multiple regression models with age and sex interactions included. Upon the highly significant effects of age on all four measurements, we observed substantially higher grip strength for men who, however, exhibited a faster age-related decline than for women. No sex difference or age-sex interaction was found in the number of teeth lost. Near visual acuity displayed a faster age-related decline in women than in men but neither the overall sex difference nor age-sex interaction reached statistical significance. For hearing function, while no sex difference was found at middle frequency, women had better sensitivity at high frequency and men were more sensitive at low frequency. Multivariate analysis did not support an age-related common mechanism underlying the four health variables. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.
Peers Influence Mathematics Strategy Use in Early Elementary School
ERIC Educational Resources Information Center
Carr, Martha; Barned, Nicole; Otumfuor, Beryl
2016-01-01
This study examined the impact of performance goals on arithmetic strategy use, and how same-sex peer groups contributed to the selection of strategies used by first-graders. It was hypothesized that gender differences in strategy use are a function of performance goals and the influence of same-sex peers. Using a sample of 75 first grade…
Etiology of Reading Difficulties as a Function of Gender and Severity
ERIC Educational Resources Information Center
Hawke, Jesse L.; Wadsworth, Sally J.; Olson, Richard K.; DeFries, John C.
2007-01-01
To test the hypothesis that the etiology of reading difficulties may differ for males and females in more severely impaired samples, reading performance data from monozygotic (MZ), same-sex dizygotic (DZ[subscript ss]), and opposite-sex dizygotic (DZ[subscript os]) twin pairs were analyzed using a model-fitting implementation of the DeFries-Fulker…
Roved, Jacob; Westerdahl, Helena; Hasselquist, Dennis
2017-02-01
Males and females differ in both parasite load and the strength of immune responses and these effects have been verified in humans and other vertebrates. Sex hormones act as important modulators of immune responses; the male sex hormone testosterone is generally immunosuppressive while the female sex hormone estrogen tends to be immunoenhancing. Different sets of T-helper cells (Th) have important roles in adaptive immunity, e.g. Th1 cells trigger type 1 responses which are primarily cell-mediated, and Th2 cells trigger type 2 responses which are primarily humoral responses. In our review of the literature, we find that estrogen and progesterone enhance type 2 and suppress type 1 responses in females, whereas testosterone suppresses type 2 responses and shows an inconsistent pattern for type 1 responses in males. When we combine these patterns of generally immunosuppressive and immunoenhancing effects of the sex hormones, our results imply that the sex differences in immune responses should be particularly strong in immune functions associated with type 2 responses, and less pronounced with type 1 responses. In general the hormone-mediated sex differences in immune responses may lead to genetic sexual conflicts on immunity. Thus, we propose the novel hypothesis that sexually antagonistic selection may act on immune genes shared by the sexes, and that the strength of this sexually antagonistic selection should be stronger for type 2- as compared with type 1-associated immune genes. Finally, we put the consequences of sex hormone-induced effects on immune responses into behavioral and ecological contexts, considering social mating system, sexual selection, geographical distribution of hosts, and parasite abundance. Copyright © 2016 Elsevier Inc. All rights reserved.
Cain, Virginia S; Johannes, Catherine B; Avis, Nancy E; Mohr, Beth; Schocken, Miriam; Skurnick, Joan; Ory, Marcia
2003-08-01
This study examined the sexual practices and function of midlife women by ethnicity (African American, Caucasian, Chinese, Hispanic, Japanese) and menopausal status. Sexual behavior was compared in 3,262 women in the baseline cohort of SWAN. Participants were 42 to 52 years old, premenopausal or early perimenopausal, and not hysterectomized or using hormones. Analysis used multivariate proportional odds regression. In our sample, 79% had engaged in sex with a partner in the last 6 months, and a third considered sex to be very important. Common reasons for no sex (n = 676) were lack of partner (67%), lack of interest (33%), and fatigue (16%). Compared with Caucasians, Japanese and Chinese women were less likely, and African Americans more likely, to report sex as very important (p < 0.005). Significant ethnic differences were found for frequency of all practices. Perimenopause status was associated only with higher frequencies of masturbation and pain during intercourse.
Neurobehavioral Deficits Consistent Across Age and Sex in Youth with Prenatal Alcohol Exposure.
Panczakiewicz, Amy L; Glass, Leila; Coles, Claire D; Kable, Julie A; Sowell, Elizabeth R; Wozniak, Jeffrey R; Jones, Kenneth Lyons; Riley, Edward P; Mattson, Sarah N
2016-09-01
Neurobehavioral consequences of heavy prenatal alcohol exposure are well documented; however, the role of age or sex in these effects has not been studied. The current study examined the effects of prenatal alcohol exposure, sex, and age on neurobehavioral functioning in children. Subjects were 407 youth with prenatal alcohol exposure (n = 192) and controls (n = 215). Two age groups (child [5 to 7 years] or adolescent [10 to 16 years]) and both sexes were included. All subjects completed standardized neuropsychological testing, and caregivers completed parent-report measures of psychopathology and adaptive behavior. Neuropsychological functioning, psychopathology, and adaptive behavior were analyzed with separate 2 (exposure history) × 2 (sex) × 2 (age) multivariate analyses of variance (MANOVAs). Significant effects were followed by univariate analyses. No 3-way or 2-way interactions were significant. The main effect of group was significant in all 3 MANOVAs, with the control group performing better than the alcohol-exposed group on all measures. The main effect of age was significant for neuropsychological performance and adaptive functioning across exposure groups with younger children performing better than older children on 3 measures (language, communication, socialization). Older children performed better than younger children on a different language measure. The main effect of sex was significant for neuropsychological performance and psychopathology; across exposure groups, males had stronger language and visual spatial scores and fewer somatic complaints than females. Prenatal alcohol exposure resulted in impaired neuropsychological and behavioral functioning. Although adolescents with prenatal alcohol exposure may perform more poorly than younger exposed children, the same was true for nonexposed children. Thus, these cross-sectional data indicate that the developmental trajectory for neuropsychological and behavioral performance is not altered by prenatal alcohol exposure, but rather, deficits are consistent across the 2 age groups tested. Similarly, observed sex differences on specific measures were consistent across the groups and do not support sexually dimorphic effects in these domains. Copyright © 2016 by the Research Society on Alcoholism.
Santolaria, Pilar; Pauciullo, Alfredo; Silvestre, Miguel A; Vicente-Fiel, Sandra; Villanova, Leyre; Pinton, Alain; Viruel, Juan; Sales, Ester; Yániz, Jesús L
2016-01-01
This study was designed to determine the ability of computer-assisted sperm morphometry analysis (CASA-Morph) with fluorescence to discriminate between spermatozoa carrying different sex chromosomes from the nuclear morphometrics generated and different statistical procedures in the bovine species. The study was divided into two experiments. The first was to study the morphometric differences between X- and Y-chromosome-bearing spermatozoa (SX and SY, respectively). Spermatozoa from eight bulls were processed to assess simultaneously the sex chromosome by FISH and sperm morphometry by fluorescence-based CASA-Morph. SX cells were larger than SY cells on average (P < 0.001) although with important differences between bulls. A simultaneous evaluation of all the measured features by discriminant analysis revealed that nuclear area and average fluorescence intensity were the variables selected by stepwise discriminant function analysis as the best discriminators between SX and SY. In the second experiment, the sperm nuclear morphometric results from CASA-Morph in nonsexed (mixed SX and SY) and sexed (SX) semen samples from four bulls were compared. FISH allowed a successful classification of spermatozoa according to their sex chromosome content. X-sexed spermatozoa displayed a larger size and fluorescence intensity than nonsexed spermatozoa (P < 0.05). We conclude that the CASA-Morph fluorescence-based method has the potential to find differences between X- and Y-chromosome-bearing spermatozoa in bovine species although more studies are needed to increase the precision of sex determination by this technique.
Sex differences in the effect of puberty on hippocampal morphology.
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
2014-03-01
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. T1-weighted structural neuroimaging was performed in a sample of 524 pre- or postpubertal individuals ages 10 to 22 years. Hippocampal and amygdala volume and shape were quantified using the Functional Magnetic Resonance Imaging of the Brain (FMRIB) Software Library (FSL) 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. 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. 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. Copyright © 2014 American Academy of Child and Adolescent Psychiatry. Published by Elsevier Inc. All rights reserved.
Collaer, Marcia L; Hill, Erica M
2006-01-01
Visuospatial performance, assessed with the new, group-administered Judgment of Line Angle and Position test (JLAP-13), varied with sex and mathematical competence in a group of adolescents. The JLAP-13, a low-level perceptual task, was modeled after a neuropsychological task dependent upon functioning of the posterior region of the right hemisphere [Benton et al, 1994 Contributions to Neuropsychological Assessment: A Clinical Manual (New York: Oxford University Press)]. High-school boys (N = 52) performed better than girls (N = 62), with a large effect for sex (d = 1.11). Performance increased with mathematical competence, but the sex difference did not vary significantly across different levels of mathematics coursework. On the basis of earlier work, it was predicted that male, but not female, performance in line judgment would decline with disruptions to task geometry (page frame), and that the sex difference would disappear with disruptions to geometry. These predictions were supported by a number of univariate and sex-specific analyses, although an omnibus repeated-measures analysis did not detect the predicted interaction, most likely owing to limitations in power. Thus, there is partial support for the notion that attentional predispositions or strategies may contribute to visuospatial sex differences, with males more likely than females to attend to, and rely upon, internal or external representations of task geometry. Additional support for this hypothesis may require development of new measures or experimental manipulations with more powerful geometrical disruptions.
The Evolution of Sex Chromosomes and Dosage Compensation in Plants.
Muyle, Aline; Shearn, Rylan; Marais, Gabriel Ab
2017-03-01
Plant sex chromosomes can be vastly different from those of the few historical animal model organisms from which most of our understanding of sex chromosome evolution is derived. Recently, we have seen several advancements from studies on green algae, brown algae, and land plants that are providing a broader understanding of the variable ways in which sex chromosomes can evolve in distant eukaryotic groups. Plant sex-determining genes are being identified and, as expected, are completely different from those in animals. Species with varying levels of differentiation between the X and Y have been found in plants, and these are hypothesized to be representing different stages of sex chromosome evolution. However, we are also finding that sex chromosomes can remain morphologically unchanged over extended periods of time. Where degeneration of the Y occurs, it appears to proceed similarly in plants and animals. Dosage compensation (a phenomenon that compensates for the consequent loss of expression from the Y) has now been documented in a plant system, its mechanism, however, remains unknown. Research has also begun on the role of sex chromosomes in sexual conflict resolution, and it appears that sex-biased genes evolve similarly in plants and animals, although the functions of these genes remain poorly studied. Because the difficulty in obtaining sex chromosome sequences is increasingly being overcome by methodological developments, there is great potential for further discovery within the field of plant sex chromosome evolution. © The Author(s) 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.
Gotoh, Hiroki; Ishiguro, Mai; Nishikawa, Hideto; Morita, Shinichi; Okada, Kensuke; Miyatake, Takahisa; Yaginuma, Toshinobu; Niimi, Teruyuki
2016-01-01
Various types of weapon traits found in insect order Coleoptera are known as outstanding examples of sexually selected exaggerated characters. It is known that the sex determination gene doublesex (dsx) plays a significant role in sex-specific expression of weapon traits in various beetles belonging to the superfamily Scarabaeoidea. Although sex-specific weapon traits have evolved independently in various Coleopteran groups, developmental mechanisms of sex-specific expression have not been studied outside of the Scarabaeoidea. In order to test the hypothesis that dsx-dependent sex-specific expression of weapon traits is a general mechanism among the Coleoptera, we have characterized the dsx in the sexually dimorphic broad-horned beetle Gnatocerus cornutus (Tenebrionidea, Tenebirionidae). By using molecular cloning, we identified five splicing variants of Gnatocerus cornutus dsx (Gcdsx), which are predicted to code four different isoforms. We found one male-specific variant (GcDsx-M), two female-specific variants (GcDsx-FL and GcDsx-FS) and two non-sex-specific variants (correspond to a single isoform, GcDsx-C). Knockdown of all Dsx isoforms resulted in intersex phenotype both in male and female. Also, knockdown of all female-specific isoforms transformed females to intersex phenotype, while did not affect male phenotype. Our results clearly illustrate the important function of Gcdsx in determining sex-specific trait expression in both sexes. PMID:27404087
Jin, Jun-Yan; Li, Zhao-Qun; Zhang, Ya-Nan; Liu, Nai-Yong; Dong, Shuang-Lin
2014-07-01
Pheromone binding proteins (PBPs) are thought to bind and transport hydrophobic sex pheromone molecules across the aqueous sensillar lymph to specific pheromone receptors on the dendritic membrane of olfactory neurons. A maximum of 3 PBP genes have been consistently identified in noctuid species, and each of them shares high identity with its counterparts in other species within the family. The functionality differences of the 3 proteins are poorly understood. In the present study, 3 PBP cDNAs (SinfPBP1, 2, 3) were identified from the pink rice borer, Sesamia inferens, for the first time. The quantitative real-time PCR indicated that the 3 PBPs displayed similar temporal but very different sex related expression profiles. Expression of SinfPBP1 and SinfPBP2 were highly and moderately male biased, respectively, while SinfPBP3 was slightly female biased, as SinfPBPs were expressed at very different levels (PBP1>PBP2≫PBP3) in male antennae, but at similar levels in female antennae. Furthermore, the 3 SinfPBPs displayed different ligand binding profiles in fluorescence competitive binding assays. SinfPBP1 exhibited high and similar binding affinities to all 3 sex pheromone components (Ki=0.72-1.60 μM), while SinfPBP2 showed selective binding to the alcohol and aldehyde components (Ki=0.78-1.71 μM), and SinfPBP3 showed no obvious binding to the 3 sex pheromone components. The results suggest that SinfPBP1 plays a major role in the reception of female sex pheromones in S. inferens, while SinfPBP3 plays a least role (if any) and SinfPBP2 functions as a recognizer of alcohol and aldehyde components. Copyright © 2014 Elsevier Ltd. All rights reserved.
Sex differences in brain activation to emotional stimuli: a meta-analysis of neuroimaging studies.
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-analysis findings indicate that the amygdala, a key region for emotion processing, exhibits valence-dependent sex differences in activation to emotional stimuli. The greater left amygdala response to negative emotion for women accords with previous reports that women respond more strongly to negative emotional stimuli, as well as with hypothesized links between increased neurobiological reactivity to negative emotion and increased prevalence of depression and anxiety disorders in women. The finding of greater left amygdala activation for positive emotional stimuli in men suggests that greater amygdala responses reported previously for men for specific types of positive stimuli may also extend to positive stimuli more generally. In summary, this study extends efforts to characterize sex differences in brain activation during emotion processing by providing the largest and most comprehensive quantitative meta-analysis to date, and for the first time examining sex differences as a function of positive vs. negative emotional valence. The current findings highlight the importance of considering sex as a potential factor modulating emotional processing and its underlying neural mechanisms, and more broadly, the need to consider individual differences in understanding the neurobiology of emotion. Copyright © 2012 Elsevier Ltd. All rights reserved.
Chuang, Jie-Yu; Hagan, Cindy C; Murray, Graham K; Graham, Julia M E; Ooi, Cinly; Tait, Roger; Holt, Rosemary J; Elliott, Rebecca; van Nieuwenhuizen, Adrienne O; Bullmore, Edward T; Lennox, Belinda R; Sahakian, Barbara J; Goodyer, Ian M; Suckling, John
2017-01-01
Compared to female major depressive disorder (MDD), male MDD often receives less attention. However, research is warranted since there are significant sex differences in the clinical presentation of MDD and a higher rate of suicide in depressed men. To the best of our knowledge, this is the first functional magnetic resonance imaging (fMRI) study with a large sample addressing putative sex differences in MDD during adolescence, a period when one of the most robust findings in psychiatric epidemiology emerges; that females are twice as likely to suffer from MDD than males. Twenty-four depressed and 10 healthy male adolescents, together with 82 depressed and 24 healthy female adolescents, aged 11-18 years, undertook an affective go/no-go task during fMRI acquisition. In response to sad relative to neutral distractors, significant sex differences (in the supramarginal gyrus) and group-by-sex interactions (in the supramarginal gyrus and the posterior cingulate cortex) were found. Furthermore, in contrast to the healthy male adolescents, depressed male adolescents showed decreased activation in the cerebellum with a significant group-by-age interaction in connectivity. Future research may consider altered developmental trajectories and the possible implications of sex-specific treatment and prevention strategies for MDD.
Rigon, Arianna; Turkstra, Lyn; Mutlu, Bilge; Duff, Melissa
2018-01-01
Although moderate to severe traumatic brain injury (TBI) leads to facial affect recognition impairments in up to 39% of individuals, protective and risk factors for these deficits are unknown. The aim of the current study was to examine the effect of sex on emotion recognition abilities following TBI. We administered two separate emotion recognition tests (one static and one dynamic) to 53 individuals with moderate to severe TBI (Females=28) and 49 demographically matched comparisons (Females=22). We then investigated the presence of a sex-by-group interaction in emotion recognition accuracy. In the comparison group, there were no sex differences. In the TBI group, however, females significantly outperformed males in the dynamic (but not the static) task. Moreover, males (but not females) with TBI performed significantly worse than comparison participants in the dynamic task. Further analysis revealed that sex differences in emotion recognition abilities within the TBI group could not be explained by lesion location, TBI severity, or other neuropsychological variables. These findings suggest that sex may serve as a protective factor for social impairment following TBI and inform clinicians working with TBI as well as research on the neurophysiological correlates of sex differences in social functioning. PMID:27245826
Summer habitat selection by Dall’s sheep in Wrangell-St. Elias National Park and Preserve, Alaska
Roffler, Gretchen H.; Adams, Layne G.; Hebblewhite, Mark
2017-01-01
Sexual segregation occurs frequently in sexually dimorphic species, and it may be influenced by differential habitat requirements between sexes or by social or evolutionary mechanisms that maintain separation of sexes regardless of habitat selection. Understanding the degree of sex-specific habitat specialization is important for management of wildlife populations and the design of monitoring and research programs. Using mid-summer aerial survey data for Dall’s sheep (Ovis dalli dalli) in southern Alaska during 1983–2011, we assessed differences in summer habitat selection by sex and reproductive status at the landscape scale in Wrangell-St. Elias National Park and Preserve (WRST). Males and females were highly segregated socially, as were females with and without young. Resource selection function (RSF) models containing rugged terrain, intermediate values of the normalized difference vegetation index (NDVI), and open landcover types best explained resource selection by each sex, female reproductive classes, and all sheep combined. For male and all female models, most coefficients were similar, suggesting little difference in summer habitat selection between sexes at the landscape scale. A combined RSF model therefore may be used to predict the relative probability of resource selection by Dall’s sheep in WRST regardless of sex or reproductive status.
The Science of Sex Differences in Science and Mathematics
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 influences; training and experience; and cultural practices. We conclude that early experience, biological factors, educational policy, and cultural context affect the number of women and men who pursue advanced study in science and math and that these effects add and interact in complex ways. There are no single or simple answers to the complex questions about sex differences in science and mathematics. PMID:25530726
Tabasum, Qutsia; Sehrawat, Jagmahender Singh; Talwar, Manjit Kaur; Pathak, Raj Kamal
2017-01-01
Different dental features have contributed significantly toward sex determination in the forensic anthropological contexts. Population-specific standards (discriminant functions or regression formulae) have been suggested for various population groups to identify the sex of an unknown individual from dental dimensions and other odontometric features. The main purpose of the present investigation was to examine the degree of sexual dimorphism exhibited by the human teeth of North Indians and identify importance as a forensic tool in sex determination. The linear and diagonal dimensions were recorded at both crown and cementoenamel junction levels of 58 upper and 72 lower molars of 130 Northwest Indian subjects (73 males and 57 females). The measurements were subjected to appropriate statistical analyses to estimate the sex estimation accuracy from lower and upper molars separately. Univariate analyses revealed that molar teeth had greater dimensions in males than the females and the mesiodistal cervical diameter (MDCV) was found to be the most suitable variable for sex determination of the molars. The classification results were in agreement with the previously conducted studies. The index of sexual dimorphism (ISD) was calculated to be higher in lower molars than the upper molars, and the highest sex differences were observed for MDCV based on the ISD. The overall sex estimation accuracy obtained from multivariate discriminant function analysis and regression analysis of pooled data was 70.0% (74% males, 64.9% females) and 66.9% (78.1% males, 52.6% females), respectively. Odontometrics can play a significant role in establishing the biological identity of an unknown individual even from a single tooth in the absence of other sophisticated molecular or biochemical techniques used for this purpose.
Tabasum, Qutsia; Sehrawat, Jagmahender Singh; Talwar, Manjit Kaur; Pathak, Raj Kamal
2017-01-01
Background: Different dental features have contributed significantly toward sex determination in the forensic anthropological contexts. Population-specific standards (discriminant functions or regression formulae) have been suggested for various population groups to identify the sex of an unknown individual from dental dimensions and other odontometric features. The main purpose of the present investigation was to examine the degree of sexual dimorphism exhibited by the human teeth of North Indians and identify importance as a forensic tool in sex determination. Materials and Methods: The linear and diagonal dimensions were recorded at both crown and cementoenamel junction levels of 58 upper and 72 lower molars of 130 Northwest Indian subjects (73 males and 57 females). The measurements were subjected to appropriate statistical analyses to estimate the sex estimation accuracy from lower and upper molars separately. Results: Univariate analyses revealed that molar teeth had greater dimensions in males than the females and the mesiodistal cervical diameter (MDCV) was found to be the most suitable variable for sex determination of the molars. The classification results were in agreement with the previously conducted studies. The index of sexual dimorphism (ISD) was calculated to be higher in lower molars than the upper molars, and the highest sex differences were observed for MDCV based on the ISD. The overall sex estimation accuracy obtained from multivariate discriminant function analysis and regression analysis of pooled data was 70.0% (74% males, 64.9% females) and 66.9% (78.1% males, 52.6% females), respectively. Conclusions: Odontometrics can play a significant role in establishing the biological identity of an unknown individual even from a single tooth in the absence of other sophisticated molecular or biochemical techniques used for this purpose. PMID:29657498
Plante, D T; Goldstein, M R; Landsness, E C; Peterson, M J; Riedner, B A; Ferrarelli, F; Wanger, T; Guokas, J J; Tononi, G; Benca, R M
2013-03-20
Sleep spindles are believed to mediate several sleep-related functions including maintaining disconnection from the external environment during sleep, cortical development, and sleep-dependent memory consolidation. Prior studies that have examined sleep spindles in major depressive disorder (MDD) have not demonstrated consistent differences relative to control subjects, which may be due to sex-related variation and limited spatial resolution of spindle detection. Thus, this study sought to characterize sleep spindles in MDD using high-density electroencephalography (hdEEG) to examine the topography of sleep spindles across the cortex in MDD, as well as sex-related variation in spindle topography in the disorder. All-night hdEEG recordings were collected in 30 unipolar MDD participants (19 women) and 30 age and sex-matched controls. Topography of sleep spindle density, amplitude, duration, and integrated spindle activity (ISA) were assessed to determine group differences. Spindle parameters were compared between MDD and controls, including analysis stratified by sex. As a group, MDD subjects demonstrated significant increases in frontal and parietal spindle density and ISA compared to controls. When stratified by sex, MDD women demonstrated increases in frontal and parietal spindle density, amplitude, duration, and ISA; whereas MDD men demonstrated either no differences or decreases in spindle parameters. Given the number of male subjects, this study may be underpowered to detect differences in spindle parameters in male MDD participants. This study demonstrates topographic and sex-related differences in sleep spindles in MDD. Further research is warranted to investigate the role of sleep spindles and sex in the pathophysiology of MDD. Copyright © 2012 Elsevier B.V. All rights reserved.
Dumais, Kelly M; Franklin, Teresa R; Jagannathan, Kanchana; Hager, Nathan; Gawrysiak, Michael; Betts, Jennifer; Farmer, Stacey; Guthier, Emily; Pater, Heather; Janes, Amy C; Wetherill, Reagan R
2017-09-01
Biological sex influences cigarette smoking behavior. More men than women smoke, but women have a harder time quitting. Sex differences in smoking cue (SC) reactivity may underlie such behavioral differences. However, the influence of sex on brain reactivity to SCs has yielded inconsistent findings suggesting the need for continued study. Here, we investigated the effect of sex on SC reactivity across two sites using different imaging modalities and SC stimulus types. Pseudo-continuous arterial spin-labeled (pCASL) perfusion functional magnetic resonance imaging (fMRI) was used to assess brain responses to SC versus non-SC videos in 40 smokers (23 females) at the University of Pennsylvania. BOLD fMRI was used to assess brain responses to SC versus non-SC still images in 32 smokers (18 females) at McLean Hospital. Brain reactivity to SCs was compared between men and women and was correlated with SC-induced craving. In both cohorts, males showed higher SC versus non-SC reactivity compared to females in reward-related brain regions (i.e., ventral striatum/ventral pallidum, ventral medial prefrontal cortex). Brain activation during SC versus non-SC exposure correlated positively with SC-induced subjective craving in males, but not females. The current work provides much needed replication and validation of sex differences in SC-reactivity. These findings also add to a body of literature showing that men have greater reward-related brain activation to drug cues across drug classes. Such sex differences confirm the need to consider sex not only when evaluating SC-reactivity but when examining nicotine dependence etiology and treatment. Copyright © 2017 Elsevier B.V. All rights reserved.
Jayasena, Dinesh D.; Jung, Samooel; Alahakoon, Amali U.; Nam, Ki Chang
2014-01-01
Studies on the flavour characteristics of meat-based broth, quantification of flavour-related and functional compounds, and factors affecting the availability of such compounds are minimal. The present study was designed to determine the effects of sex on flavor-related and functional compounds in freeze-dried broth (FDB) made from Korean native chickens (KNC). Male and female KNC from a commercial strain (WoorimatdagTM) were reared under similar commercial conditions. FDB was separately prepared using male and female birds aged 100 d (six birds of each sex) and analyzed for nucleotide, free amino acid, betaine, carnitine, carnosine, anserine, and creatine contents, and fatty acid composition. The levels of betaine, carnitine and creatine in FDB were not significantly different between the two sexes (p>0.05) in KNC. Carnosine and anserine were not detected in FDB samples. However, FDB from female chickens had significantly higher inosine-5-monophosphate and arachidonic acid contents than did FDB from male chickens. FDB prepared with male KNC contained higher levels of inosine, linoleic acid, glycine, alanine, lysine, and serine (p<0.05). However, glutamic acid, oleic acid, and DHA were present in comparable amounts (p>0.05) in FDB made from male and female KNC. Our findings suggest that the sex of KNC has significant effect on the contents of flavor-related compounds, but not functional compounds. PMID:26761282
Kelsey, Megan M; Braffett, Barbara H; Geffner, Mitchell E; Levitsky, Lynne L; Caprio, Sonia; McKay, Siripoom V; Shah, Rachana; Sprague, Jennifer E; Arslanian, Silva A
2018-04-24
Little is known about reproductive function in girls with youth-onset type 2 diabetes. To characterize girls with irregular menses, and effects of glycemic treatments on menses and sex steroids in the Treatment Options for Type 2 Diabetes in Youth (TODAY) study. Differences in demographic, metabolic, and hormonal characteristics between regular vs. irregular menses groups were tested; treatment group (metformin +/- rosiglitazone, metformin + lifestyle) effect on menses and sex steroids over time in the study was assessed. This is a secondary analysis of TODAY data. Multi-center study in an academic setting. TODAY girls not on hormonal contraception and those > 1-year post-menarche were included. Irregular menses was defined as < 3 periods in the prior 6 months. Eligible participants with serum measurement of sex steroids (n=190, mean age 14 years), 21% had irregular menses. Those with irregular vs. regular menses had higher body mass index (BMI) (p=0.001), AST (p=0.001), free androgen index (p=0.0003), total testosterone (p=0.01); and lower sex-hormone binding globulin (SHBG) (p=0.004) and estradiol (p=0.01). Differences remained after adjusting for BMI. There was no treatment group effect on menses or sex steroids at 12 or 24 months, and no association of sex steroids with measures of insulin sensitivity or secretion. Menstrual dysfunction is common in girls with recently diagnosed T2D and associated with alterations in sex steroids, SHBG, and AST, but not with alteration in insulin sensitivity or β-cell function, and did not improve with 2 years of anti-hyperglycemic treatment.
Gurvich, C; Rossell, S L
2015-03-15
Cognitive performance in healthy persons varies widely between individuals. Sex differences in cognition are well reported, and there is an emerging body of evidence suggesting that the relationship between dopaminergic neurotransmission, implicated in many cognitive functions, is modulated by sex. Here, we examine the influence of sex and genetic variations along the dopaminergic pathway on aspects of cognitive control. A total of 415 healthy individuals, selected from an international consortium linked to Brain Research and Integrative Neuroscience Network (BRAINnet), were genotyped for two common and functional genetic variations of dopamine regulating genes: the catechol-O-methyltransferase [COMT] gene (rs4680) and the dopamine receptor D2 [DRD2] gene (rs6277). Cognitive measures were selected to explore sustained attention (using a continuous performance task), switching of attention (using a Trails B adaptation) and working memory (a visual computerised adaptation of digit span). While there were no main effects for genotype across any tasks, analyses revealed significant sex by genotype interactions for the capacity to switch attention. In relation to COMT, superior performance was noted in females with the Val/Val genotype and for DRD2, superior performance was seen for TT females and CC males. These findings highlight the importance of considering genetic variation in baseline dopamine levels in addition to sex, when considering the impact of dopamine on cognition in healthy populations. These findings also have important implications for the many neuropsychiatric disorders that implicate dopamine, cognitive changes and sex differences. Copyright © 2014 Elsevier B.V. All rights reserved.
[Transsexualism: a Brain Disorder that Begins to Known].
López Moratalla, Natalia; Calleja Canela, Amparo
2016-01-01
Transsexualism describes the condition when a person's psychological gender differs from his or her biological sex. People with gender identity disorder suffer persistently from this incongruence and they search hormonal and surgical sex reassignment to the desired anatomical sex. This review, from an ethical perspective, intends to give an overview of structural and functional neurobiological correlations of transsexualism and their course under cross-sex hormonal administration. Several studies demonstrate an increased functional connectivity between cortex regions reaffirming psychosocial distress of psychologicalbiological sex incongruity. Such distress can be ascribed to a disharmonic body image due to changes in the functional connectivity of the key components of body representation network. These brain alterations seem to imply a strategic mechanism dissociating bodily emotions from bodily images. For a number of sexually dimorphic brain structures or processes, signs of feminization or masculinization are observable in transsexual individuals, who during hormonal administration seem to partly further adjust to characteristics of the desired sex. These changes allow a reduction of psychosocial distress. However, a model leading to a ″gender affirmation″ does not solve the problem, since brain disorders causing it are not corrected. This is a serious medical ethics issue. Prejudices should be left aside. To know what happens in the brain of transsexuals is a medical need, both to define what is and what is not, and so to choose an adequate treatment, and to decide and guide legal actions.
Muscularity as a function of species, sex and age in small mammals
NASA Technical Reports Server (NTRS)
Pace, N.; Rahlmann, D. F.; Smith, A. H.
1984-01-01
Changes in the body skeletal muscle mass SMM (measured as a function of the ratio between the body creatine mass and the fat-free muscle creatine), and in muscularity (expressed as the ratio of SMM to fat-free body mass) were studied as functions of age, sex, and species in mouse, rat, hamster, guinea pig, and rabbit. Six animals of each sex were examined in eight age cohorts ranging from 1 to 24 months. Both species and age factors affect SMM. Strong sexual dimorphism in the SMM changes with age was displayed by mouse, rat, and guinea pig, whereas the hamster and rabbit were statistically monomorphic. The mouse, rat, and hamster attain a maximal SMM at about 1 year of age, whereas in the guinea pig and rabbit the decrease in SMM starts after 2 years. The value of muscularity reached a peak at age of 2-3 months in all animals of both sexes, with a pronounced difference among the species. The mouse emerged as the most muscular, while the guinea pig the least muscular, of all species.
Tylee, Daniel S; Espinoza, Alfred J; Hess, Jonathan L; Tahir, Muhammad A; McCoy, Sarah Y; Rim, Joshua K; Dhimal, Totadri; Cohen, Ori S; Glatt, Stephen J
2017-03-01
Genome-wide expression studies of samples derived from individuals with autism spectrum disorder (ASD) and their unaffected siblings have been widely used to shed light on transcriptomic differences associated with this condition. Females have historically been under-represented in ASD genomic studies. Emerging evidence from studies of structural genetic variants and peripheral biomarkers suggest that sex-differences may exist in the biological correlates of ASD. Relatively few studies have explicitly examined whether sex-differences exist in the transcriptomic signature of ASD. The present study quantified genome-wide expression values by performing RNA sequencing on transformed lymphoblastoid cell lines and identified transcripts differentially expressed between same-sex, proximal-aged sibling pairs. We found that performing separate analyses for each sex improved our ability to detect ASD-related transcriptomic differences; we observed a larger number of dysregulated genes within our smaller set of female samples (n = 12 sibling pairs), as compared with the set of male samples (n = 24 sibling pairs), with small, but statistically significant overlap between the sexes. Permutation-based gene-set analyses and weighted gene co-expression network analyses also supported the idea that the transcriptomic signature of ASD may differ between males and females. We discuss our findings in the context of the relevant literature, underscoring the need for future ASD studies to explicitly account for differences between the sexes. Autism Res 2017, 10: 439-455. © 2016 International Society for Autism Research, Wiley Periodicals, Inc. © 2016 International Society for Autism Research, Wiley Periodicals, Inc.
Men appear more lateralized when noticing emotion in male faces.
Rahman, Qazi; Anchassi, Tarek
2012-02-01
Empirical tests of the "right hemisphere dominance" versus "valence" theories of emotion processing are confounded by known sex differences in lateralization. Moreover, information about the sex of the person posing an emotion might be processed differently by men and women because of an adaptive male bias to notice expressions of threat and vigilance in other male faces. The purpose of this study was to investigate whether sex of poser and emotion displayed influenced lateralization in men and women by analyzing "laterality quotient" scores on a test which depicts vertically split chimeric faces, formed with one half showing a neutral expression and the other half showing an emotional expression. We found that men (N = 50) were significantly more lateralized for emotions indicative of vigilance and threat (happy, sad, angry, and surprised) in male faces relative to female faces and compared to women (N = 44). These data indicate that sex differences in functional cerebral lateralization for facial emotion may be specific to the emotion presented and the sex of face presenting it. PsycINFO Database Record (c) 2012 APA, all rights reserved
Lateralization for Processing Facial Emotions in Gay Men, Heterosexual Men, and Heterosexual Women.
Rahman, Qazi; Yusuf, Sifat
2015-07-01
This study tested whether male sexual orientation and gender nonconformity influenced functional cerebral lateralization for the processing of facial emotions. We also tested for the effects of sex of poser and emotion displayed on putative differences. Thirty heterosexual men, 30 heterosexual women, and 40 gay men completed measures of demographic variables, recalled childhood gender nonconformity (CGN), IQ, and the Chimeric Faces Test (CFT). The CFT depicts vertically split chimeric faces, formed with one half showing a neutral expression and the other half showing an emotional expression and performance is measured using a "laterality quotient" (LQ) score. We found that heterosexual men were significantly more right-lateralized when viewing female faces compared to heterosexual women and gay men, who did not differ significantly from each other. Heterosexual women and gay men were more left-lateralized for processing female faces. There were no significant group differences in lateralization for male faces. These results remained when controlling for age and IQ scores. There was no significant effect of CGN on LQ scores. These data suggest that gay men are feminized in some aspects of functional cerebral lateralization for facial emotion. The results were discussed in relation to the selectivity of functional lateralization and putative brain mechanisms underlying sexual attraction towards opposite-sex and same-sex targets.
The effect of sex on the repeatability of evolution in different environments.
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.
Clinical epidemiology of Alzheimer's disease: assessing sex and gender differences.
Mielke, Michelle M; Vemuri, Prashanthi; Rocca, Walter A
2014-01-01
With the aging of the population, the burden of Alzheimer's disease (AD) is rapidly expanding. More than 5 million people in the US alone are affected with AD and this number is expected to triple by 2050. While men may have a higher risk of mild cognitive impairment (MCI), an intermediate stage between normal aging and dementia, women are disproportionally affected with AD. One explanation is that men may die of competing causes of death earlier in life, so that only the most resilient men may survive to older ages. However, many other factors should also be considered to explain the sex differences. In this review, we discuss the differences observed in men versus women in the incidence and prevalence of MCI and AD, in the structure and function of the brain, and in the sex-specific and gender-specific risk and protective factors for AD. In medical research, sex refers to biological differences such as chromosomal differences (eg, XX versus XY chromosomes), gonadal differences, or hormonal differences. In contrast, gender refers to psychosocial and cultural differences between men and women (eg, access to education and occupation). Both factors play an important role in the development and progression of diseases, including AD. Understanding both sex- and gender-specific risk and protective factors for AD is critical for developing individualized interventions for the prevention and treatment of AD.
Clinical epidemiology of Alzheimer’s disease: assessing sex and gender differences
Mielke, Michelle M; Vemuri, Prashanthi; Rocca, Walter A
2014-01-01
With the aging of the population, the burden of Alzheimer’s disease (AD) is rapidly expanding. More than 5 million people in the US alone are affected with AD and this number is expected to triple by 2050. While men may have a higher risk of mild cognitive impairment (MCI), an intermediate stage between normal aging and dementia, women are disproportionally affected with AD. One explanation is that men may die of competing causes of death earlier in life, so that only the most resilient men may survive to older ages. However, many other factors should also be considered to explain the sex differences. In this review, we discuss the differences observed in men versus women in the incidence and prevalence of MCI and AD, in the structure and function of the brain, and in the sex-specific and gender-specific risk and protective factors for AD. In medical research, sex refers to biological differences such as chromosomal differences (eg, XX versus XY chromosomes), gonadal differences, or hormonal differences. In contrast, gender refers to psychosocial and cultural differences between men and women (eg, access to education and occupation). Both factors play an important role in the development and progression of diseases, including AD. Understanding both sex- and gender-specific risk and protective factors for AD is critical for developing individualized interventions for the prevention and treatment of AD. PMID:24470773
ERIC Educational Resources Information Center
Huxley, Virginia H.
2007-01-01
The ability to recognize and appreciate from a reproductive standpoint that males and females possess different attributes has been long standing. Only more recently have we begun to look more deeply into both the similarities and differences between men and women, as well as between boys and girls, with respect to the structure and function of…
Predictors of how often and when people fall in love.
Galperin, Andrew; Haselton, Martie
2010-01-19
A leading theory of romantic love is that it functions to make one feel committed to one's beloved, as well as to signal this commitment to the beloved (Frank, 1988). Because women tend to be skeptical of men's commitment, this view entails that men may have evolved to fall in love first, in order to show their commitment to women. Using a sample of online participants of a broad range of ages, this study tested this sex difference and several related individual difference hypotheses concerning the ease of falling in love. There was mixed evidence for sex differences: only some measures indicated that men are generally more love-prone than are women. We also found that men were more prone to falling in love if they tended to overestimate women's sexual interest and highly valued physical attractiveness in potential partners. Women were more prone to falling in love if they had a stronger sex drive. These results provide modest support for the existence of sex differences in falling in love, as well as initial evidence for links between several individual difference variables and the propensity to fall in love.
Kim, Ji Eun; Song, In Han; Lee, Sang-Hyuk
2017-09-01
Although affective disorders have been known to have sex differences in the associated clinical characteristics and quality of life (QOL), sex differences among patients with panic disorder (PD) have remained relatively unexplored in Korea. We examined the sex differences in different types of stressful life events (SLEs), coping styles, symptom severity, and health-related QOL (HRQOL) in patients with PD. Data from 291 female and 254 male participants diagnosed with PD were analyzed using a structured clinical interview following the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition criteria. Females with PD reported more SLEs including separation issues, physical illness or disability, and pregnancy-related problems than males. They also reported lower levels of confrontation and help-seeking coping strategies and higher levels of agoraphobia in symptom severity than males. The HRQOL of females with PD was significantly lower than male in physical functioning of HRQOL. This study suggests that the patient's sex is relevant to the assessment and treatment of PD.
Bašić, Željana; Anterić, Ivana; Vilović, Katarina; Petaros, Anja; Bosnar, Alan; Madžar, Tomislav; Polašek, Ozren; Anđelinović, Šimun
2013-01-01
Aim To investigate the usefulness of humerus measurement for sex determination in a sample of medieval skeletons from the Eastern Adriatic Coast. Additional aim was to compare the results with contemporary female population. Methods Five humerus measurements (maximum length, epicondylar width, maximum vertical diameter of the head, maximum and minimum diameter of the humerus at midshaft) for 80 male and 35 female medieval and 19 female contemporary humeri were recorded. Only sufficiently preserved skeletons and those with no obvious pathological or traumatic changes that could affect the measurements were included. For ten samples, analysis of DNA was performed in order to determine sex using amelogenin. Results The initial comparison of men and women indicated significant differences in all five measures (P < 0.001). Discriminant function for sex determination indicated that as much as 85% of cases could be properly categorized, with better results in men (86%) than women (80%). Furthermore, the comparison of the medieval and contemporary women did not show significant difference in any of the measured features. Sex results obtained by anthropological and DNA analysis matched in all 10 cases. Conclusion The results indicate that humerus measurement in Croatian medieval population may be sufficient to determine the sex of the skeleton. Furthermore, it seems that secular changes have not substantially affected contemporary population, suggesting that the results of this study are transferable to contemporary population as well. PMID:23771758
Shepard, Ryan; Page, Chloe E; Coutellier, Laurence
2016-09-22
Stress-induced modifications of the prefrontal cortex (PFC) are believed to contribute to the onset of mood disorders, such as depression and anxiety, which are more prevalent in women. In depression, the PFC is hypoactive; however the origin of this hypoactivity remains unclear. Possibly, stress could impact the prefrontal GABAergic inhibitory system that, as a result, impairs the functioning of downstream limbic structures controlling emotions. Preclinical evidence indicates that the female PFC is more sensitive to the effects of stress. These findings suggest that exposure to stress could lead to sex-specific alterations in prefrontal GABAergic signaling, which contribute to sex-specific abnormal functioning of limbic regions. These limbic changes could promote the onset of depressive and anxiety behaviors in a sex-specific manner, providing a possible mechanism mediating sex differences in the clinical presentation of stress-related mood disorders. We addressed this hypothesis using a mouse model of stress-induced depressive-like behaviors: the unpredictable chronic mild stress (UCMS) paradigm. We observed changes in prefrontal GABAergic signaling after exposure to UCMS most predominantly in females. Increased parvalbumin (PV) expression and decreased prefrontal neuronal activity were correlated in females with severe emotionality deficit following UCMS, and with altered activity of the amygdala. In males, small changes in emotionality following UCMS were associated with minor changes in prefrontal PV expression, and with hypoactivity of the nucleus accumbens. Our data suggest that prefrontal hypoactivity observed in stress-related mood disorders could result from stress-induced increases in PV expression, particularly in females. This increased vulnerability of the female prefrontal PV system to stress could underlie sex differences in the prevalence and symptomatology of stress-related mood disorders. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.
Beal, Andria P; Martin, F Douglas; Hale, Matthew C
2018-02-01
Sex-bias in gene expression is a widespread mechanism for controlling the development of phenotypes that differ between males and females. Most studies on sex-bias in gene expression have focused on species that exhibit traditional sex-roles (male-male competition and female parental care). By contrast the Syngnathid fishes (sea horses, pipefish, and sea dragons) are a group of organisms where many species exhibit male brooding and sex-role reversal (female-female competition for mates and paternal parental care), and little is known about how patterns of sex-bias in gene expression vary in species with sex-role reversal. Here we utilize RNA-seq technology to investigate patterns of sex-bias in gene expression in the brain tissue of the Gulf Pipefish (Syngnathus scovelli) a species that exhibits sex-role reversal. Gene expression analysis identified 73 sex-biased genes, 26 genes upregulated in females and 47 genes upregulated in males. Gene ontology analysis found 52 terms enriched for the sex-biased genes in a wide range of pathways suggesting that multiple functions and processes differ between the sexes. We focused on two areas of interest: sex steroids/hormones and circadian rhythms, both of which exhibited sex-bias in gene expression, and are known to influence sexual development in other species. Lastly, the work presented herein contributes to a growing body of genome data available for the Syngnathids, increasing our knowledge on patterns of gene expression in these unusual fishes. Copyright © 2017 Elsevier B.V. All rights reserved.
Sex differences in succumbing to sexual temptations: a function of impulse or control?
Tidwell, Natasha D; Eastwick, Paul W
2013-12-01
Men succumb to sexual temptations (e.g., infidelity, mate poaching) more than women. Explanations for this effect vary; some researchers propose that men and women differ in sexual impulse strength, whereas others posit a difference in sexual self-control. These studies are the first to test such underlying mechanisms. In Study 1, participants reported on their impulses and intentional control exertion when they encountered a real-life tempting but forbidden potential partner. Study 2 required participants to perform a reaction-time task in which they accepted/rejected potential partners, and we used process dissociation to separate the effects of impulse and control. In both studies, men succumbed to the sexual temptations more than women, and this sex difference emerged because men experienced stronger impulses, not because they exerted less intentional control. Implications for the integration of evolutionary and self-regulatory perspectives on sex differences are discussed.
Structural and functional correlates of epileptogenesis — Does gender matter?
Savic, Ivanka; Engel, Jerome
2016-01-01
In the majority of neuropsychiatric conditions, marked gender-based differences have been found in the epidemiology, clinical manifestations, and therapy of disease. One possible reason is that sex differences in cerebral morphology, structural and functional connections, render men and women differentially vulnerable to various disease processes. The present review addresses this issue with respect to the functional and structural correlates to some forms of epilepsy. PMID:24943053
ERIC Educational Resources Information Center
Castillo, Yenys; Muscarella, Frank; Szuchman, Lenore T.
2011-01-01
This study examined college students' perceptions of same-sex harassment as a function of the observer's gender, the initiator's physical attractiveness, and observers' attitudes toward lesbians and gay men. Ninety-six college students read a scenario portraying a professor's sexual advances toward a student. The Perception of Harassment…
Gramaglia, Carla; Bert, Fabrizio; Lombardi, Ada; Feggi, Alessandro; Porro, Marica; Siliquini, Roberta; Gualano, Maria Rosaria; Torre, Eugenio; Zeppegno, Patrizia
2014-01-01
We assessed sex differences in a sample of first-admission psychiatric inpatients with and without comorbid substance use disorder (SUD) to identify possible risk factors and targets for sex-tailored treatment interventions. A retrospective study of first admissions to the University Psychiatry Ward, "Maggiore della Carità" Hospital, Novara, Italy, between 2003 and 2012 was accomplished. The clinical charts of patients with (N = 362) and without comorbid SUD (N = 1111) were reviewed. Differences in employment, educational, and marital statuses were found between male and female psychiatric patients with and without comorbid SUD. Having a degree was a protective factor for males, whereas it was a risk factor for females. Being divorced and having family problems were both risk factors for comorbidity in females. Regarding the diagnosis, results overlapped in males and females, and both affective and other disorders were risk factors for a comorbid SUD. A significant difference between male and female psychiatric patients with a comorbid SUD was the males' overall poorer psychosocial functioning. Marital status and family problems were risk factors for comorbid SUD in females. Both males and females showed various pathways of access to and choices of substances and, eventually, experienced different impacts on their lives. Hospitalization might help to set up a targeted intervention for patients with comorbidity, while accounting for sex differences. With respect to males, a treatment approach focused on the substance alone might help improve their functioning; females might have a greater benefit from a treatment approach focused on distress, family problems, and relational issues.
Sex, Glia, and Development: interactions in health and disease
Schwarz, Jaclyn M.; Bilbo, Staci D.
2012-01-01
Microglia and astrocytes are the primary immune cells within the central nervous system. Microglia influence processes including neural development, synaptic plasticity and cognition; while their activation and production of immune molecules can induce stereotyped sickness behaviors or pathologies including cognitive dysfunction. Given their role in health and disease, we propose that glia may be also be a critical link in understanding the etiology of many neuropsychiatric disorders that present with a strong sex-bias in their symptoms or prevalence. Specifically, males are more likely to be diagnosed with disorders that have distinct developmental origins such as autism or schizophrenia. In contrast, females are more likely to be diagnosed with disorders that present later in life, after the onset of adolescence, such as depression and anxiety disorders. In this review we will summarize the evidence suggesting that sex differences in the colonization and function of glia within the normal developing brain may contribute to distinct windows of vulnerability between males and females. We will also highlight the current gaps in our knowledge as well as the future directions and considerations of research aimed at understanding the link between neuroimmune function and sex differences in mental health disorders. PMID:22387107
Shi, Yu; Liu, Wenguang; He, Maoxian
2018-04-01
Bivalve mollusks exhibit hermaphroditism and sex reversal/differentiation. Studies generally focus on transcriptional profiling and specific genes related to sex determination and differentiation. Few studies on sex reversal/differentiation have been reported. A combination analysis of gonad proteomics and transcriptomics was conducted on Chlamys nobilis to provide a systematic understanding of sex reversal/differentiation in bivalves. We obtained 4258 unique peptides and 93,731 unigenes with good correlation between messenger RNA and protein levels. Candidate genes in sex reversal/differentiation were found: 15 genes differentially expressed between sexes were identified and 12 had obvious sexual functions. Three novel genes (foxl2, β-catenin, and sry) were expressed highly in intersex individuals and were likely involved in the control of gonadal sex in C. nobilis. High expression of foxl2 or β-catenin may inhibit sry and activate 5-HT receptor and vitellogenin to maintain female development. High expression of sry may inhibit foxl2 and β-catenin and activate dmrt2, fem-1, sfp2, sa6, Amy-1, APCP4, and PLK to maintain male function. High expression of sry, foxl2, and β-catenin in C. nobilis may be involved in promoting and maintaining sex reversal/differentiation. The downstream regulator may not be dimorphic expressed genes, but genes expressed in intersex individuals, males and females. Different expression patterns of sex-related genes and gonadal histological characteristics suggested that C. nobilis may change its sex from male to female. These findings suggest highly conserved sex reversal/differentiation with diverged regulatory pathways during C. nobilis evolution. This study provides valuable genetic resources for understanding sex reversal/differentiation (intersex) mechanisms and pathways underlying bivalve reproductive regulation.
van Tetering, Marleen A J; Jolles, Jelle
2017-01-01
Executive functions (EFs) develop over the period of early childhood and adolescence up until young adulthood. Individual children differ substantially in the pace at which their EFs develop, and characteristics such as sex and the level of parental education (LPE) are thought to contribute to these differences. In the present study, we assessed age-related changes in EFs as perceived and evaluated by teachers and parents as well as the influence of sex and LPE on their evaluations. We used a newly developed observer-report questionnaire, the Amsterdam Executive Function Inventory (AEFI). The AEFI assesses three important components of the executive aspects of daily life behavior in 13 questions: Attention; Self-control and Self-monitoring; and Planning and Initiative taking. Teachers and parents evaluated these aspects of executive functioning in 186 schoolchildren in grades 3-6 (age: 9-12 years). Age effects within grades and differences in social economic status between the four participating schools were controlled. Results showed a significant increase in teacher-perceived EFs from third to fourth grades and from fifth to sixth grades. This development was influenced both by the sex of the child and by the LPE. As perceived by teachers, the component self-control and self-monitoring was higher for girls than for boys, and planning abilities were higher for children from families with a higher LPE. Additional analyses showed that there is a systematic and statistically significant difference between the evaluations of the teachers and that of parents. Parents reported higher scores for planning, whereas teachers reported higher scores for self-control and self-monitoring. Evaluations by parents and teachers were different for girls, but not for boys. These findings are important because they imply that the development of EFs as perceived by parents and teachers is influenced by child-related factors. Second, there are clear differences in evaluations between teachers and parents. The AEFI appears to be a tool that is easily used by parents and teachers and shows potential for monitoring the development of EFs as perceived by significant others during young adolescence.
LeBoeuf, Brigitte; Garcia, L. Rene
2016-01-01
Sexual dimorphism can be achieved using a variety of mechanisms, including sex-specific circuits and sex-specific function of shared circuits, though how these work together to produce sexually dimorphic behaviors requires further investigation. Here, we explore how components of the sex-shared defecation circuitry are incorporated into the sex-specific male mating circuitry in Caenorhabditis elegans to produce successful copulation. Using behavioral studies, calcium imaging, and genetic manipulation, we show that aspects of the defecation system are coopted by the male copulatory circuitry to facilitate intromission and ejaculation. Similar to hermaphrodites, male defecation is initiated by an intestinal calcium wave, but circuit activity is coordinated differently during mating. In hermaphrodites, the tail neuron DVB promotes expulsion of gut contents through the release of the neurotransmitter GABA onto the anal depressor muscle. However, in the male, both neuron and muscle take on modified functions to promote successful copulation. Males require calcium-dependent activator protein for secretion (CAPS)/unc-31, a dense core vesicle exocytosis activator protein, in the DVB to regulate copulatory spicule insertion, while the anal depressor is remodeled to promote release of sperm into the hermaphrodite. This work shows how sex-shared circuitry is modified in multiple ways to contribute to sex-specific mating. PMID:28031243
Extraordinary Sex Ratios: Cultural Effects on Ecological Consequences
Molnár, Ferenc; Caraco, Thomas; Korniss, Gyorgy
2012-01-01
We model sex-structured population dynamics to analyze pairwise competition between groups differing both genetically and culturally. A sex-ratio allele is expressed in the heterogametic sex only, so that assumptions of Fisher’s analysis do not apply. Sex-ratio evolution drives cultural evolution of a group-associated trait governing mortality in the homogametic sex. The two-sex dynamics under resource limitation induces a strong Allee effect that depends on both sex ratio and cultural trait values. We describe the resulting threshold, separating extinction from positive growth, as a function of female and male densities. When initial conditions avoid extinction due to the Allee effect, different sex ratios cannot coexist; in our model, greater female allocation always invades and excludes a lesser allocation. But the culturally transmitted trait interacts with the sex ratio to determine the ecological consequences of successful invasion. The invading female allocation may permit population persistence at self-regulated equilibrium. For this case, the resident culture may be excluded, or may coexist with the invader culture. That is, a single sex-ratio allele in females and a cultural dimorphism in male mortality can persist; a low-mortality resident trait is maintained by father-to-son cultural transmission. Otherwise, the successfully invading female allocation excludes the resident allele and culture and then drives the population to extinction via a shortage of males. Finally, we show that the results obtained under homogeneous mixing hold, with caveats, in a spatially explicit model with local mating and diffusive dispersal in both sexes. PMID:22952669
Extraordinary sex ratios: cultural effects on ecological consequences.
Molnár, Ferenc; Caraco, Thomas; Korniss, Gyorgy
2012-01-01
We model sex-structured population dynamics to analyze pairwise competition between groups differing both genetically and culturally. A sex-ratio allele is expressed in the heterogametic sex only, so that assumptions of Fisher's analysis do not apply. Sex-ratio evolution drives cultural evolution of a group-associated trait governing mortality in the homogametic sex. The two-sex dynamics under resource limitation induces a strong Allee effect that depends on both sex ratio and cultural trait values. We describe the resulting threshold, separating extinction from positive growth, as a function of female and male densities. When initial conditions avoid extinction due to the Allee effect, different sex ratios cannot coexist; in our model, greater female allocation always invades and excludes a lesser allocation. But the culturally transmitted trait interacts with the sex ratio to determine the ecological consequences of successful invasion. The invading female allocation may permit population persistence at self-regulated equilibrium. For this case, the resident culture may be excluded, or may coexist with the invader culture. That is, a single sex-ratio allele in females and a cultural dimorphism in male mortality can persist; a low-mortality resident trait is maintained by father-to-son cultural transmission. Otherwise, the successfully invading female allocation excludes the resident allele and culture and then drives the population to extinction via a shortage of males. Finally, we show that the results obtained under homogeneous mixing hold, with caveats, in a spatially explicit model with local mating and diffusive dispersal in both sexes.
Functional fitness norms for community-dwelling older adults in Hong Kong.
Chung, Pak-Kwong; Zhao, Yanan; Liu, Jing-Dong; Quach, Binh
2016-01-01
This study aimed to establish normative data for older adults in Hong Kong and explore age and sex differences in functional fitness. A sample of 944 independent community-dwellers, aged 65-74 years, was evaluated using the Senior Fitness Test battery in addition to hand grip and single leg stance tests. Normative data were reported for the 10th, 25th, 50th, 75th, and 90th percentiles in 5-year age groups. Except for upper extremity muscle strength in women and body mass index (BMI) in both sexes, ageing-associated degradation was observed in all testing parameters especially in flexibility, balance, and agility. Significant sex differences were found in all testing parameters with the exception of BMI and static balance with eyes open. Moreover, men demonstrated higher capacities for muscle strength, agility, balance, and aerobic endurance, whereas women showed superior flexibility. The normative values enable the evaluation of individual performance regarding the fitness status of older adults in Hong Kong. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Crane, Natania A.; Schuster, Randi Melissa; Fusar-Poli, Paolo; Gonzalez, Raul
2012-01-01
Decades of research have examined the effects of cannabis on neurocognition. Recent advances in this field provide us with a better understanding of how cannabis use influences neurocognition both acutely (during intoxication) and non-acutely (after acute effects subside). Evidence of problems with episodic memory is one of the most consistent findings reported; however, several other neurocognitive domains appear to be adversely affected by cannabis use under various conditions. There is significant variability in findings across studies, thus a discussion of potential moderators is increasingly relevant. The purpose of this review was to 1) provide an update on research of cannabis’ acute and non-acute effects on neurocognition, with a focus on findings since 2007 and 2) suggest and discuss how neurodevelopmental issues and sex differences may influence cannabis effects on neurocognition. Finally we discuss how future investigations may lead to better understanding of the complex interplay among cannabis, stages of neurodevelopment, and sex on neurocognitive functioning. PMID:23129391
SHBG and endothelial function in older subjects.
Maggio, Marcello; Cattabiani, Chiara; Lauretani, Fulvio; Mantovani, Marco; Buttò, Valeria; De Vita, Francesca; Volpi, Riccardo; Artoni, Andrea; Giallauria, Francesco; Zuliani, Giovanni; Aloe, Rosalia; Lippi, Giuseppe; Ceresini, Graziano; Cederholm, Tommy; Ceda, Gian Paolo; Lind, Lars
2013-10-03
Endothelial dysfunction is predictor of cardiovascular diseases that have different prevalence in men and women before menopause. Sex hormones and sex hormone binding globulin (SHBG), novel risk factors for diabetes and cardiovascular diseases even in older individuals, might explain this difference. However, the relationship between these hormones and endothelial function has never been addressed in the elderly. 430 men and,424 women 70 years older of Prospective Study of the Vasculature in Uppsala Seniors study, with complete data on SHBG, testosterone(T), estradiol(E2), endothelium-independent vasodilation (EIDV), endothelium-dependent vasodilation(EDV), flow-mediated vasodilation (FMD) and the pulse wave analysis (reflection index, RI) were evaluated. Multivariate regression analysis adjusted for confounders was used to assess the relationship between T, E2, SHBG and endothelial function. In men we found a positive relationship between SHBG and EDV (β ± SE 3.60 ± 0.83, p<0.0001), EIDV (2.42 ± 0.58, p<0.0001) but not with FMD. The relationship between SHBG and EDV and EIDV was maintained after adjustment for sex (1.64 ± 0.47, p<0.001 and 1.79 ± 0.35, p<0.0006, respectively). After adjustment for confounders, the relationship between SHBG and EDV and EIDV was still statistically significant (2.63 ± 0.90 and 1.86 ± 0.63, p = 0.004 for both). In women SHBG and EIDV were positively associated (1.58 ± 0.46; p = 0.0007), and this relationship was independent of sex (1.79 ± 0.35; p<0.001). No significant interaction SHBG * SEX was found for EIDV (p = 0.72). In a combined analysis in two sexes, SHBG and EIDV were positively associated (1.13 ± 0.45; p = 0.01). SHBG was not associated with EDV, FMD and RI. No significant relationship was found between T or E2 and EDV, EIDV, FMD or RI in both sexes. In older men SHBG, but not T and E2, is positively and independently associated with EDV in resistance arteries. In both sexes, SHBG was positively and independently associated with EIDV. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.
Uretsky, Elanah
2014-01-01
Mention of the term sex work often invokes images of marginalized women at risk for HIV infection. Such images, however, are counterintuitive to the functional role intended by the movement that spawned use of the terms `sex work' and `sex worker'. This article looks at the sexual practices of men in urban China to argue for a return to a functional definition of `sex work', which was originally meant to legitimize the role sex plays in work. The progenitors of this movement intended to use `sex work' as a means to legitimize sex as an income generating activity for women involved in prostitution. I show that sex can also serve a functional role in the work-related duties of men seeking economic and political success in contemporary urban China. Men in China utilize sex as one way for demonstrating the loyalty necessary to access state-owned and controlled resources in a market economy governed under a Leninist system. Overall the article demonstrates that reclaiming perception of sex work as a functional rather than behavioral category can expand its use for preventing HIV among the broad subset of people who engage in sex as part of their work. PMID:25642103
Uretsky, Elanah
2015-01-01
Mention of the term sex work often invokes images of marginalized women at risk for HIV infection. Such images, however, are counterintuitive to the functional role intended by the movement that spawned use of the terms `sex work' and `sex worker'. This article looks at the sexual practices of men in urban China to argue for a return to a functional definition of `sex work', which was originally meant to legitimize the role sex plays in work. The progenitors of this movement intended to use `sex work' as a means to legitimize sex as an income generating activity for women involved in prostitution. I show that sex can also serve a functional role in the work-related duties of men seeking economic and political success in contemporary urban China. Men in China utilize sex as one way for demonstrating the loyalty necessary to access state-owned and controlled resources in a market economy governed under a Leninist system. Overall the article demonstrates that reclaiming perception of sex work as a functional rather than behavioral category can expand its use for preventing HIV among the broad subset of people who engage in sex as part of their work.
Connallon, Tim; Clark, Andrew G
2010-12-01
Sex-biased genes--genes that are differentially expressed within males and females--are nonrandomly distributed across animal genomes, with sex chromosomes and autosomes often carrying markedly different concentrations of male- and female-biased genes. These linkage patterns are often gene- and lineage-dependent, differing between functional genetic categories and between species. Although sex-specific selection is often hypothesized to shape the evolution of sex-linked and autosomal gene content, population genetics theory has yet to account for many of the gene- and lineage-specific idiosyncrasies emerging from the empirical literature. With the goal of improving the connection between evolutionary theory and a rapidly growing body of genome-wide empirical studies, we extend previous population genetics theory of sex-specific selection by developing and analyzing a biologically informed model that incorporates sex linkage, pleiotropy, recombination, and epistasis, factors that are likely to vary between genes and between species. Our results demonstrate that sex-specific selection and sex-specific recombination rates can generate, and are compatible with, the gene- and species-specific linkage patterns reported in the genomics literature. The theory suggests that sexual selection may strongly influence the architectures of animal genomes, as well as the chromosomal distribution of fixed substitutions underlying sexually dimorphic traits. © 2010 The Author(s). Evolution© 2010 The Society for the Study of Evolution.
Smith, David V; Utevsky, Amanda V; Bland, Amy R; Clement, Nathan; Clithero, John A; Harsch, Anne E W; McKell Carter, R; Huettel, Scott A
2014-07-15
A central challenge for neuroscience lies in relating inter-individual variability to the functional properties of specific brain regions. Yet, considerable variability exists in the connectivity patterns between different brain areas, potentially producing reliable group differences. Using sex differences as a motivating example, we examined two separate resting-state datasets comprising a total of 188 human participants. Both datasets were decomposed into resting-state networks (RSNs) using a probabilistic spatial independent component analysis (ICA). We estimated voxel-wise functional connectivity with these networks using a dual-regression analysis, which characterizes the participant-level spatiotemporal dynamics of each network while controlling for (via multiple regression) the influence of other networks and sources of variability. We found that males and females exhibit distinct patterns of connectivity with multiple RSNs, including both visual and auditory networks and the right frontal-parietal network. These results replicated across both datasets and were not explained by differences in head motion, data quality, brain volume, cortisol levels, or testosterone levels. Importantly, we also demonstrate that dual-regression functional connectivity is better at detecting inter-individual variability than traditional seed-based functional connectivity approaches. Our findings characterize robust-yet frequently ignored-neural differences between males and females, pointing to the necessity of controlling for sex in neuroscience studies of individual differences. Moreover, our results highlight the importance of employing network-based models to study variability in functional connectivity. Copyright © 2014 Elsevier Inc. All rights reserved.
Sex Differences and Autism: Brain Function during Verbal Fluency and Mental Rotation
Minati, Ludovico; Baron-Cohen, Simon; Lombardo, Michael V.; Lai, Meng-Chuan; Walker, Anne; Howard, Dawn; Gray, Marcus A.; Harrison, Neil A.; Critchley, Hugo D.
2012-01-01
Autism spectrum conditions (ASC) affect more males than females. This suggests that the neurobiology of autism: 1) may overlap with mechanisms underlying typical sex-differentiation or 2) alternately reflect sex-specificity in how autism is expressed in males and females. Here we used functional magnetic resonance imaging (fMRI) to test these alternate hypotheses. Fifteen men and fourteen women with Asperger syndrome (AS), and sixteen typically developing men and sixteen typically developing women underwent fMRI during performance of mental rotation and verbal fluency tasks. All groups performed the tasks equally well. On the verbal fluency task, despite equivalent task-performance, both males and females with AS showed enhanced activation of left occipitoparietal and inferior prefrontal activity compared to controls. During mental rotation, there was a significant diagnosis-by-sex interaction across occipital, temporal, parietal, middle frontal regions, with greater activation in AS males and typical females compared to AS females and typical males. These findings suggest a complex relationship between autism and sex that is differentially expressed in verbal and visuospatial domains. PMID:22701630
Sex differences and autism: brain function during verbal fluency and mental rotation.
Beacher, Felix D C C; Radulescu, Eugenia; Minati, Ludovico; Baron-Cohen, Simon; Lombardo, Michael V; Lai, Meng-Chuan; Walker, Anne; Howard, Dawn; Gray, Marcus A; Harrison, Neil A; Critchley, Hugo D
2012-01-01
Autism spectrum conditions (ASC) affect more males than females. This suggests that the neurobiology of autism: 1) may overlap with mechanisms underlying typical sex-differentiation or 2) alternately reflect sex-specificity in how autism is expressed in males and females. Here we used functional magnetic resonance imaging (fMRI) to test these alternate hypotheses. Fifteen men and fourteen women with Asperger syndrome (AS), and sixteen typically developing men and sixteen typically developing women underwent fMRI during performance of mental rotation and verbal fluency tasks. All groups performed the tasks equally well. On the verbal fluency task, despite equivalent task-performance, both males and females with AS showed enhanced activation of left occipitoparietal and inferior prefrontal activity compared to controls. During mental rotation, there was a significant diagnosis-by-sex interaction across occipital, temporal, parietal, middle frontal regions, with greater activation in AS males and typical females compared to AS females and typical males. These findings suggest a complex relationship between autism and sex that is differentially expressed in verbal and visuospatial domains.
Shehri, Fahad Al; Soliman, Khaled E A
2015-08-01
Diagnosis of sex from skeleton or individual bone plays an important role in identifying unknown bodies, parts of bodies or skeletal remains for forensic purposes. This study aims to examine the applicability of the measurements taken from the humerus to assess sex, and to contribute to establishing discriminant function equations for Saudi populations for medico legal applications. Archived X-ray radiographs of humerus for 387 patients (216 males & 171 females) who attended the orthopedic clinics at Suleiman Al-Habib Hospital, Qassim region, KSA in the period from January 2011 to December 2013 were reviewed and analyzed. Five dimensions, including maximum length, vertical head diameter, diameter of head+greater tubercle, right-left diameter at midshaft, and epicondylar breadth were taken and subjected to Univariate and multivariate discriminant function analysis. The studied radiographic dimensions of the humerus indicate that there are significant differences (p<0.05) between the males and females measurements while the difference between right and left measurements was not significant. The findings revealed that the proximal part of the humerus has greater diagnostic accuracy than distal and middle parts. Accuracy of correct classification varies between 68.0% (epicondylar breadth) and 90.4% (vertical head diameter) for univariate analyses. When the multivariate analyses were conducted, three functions were produced, with the accuracy of ranging between 88.4% and 94.3%. These findings suggested that the dimensions of the humerus, especially the measurements taken from the proximal parts, could be used successfully for sex diagnosis. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Poley, Jordan D; Sutherland, Ben J G; Jones, Simon R M; Koop, Ben F; Fast, Mark D
2016-07-04
Salmon lice, Lepeophtheirus salmonis (Copepoda: Caligidae), are highly important ectoparasites of farmed and wild salmonids, and cause multi-million dollar losses to the salmon aquaculture industry annually. Salmon lice display extensive sexual dimorphism in ontogeny, morphology, physiology, behavior, and more. Therefore, the identification of transcripts with differential expression between males and females (sex-biased transcripts) may help elucidate the relationship between sexual selection and sexually dimorphic characteristics. Sex-biased transcripts were identified from transcriptome analyses of three L. salmonis populations, including both Atlantic and Pacific subspecies. A total of 35-43 % of all quality-filtered transcripts were sex-biased in L. salmonis, with male-biased transcripts exhibiting higher fold change than female-biased transcripts. For Gene Ontology and functional analyses, a consensus-based approach was used to identify concordantly differentially expressed sex-biased transcripts across the three populations. A total of 127 male-specific transcripts (i.e. those without detectable expression in any female) were identified, and were enriched with reproductive functions (e.g. seminal fluid and male accessory gland proteins). Other sex-biased transcripts involved in morphogenesis, feeding, energy generation, and sensory and immune system development and function were also identified. Interestingly, as observed in model systems, male-biased L. salmonis transcripts were more frequently without annotation compared to female-biased or unbiased transcripts, suggesting higher rates of sequence divergence in male-biased transcripts. Transcriptome differences between male and female L. salmonis described here provide key insights into the molecular mechanisms controlling sexual dimorphism in L. salmonis. This analysis offers targets for parasite control and provides a foundation for further analyses exploring critical topics such as the interaction between sex and drug resistance, sex-specific factors in host-parasite relationships, and reproductive roles within L. salmonis.
Obesity in children with poorly controlled asthma: Sex differences.
Lang, Jason E; Holbrook, Janet T; Wise, Robert A; Dixon, Anne E; Teague, W Gerald; Wei, Christine Y; Irvin, Charles G; Shade, David; Lima, John J
2013-09-01
Obesity increases asthma risk, and may alter asthma severity. In adults, sex appears to modify the effect of obesity on asthma. Among children, the effect of sex on the relationship between obesity and asthma severity remains less clear, particularly when considering race. To determine how obesity affects disease characteristics in a diverse cohort of children with poorly controlled asthma, and if obesity effects are altered by sex. We analyzed 306 children between 6 and 17 years of age with poorly controlled asthma enrolled in a 6-month trial assessing lansoprazole for asthma control. In this secondary analysis, we determined associations between obesity and symptom severity, spirometry, exacerbation risk, airway biomarkers, bronchial reactivity, and airflow perception. We used both a multivariate linear regression and longitudinal mixed-effect model to determine if obesity interacted with sex to affect asthma severity. Regardless of sex, BMI >95th percentile did not affect asthma control, exacerbation risk or airway biomarkers. Sex changed the effect of obesity on lung function (sex × obesity FEV1%, interaction P-value < 0.01, sex × obesity FEV1/FVC, interaction P-value = 0.03). Obese males had significantly worse airflow obstruction compared to non-obese males, while in females there was no obesity effect on airflow obstruction. In females, obesity was associated with significantly greater FEV1 and FVC, and a trend toward reduced airway reactivity. Obesity did not affect asthma control, airway markers or disease stability; however obesity did affect lung function in a sex-dependent manner. In males, obesity associated with reduced FEV1/FVC, and in females, obesity associated with substantially improved lung function. Copyright © 2012 Wiley Periodicals, Inc.
Picard, Marion Anne-Lise; Cosseau, Céline; Mouahid, Gabriel; Duval, David; Grunau, Christoph; Toulza, Ève; Allienne, Jean-François; Boissier, Jérôme
2015-07-01
The Dmrt (Double sex/Male-abnormal-3 Related Transcription factor) genes have been intensively studied because they represent major transcription factors in the pathways governing sex determination and differentiation. These genes have been identified in animal groups ranging from cnidarians to mammals, and some of the genes functionally studied. Here, we propose to analyze (i) the presence/absence of various Dmrt gene groups in the different taxa across the animal kingdom; (ii) the relative expression levels of the Dmrt genes in each sex; (iii) the specific spatial (by organ) and temporal (by developmental stage) variations in gene expression. This review considers non-mammalian animals at all levels of study (i.e. no particular importance is given to animal models), and using all types of sexual strategy (hermaphroditic or gonochoric) and means of sex determination (i.e. genetic or environmental). To conclude this global comparison, we offer an analysis of the DM domains conserved among the different DMRT proteins, and propose a general sex-specific pattern for each member of the Dmrt gene family. Copyright © 2015 Académie des sciences. Published by Elsevier SAS. All rights reserved.
Spolarics, Zoltan; Peña, Geber; Qin, Yong; Donnelly, Robert J; Livingston, David H
2017-01-01
Females have a longer lifespan and better general health than males. Considerable number of studies also demonstrated that, after trauma and sepsis, females present better outcomes as compared to males indicating sex-related differences in the innate immune response. The current notion is that differences in the immuno-modulatory effects of sex hormones are the underlying causative mechanism. However, the field remains controversial and the exclusive role of sex hormones has been challenged. Here, we propose that polymorphic X-linked immune competent genes, which are abundant in the population are important players in sex-based immuno-modulation and play a key role in causing sex-related outcome differences following trauma or sepsis. We describe the differences in X chromosome (ChrX) regulation between males and females and its consequences in the context of common X-linked polymorphisms at the individual as well as population level. We also discuss the potential pathophysiological and immune-modulatory aspects of ChrX cellular mosaicism, which is unique to females and how this may contribute to sex-biased immune-modulation. The potential confounding effects of ChrX skewing of cell progenitors at the bone marrow is also presented together with aspects of acute trauma-induced de novo ChrX skewing at the periphery. In support of the hypothesis, novel observations indicating ChrX skewing in a female trauma cohort as well as case studies depicting the temporal relationship between trauma-induced cellular skewing and the clinical course are also described. Finally, we list and discuss a selected set of polymorphic X-linked genes, which are frequent in the population and have key regulatory or metabolic functions in the innate immune response and, therefore, are primary candidates for mediating sex-biased immune responses. We conclude that sex-related differences in a variety of disease processes including the innate inflammatory response to injury and infection may be related to the abundance of X-linked polymorphic immune-competent genes, differences in ChrX regulation, and inheritance patterns between the sexes and the presence of X-linked cellular mosaicism, which is unique to females.
Interactions between hormones and epilepsy.
Taubøll, Erik; Sveberg, Line; Svalheim, Sigrid
2015-05-01
There is a complex, bidirectional interdependence between sex steroid hormones and epilepsy; hormones affect seizures, while seizures affect hormones thereby disturbing reproductive endocrine function. Both female and male sex steroid hormones influence brain excitability. For the female sex steroid hormones, progesterone and its metabolites are anticonvulsant, while estrogens are mainly proconvulsant. The monthly fluctuations in hormone levels of estrogen and progesterone are the basis for catamenial epilepsy described elsewhere in this issue. Androgens are mainly anticonvulsant, but the effects are more varied, probably because of its metabolism to, among others, estradiol. The mechanisms for the effects of sex steroid hormones on brain excitability are related to both classical, intracellularly mediated effects, and non-classical membrane effects due to binding to membrane receptors. The latter are considered the most important in relation to epilepsy. The different sex steroids can also be further metabolized within the brain to different neurosteroids, which are even more potent with regard to their effect on excitability. Estrogens potentiate glutamate responses, primarily by potentiating NMDA receptor activity, but also by affecting GABA-ergic mechanisms and altering brain morphology by increasing dendritic spine density. Progesterone and its main metabolite 5α-pregnan-3α-ol-20-one (3α-5α-THP) act mainly to enhance postsynaptic GABA-ergic activity, while androgens enhance GABA-activated currents. Seizures and epileptic discharges also affect sex steroid hormones. There are close anatomical connections between the temporolimbic system and the hypothalamus controlling the endocrine system. Several studies have shown that epileptic activity, especially mediated through the amygdala, alters reproductive function, including reduced ovarian cyclicity in females and altered sex steroid hormone levels in both genders. Furthermore, there is an asymmetric activation of the hypothalamus with unilateral amygdala seizures. This may, again, be the basis for the occurrence of different reproductive endocrine disorders described for patients with left-sided or right-sided temporal lobe epilepsy. Copyright © 2015 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.
Albre, Jérôme; Liénard, Marjorie A.; Sirey, Tamara M.; Schmidt, Silvia; Tooman, Leah K.; Carraher, Colm; Greenwood, David R.; Löfstedt, Christer; Newcomb, Richard D.
2012-01-01
Chemical signals are prevalent in sexual communication systems. Mate recognition has been extensively studied within the Lepidoptera, where the production and recognition of species-specific sex pheromone signals are typically the defining character. While the specific blend of compounds that makes up the sex pheromones of many species has been characterized, the molecular mechanisms underpinning the evolution of pheromone-based mate recognition systems remain largely unknown. We have focused on two sets of sibling species within the leafroller moth genera Ctenopseustis and Planotortrix that have rapidly evolved the use of distinct sex pheromone blends. The compounds within these blends differ almost exclusively in the relative position of double bonds that are introduced by desaturase enzymes. Of the six desaturase orthologs isolated from all four species, functional analyses in yeast and gene expression in pheromone glands implicate three in pheromone biosynthesis, two Δ9-desaturases, and a Δ10-desaturase, while the remaining three desaturases include a Δ6-desaturase, a terminal desaturase, and a non-functional desaturase. Comparative quantitative real-time PCR reveals that the Δ10-desaturase is differentially expressed in the pheromone glands of the two sets of sibling species, consistent with differences in the pheromone blend in both species pairs. In the pheromone glands of species that utilize (Z)-8-tetradecenyl acetate as sex pheromone component (Ctenopseustis obliquana and Planotortrix octo), the expression levels of the Δ10-desaturase are significantly higher than in the pheromone glands of their respective sibling species (C. herana and P. excessana). Our results demonstrate that interspecific sex pheromone differences are associated with differential regulation of the same desaturase gene in two genera of moths. We suggest that differential gene regulation among members of a multigene family may be an important mechanism of molecular innovation in sex pheromone evolution and speciation. PMID:22291612
Sex determination and gender expression: Reproductive investment in snails.
Koene, Joris M
2017-02-01
Sex determination is generally seen as an issue of importance for separate-sexed organisms; however, when considering other sexual systems, such as hermaphroditism, sex allocation is a less-binary form of sex determination. As illustrated here, with examples from molluscs, this different vantage point can offer important evolutionary insights. After all, males and females produce only one type of gamete, whereas hermaphrodites produce both. In addition, sperm and accessory gland products are donated bidirectionally. For reciprocal mating, this is obvious since sperm are exchanged within one mating interaction; but even unilaterally mating species end up mating in both sexual roles, albeit not simultaneously. With this in mind, I highlight two factors that play an important role in how reproductive investment is divided in snails: First, the individual's motivation to preferentially donate rather than receive sperm (or vice versa) leads to flexible behavioral performance, and thereby investment, of either sex. Second, due to the presence of both sexual roles within the same individual, partners are potentially able to influence investment in both sexual functions of their partner to their own benefit. The latter has already led to novel insights into how accessory gland products may evolve. Moreover, the current evidence points towards different ways in which allocation to reproduction can be changed in simultaneous hermaphrodites. These often differ from the separate-sexed situation, highlighting that comparison across different sexual systems may help identify commonalities and differences in physiological, and molecular mechanisms as well as evolutionary patterns. Mol. Reprod. Dev. 84: 132-143, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Differential sex-specific effects of oxygen toxicity in human umbilical vein endothelial cells
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang, Yuhao; Lingappan, Krithika
Despite the well-established sex-specific differences in the incidence of bronchopulmonary dysplasia (BPD), the molecular mechanism(s) behind these are not completely understood. Pulmonary angiogenesis is critical for alveolarization and arrest in vascular development adversely affects lung development. Human neonatal umbilical vein endothelial cells (HUVECs) provide a robust in vitro model for the study of endothelial cell physiology and function. Male and Female HUVECs were exposed to room air (21% O{sub 2}, 5% CO{sub 2}) or hyperoxia (95% O{sub 2}, 5% CO{sub 2}) for up to 72 h. Cell viability, proliferation, H{sub 2}O{sub 2} production and angiogenesis were analyzed. Sex-specific differences in the expressionmore » of VEGFR2 and modulation of NF-kappa B pathway were measured. Male HUVECs have decreased survival, greater oxidative stress and impairment in angiogenesis compared to similarly exposed female cells. There is differential expression of VEGFR2 between male and female HUVECs and greater activation of the NF-kappa B pathway in female HUVECs under hyperoxic conditions. The results indicate that sex differences exist between male and female HUVECs in vitro after hyperoxia exposure. Since endothelial dysfunction has a major role in the pathogenesis of BPD, these differences could explain in part the mechanisms behind sex-specific differences in the incidence of this disease. - Highlights: • Cellular sex effects viability and oxidative stress in HUVECs exposed to hyperoxia. • Male HUVECs show greater impairment in angiogenesis compared to female cells. • Sex-specific modulation of VEGFR2 and the NF-kappaB pathway was noted.« less
Bao, Ai-Min; Swaab, Dick F
2011-04-01
During the intrauterine period a testosterone surge masculinizes the fetal brain, whereas the absence of such a surge results in a feminine brain. As sexual differentiation of the brain takes place at a much later stage in development than sexual differentiation of the genitals, these two processes can be influenced independently of each other. Sex differences in cognition, gender identity (an individual's perception of their own sexual identity), sexual orientation (heterosexuality, homosexuality or bisexuality), and the risks of developing neuropsychiatric disorders are programmed into our brain during early development. There is no evidence that one's postnatal social environment plays a crucial role in gender identity or sexual orientation. We discuss the relationships between structural and functional sex differences of various brain areas and the way they change along with any changes in the supply of sex hormones on the one hand and sex differences in behavior in health and disease on the other. Copyright © 2011 Elsevier Inc. All rights reserved.
Tranel, Daniel; Bechara, Antoine
2009-06-01
We have reported previously that there appears to be an intriguing sex-related functional asymmetry of the prefrontal cortices, especially the ventromedial sector, in regard to social conduct, emotional processing, and decision-making, whereby the right-sided sector is important in men but not women and the left-sided sector is important in women but not men. The amygdala is another structure that has been widely implicated in emotion processing and social decision-making, and the question arises as to whether the amygdala, in a manner akin to what has been observed for the prefrontal cortex, might have sex-related functional asymmetry in regard to social and emotional functions. A preliminary test of this question was carried out in the current study, where we used a case-matched lesion approach and contrasted a pair of men cases and a pair of women cases, where in each pair one patient had left amygdala damage and the other had right amygdala damage. We investigated the domains of social conduct, emotional processing and personality, and decision-making. The results provide support for the notion that there is sex-related functional asymmetry of the amygdala in regard to these functions - in the male pair, the patient with right-sided amygdala damage was impaired in these functions, and the patient with left-sided amygdala damage was not, whereas in the female pair, the opposite pattern obtained, with the left-sided woman being impaired and the right-sided woman being unimpaired. These data provide preliminary support for the notion that sex-related functional asymmetry of the amygdala may entail functions such as social conduct, emotional processing, and decision-making, a finding that in turn could reflect (as either a cause or effect) differences in the manner in which men and women apprehend, process, and execute emotion-related information.
Freed, Rachel D; Tompson, Martha C; Wang, Christine H; Otto, Michael W; Hirshfeld-Becker, Dina R; Nierenberg, Andrew A; Henin, Aude
2015-02-01
Previous research has shown that families with a parent who has bipolar disorder (BD) may experience family functioning difficulties. However, the association between family functioning and psychopathology among offspring of parents with BD, and offspring characteristics that may moderate this association, remains poorly understood. This study examined the cross-sectional associations between family functioning (cohesion, expressiveness, and conflict) and psychopathology in 117 offspring (ages 5-18) of 75 parents with BD. We also examined whether age and sex differences moderated these associations. We measured offspring psychopathology by examining current dimensional symptoms and DSM-IV emotional and behavioral disorders. Correlational analyses indicated that higher family conflict and lower cohesion were associated with higher internalizing and externalizing symptoms in offspring. Lower family cohesion was also associated with current offspring mood disorders. Moderation analyses indicated, first, that the link between lower family cohesion and internalizing symptoms was stronger for younger offspring compared to older offspring. Second, higher family conflict and current mood disorder were associated in younger males but not in older males or in females. Results remained the same after controlling for parental anxiety or substance use disorder comorbidity. Our study highlights the importance of accounting for family functioning when working with offspring at risk for BD, while also recognizing that the connections between family functioning and offspring outcomes are complex and differ based on offspring sex and developmental stage. PsycINFO Database Record (c) 2015 APA, all rights reserved.
Takeuchi, Hikaru; Taki, Yasuyuki; Nouchi, Rui; Yokoyama, Ryoichi; Kotozaki, Yuka; Nakagawa, Seishu; Sekiguchi, Atsushi; Iizuka, Kunio; Yamamoto, Yuki; Hanawa, Sugiko; Araki, Tsuyoshi; Makoto Miyauchi, Carlos; Shinada, Takamitsu; Sakaki, Kohei; Nozawa, Takayuki; Ikeda, Shigeyuki; Yokota, Susumu; Daniele, Magistro; Sassa, Yuko; Kawashima, Ryuta
2017-05-15
Brain connectivity is traditionally thought to be important for creativity. Here we investigated the associations of creativity measured by divergent thinking (CMDT) with resting-state functional magnetic imaging (fMRI) measures and their sex differences. We examined these relationships in the brains of 1277 healthy young adults. Whole-brain analyses revealed a significant interaction between verbal CMDT and sex on (a) regional homogeneity within an area from the left anterior temporal lobe (b) on the resting state functional connectivity (RSFC) between the mPFC and the left inferior frontal gyrus and (c) on fractional amplitude of low frequency fluctuations (fALFF) in several distinct areas, including the precuneus and middle cingulate gyrus, left middle temporal gyrus, right middle frontal gyrus, and cerebellum. These interactions were mediated by positive correlations in females and negative correlations in males. These findings suggest that greater CMDT in females is reflected by (a) regional coherence (regional homogeneity) of brain areas responsible for representing and combining concepts as well as (b) the efficient functional connection (RSFC) between the key areas for the default state of cognitive activity and speech production, and (c) greater spontaneous neural activity (fALFF) during the resting of brain areas involved in frontal lobe functions, default cognitive activities, and language functions. Furthermore, these findings suggest that the associations between creativity and resting state brain connectivity patterns are different between males and females. Copyright © 2017 Elsevier Inc. All rights reserved.
Construct validity of the PROMIS® sexual function and satisfaction measures in patients with cancer
2013-01-01
Background With data from a diverse sample of patients either in treatment for cancer or post-treatment for cancer, we examine inter-domain and cross-domain correlations among the core domains of the Patient-Reported Outcomes Measurement Information System Sexual Function and Satisfaction measures (PROMIS® SexFS) and the corresponding domains from conceptually-similar measures of sexual function, the International Index of Erectile Function and the Female Sexual Function Index. Findings Men (N=389) and women (N=430) were recruited from a tumor registry, oncology clinics, and an internet panel. The PROMIS SexFS, International Index of Erectile Function, and Female Sexual Function Index were used to collect participants’ self-reported sexual function. The domains shared among the measures include desire/interest in sexual activity, lubrication and vaginal discomfort/pain (women), erectile function (men), orgasm, and satisfaction. We examined correlations among different domains within the same instrument (discriminant validity) and correlations among similar domains measured by different instruments (convergent validity). Correlations demonstrating discriminant validity ranged from 0.38 to 0.73 for men and 0.48 to 0.74 for women, while correlations demonstrating convergent validity ranged from 0.62 to 0.83 for men and 0.71 to 0.92 for women. As expected, correlations demonstrating convergent validity were higher than correlations demonstrating discriminant validity, with one exception (orgasm for men). Conclusions Construct validity was supported by convergent and discriminant validity in a diverse sample of patients with cancer. For patients with cancer who may or may not have sexual dysfunction, the PROMIS SexFS measures provide a comprehensive assessment of key domains of sexual function and satisfaction. PMID:23497200
Schöning, S; Engelien, A; Kugel, H; Schäfer, S; Schiffbauer, H; Zwitserlood, P; Pletziger, E; Beizai, P; Kersting, A; Ohrmann, P; Greb, R R; Lehmann, W; Heindel, W; Arolt, V; Konrad, C
2007-11-05
Recent observations indicate that sex and level of steroid hormones may influence cortical networks associated with specific cognitive functions, in particular visuo-spatial abilities. The present study probed the influence of sex, menstrual cycle, and sex steroid hormones on 3D mental rotation and brain function using 3-T fMRI. Twelve healthy women and 12 men were investigated. Menstrual cycle and hormone levels were assessed. The early follicular and midluteal phase of the menstrual cycle were chosen to examine short-term cyclical changes. Parietal and frontal areas were activated during mental rotation in both sexes. Significant differences between men and women were revealed in both phases of menstrual cycle. In men we observed a significant correlation of activation levels with testosterone levels in the left parietal lobe (BA 40). In women, a cycle-dependent correlation pattern was observed for testosterone: brain activation correlated with this male hormone only during the early follicular phase. In both cycle phases females' brain activation was significantly correlated with estradiol in frontal and parietal areas. Our study provides evidence that fMRI-related activity during performance of cognitive tasks varies across sex and phases of the menstrual cycle. The variation might be partly explained by better task performance in men, but our results indicate that further explanations like basic neuronal or neurovascular effects modulated by steroid hormones must be considered. Both estradiol and testosterone levels may influence fMRI signals of cognitive tasks, which should affect selection of subjects for future fMRI studies.
Etherton, Mark R; Wu, Ona; Cougo, Pedro; Giese, Anne-Katrin; Cloonan, Lisa; Fitzpatrick, Kaitlin M; Kanakis, Allison S; Boulouis, Gregoire; Karadeli, Hasan H; Lauer, Arne; Rosand, Jonathan; Furie, Karen L; Rost, Natalia S
2017-12-01
Women have worse poststroke outcomes than men. We evaluated sex-specific clinical and neuroimaging characteristics of white matter in association with functional recovery after acute ischemic stroke. We performed a retrospective analysis of acute ischemic stroke patients with admission brain MRI and 3- to 6-month modified Rankin Scale score. White matter hyperintensity and acute infarct volume were quantified on fluid-attenuated inversion recovery and diffusion tensor imaging MRI, respectively. Diffusivity anisotropy metrics were calculated in normal appearing white matter contralateral to the acute ischemia. Among 319 patients with acute ischemic stroke, women were older (68.0 versus 62.7 years; P =0.004), had increased incidence of atrial fibrillation (21.4% versus 12.2%; P =0.04), and lower rate of tobacco use (21.1% versus 35.9%; P =0.03). There was no sex-specific difference in white matter hyperintensity volume, acute infarct volume, National Institutes of Health Stroke Scale, prestroke modified Rankin Scale score, or normal appearing white matter diffusivity anisotropy metrics. However, women were less likely to have an excellent outcome (modified Rankin Scale score <2: 49.6% versus 67.0%; P =0.005). In logistic regression analysis, female sex and the interaction of sex with fractional anisotropy, radial diffusivity, and axial diffusivity were independent predictors of functional outcome. Female sex is associated with decreased likelihood of excellent outcome after acute ischemic stroke. The correlation between markers of white matter integrity and functional outcomes in women, but not men, suggests a potential sex-specific mechanism. © 2017 American Heart Association, Inc.
Sex differences in brain response to anticipated and experienced visceral pain in healthy subjects.
Kano, Michiko; Farmer, Adam D; Aziz, Qasim; Giampietro, Vincent P; Brammer, Michael J; Williams, Steven C R; Fukudo, Shin; Coen, Steven J
2013-04-15
Women demonstrate higher pain sensitivity and prevalence of chronic visceral pain conditions such as functional gastrointestinal disorders than men. The role of sex differences in the brain processing of visceral pain is still unclear. In 16 male and 16 female healthy subjects we compared personality, anxiety levels, skin conductance response (SCR), and brain processing using functional MRI during anticipation and pain induced by esophageal distension at pain toleration level. There was no significant difference in personality scores, anxiety levels, SCR, and subjective ratings of pain between sexes. In group analysis, both men and women demonstrated a similar pattern of brain activation and deactivation during anticipation and pain consistent with previous reports. However, during anticipation women showed significantly greater activation in the cuneus, precuneus, and supplementary motor area (SMA) and stronger deactivation in the right amygdala and left parahippocampal gyrus, whereas men demonstrated greater activation in the cerebellum. During pain, women demonstrated greater activation in the midcingulate cortex, anterior insula, premotor cortex, and cerebellum and stronger deactivation in the caudate, whereas men showed increased activity in the SMA. The pattern of brain activity suggests that, during anticipation, women may demonstrate stronger limbic inhibition, which is considered to be a cognitive modulation strategy for impending painful stimulation. During pain, women significantly activate brain areas associated with the affective and motivation components of pain. These responses may underlie the sex differences that exist in pain conditions, whereby women may attribute more emotional importance to painful stimuli compared with men.
Intravenous Nicotine Self-Administration in Smokers: Dose-Response Function and Sex Differences.
Jensen, Kevin P; DeVito, Elise E; Valentine, Gerald; Gueorguieva, Ralitza; Sofuoglu, Mehmet
2016-07-01
Sex differences in the sensitivity to nicotine may influence vulnerability to tobacco dependence. The goal of this study was to investigate the dose-response function for the reinforcing and subjective effects of intravenous nicotine in male and female smokers. Tobacco-dependent subjects (12 male and 14 female) participated in four experimental sessions in which they received sample infusions of saline and nicotine (0.1, 0.2, 0.3, or 0.4 mg doses) in a randomized double-blind crossover design. During each session, subjects first received the sample infusions, and heart rate (HR), blood pressure, and subjective stimulatory, pleasurable and aversive responses were monitored. Immediately following the sample infusions, subjects self-administered either nicotine or saline in six double-blind forced-choice trials. A sex by dose interaction was observed in the nicotine choice paradigm. Nicotine self-administration rate was negatively correlated with nicotine dose in males (males displayed choice preference for low doses of nicotine over high doses of nicotine), but no significant relationship between dose and choice preference was evident in females. Relative to placebo, sample doses of nicotine increased heart rate and blood pressure, and induced stimulatory, pleasurable, and aversive subjective effects. Diastolic blood pressure increased dose dependently in males, but not in females. These findings, which demonstrate sex differences in nicotine self-administration for doses that are near to the reinforcement threshold, suggest that male and female smokers may respond differently to the changes in nicotine doses available for self-administration.
Onishi, Makiko; Yamanaka, Ko; Miyamoto, Yasunori; Waki, Hidefumi; Gouraud, Sabine
2018-04-01
Arterial pressure (AP) is lower in premenopausal women than in men of a similar age. Premenopausal women exhibit a lower sympathetic activity and a greater baroreceptor reflex; however, mechanisms controlling sex differences in blood pressure regulation are not well understood. We hypothesized that different neuronal functions in the cardiovascular centers of the brains of men and women may contribute to the sex difference in cardiovascular homeostasis. Our previous studies on male spontaneously hypertensive rats (SHRs) and their normotensive counterparts, Wistar Kyoto (WKY) rats, revealed that the gene-expression profile of the nucleus tractus solitarius (NTS), a region of the medulla oblongata that is pivotal for regulating the set point of AP, is strongly associated with AP. Thus, we hypothesized that gene-expression profiles in the rat NTS are related to sex differences in AP regulation. Because female SHRs clearly exhibit lower AP than their male counterparts of a similar age, we investigated whether SHR NTS exhibits sex differences in gene expression by using microarray and RT-qPCR experiments. The transcript for transient receptor potential cation channel subfamily V member 4 ( Trpv4) was found to be upregulated in SHR NTS in females compared with that in males. The channel was expressed in neurons and glial cells within NTS. The TRPV4 agonist 4-alpha-phorbol-12,13-didecanoate (4α-PDD) decreased blood pressure when injected into NTS of rats. These findings suggest that altered TRPV4 expression might be involved in the sex differences in blood pressure regulation.
Differences in shame and pride as a function of children's gender and task difficulty.
Lewis, M; Alessandri, S M; Sullivan, M W
1992-06-01
3-year-old children were presented with easy and difficult tasks and their emotional responses of shame and pride were observed. No shame was shown when subjects succeeded on the tasks and no pride was shown when they failed. Significantly more shame was shown when subjects failed easy tasks than when they failed difficult tasks, and significantly more pride was shown when subjects succeeded on difficult than on easy tasks. While there were no sex differences in task failures, girls showed more shame than boys. There were no sex differences in pride when subjects succeeded.