Sex Differences In Emotion Research Articles

Identifying sex differences in EEG-based emotion recognition using graph convolutional network with attention mechanism

Objective. Sex differences in emotions have been widely perceived via self-reports, peripheral physiological signals and brain imaging techniques. However, how sex differences are reflected in the electroencephalography (EEG) neural patterns of emotions remains unresolved. In this paper, we detect sex differences in emotional EEG patterns, investigate the consistency of such differences in various emotion datasets across cultures, and study how sex as a factor affects the performance of EEG-based emotion recognition models. Approach. We thoroughly assess sex differences in emotional EEG patterns on five public datasets, including SEED, SEED-IV, SEED-V, DEAP and DREAMER, systematically examine the sex-specific EEG patterns for happy, sad, fearful, disgusted and neutral emotions, and implement deep learning models for sex-specific emotion recognition. Main results. (1) Sex differences exist in various emotion types and both Western and Eastern cultures; (2) The emotion patterns of females are more stable than those of males, and the patterns of happiness from females are in sharp contrast with the patterns of sadness, fear and disgust, while the energy levels are more balanced for males; (3) The key features for emotion recognition are mainly located at the frontal and temporal sites for females and distributed more evenly over the whole brain for males, and (4) the same-sex emotion recognition models outperform the corresponding cross-sex models. Significance. These findings extend efforts to characterize sex differences in emotional brain activation, provide new physiological evidence for sex-specific emotion processing, and reinforce the message that sex differences should be carefully considered in affective research and precision medicine.

Sex differences in emotion- and reward-related neural responses predicting increases in substance use in adolescence

Adolescent substance use is a significant public health problem and there is a need for effective substance use preventions. To develop effective preventions, it is important to identify neurobiological risk factors that predict increases in substance use in adolescence and to understand potential sex differences in risk mechanisms. The present study used functional magnetic resonance imaging and hierarchical linear modeling to examine negative emotion- and reward-related neural responses in early adolescence predicting growth in substance use to middle adolescence in 81 youth, by sex. Adolescent neural responses to negative emotional stimuli and monetary reward receipt were assessed at age 12–14. Adolescents reported on substance use at age 12–14 and at 6 month, and 1, 2, and 3 year follow-ups. Adolescent neural responses did not predict initiation of substance use (yes/no), but, among users, neural responses predicted growth in substance use frequency. For girls, heightened right amygdala responses to negative emotional stimuli in early adolescence predicted growth in substance use frequency through middle adolescence. For boys, blunted left nucleus accumbens and bilateral ventromedial prefrontal cortex responses to monetary reward predicted growth in substance use frequency. Findings suggest different emotion and reward-related predictors of the development of substance use for adolescent girls versus boys.

Sex Differences in Emotions and Eating Behaviors among People Affected by Obesity.

Relatively little research has examined sex differences among people affected by obesity. The aim of this study is to assess the relationship between negative emotions and eating behaviors, taking into account the role of biological sex. The final sample consists of 200 candidates for bariatric surgery, 62 males (31%) and 138 females (69%), aged from 18 to 60 years (M = 40.71; SD = 11.30). Participants were screened with the Binge Scale Questionnaire (BSQ) and individually evaluated with the Eating Disorder Inventory (EDI) and the Profile of Mood States (POMS). Correlations were calculated by splitting the sample by sex. Analyses of the relationship between negative emotions and eating behavior showed a large number of correlations in the sample of women and few correlations in men. The differences between women and men with obesity suggest the need for a different theoretical construct that explains the differentiated mechanisms of functioning and lays the foundations for specific therapeutic paths.

Developmental Sex Differences in Negative Emotion Decision-Making Dynamics: Computational Evidence and Amygdala-Prefrontal Pathways.

Sex differences in human emotion and related decision-making behaviors are recognized, which can be traced back early in development. However, our understanding of their underlying neurodevelopmental mechanisms remains elusive. Using developmental functional magnetic resonance imaging and computational approach, we investigated developmental sex differences in latent decision-making dynamics during negative emotion processing and related neurocognitive pathways in 243 school-aged children and 78 young adults. Behaviorally, girls exhibit higher response caution and more effective evidence accumulation, whereas boys show more impulsive response to negative facial expression stimuli. These effects parallel sex differences in emotion-related brain maturity linking to evidence accumulation, along with age-related decrease in emotional response in the basolateral amygdala and medial prefrontal cortex (MPFC) in girls and an increase in the centromedial amygdala (CMA) in boys. Moreover, girls exhibit age-related decreases in BLA-MPFC coupling linked to evidence accumulation, but boys exhibit increases in CMA-insula coupling associated with response caution. Our findings highlight the neurocomputational accounts for developmental sex differences in emotion and emotion-related behaviors and provide important implications into the neurodevelopmental mechanisms of sex differences in latent emotional decision-making dynamics. This informs the emergence of sex differences in typical and atypical neurodevelopment of children's emotion and related functions.

Androgyny eliminates sex differences in emotional reactivity: ERP and network coupling evidences

The role of gender role in interpreting sex differences in emotion is unknown. The present study examined how gender role moderates sex differences in emotional reactivity. Event-related potentials (ERP) were recorded in sixty-eight subjects with typical or androgynous gender roles when they passively observed neutral and negative pictures. Behaviorally, typical females (feminine females) reported higher emotional rating than typical males (masculine males), while androgynous males and androgynous females reported no significant differences. Electrophysiologically, we found higher late positive potential (LPP) amplitude in typical females compared to typical males, while this pattern of sex difference was absent in androgynous subjects. The network analysis of EEG data indicates that typical males showed enhanced network coupling strengths between frontal/prefrontal and parietal areas than typical females, which was again absent in androgynous subjects. These findings suggest that gender role is an important determinant in the interpretation of sex differences in emotional reactivity.

Sex effects on structural maturation of the limbic system and outcomes on emotional regulation during adolescence

Though adolescence is a time of emerging sex differences in emotions, sex-related differences in the anatomy of the maturing brain has been under-explored over this period. The aim of this study was to investigate whether puberty and sexual differentiation in brain maturation could explain emotional differences between girls and boys during adolescence. We adapted a dedicated longitudinal pipeline to process structural and diffusion images from 335 typically developing adolescents between 14 and 16 years. We used voxel-based and Regions of Interest approaches to explore sex and puberty effects on brain and behavioral changes during adolescence. Sexual differences in brain maturation were characterized by amygdala and hippocampal volume increase in boys and decrease in girls. These changes were mediating the sexual differences in positive emotional regulation as illustrated by positive attributes increase in boys and decrease in girls. Moreover, the differential maturation rates between the limbic system and the prefrontal cortex highlighted the delayed maturation in boys compared to girls. This is the first study to show the sex effects on the differential cortico/subcortical maturation rates and the interaction between sex and puberty in the limbic system maturation related to positive attributes, reported as being protective from emotional disorders.

A daily diary study on adolescent emotional experiences: Measurement invariance and developmental trajectories.

Adolescence is an important time for emotional development. Recently, daily diary methods are increasingly employed in research on emotional development and are used to explore the development of and sex differences in emotions during adolescence. However, before drawing conclusions about sex differences and developmental trends, one needs to ensure that the same construct is measured across sex and time. The present study tested measurement invariance of daily emotion assessments across sex, short-term (days within weeks) and long-term periods (days across years) in a sample of 394 adolescents (55.6% male) that were followed from ages 13 to 18. Moreover, the study examined the developmental trajectories of adolescent emotional experiences. Adolescents rated their daily emotions (happiness, anger, sadness, anxiety) during each day of a normal school week (Monday to Friday) for 3 weeks per year for 5 years (i.e., 15 weeks × 5 days = 75 assessments in total). Measurement invariance analyses suggest that the measurement of adolescent daily mood was invariant between boys and girls and across shorter and longer time intervals. Moreover, latent growth curve analyses showed that happiness decreased from early to middle adolescence, whereas anger, sadness, and anxiety increased. Anger returned to baseline toward late adolescence. In contrast, the decrease of happiness and the increase of anxiety leveled off without reversing, whereas sadness continued to increase. The discussion highlights the implications of measurement invariance in research on individual and developmental differences and discusses the findings in light of normative emotional development. (PsycINFO Database Record

Relevance of Stress and Female Sex Hormones for Emotion and Cognition

There are clear sex differences in incidence and onset of stress-related and other psychiatric disorders in humans. Yet, rodent models for psychiatric disorders are predominantly based on male animals. The strongest argument for not using female rodents is their estrous cycle and the fluctuating sex hormones per phase which multiplies the number of animals to be tested. Here, we will discuss studies focused on sex differences in emotionality and cognitive abilities in experimental conditions with and without stress. First, female sex hormones such as estrogens and progesterone affect emotions and cognition, contributing to sex differences in behavior. Second, females respond differently to stress than males which might be related to the phase of the estrous cycle. For example, female rats and mice express less anxiety than males in a novel environment. Proestrus females are less anxious than females in the other estrous phases. Third, males perform in spatial tasks superior to females. However, while stress impairs spatial memory in males, females improve their spatial abilities, depending on the task and kind of stressor. We conclude that the differences in emotion, cognition and responses to stress between males and females over the different phases of the estrous cycle should be used in animal models for stress-related psychiatric disorders.

Boys don't cry: Cognitive load and priming increase stereotypic sex differences in emotion memory

The results of three experiments provide evidence that the relative accessibility of stereotypes about sex difference influences people's memory of very recent emotions. Being under high rather than low cognitive load caused females compared with males to recall experiencing more intense emotional reactions to saddening stimuli (Experiments 1 and 2), and relatively less intense reactions to angering stimuli (Experiment 2). Being directly primed with stereotypes about sex differences and being under high cognitive load both caused females to recall more intense reactions to saddening stimuli compared with females who were neither primed with stereotypes nor under cognitive load (Experiment 3). These results imply that the relative accessibility of stereotypes influences memories of emotion in a manner similar to stereotypes' influence on social perception. Implications of these findings for theories of emotion memory and for self-perpetuating stereotypes about emotional sex differences are discussed.

Prepubertal gonadotropin-releasing hormone analog leads to exaggerated behavioral and emotional sex differences in sheep

In mammals, sex specialization is reflected by differences in brain anatomy and function. Measurable differences are documented in reproductive behavior, cognition, and emotion. We hypothesized that gonadotropin-releasing hormone (GnRH) plays a crucial role in controlling the extent of the brain's sex specificity and that changes in GnRH action during critical periods of brain development, such as puberty, will result in altered sex-specific behavioral and physiological patterns. We blocked puberty in half of the 48 same-sex Scottish mule Texel cross sheep twins with GnRH analog (GnRHa) goserelin acetate every 3weeks, beginning just before puberty. To determine the effects of GnRHa treatment on sex-specific behavior and emotion regulation in different social contexts, we employed the food acquisition task (FAT) and measurement of heart rate variability (HRV). ANOVA revealed significant sex and sex×treatment interaction effects, suggesting that treated males were more likely to leave their companions to acquire food than untreated, while the opposite effect was observed in females. Concordant results were seen in HRV; treated males displayed higher HRV than untreated, while the reverse pattern was found in females, as shown by significant sex and sex×treatment interaction effects. We conclude that long-term prepubertal GnRHa treatment significantly affected sex-specific brain development, which impacted emotion and behavior regulation in sheep. These results suggest that GnRH is a modulator of cognitive function in the developing brain and that the sexes are differentially affected by GnRH modulation.

Are There Sex Differences in Affective Modulation of Spinal Nociception and Pain?

Sex differences in the processing and experience of emotion exist. The present study examined whether sex differences in emotion lead to sex differences in affective modulation of pain and spinal nociception (assessed by nociceptive flexion reflex, NFR). Participants were healthy men (n = 47) and women (n = 73). Prior to affective modulation testing, electrocutaneous pain sensitivity was assessed (NFR threshold, pain threshold, pain tolerance). Affective modulation of pain and NFR was then assessed by presenting pictures that vary in emotional valence and arousal (mutilation, attack, death, neutral, families, adventure, erotica) during which suprathreshold electrocutaneous stimulations were delivered. Subjective emotional reactions were assessed after every picture, and nociceptive reactions were assessed after every suprathreshold stimulus. Results indicated women had greater pain sensitivity and also responded more negatively to attack pictures and less positively to erotic pictures. But despite these differences, affective modulation of pain/NFR was not moderated by sex: erotic pictures inhibited pain/NFR and mutilation pictures enhanced pain/NFR. Together, this implies subjective emotional experience does not completely mediate picture-evoked modulation of pain/NFR, a supposition that was further supported by exploratory analyses that demonstrated picture-evoked modulation of pain/NFR was present even after controlling for intra- and inter-individual differences in emotional reactions to pictures. Implications and limitations of these findings are discussed. Evidence suggests that women are more sensitive to experimental and clinical pain, but the mechanisms contributing to these sex differences are poorly understood. Affective processes are known to play a role in regulating pain signaling and pain experience; therefore, the present study examined whether sex differences in affective experience contribute to sex differences in pain. Results indicate that in healthy individuals affective processes may not contribute to sex differences in pain.

Beyond our origin: Adding social context to an explanation of sex differences in emotion expression

AbstractVigil's socio-relational framework of sex differences in emotional expressiveness emphasizes general sex differences in emotional responding, but largely ignores the social context in which emotions are expressed. There is much empirical evidence showing that sex differences in emotion displays are flexible and a function of specific social roles and demands, rather than a reflection of evolutionary-based social adjustments.

Separating production from perception: Perceiver-based explanations for sex differences in emotion

AbstractIn this commentary, we review evidence that production-based (perceiver-independent) measures reveal few consistent sex differences in emotion. Further, sex differences in perceiver-based measures can be attributed to retrospective or dispositional biases. We end by discussing an alternative view that women might appear to be more emotional because they are more facile with emotion language.

Sex differences in emotionality in C3H/HeH mice, with hypogonadal mutant to distinguish activational effects of gonadal hormones

The C3H/HeH mouse strain has a mutant hypogonadal (hpg) variant, providing an animal model to examine the activational effects of sex hormones because reproductive maturation is arrested at a neonatal stage. Thus in the adult mouse, the circulating concentrations of sex steroids are extremely low. The present study used a series of tests to distinguish sex differences in behaviour: open field, locomotor activity, hyponeophagia, and novel location recognition. The results showed some evidence for a role of sex hormones in emotionality underscoring the potential utility of the hpg model, to distinguish activational effects in the C3H/HeH strain. However, the direction that the sex differences took varied by task: whilst males showed the predicted sex difference of relatively greater anxiety in the open field, hyponeophagia tests suggested higher emotionality in females. The hpg mice of both sexes showed a reduction in anxiety measured as hyponeophagia. Overall it can be concluded that this set of experiments supports the potential of the hpg model to investigate hormonal influences on emotionality.

Sex differences in the time course of emotion.

Conventional wisdom holds that women are more "emotional" than men. However, research evidence suggests that sex differences in emotion are considerably more complex. The authors tested hypotheses about sex differences in the engagement of the approach and avoidance motivational systems thought to underpin emotional responses. The authors measured reported emotional experience and startle response magnitude both during the presentation and after the offset of emotional stimuli that engage these motivational systems to assess whether men and women differ in their patterns of immediate response to emotional stimuli and in their patterns of recovery from these responses. Our findings indicated that women were more experientially reactive to negative, but not positive, emotional pictures compared to men, and that women scored higher than men on measure of aversive motivational system sensitivity. Although both men and women exhibited potentiation of the startle response during the presentation of negative pictures relative to neutral pictures, only women continued to show this relative potentiation during the recovery period, indicating that women were continuing to engage the aversive motivational system after the offset of negative emotional pictures.

Do sex differences in emotionality mediate sex differences in traits of psychosis-proneness?

The aim of the study was to determine if sex differences in emotionality might account for sex differences in distinct traits of proneness to psychosis (or "schizotypy"). Females report higher levels of "positive" schizotypy (e.g., magical thinking) than males, along with a tendency toward greater schizotypal disorganisation, whereas males report higher levels of "negative" schizotypal traits, such as social anxiety (Jackson & Claridge, 1991; Raine, 1992). Given the affect-oriented nature of "negative" schizotypal traits, we tested the hypothesis that higher levels of "negative" schizotypy among males would be accounted for by more general sex differences in emotionality; that is, by less frequent and less intense emotional experiences. A total of 81 student participants were administered the Cognitive-Perceptual Deficits, the Disorganisation, and the Interpersonal Deficits components of Raine's (1991) Schizotypal Personality Questionnaire (SPQ), indexing respectively, "positive" schizotypy, schizotypal disorganisation, and "negative" schizotypy. Frequency of emotional experience was assessed using the Emotionality subscale (Buss & Plomin, 1984) and intensity, the Affect Intensity Measure (Larsen & Diener, 1987). As predicted, males scored significantly higher than females on the SPQ Interpersonal Deficits component but no sex differences emerged for the other two components. Males reported significantly less intense, although not less frequent, experiences than females. A reduced intensity of positive emotions in particular was found to mediate the sex difference in "negative" schizotypy. Our results suggest that a less intense experience of positive affect might contribute to males' propensity to develop negative symptoms should a schizophrenic breakdown occur.

Sex Differences in Emotion

This article examines the findings of several reviews of the empirical literature on biological sex and emotion, focusing on the degree to which perceived sex differences in emotionality are, and in most cases are not, supported while at the same time addressing the implications this body of research has for counseling psychologists. This article also explores potential explanations, such as gender role socialization or situational influences, for the profession’s continued acceptance of large innate sex-based affective differences. Finally, the third section discusses several concerns this continued acceptance raises for the practice of counseling, whereas the last section offers a research agenda building on the review presented herein.

Are Women the “More Emotional” Sex? Evidence From Emotional Experiences in Social Context

The present study examined whether sex differences in emotion are related to the social context and addressed differences between global, retrospective, and on-line, momentary self-descriptions of emotional experience and expression. Participants provided global, retrospective descriptions of their emotional characteristics at an initial session, and then provided momentary emotion ratings as well as details about the social context in which they experienced their emotions over a one-week period. We predicted and found that sex-related differences in emotion in global self-descriptions, but not in the averaged momentary ratings of emotion. Furthermore, only sex of the interaction partner elicited sex differences in emotionality; participants experienced and expressed more emotion when in opposite-sex dyads. Although most of the other context variables were themselves associated with emotional experience or expression, suggesting that they were emotionally evocative, none emerged as elicitors of sex differences in emotional experience; felt intimacy in the interaction was associated with sex differences in ratings of emotional expression. Together, the findings present certain caveats to the widely held belief that women are the ''more emotional'' sex.

Sex differences in emotion: expression, experience, and physiology.

Although previous studies of emotional responding have found that women are more emotionally expressive than men, it remains unclear whether men and women differ in other domains of emotional response. We assessed the expressive, experiential, and physiological emotional responses of men and women in 2 studies. In Study 1, undergraduates viewed emotional films. Compared with men, women were more expressive, did not differ in reports of experienced emotion, and demonstrated different patterns of skin conductance responding. In Study 2, undergraduate men and women viewed emotional films and completed self-report scales of expressivity, gender role characteristics, and family expressiveness. Results replicated those from Study 1, and gender role characteristics and family expressiveness moderated the relationship between sex and expressivity.

Sex differences in emotion: Expression, experience, and physiology.

Sex differences in emotion: Expression, experience, and physiology.