The standardization of a new Explicit Pornographic Picture Set (EPPS)

Pictures with affective content have been extensively used in scientific studies of emotion and sexuality. However, only a few standardized picture sets have been developed that offer explicit images, with most lacking pornographic pictures depicting diverse sexual practices. This study aimed to fill this gap through developing a standardized affective set of diverse pornographic pictures (masturbation, oral sex, vaginal sex, anal sex, group sex, paraphilia) of same-sex and opposite-sex content, offering dimensional affective ratings of valence, arousal, and dominance, as well as co-elicited discrete emotions (disgust, moral and ethical acceptance). In total, 192 pornographic pictures acquired from online pornography platforms and 24 control IAPS images have been rated by 319 participants (Mage = 22.66, SDage = 4.66) with self-reported same- and opposite-sex sexual attraction. Stimuli were representative of the entire affective space, including positively and negatively perceived pictures. Participants showed differential affective perception of pornographic pictures according to gender and sexual attraction. Differences in affective ratings related to participants' gender and sexual attraction, as well as stimuli content (depicted sexual practices and sexes). From the stimuli set, researchers can select explicit pornographic pictures based on the obtained affective ratings and technical parameters (i.e., pixel size, luminosity, color space, contrast, chromatic complexity, spatial frequency, entropy). The stimuli set may be considered a valid tool of diverse explicit pornographic pictures covering the affective space, in particular, for women and men with same- and opposite-sex sexual attraction. This new explicit pornographic picture set (EPPS) is available to the scientific community for non-commercial use.

Symbiosexual Attraction: An Integrated Mixed-Methods Study

A recent review of cultural and academic discourse presented evidence that some people experience attraction to two (or more) people in a preexisting relationship. This phenomenon, symbiosexuality, is understudied in the field of sexuality. Lack of recognition and validation for this attraction, including in the polyamorous community, may be negatively impacting those who experience symbiosexual attraction. I conducted an integrated mixed-methods analysis of secondary data from the 2023 The Pleasure Study to learn more about symbiosexual attraction. Findings from this study support the hypothesis that people experience symbiosexual attraction, which they describe as an attraction to the energy, multidimensionality, and power shared between people in relationships. Further, findings from this study indicate that a diverse group of people experience symbiosexual attraction and, while unanticipated, symbiosexual attraction can be a strong, frequent, and/or pervasive experience. These findings push the boundaries of the concepts of desire and sexual orientation in sexuality studies and challenge the ongoing invisibility and invalidation of and stigma and discrimination against such attractions, within both the polyamorous community and our broader mononormative culture.

Sexual Attraction and Non-Suicidal Self-Harm: The Role of Stressors and Psychological Mediators

Non-suicidal self-harm (NSSH) is a serious concern for the well-being of youth. Stressors relate to greater NSSH risk, such as being non-heterosexual in a heteronormative society. Other stressors may include traumatic experiences. These relationships may be mediated by psychological factors (depressed mood, anxiety, anger, and self-esteem) as well as contextual factors (support from parents and peers). The purpose of this study was to examine NSHH ideation and behavior among Icelandic youth, as well as relationships with stressors and mediators. Students in Icelandic high schools (N = 8921, 50.8% female) completed an in-class survey in the year 2016. Results showed an elevated risk of NSSH ideation and behavior among bisexual and homosexual youth. Mediation analyses showed that, for girls, being bisexual related to greater NSSH ideation and behavior, and these relationships were mediated by depressed mood, anger, and self-esteem, as well as by support from parents and peers. For boys, however, both homosexual and bisexual attraction related to greater risk for NSSH ideation and behavior, which was mediated by depressed mood, anger, and self-esteem. These results suggest that NSSH risk factors vary by gender and, therefore, they may benefit from different interventions to stop and prevent this behavior. This is the first study of its kind in Iceland, where sexual minority stress may need further study within the Nordic context.

A Comparison of Mate Preferences in Asexual and Allosexual Adults

Asexuality is a sexual orientation characterized by a lack of sexual attraction. Sexual attraction is likely associated with preferences for certain characteristics in romantic partners, such as physical attractiveness. Preferred partner characteristics can be influenced by an individual's sexual orientation, gender, and age. Allosexual (N = 239; male = 48, female = 181, other = 4; Age M = 20.48 years) and asexual participants (N = 149; male = 36, female = 88, other = 23; Age M = 25.54 years) recruited from a pool of psychology students and through online asexual communities were presented with a survey in which a total of 388 participants rated 13 characteristics according to how desirable they were in a potential long-term romantic partner. Characteristics that are related to physical attractiveness were predicted to be rated lower by asexual participants than by allosexual participants. Asexual participants rated the desire to have children as being less desirable in a romantic partner than allosexual participants did. However, preferences for other traits, such as exciting personality, creative and artistic, and religious, were dependent on interactions of gender and attraction to men or women. Because asexual individuals report generally lower levels of sexual attraction, it will be important for future research to consider romantic attraction as a more nuanced measure than sexual orientation alone when considering sex differences in asexual and allosexual populations.

Digit Ratio (2D:4D; Right-Left 2D:4D) and Multiple Phenotypes for Same-Sex Attraction: The BBC Internet Study Revisited

Same-sex attraction may be linked to low prenatal androgen (in men) and high prenatal androgen (in women). Digit ratio (2D:4D) is thought to be a negative correlate of prenatal androgen and right-left 2D:4D (Dr-l) to reflect lateralized differences in sensitivity to prenatal androgen. Lower 2D:4D has been reported for lesbians compared to heterosexuals, but links to high 2D:4D in gay men are less clear. The largest study thus far (the BBC Internet study) found no significant difference between the 2D:4D of lesbians and heterosexual women but a higher 2D:4D in gay men compared to heterosexual men. Here we consider the possibility that low and high prenatal androgen is associated with same-sex attraction in men (n = 108,779) and women (n = 87,742), resulting in more than two phenotypes. We examined the associations between 2D:4D, Dr-l, and same-sex attraction scores in the BBC Internet study. In contrast to the earlier report, which considered sexual orientation in categories, there were positive linear associations in men (right and left 2D:4D, but not Dr-l) and negative linear associations in women (right 2D:4D and Dr-l, but not left 2D:4D). There were no curvilinear relationships for right and left 2D:4D. However, Dr-l showed a U-shaped association with same-sex attraction in men. Thus, (1) high prenatal androgen may be implicated in female homosexuality, while both low and high prenatal androgen may be implicated in male homosexuality, and (2) large side differences in sensitivity to androgen may be associated with elevated same-sex attraction in men.

Is sexual attraction and place of origin a moderator of sex in pornography consumption? Cross-sectional study on a representative sample of young adults

BACKGROUND

Pornography consumption is higher in men, but we do not know if this association can be modified by different variables, such as sexual attraction and place of origin. Given the impact pornography has on minors, there are limited studies that analyze the use of pornography in representative samples of the adult population. The aim was analyze the prevalence and factors associated with using pornography in young adult men and women, living in Spain, with different sexual attractions and different places of birth.

METHODS

Cross-sectional study with an online survey conducted with 2515 men and women aged between 18 and 35 years of age. The prevalence of pornography consumption is described and analyzed in the total sample and stratified by sex, according to socio-demographic and sexual attraction variables. The association between covariates and pornography consumption at some point in life was estimated with prevalence ratios (PR) obtained with the Poisson models of robust variance.

DEPENDENT VARIABLE

voluntarily using pornography at some point in life. Socio-demographic variables were included in the analysis: age, sex, level of education, place of birth. Sexual attraction was also analyzed.

RESULTS

In Spain, 94.7% of men between 18 and 34 years and 74.6% of women have voluntarily used pornography at some point in their life. The mean age to start using it is earlier in men [Mean:14.2; Standard Deviation (SD):2.3]. Bisexual/homosexual attraction (reference: heterosexual) increases the probability of using pornography in women [(PR (95%CI): 1.30 (1.22; 1.38)]. Yet this is not observed in men. In both sexes, the probability of using pornography increases with age [(PR (95%CI): 1.01(1.00; 1.01)] and coming from abroad (reference: native), being the effect of country of birth significantly higher in women [(PR (95%CI): 1.17 (1.09; 1.26)] than in men [(PR (95%CI): 1.04 (1.01; 1.07).

CONCLUSIONS

Public health programmes aimed at improving affective-sexual health should consider the high use of pornography among young adults in Spain, as well as those variables that increase its use.

Understanding Attraction, Behavior, and Identity in the Asexual Community

Models of sexuality have evolved substantially in the past several decades through the inclusion of new aspects which were previously overlooked. Components such as romantic attraction and behavior have also traditionally been included in models of sexuality. However, romantic and sexual orientations do not coincide for all individuals. A population for which this is true and one that has developed a robust language for discussing romantic orientation is the asexual community. The current study aimed to explore romantic and sexual orientation through patterns found within the factors of attraction, behavior, and identity in the asexual community. The current sample composed of individuals who identified as asexual (N = 306, M_age = 27.1) was 61% female, 13% non-binary, and 10% self-described or used multiple labels. Within this sample, aspects of sexual and romantic orientations and experiences were measured, including fluidity, the quantity and type of self-identified labels, desire for romance or sex, and the role of contextual influences on these experiences. These aspects were used as the primary characteristics to construct participant profiles, both complete profiles and factor specific (attraction, behavior, identity). t-distributed stochastic neighbor embedding (tSNE) was used to find patterns of similarity between individual participant profiles. Overall, it appeared that attraction was the factor most closely associated with overall experiences; however, substantial variability existed between participants. These findings provide a mechanism for better understanding of some nuances of romantic and sexual orientation and may be a useful first step toward future inquiry and hypothesis generation.

Sexual attraction to visual sexual stimuli in association with steroid hormones across menstrual cycles and fertility treatment

BACKGROUND

Steroid hormones (i.e., estradiol, progesterone, and testosterone) are considered to play a crucial role in the regulation of women's sexual desire and sexual attraction to sexual stimuli throughout the menstrual cycle. However, the literature is inconsistent, and methodologically sound studies on the relationship between steroid hormones and women's sexual attraction are rare.

METHODS

This prospective longitudinal multisite study examined estradiol, progesterone, and testosterone serum levels in association with sexual attraction to visual sexual stimuli in naturally cycling women and in women undergoing fertility treatment (in vitro fertilization, IVF). Across ovarian stimulation of fertility treatment, estradiol reaches supraphysiological levels, while other ovarian hormones remain nearly stable. Ovarian stimulation hence offers a unique quasi-experimental model to study concentration-dependent effects of estradiol. Hormonal parameters and sexual attraction to visual sexual stimuli assessed with computerized visual analogue scales were collected at four time points per cycle, i.e., during the menstrual, preovulatory, mid-luteal, and premenstrual phases, across two consecutive menstrual cycles (n = 88 and n = 68 for the first and second cycle, respectively). Women undergoing fertility treatment (n = 44) were assessed twice, at the beginning and at the end of ovarian stimulation. Sexually explicit photographs served as visual sexual stimuli.

RESULTS

In naturally cycling women, sexual attraction to visual sexual stimuli did not vary consistently across two consecutive menstrual cycles. While in the first menstrual cycle sexual attraction to male bodies, couples kissing, and at intercourse varied significantly with a peak in the preovulatory phase, (all p ≤ 0.001), there was no significant variability across the second cycle. Univariable and multivariable models evaluating repeated cross-sectional relationships and intraindividual change scores revealed no consistent associations between estradiol, progesterone, and testosterone and sexual attraction to visual sexual stimuli throughout both menstrual cycles. Also, no significant association with any hormone was found when the data from both menstrual cycles were combined. In women undergoing ovarian stimulation of IVF, sexual attraction to visual sexual stimuli did not vary over time and was not associated with estradiol levels despite intraindividual changes in estradiol levels from 122.0 to 11,746.0 pmol/l with a mean (SD) of 3553.9 (2472.4) pmol/l.

CONCLUSIONS

These results imply that neither physiological levels of estradiol, progesterone, and testosterone in naturally cycling women nor supraphysiological levels of estradiol due to ovarian stimulation exert any relevant effect on women's sexual attraction to visual sexual stimuli.

Paraphilic Sexual Attraction to Males Without Genitals Is Associated with Traumatic Childhood Experience, Body Image, and Thoughts/Behaviors Related to Genital Ablation

In rare cases, some male individuals are sexually attracted to men who have their genitals removed. We investigate here if paraphilic attraction to men without genitals was associated with childhood experience, body image, and thoughts/behaviors related to body modification. An online survey, consisting of both validated questionnaires and questions developed by our team, was launched on the Eunuch Archive and MTurk websites. Out of 875 participants, 48.5 and 32.2% reported being attracted to males without testicles or without a penis, respectively; 49.7 and 31.0% felt they would themselves be attractive without testicles and without a penis, respectively. In terms of body modification, many reported having tattoos (19.0%) and piercings (26.1%). About half (48.3%) had played as children with male action figures without genitals, i.e., GI Joe, and Ken dolls. Additionally, some participants reported having: (1) witnessed animal castration (23.7%); (2) having been threatened with castration during their childhood (11.9%); (3) receiving genital injuries inflicted by others (11.0%); (4) pretending to be castrated (60.2%); (5) thinking of self-castration (54.2%); or (6) injuring their own penis (23.4%). Having received genital injuries inflicted by others was associated with attraction to males without testicles (OR = 1.997, p < .05), but not for attraction to males without a penis. Paraphilic attraction to males without genitals (i.e., castrated or penectomized) was associated with feeling attractive without genitals, having pretended to be castrated, considering self-castration, and having injured one's own penis. In conclusion, paraphilic attraction to males without genitals may be associated with traumatic early life events, body image, and desire for one's own genital ablation.

Are Autism Spectrum Disorder and Asexuality Connected?

Asexuality is a lack of sexual attraction to any gender. There is some evidence to suggest that many self-identified asexuals have a formal diagnosis of autism spectrum disorder which is characterized by deficits in social interaction and communication, as well as by restricted and repetitive interests and behaviors. Additionally, the literature shows that asexuality and lack of sexual attraction or low sexual interest is overrepresented in people with autism spectrum disorder compared with neurotypical samples. Nevertheless, no studies have been conducted to investigate the relationship between autism and asexuality in depth. We conducted a systematic review of the literature to examine whether asexuality and autism spectrum disorder are connected. We conclude that asexuality and autism share various aspects, such as a possible role of prenatal factors, reference to romantic dimensions of sexual attraction and sexual orientation, and non-partner-oriented sexual desire, but future research should explore and clarify this link.

Romantic and Sexual Relationships with Adult Partners Among Pedohebephilic Men

This study examined reasons for romantic and sexual relationships with adult partners among men with pedohebephilic preferences (N = 125). We also explored whether age sexual orientation impacted reasons for engaging in sex with adult partners. Pedohebephilic men endorsed both non-sexual and sexual reasons for engaging in adult-partnered relationships. The top reasons for sexual relationships with adult partners were pleasure, love and commitment, physical desirability, experience seeking, and practicality. The top reasons for romantic relationships with adult partners were to gain companionship, love toward romantic partner, to escape loneliness, to engage in sexual activities, and it seemed natural. The exclusivity of attraction to children was found to be significantly related to some of the factors. These findings support differential reasons for pedophilic men engaging in adult-partnered relationships. Professionals should seek to understand the nature of their clients' relationships and age sexual orientation to determine whether such factors are relevant. Professionals can then support clients in their search for meaningful relationships.

Adolescent Sexual Behavior Patterns in a British Birth Cohort: A Latent Class Analysis

This study examined adolescent sexual behaviors patterns, and the consistency between sexual behavior and sexual orientation, in a prospective birth cohort. We used data on 5150 young people from the Avon Longitudinal Study of Parents and Children. Sexual orientation was assessed using a 5-point scale of sexual attraction at 15.5 years. Fourteen sexual activities were assessed using the Adolescent Sexual Activities Index at 13.5 and 15.5 years. Latent class analysis suggested four subgroups of adolescent sexual behaviors at 13.5: a "high-intensity sexual behaviors exclusively with other-sex, no same-sex intimacy" group (3.87%); a "moderate-intensity sexual behaviors exclusively with other-sex, no same-sex intimacy" group (16.57%); a "low-intensity sexual behaviors exclusively with other-sex, no same-sex intimacy" group (34.21%); and a "no sexual behavior" group (45.35%). There were five subgroups at 15.5 where four of them (23.42%, 18.37%, 28.12%, and 24.52%, respectively) were interpreted the same as at 13.5 years and a new "high-intensity sexual behaviors, some same-sex intimacy" subgroup (5.57%). Latent transition analysis showed approximately half the adolescents moved toward greater engagement in higher intensity sexual activities with other-sex at 15.5. Boys and girls who were in groups without same-sex intimacy were predominantly attracted to the other-sex, whereas there were moderate consistencies between same-sex intimacy and same-sex attraction for boys and low consistency for girls. Findings suggest that it may be important to include low-intensity sexual behaviors when assigning adolescents to sexual orientation groupings (via sexual behaviors) in order to reduce selection biases and increase statistical power via the increase in sample size.

Why does castrated male odor attract sexually active male rats?-Attractivity induced by hypothalamus-pituitary-gonad axis block

Sexually experienced male rats show an olfactory preference for estrous female odor compared to male odor. Notably, they also prefer castrated male over gonadally intact male odor. This study examined the role of elevated circulating gonadotropins and gonadotropin-releasing hormone (GnRH) induced by disinhibition of the hypothalamus-pituitary-gonad axis in the castration-induced attractiveness of male rats. Experiment I compared preference of sexually experienced males between odors of castrated males injected with a GnRH antagonist (Cast+Ant), castrated males injected with saline (Cast), and gonadally intact males (Sham). These olfactory preference tests revealed that probe males significantly preferred Cast over Sham and Cast+Ant odors but had no preference between Sham and Cast+Ant odors. Experiment II used hypophysectomy (HPx) to remove the gonadotropin source in place of pharmacologically antagonizing GnRH. Similarly, the probe males preferred Cast (high both GnRH and gonadotropins) over HPx (high GnRH but no gonadotropin) odors, but also preferred HPx than Sham (low both GnRH and gonadotropins) odors. We then examined the effects of exogenous gonadotropins, human chorionic gonadotropin (hCG) and equine chorionic gonadotropin (eCG), to reveal which gonadotropins critically affect on the attractiveness of HPx males. The olfactory preference tests revealed that injecting eCG, but not hCG, significantly increased the probe males` preference compared to HPx male odor, suggesting that the attractiveness is augmented via follicle stimulating hormone (FSH) receptor rather than luteinizing hormone receptor. These results indicate that sexually active male rats show olfactory preference for castrated male rats due to elevated GnRH and FSH blood levels produced by a lack of androgens.

Ace and Aro: Understanding Differences in Romantic Attractions Among Persons Identifying as Asexual

First characterized by Kinsey in 1948, asexuality can be broadly defined as an absence of sexual attraction, with approximately 1% of the population identifying as asexual. While asexuality research has flourished recently, very few papers have investigated the unique mechanism of romantic attraction in asexual people, notably that some experience romantic attraction (romantic asexual) while others do not (aromantic asexual). This study compared romantic and aromantic asexual individuals through secondary data analysis on demographic, behavioral, psychological, and physiological measures as the primary objective and compared asexual people to allosexual people on some measures as a secondary aim. After combining data from seven previous asexuality studies (n = 4032 total), we found that 74.0% of asexual people reported experiencing romantic attraction. No significant difference was found in distribution of men and women between the aromantic and romantic asexual groups, though the asexual group showed higher proportions of women and non-binary genders compared to the allosexual comparison group. Romantic asexual participants reported a diverse range of romantic orientations, with only 36.0% reporting a heteroromantic orientation, compared to 76.2% of allosexual participants. As predicted, romantic asexual individuals were more likely to have been in a relationship when completing the survey, reported more past romantic and sexual partners and more frequent kissing than aromantic asexual people, and experienced more partner-oriented sexual desire than the aromantic asexual group. There were also differences in personality as romantic asexual people were less cold, more nurturant, and more intrusive than the aromantic asexual group. No difference was seen between romantic and aromantic asexual individuals in demographic characteristics, likelihood of having children, solitary sexual desire, physiological sexual functioning, frequencies of masturbation and sexual fantasy, or depression. These similarities and differences between romantic and aromantic asexual people highlight the diversity within the asexual community.

Stability versus Fluidity of Adolescent Romantic and Sexual Attraction and the Role of Religiosity: A Longitudinal Assessment in Two Independent Samples of Croatian Adolescents

The manner in which individuals report their sexual attraction, self-label their sexual identity, or behave in sexual situations can vary over time, and particularly, adolescents may change their reported sexual attraction or sexual orientation identity over the course of their development. It is important to better understand the social factors that may influence these changes, such as one's religiosity. The present study thus aimed to assess the fluidity of adolescent romantic and sexual attraction over time and to explore the role of religiosity in this dynamic using two independent panel samples of Croatian high school students (N = 849 and N = 995). Response items for sexual and romantic attraction were categorized based on the Kinsey scale, and religiosity was assessed with a standard one-item indicator. Results demonstrated that changes in attraction were substantially more prevalent among non-exclusively heterosexual participants compared to exclusively heterosexual participants in both panels. Although more female than male adolescents reported non-heterosexual attraction, gender differences in attraction fluidity were inconsistent. Religiosity was associated with initial sexual attraction (more religious individuals were more likely to report exclusively heterosexual attraction), but not with changes in romantic and sexual attraction over time. Given that the understanding of adolescent sexual development can play an important role in reducing their vulnerability to sexual risk taking, stigmatization, and abuse, this study's findings have relevance for teachers, parents, and counselors working with adolescents, and in particular for sexual minority youth.

Sexual orientation, attraction and risk for deliberate self-harm: Findings from a nationally representative sample

To date, there has been limited investigation identifying predictors of deliberate self-harm (DSH) among sexual minority adults. The present study examined the likelihood of DSH by sexual minority status as measured by self-reported sexual identity and sexual attraction in the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC). Among respondents who answered both the sexual identity and attraction items on the NESARC (N = 34,273), the link between sexual minority status and DSH was examined. Univariate analyses yielded greater risk of DSH for all sexual minority identities compared to heterosexual identity. Individuals with same-sex only attraction did not differ from those with different-sex only attraction. At the multivariate level, respondents reporting bisexual and unsure identity and bisexual attraction were at two to three times greater risk of DSH compared to their heterosexual/different-sex counterparts. Same-sex attracted and gay/lesbian individuals did not differ from different-sex attracted or heterosexual individuals in adjusted multivariate models. Findings from this nationally representative sample are consistent with previous research suggesting that sexual minority status is a risk factor for DSH. There is a vital need to incorporate varying measures of sexual minority status within research and in clinics, as well as to inquire about DSH among sexual minorities.

Understanding Alcohol and Tobacco Consumption in Asexual Samples: A Mixed-Methods Approach

Existing research suggests significant differences in alcohol and tobacco consumption trends according to one's sexual orientation. However, asexual people have not yet been included in these comparisons. In this mixed-methods, two-part study, we sought to compare group differences in alcohol and tobacco consumption among sexual orientations, focusing on asexual people, sexual people, and those in the "gray" area between asexual and sexual (i.e., "gray-asexual"). Data for Study 1 came from four British studies: National Surveys of Sexual Attitude and Lifestyles I, II, and III in 1990, 2000, and 2010 (NATSAL I, II, III) and Towards Better Sexual Health (TBSH) in 2000. Sample sizes for each study by gender are: NATSAL I-M: 1923 F: 3511; NATSAL II-M: 4604 F: 6031; NATSAL III-M: 6122 F: 7966; TBSH-M: 347 F: 552. Notably, asexual and gray-asexual respondents were found to consume significantly less alcohol and were more likely to abstain from drinking alcohol altogether, compared to allosexual respondents. Differences in tobacco consumption were only statistically significant for asexual respondents in two of three studies that included tobacco consumption. Each of the four studies also found that asexual and gray-asexual respondents were more likely to be non-drinkers (40.0-77.8%, asexual and 28.1-50.1% gray-asexual, non-drinkers, respectively) than allosexual respondents (10.2-27.2%, non-drinkers). Interviews conducted in Study 2 identified somatic, social, and psychological experiences and motivations that may shed light on the reasons for lower drinking frequencies among asexual individuals. Variability in alcohol consumption levels among asexual, lesbian, gay, and bisexual respondents, and the general population raises new questions about the motivations for why people consume alcohol.

Human voice attractiveness processing: Electrophysiological evidence

Voice attractiveness plays a significant role in social interaction and mate choice. However, how listeners perceive attractive voices and whether this process is mandatory, is poorly understood. The current study explores this question using event-related brain potentials. Participants listened to syllables spoken by male and female voices with high or low attractiveness while completing an implicit (voice un-related) tone detection task or explicitly judging voice attractiveness. In both tasks, attractive male voices elicited a larger N1 than unattractive voices. However, an effect of voice attractiveness on the late positive complex (LPC) was only seen in the explicit task but it was present to both same- and opposite-sex voices. Taken together, voice attractiveness processing during early stages appears to be rapid and mandatory and related to mate selection, whereas during later elaborated processing, voice attractiveness is strategic and aesthetics-based, requiring attentional resources.

Effects of Individual Difference Variables, Gender, and Exclusivity of Sexual Attraction on Volunteer Bias in Sexuality Research

Sexuality research is often regarded as more intrusive than other types of research, contributing to sample self-selection biases. Researchers have consistently found that volunteers and non-volunteers for sexuality studies differ on a number of sexuality-related variables. Despite a large number of studies examining volunteer biases, relatively few have examined the effects of gender and exclusivity of sexual attraction on willingness to volunteer. Given that comparisons on the basis of gender and/or sexual attraction are frequently made in sexuality studies, understanding how these factors may contribute to volunteer bias is particularly important. In the current study, we investigated the impact of gender and sexual attraction, as well as individual difference variables, on hypothetical willingness to volunteer for a variety of sexuality studies, including new measurement technologies not previously investigated. Greater proportions of men and individuals with any degree of same-gender attraction reported that they were willing to volunteer for eye tracking and psychophysiology studies, whereas there were no significant effects of gender or sexual attraction on willingness to volunteer for sexuality surveys. The proportions of volunteers willing to participate were inversely related to study invasiveness. Greater sexual experience and more positive sexual attitudes were significant predictors of willingness to volunteer, whereas gender, sexual attraction, and other sexuality characteristics were not significant predictors. Implications of volunteer bias for research findings are discussed. Strategies to minimize volunteer bias and to examine whether or not recruited samples differ from the population are provided.

Relationships Among Sexual Identity, Sexual Attraction, and Sexual Behavior: Results from a Nationally Representative Probability Sample of Adults in the United States

Sexual orientation is a multi-dimensional concept, at a minimum comprised of sexual identity, sexual attraction, and sexual behavior. Our study aimed to assess relationships among self-identified sexual identity, sexual attraction, and sexual behaviors in a probability sample of adults in the U.S. and to identify associated factors with diverse patterns. We collected data from adults in the 2015 National Survey of Sexual Health and Behavior, an Internet-based nationally representative probability survey of the general U.S. population. Concordance between sexual identity versus sexual attraction and sexual behaviors was assessed using percent agreement. We identified correlates of discordance using logistic regression. Concordance between sexual identity versus sexual attraction and past-year sexual behaviors was 94% and 96%, respectively, though our sample was predominately composed of heterosexual individuals. Women and sexual minority individuals reported greater discordance across sexuality-related measures than men and heterosexual individuals. Younger adults (aged 18-24 years) were more likely to report sexual behaviors discordant with sexual identity compared with older adults (including those ages 25-34 years). Higher levels of educational attainment were significantly associated with less discordance of reported recent sexual activity and sexual identity. Measures of sexual identity, attraction, and behaviors are not interchangeable. Future research should consider multiple sexuality-related measures in order to capture the complexity and variability of sexualities.

Sexual Attraction, Sexual Identity, and Same-Sex Sexual Experiences of Adult Offspring in the U.S. National Longitudinal Lesbian Family Study

The U.S. National Longitudinal Lesbian Family Study has followed offspring with sexual minority parents from conception into adulthood. It was initiated in 1986, and it has a 92% retention rate to date. In the current investigation, the 25-year-old offspring answered questions about sexual attraction, sexual identity, and sexual experiences; their responses were compared with those of same-age adults from a population-based survey. The analytic samples consisted of 76 offspring of lesbian parents and 76 demographically matched participants from the National Survey of Family Growth. All 152 respondents were 25 years old, 48.7% were female, 90.8% identified as White, 9.2% were people of color, and all had attended at least some college. Although most respondents in each sample identified as "heterosexual or straight," compared to their matched counterparts in the population-based survey, the female and male offspring of lesbian parents were significantly more to likely to report same-sex attraction, sexual minority identity, and same-sex experience. These findings suggest that adult offspring from planned lesbian families may be more likely than their peers to demonstrate diversity in sexual attraction, identity, and expression.

Dual roles of anterior cingulate cortex neurons in pain and pleasure in adult mice

Human and animal studies indicate that some brain regions are activated during painful and pleasant situations, such as the anterior cingulate cortex (ACC). In the present study, we wanted to determine if some of the same neurons in the ACC may be activated by both pain and pleasure. We labeled neurons activated by two stimuli by using two immediate early genes (IEGs), Arc and Homer1a, and detected the intranuclear transcription of the IEG mRNA in situ. We found that there are double-labeling neurons in the ACC after the mice received pain and sexual attraction stimulation. The double-labeling ACC neurons were higher in male mice exposed to female mice (attractive stimulus) than the group exposed to male mice (normal stimulus). The IEG, which indicates the sexual attraction, were also higher in the female exposing group, while the IEG indicating pain showed no significant variance between two groups. Our findings suggest that ACC neurons play important roles in the process of both pain and pleasure.

Patterns of Asexuality in China: Sexual Activity, Sexual and Romantic Attraction, and Sexual Desire

This study examined patterns of asexuality in Chinese asexual people in terms of sexual activities, sexual/romantic attraction, and sexual desire. The sample included 227 (64 men and 163 women) asexual participants and 57 (26 men and 31 women) uncertain asexual participants recruited from social networks for asexual people. The control group included 217 (115 men and 102 women) heterosexual participants recruited from general social networks. Participants scoring 40 or higher on the Asexuality Identification Scale were classified as asexual. Asexual participants reported having less frequent masturbation, sexual intercourse experience, and sexual and romantic attraction compared to heterosexual participants. Lower sexual attraction among asexuals indicated that "people who experience little or no sexual attraction" would be a more appropriate definition of asexuality. The pattern of uncertain asexual participants' sexual/romantic attraction and sexual desire was intermediate between heterosexual and asexual participants. Asexual participants scored significantly lower on dyadic sexual desire and slightly lower on solitary sexual desire than heterosexual participants. There were significant differences in sexual activities and solitary sexual desire among romantic orientation categories. Homoromantic participants showed higher dyadic sexual desire and were more likely to engage in masturbation, indicating the heterogeneity among asexual people. The findings indicated that Chinese asexual people showed similar patterns of asexuality as in Western nations. Specifically, asexual people have little or no sexual attraction, non-partner-orientated sexual desire, and are heterogeneous in sexual activities and sexual desire. This implies similar mechanisms underlying the etiology of asexuality across cultures.

Sexual attraction and the nonmedical use of opioids and sedative drugs among Chinese adolescents

OBJECTIVE

The nonmedical use of prescription drugs (NMUPD) is attracting public attention. We aimed to explore the association between sexual attraction and NMUPD among Chinese adolescents.

METHOD

A school-based survey was conducted in seven Chinese provinces, and a multi-stage stratified cluster sampling method was used in this study. A total of 150,822 students from seven Chinese provinces completed the questionnaire; the response rate was 95.93%. All data were collected between November 2014 and January 2015.

RESULTS

Overall, 8.8%, 4.4%, and 2.2% of the students reported lifetime, past-year, and past-month NMUPD, respectively. Compared with heterosexual students (8.2%), sexual minority and unsure students were more likely to report lifetime NMUPD (14.4% and 10.0%, respectively; χ² = 244.34, P < 0.001). In addition, sexual minority and unsure students were more likely to admit past-year and past-month use of NMUPD. After adjusting for social demographics and lifestyle covariates, sexual minority and unsure students were at an increased risk of lifetime NMUPD (adjusted odds ratio [AOR] = 1.68, 95% confidence interval [CI] = 1.54-1.83 and AOR = 1.33, 95% CI = 1.26-1.41, respectively).

CONCLUSIONS

Our study suggested that sexual minority and unsure adolescents have a higher risk of NMUPD. Moreover, our study suggested that sexual minority and unsure students are more likely to both try and continue to use prescription drugs. Further studies focusing on the mechanism of substance abuse and appropriate interventions among sexual minority and unsure adolescents are warranted.

Interviewing Adolescents About Sexual Matters

To optimally address sex and sexuality, normalize gender and sexual diversities, and attend to adolescents' needs, clinicians will best serve their patients and their families by becoming comfortable initiating confidential, developmentally appropriate discussions with all adolescent patients. The goal is to create a safe, affirming, nonjudgmental space wherein adolescents may learn about sexual matters, discuss concerns, ask questions, and find support to assist them to achieve healthy, positive development. This article provides useful, practical suggestions to begin these conversations, offers specific examples and tips to encourage dialogue, and discusses ways to be a resource to adolescent patients.

Sociosexuality, Commitment, and Sexual Desire for an Attractive Person

Sociosexuality refers to a personal predisposition to engage in uncommitted sex. Romantically involved individuals are more likely to engage in infidelity when more unrestricted in their sociosexuality and less committed to their current partners. However, commitment reliably predicts relationship maintenance and the activation of pro-relationship behaviors, regardless of sociosexuality levels. In two studies (Study 1: N = 566 heterosexuals; M _age = 21.24, SD = 4.45; Study 2: N = 168 heterosexuals; M _age = 23.28, SD = 5.60), the association between sociosexuality and commitment was examined. Replicating previous findings, men were more sociosexually unrestricted than women, and single individuals were more sociosexually unrestricted than their romantically involved counterparts (Study 1). Results also showed that more committed individuals were more restricted in their sociosexuality (Studies 1 and 2) and that commitment was negatively associated with physical and sexual attraction to an attractive person, regardless of sociosexuality levels (Study 2). Furthermore, commitment, but not sociosexuality, predicted sexual infidelity in the current relationship and this effect emerged even among sociosexually unrestricted individuals (Studies 1 and 2). No additional gender differences were found across studies. These results converge with findings suggesting that individuals shift their mating strategies and restrict their sociosexuality when in a romantic relationship and that commitment prevents relationship threatening behaviors such as sexual attraction or sexual infidelity.

Heterosexual Men's Ratings of Sexual Attractiveness of Adolescent Girls: A Cross-Cultural Analysis

Following an identical procedure to the one we previously reported (O'Donnell, Lowe, Brotherton, & Bennett, 2014), we examined ratings of sexual attraction to photographs of (the same) adolescent girls (Tanner stages 3-4) labelled as either 14-15 years or 16-17 years old, women, and men. Ratings were made by Bulgarian heterosexual men by pressing buttons on a response box which recorded the ratings made and the time in milliseconds taken to respond. Despite the age of sexual consent in Bulgaria being 14 years, the pattern of findings did not differ from those found in the UK, where the age of consent is 16 years. That is, mean ratings of the sexual attractiveness of the girls labelled as younger were lower than those of the (same) girls labelled as older, and those of the women. In addition, correlations revealed significantly longer responding times when younger girls (and men) were rated as more highly sexually attractive. These associations were reversed in response to the photographs of women. We take these findings to indicate an inhibitory effect arising from generalized sexual norms relating to the inappropriateness of sexual attraction to young girls; the greater the attraction, the higher the inhibition. This second replication of our initial findings suggests a robust effect that may be of benefit in exploration of pedophile or sex offender groups.

PSA-NCAM in the posterodorsal medial amygdala is necessary for the pubertal emergence of attraction to female odors in male hamsters

During puberty, attention turns away from same-sex socialization to focus on the opposite sex. How the brain mediates this change in perception and motivation is unknown. Polysialylated neural cell adhesion molecule (PSA-NCAM) virtually disappears from most of the central nervous system after embryogenesis, but it remains elevated in discrete regions of the adult brain. One such brain area is the posterodorsal subnucleus of the medial amygdala (MePD). The MePD has been implicated in male sexual attraction, measured here as the preference to investigate female odors. We hypothesize that PSA-NCAM gates hormone-dependent plasticity necessary for the emergence of males' attraction to females. To evaluate this idea, we first measured PSA-NCAM levels across puberty in several brain regions, and identified when female odor preference normally emerges in male Syrian hamsters. We found that MePD PSA-NCAM staining peaks shortly before the surge of pubertal androgen and the emergence of preference. To test the necessity of PSA-NCAM for female odor preference, we infused endo-neuraminidase-N into the MePD to deplete it of PSAs before female odor preference normally appears. This blocked female odor preference, which suggests that PSA-NCAM facilitates behaviorally relevant, hormone-driven plasticity.

Peripubertal exposure to male odors influences female puberty and adult expression of male-directed odor preference in mice

Testosterone-dependent olfactory signals emitted by male are well known to accelerate female puberty in mice (Vandenbergh effect). However, it remains unclear whether these chemosignals also influence adult expression of male-directed odor preference. Therefore, we exposed female mice to intact or castrated male bedding (vs clean bedding as control) during the peripubertal period (postnatal day (PD) 21-38) and measured male-directed odor preference in adulthood. At PD45 or PD60, females exposed to intact male odors, and thus showing puberty acceleration, preferred to investigate odors from intact males over females or castrated males. Females exposed to castrated male odors did not show puberty acceleration but preferred male (intact or castrated) over female odors. Finally, control females did not show any odor preference when tested at PD45, although a preference for male odors emerged later (PD60). In a second experiment, females that were exposed to intact male odors after pubertal transition (PD36-53) also preferred intact male over castrated male odors. In conclusion, our results indicate that peripubertal exposure to male odors induced early expression of male-directed odor preference regardless of puberty-accelerating effect and that induction of male-directed odor preference is not specific to the peripubertal period.

Focal lesions within the ventral striato-pallidum abolish attraction for male chemosignals in female mice

In rodents, socio-sexual behaviour is largely mediated by chemosensory cues, some of which are rewarding stimuli. Female mice display an innate attraction towards male chemosignals, dependent on the vomeronasal system. This behaviour likely reflects the hedonic value of sexual chemosignals. The anteromedial aspect of the olfactory tubercle, along with its associated islands of Calleja, receives vomeronasal inputs and sexually-dimorphic vasopressinergic innervation. Thus, we hypothesised that this portion of the ventral striato-pallidum, known to be involved in reward processing, might be important for sexual odorant-guided behaviours. In this study, we demonstrate that lesions of this region, but not of regions in the posterolateral striato-pallidum, abolish the attraction of female mice for male chemosignals, without affecting significantly their preference for a different natural reward (a sucrose solution). These results show that, at least in female mice, the integrity of the anterior aspect of the medioventral striato-pallidum, comprising a portion of the olfactory tubercle and associated islands of Calleja, is necessary for the attraction for male chemosignals. We suggest that this region contributes to the processing of the hedonic properties of biologically significant odorants.

The gender you are and the gender you like: sexual preference and empathic neural responses

BACKGROUND

Empathy relates to the ability to share the emotions and understand the intentions and emotions of the other. Although it has been suggested that women have superior empathic abilities as compared to men, it is unknown whether it is the gender or the sexual preference of the individual that affects empathy. Given that sexual attraction has been reported to affect social behavior, the present study explored the possibility that sexual orientation affects behavioral measures of empathy as well as empathy related activations.

METHODS

Fifty two heterosexual and homosexual women and men were scanned while performing an emotional judgment task involving emotional understanding of a protagonist.

RESULTS

The behavioral and neuroimaging results indicate that empathy is related to the gender as well as the sexual preference of the participant. Individuals sexually attracted to men (heterosexual women and homosexual men) showed greater empathy than subjects attracted to women (heterosexual men and homosexual women). Furthermore, brain imaging data reveal that regions within the temporo-parietal junction (TPJ), showed sensitivity to the sexual orientation of the individual, such that it was activated more in subjects attracted to men than in subjects attracted to women while evaluating the emotional state of the other. Moreover, the activation in the TPJ was found to be correlated with the degree to which subjects were empathizing.

CONCLUSIONS

These results suggest that individual differences in empathy are related to the gender as well as the sexual orientation of the subject.