Considering the role of conditioning in sexual orientation

The New Genetic Evidence on Same-Gender Sexuality: Implications for Sexual Fluidity and Multiple Forms of Sexual Diversity

In September of 2019, the largest-ever (N = 477,522) genome-wide-association study of same-gender sexuality was published in Science. The primary finding was that multiple genes are significantly associated with ever engaging in same-gender sexual behavior, accounting for between 8-25% of variance in this outcome. Yet an additional finding of this study, which received less attention, has more potential to transform our current understanding of same-gender sexuality: Specifically, the genes associated with ever engaging in same-gender sexual behavior differed from the genes associated with one's relative proportion of same-gender to other-gender behavior. I review recent research on sexual orientation and sexual fluidity to illustrate how these findings speak to longstanding questions regarding distinctions among subtypes of same-gender sexuality (such as mostly-heterosexuality, bisexuality, and exclusive same-gender experience). I conclude by outlining directions for future research on the multiple causes and correlates of same-gender expression.

Foundations of Erobotics

Technology is giving rise to artificial erotic agents, which we call erobots (erôs + bot). Erobots, such as virtual or augmented partners, erotic chatbots, and sex robots, increasingly expose humans to the possibility of intimacy and sexuality with artificial agents. Their advent has sparked academic and public debates: some denounce their risks (e.g., promotion of harmful sociosexual norms), while others defend their potential benefits (e.g., health, education, and research applications). Yet, the scientific study of human-machine erotic interaction is limited; no comprehensive theoretical models have been proposed and the empirical literature remains scarce. The current research programs investigating erotic technologies tend to focus on the risks and benefits of erobots, rather than providing solutions to resolve the former and enhance the latter. Moreover, we feel that these programs underestimate how humans and machines unpredictably interact and co-evolve, as well as the influence of sociocultural processes on technological development and meaning attribution. To comprehensively explore human-machine erotic interaction and co-evolution, we argue that we need a new unified transdisciplinary field of research-grounded in sexuality and technology positive frameworks-focusing on human-erobot interaction and co-evolution as well as guiding the development of beneficial erotic machines. We call this field Erobotics. As a first contribution to this new discipline, this article defines Erobotics and its related concepts; proposes a model of human-erobot interaction and co-evolution; and suggests a path to design beneficial erotic machines that could mitigate risks and enhance human well-being.

Sex differences in behavior and neuropharmacology of zebrafish

Sex is an important variable in biomedical research. The zebrafish (Danio rerio) is increasingly utilized as a powerful new model organism in translational neuroscience and pharmacology. Mounting evidence indicates important sex differences in zebrafish behavioral and neuropharmacological responses. Here, we discuss the role of sex in zebrafish central nervous system (CNS) models, their molecular mechanisms, recent findings and the existing challenges in this field. We also emphasize the growing utility of zebrafish models in translational neuropharmacological research of sex differences, fostering future CNS drug discovery and the search for novel sex-specific therapies. Finally, we highlight the interplay between sex and environment in zebrafish models of sex-environment correlations as an important strategy of CNS disease modeling using this aquatic organism.

Can music cue sexual arousal?

The preparation hypothesis posits that women's genital responses (vasocongestion and lubrication) occur automatically in the presence of any sexual stimulus to prevent injuries from sexual activities. It follows that women's genital responses should be easily conditioned to non-sexual cues that reliably predict impending sexual activities. It has been difficult, however, to demonstrate classical conditioning of genital responses in women in the laboratory. In the current study, we used music as an auditory conditioned stimulus (CS) and vignette narrations of consensual sex, non-consensual sex, and neutral (nonsexual) interactions as unconditioned stimuli (US). Eighteen women (range=18–27 years, M=21.9 years, SD=2.2 years,) and 18 men (range=19–29 years, M=22.8 years, SD=2.8 years) were exposed to three neutrally-rated classical music pieces, each paired with a different type of vignette. Participants were exposed to 3 pre-acquisition trials, 12 acquisition trials, and a minimum of 9 extinction trials. After each trial, participants were asked to rate the CS (or the US in CS-US pairings) on pleasantness, anxiousness, and perceived sexual arousal. Vaginal photoplethysmography and penile plethysmography were used to assess changes in genital responses. The sexual vignettes produced genital responses and the nonsexual vignettes did not. We did not observe conditioning of genital responses to music in either sex, but did so for men's and women's feelings of sexual arousal toward songs paired with a consensual sex story. The results were not consistent with the preparation hypothesis.

Etiological Risk Factors for Sibling Incest: Data From an Anonymous Computer-Assisted Self-Interview

Retrospective data from 1,821 women and 1,064 men with one or more siblings, provided anonymously using a computer-assisted self-interview, were used to identify risk factors for sibling incest (SI); 137 were participants in SI. In order of decreasing predictive power, the risk factors identified by the multiple logistic regression analysis included ever having shared a bed for sleeping with a sibling, parent-child incest (PCI), family nudity, low levels of maternal affection, and ever having shared a tub bath with a sibling. The results were consistent with the idea that SI in many families was the cumulative result of four types of parental behaviors: (a) factors that lower external barriers to sexual behavior (e.g., permitting co-sleeping or co-bathing of sibling dyads), (b) factors that encourage nudity of children within the nuclear family and permit children to see the parent's genitals, (c) factors that lead to the siblings relying on one another for affection (e.g., diminished maternal affection), and (d) factors that eroticize young children (e.g., child sexual abuse [CSA] by a parent). Thirty-eight of the 137 SI participants were participants in coerced sibling incest (CSI). In order of decreasing predictive power, risk factors for CSI identified by multiple logistic regression analysis included ever having shared a bed for sleeping with a brother, PCI, witnessing parental physical fighting, and family nudity. SI was more likely to have been reported as CSI if the sibling had touched the reporting sibling's genitals, and less likely to have been reported as CSI if the siblings had shared a bed.

Psychological and physical health of mostly heterosexuals: a systematic review

We reviewed whether mostly heterosexuals, a sexual orientation group characterized by a small amount of same-sex sexuality, differ from heterosexuals and bisexuals on a variety of mental and physical health outcomes (e.g., internalizing problems, body dissatisfaction and disordered eating, obesity, sexual/reproductive health, physical health), health risk behaviors (e.g., substance use, sexual risk taking), and risk and protective factors (e.g., victimization, stressful/risky environment, socioeconomic status, personal and social relationships, gender nonconformity). A narrative and quantitative literature review was conducted of 60 papers covering 22 samples from five Western countries. Individual, mean, and median effect sizes (Cohen ds) were calculated whenever possible. Mostly heterosexuals reported higher levels of risk in most reviewed outcomes compared to heterosexuals (unweighted mean effect sizes ranged from 0.20 to 0.50) but typically somewhat lower than bisexuals (unweighted mean effect sizes ranged from -0.10 to -0.30). Various risk factors frequently reduced, but rarely eliminated, health disparities between mostly heterosexuals and heterosexuals. Findings are discussed through the lens of three potential explanations of elevated health risks among nonheterosexuals: minority stress, nonheterosexual lifestyles, and common causes. Because data on many outcomes were scarce or missing, particularly for men and in comparison with bisexuals, further research is needed.

Who, what, where, when (and maybe even why)? How the experience of sexual reward connects sexual desire, preference, and performance

Although sexual behavior is controlled by hormonal and neurochemical actions in the brain, sexual experience induces a degree of plasticity that allows animals to form instrumental and Pavlovian associations that predict sexual outcomes, thereby directing the strength of sexual responding. This review describes how experience with sexual reward strengthens the development of sexual behavior and induces sexually-conditioned place and partner preferences in rats. In both male and female rats, early sexual experience with partners scented with a neutral or even noxious odor induces a preference for scented partners in subsequent choice tests. Those preferences can also be induced by injections of morphine or oxytocin paired with a male rat's first exposure to scented females, indicating that pharmacological activation of opioid or oxytocin receptors can "stand in" for the sexual reward-related neurochemical processes normally activated by sexual stimulation. Conversely, conditioned place or partner preferences can be blocked by the opioid receptor antagonist naloxone. A somatosensory cue (a rodent jacket) paired with sexual reward comes to elicit sexual arousal in male rats, such that paired rats with the jacket off show dramatic copulatory deficits. We propose that endogenous opioid activation forms the basis of sexual reward, which also sensitizes hypothalamic and mesolimbic dopamine systems in the presence of cues that predict sexual reward. Those systems act to focus attention on, and activate goal-directed behavior toward, reward-related stimuli. Thus, a critical period exists during an individual's early sexual experience that creates a "love map" or Gestalt of features, movements, feelings, and interpersonal interactions associated with sexual reward.