Neuroimaging of Female Sexual Desire and Hypoactive Sexual Desire Disorder

The Neuroendocrine Regulation of Reproductive Behavior and Emotional Control by Kisspeptin

Reproductive success and ultimately species survival at a population level is contingent on a plethora of neuroendocrine signals working in concert to regulate gonadal function and reproductive behavior. Among these, the neuropeptide kisspeptin (encoded by the KISS1/Kiss1 gene) has emerged as the master regulator of the hypothalamic-pituitary-gonadal axis. Besides the hypothalamus, both kisspeptin and its cognate receptor are extensively expressed throughout cortico-limbic brain structures in rodents and humans, which are regions traditionally implicated in behavioral and emotional responses. Thus, there exists a neuroanatomical framework through which kisspeptin can integrate reproductive behavior and emotional regulation with the reproductive axis. Accordingly, this sets the scene for recent findings derived from an assortment of species, including humans, unveiling kisspeptin as an important gatekeeper of reproductive behavior and emotional control. Herein, we summarize the major preclinical animal and human experimental evidence identifying kisspeptin as a key neuromodulator of reproductive behavior and emotional state. Such findings have laid the foundations for clinical applications of kisspeptin-based therapies for patients with related reproductive and psychosexual disorders.

Topological abnormalities of left middle orbital frontal gyrus and amygdala associated with hypoactive sexual desire disorder: A diffusion tensor imaging study

INTRODUCTION

Sexual desire has been found to be associated with brain areas involved in sexual excitation and inhibition. However, little is known regarding whether hypoactive sexual desire disorder patients have structural abnormalities related to hypofunctional excitation or hyperfunctional inhibition in the brain.

METHODS

Magnetic resonance imaging data were collected from 26 hypoactive sexual desire disorder patients and 28 healthy controls. The structural brain networks were constructed based on diffusion tensor imaging data. Finally, the nodal parameters were calculated by the graph theoretical analysis and were compared between hypoactive sexual desire disorder and healthy controls.

RESULTS

There were no significant differences in the age, education level, and scores of emotional scales between groups. Meanwhile, all hypoactive sexual desire disorder patients showed normal hormone levels. Compared with healthy controls, hypoactive sexual desire disorder patients showed higher scores on the Arizona Sexual Experience Scale and its sexual desire subscale. In fractional anisotropy-weighted brain networks, a decreased clustering coefficient was found in the left middle frontal gyrus (orbital part), and decreased local efficiency was found in the left amygdala of hypoactive sexual desire disorder patients when compared with healthy controls.

CONCLUSION

The present study demonstrated impaired left middle orbital frontal gyrus and amygdala in the structural brain network of hypoactive sexual desire disorder patients, which might be the central pathological mechanisms underlying hypoactive sexual desire disorder and could be used as a neuroimaging diagnostic biomarker for hypoactive sexual desire disorder.

Kisspeptin and neurokinin B: roles in reproductive health

Kisspeptin and neurokinin B (NKB) play a key role in several physiological processes including in puberty, adult reproductive function including the menstrual cycle, as well as mediating the symptoms of menopause. Infundibular kisspeptin neurons, which coexpress NKB, regulate the activity of gonadotropin-releasing hormone (GnRH) neurons and thus the physiological pulsatile secretion of GnRH from the hypothalamus. Outside of their hypothalamic reproductive roles, these peptides are implicated in several physiological functions including sexual behavior and attraction, placental function, and bone health. Over the last two decades, research findings have considerably enhanced our understanding of the physiological regulation of the hypothalamic-pituitary-gonadal (HPG) axis and identified potential therapeutic applications. For example, recognition of the role of kisspeptin as the natural inductor of ovulation has led to research investigating its use as a safer, more physiological trigger of oocyte maturation in in vitro fertilization (IVF) treatment. Moreover, the key role of NKB in the pathophysiology of menopausal hot flashes has led to the development of pharmacological antagonism of this pathway. Indeed, fezolinetant, a neurokinin 3 receptor antagonist, has recently received Food and Drug Administration (FDA) approval for clinical use to treat menopausal vasomotor symptoms. Here, we discuss the roles of kisspeptin and NKB in human physiology, including in the regulation of puberty, menstrual cyclicity, reproductive behavior, pregnancy, menopause, and bone homeostasis. We describe how perturbations of these key physiological processes can result in disease states and consider how kisspeptin and NKB could be exploited diagnostically as well as therapeutically to treat reproductive disorders.

Sexual Desire and Pharmacologic Management

Female sexual desire is a complex interplay of neurotransmitters and hormones. Diagnosis is based on clinical features and sexual distress. Treatments that affect neurotransmitters and hormones that may be out of balance can help improve sexual desire in women with hypoactive sexual desire disorder.

Women and men with distressing low sexual desire exhibit sexually dimorphic brain processing

Distressing low sexual desire, termed Hypoactive Sexual Desire Disorder (HSDD), affects approximately 10% of women and 8% of men. In women, the 'top-down' theory of HSDD describes hyperactivity in higher-level cognitive brain regions, suppressing lower-level emotional/sexual brain areas. However, it is unknown how this neurofunctional disturbance compares to HSDD in men. To investigate this, we employed task-based functional MRI in 32 women and 32 men with HSDD to measure sexual-brain processing during sexual versus non-sexual videos, as well as psychometric questionnaires to assess sexual desire/arousal. We demonstrate that women had greater activation in higher-level and lower-level brain regions, compared to men. Indeed, women who had greater hypothalamic activation in response to sexual videos, reported higher psychometric scores in the evaluative (r = 0.55, P = 0.001), motivational (r = 0.56, P = 0.003), and physiological (r = 0.57, P = 0.0006) domains of sexual desire and arousal after watching the sexual videos in the scanner. By contrast, no similar correlations were observed in men. Taken together, this is the first direct comparison of the neural correlates of distressing low sexual desire between women and men. The data supports the 'top-down' theory of HSDD in women, whereas in men HSDD appears to be associated with different neurofunctional processes.

Small Effects, Questionable Outcomes: Bremelanotide for Hypoactive Sexual Desire Disorder

Efficacy outcomes are only informative to the extent that they are validated. We examined the measurement properties of efficacy measures from the phase III ("RECONNECT") bremelanotide trials for hypoactive sexual desire disorder (HSDD) in women. Continuous efficacy outcomes, including a) the Female Sexual Function Index (FSFI) and its Desire domain (FSFI-D) and b) the Female Sexual Distress Scale-Desire/Arousal/Orgasm (FSDS-DAO) and its item assessing distress due to low desire (FSDS-DAO #13) have questionable, at best, validity evidence for women with HSDD. We found no validity evidence for previously published categorical treatment response outcomes from the RECONNECT trials. All efficacy results should be reported, but results on 8 of the 11 clinicaltrials.gov-specified efficacy outcomes were heretofore unpublished (including FSDS-DAO total score, FSFI total score, FSFI arousal domain, and items from the Female Sexual Encounter Profile-Revised). We analyzed these outcomes, upon which effect sizes ranged from nil to small. Several other continuous and categorical outcomes generated modest apparent benefits, though nearly all of these outcomes were likely derived post-hoc. Across RECONNECT trial data from two prior publications and the current study, bremelanotide's benefits are statistically modest and limited to outcomes for which scant evidence of validity among women with HSDD exists.

Psychedelics and sexual functioning: a mixed-methods study

Do psychedelics affect sexual functioning postacutely? Anecdotal and qualitative evidence suggests they do, but this has never been formally tested. While sexual functioning and satisfaction are generally regarded as an important aspect of human wellbeing, sexual dysfunction is a common symptom of mental health disorders. It is also a common side effect of selective serotonin reuptake inhibitors (SSRIs), a first line treatment for depression. The aim of the present paper was to investigate the post-acute effects of psychedelics on self-reported sexual functioning, combining data from two independent studies, one large and naturalistic and the other a smaller but controlled clinical trial. Naturalistic use of psychedelics was associated with improvements in several facets of sexual functioning and satisfaction, including improved pleasure and communication during sex, satisfaction with one's partner and physical appearance. Convergent results were found in a controlled trial of psilocybin therapy versus an SSRI, escitalopram, for depression. In this trial, patients treated with psilocybin reported positive changes in sexual functioning after treatment, while patients treated with escitalopram did not. Despite focusing on different populations and settings, this is the first research study to quantitively investigate the effects of psychedelics on sexual functioning. Results imply a potential positive effect on post-acute sexual functioning and highlight the need for more research on this.

The Emerging Therapeutic Potential of Kisspeptin and Neurokinin B

Kisspeptin (KP) and neurokinin B (NKB) are neuropeptides that govern the reproductive endocrine axis through regulating hypothalamic gonadotropin-releasing hormone (GnRH) neuronal activity and pulsatile GnRH secretion. Their critical role in reproductive health was first identified after inactivating variants in genes encoding for KP or NKB signaling were shown to result in congenital hypogonadotropic hypogonadism and a failure of pubertal development. Over the past 2 decades since their discovery, a wealth of evidence from both basic and translational research has laid the foundation for potential therapeutic applications. Beyond KP's function in the hypothalamus, it is also expressed in the placenta, liver, pancreas, adipose tissue, bone, and limbic regions, giving rise to several avenues of research for use in the diagnosis and treatment of pregnancy, metabolic, liver, bone, and behavioral disorders. The role played by NKB in stimulating the hypothalamic thermoregulatory center to mediate menopausal hot flashes has led to the development of medications that antagonize its action as a novel nonsteroidal therapeutic agent for this indication. Furthermore, the ability of NKB antagonism to partially suppress (but not abolish) the reproductive endocrine axis has supported its potential use for the treatment of various reproductive disorders including polycystic ovary syndrome, uterine fibroids, and endometriosis. This review will provide a comprehensive up-to-date overview of the preclinical and clinical data that have paved the way for the development of diagnostic and therapeutic applications of KP and NKB.

When the brain turns on with sexual desire: fMRI findings, issues, and future directions

INTRODUCTION

More than 2 decades of neuroimaging research has sought to uncover the neurologic basis of sexual desire. However, the lack of a clear conceptual distinction between sexual desire and sexual arousal or even a broadly accepted definition of sexual desire has led to confusion in the literature regarding brain areas uniquely associated with sexual desire.

OBJECTIVES

(1) To critically review the neuroimaging literature that seeks to identify brain areas and networks involved in sexual desire; (2) to identify and discuss those brain areas and potential networks that are most promising for providing insights to sexual desire; and (3) to offer recommendations for future studies.

METHODS

Existing meta-analyses were used as a starting point to identify relevant neuroimaging studies on sexual desire, arousal, and love. This base was then expanded via Google Scholar and forward citation tracking of already identified studies.

RESULTS

Brain areas that are commonly associated with sexual desire and arousal include the amygdala, hypothalamus, dorsal and ventral striatum, anterior cingulate, insula, and prefrontal and orbitofrontal cortex. However, because the same basic paradigm has been used to study sexual desire and arousal, unambiguous conclusions regarding areas uniquely involved in sexual desire cannot be drawn. Moreover, the lack of connectivity analyses and a failure to acknowledge negative BOLD (blood-oxygen level dependent) significantly limit conclusions on the neural basis of sexual desire.

CONCLUSION

Five recommendations are made. First, stimulus types (ie, erotic vs sexually explicit) should be selected by the meaningful theoretical conceptualization of the constructs of interest. Second, participants should be provided with definitions of sexual desire, mental sexual arousal, and perceived genital sexual arousal, so they can choose which terms best describe their experience. Third, event-related designs should be used with caution when investigating sexual desire. Fourth, time series analyses should be used to identify both positive and negative BOLD. Fifth, connectivity analyses should be performed to identify brain networks.

Effects of Kisspeptin on Sexual Brain Processing and Penile Tumescence in Men With Hypoactive Sexual Desire Disorder: A Randomized Clinical Trial

IMPORTANCE

The human physiological sexual response is crucial for reward, satisfaction, and reproduction. Disruption of the associated neurophysiological pathways predisposes to low sexual desire; the most prevalent psychological form is hypoactive sexual desire disorder (HSDD), which affects 8% of men but currently has no effective pharmacological treatment options. The reproductive neuropeptide kisspeptin offers a putative therapeutic target, owing to emerging understanding of its role in reproductive behavior.

OBJECTIVE

To determine the physiological, behavioral, neural, and hormonal effects of kisspeptin administration in men with HSDD.

DESIGN, SETTING, AND PARTICIPANTS

This double-blind, 2-way crossover, placebo-controlled randomized clinical trial was performed at a single academic research center in the UK. Eligible participants were right-handed heterosexual men with HSDD. Physiological, behavioral, functional magnetic resonance imaging (fMRI), and hormonal analyses were used to investigate the clinical and mechanistic effects of kisspeptin administration in response to visual sexual stimuli (short and long video tasks). The trial was conducted between January 11 and September 15, 2021, and data analysis was performed between October and November 2021.

INTERVENTIONS

Participants attended 2 study visits at least 7 days apart, in balanced random order, for intravenous infusion of kisspeptin-54 (1 nmol/kg/h) for 75 minutes or for administration of a rate-matched placebo.

MAIN OUTCOMES AND MEASURES

Changes in (1) brain activity on whole-brain analysis, as determined by fMRI blood oxygen level-dependent activity in response to visual sexual stimuli during kisspeptin administration compared with placebo, (2) physiological sexual arousal (penile tumescence), and (3) behavioral measures of sexual desire and arousal.

RESULTS

Of the 37 men randomized, 32 completed the trial. Participants had a mean (SD) age of 37.9 (8.6) years and a mean (SD) body mass index of 24.9 (5.4). On viewing sexual videos, kisspeptin significantly modulated brain activity in key structures of the sexual-processing network on whole-brain analysis compared with placebo (mean absolute change [Cohen d] = 0.81 [95% CI, 0.41-1.21]; P =  .003). Furthermore, improvements in several secondary analyses were observed, including significant increases in penile tumescence in response to sexual stimuli (by up to 56% more than placebo; mean difference = 0.28 units [95% CI, 0.04-0.52 units]; P = .02) and behavioral measures of sexual desire-most notably, increased happiness about sex (mean difference = 0.63 points [95% CI, 0.10-1.15 points]; P = .02).

CONCLUSIONS AND RELEVANCE

Collectively, this randomized clinical trial provides the first evidence to date showing that kisspeptin administration substantially modulates sexual brain processing in men with HSDD, with associated increases in penile tumescence and behavioral measures of sexual desire and arousal. These data suggest that kisspeptin has potential as the first pharmacological treatment for men with low sexual desire.

TRIAL REGISTRATION

isrctn.org Identifier: ISRCTN17271094.

Melanocortin 4 receptor agonism enhances sexual brain processing in women with hypoactive sexual desire disorder

BACKGROUND

Hypoactive sexual desire disorder (HSDD) is characterized by a persistent deficiency of sexual fantasies and desire for sexual activity, causing marked distress and interpersonal difficulty. It is the most prevalent female sexual health problem globally, affecting approximately 10% of women, but has limited treatment options. Melanocortin 4 receptor (MC4R) agonists have emerged as a promising therapy for women with HSDD, through unknown mechanisms. Studying the pathways involved is crucial for our understanding of normal and abnormal sexual behavior.

METHODS

Using psychometric, functional neuroimaging, and hormonal analyses, we conducted a randomized, double-blinded, placebo-controlled, crossover clinical study to assess the effects of MC4R agonism compared with placebo on sexual brain processing in 31 premenopausal heterosexual women with HSDD.

RESULTS

MC4R agonism significantly increased sexual desire for up to 24 hours after administration compared with placebo. During functional neuroimaging, MC4R agonism enhanced cerebellar and supplementary motor area activity and deactivated the secondary somatosensory cortex, specifically in response to visual erotic stimuli, compared with placebo. In addition, MC4R agonism enhanced functional connectivity between the amygdala and the insula during visual erotic stimuli compared with placebo.

CONCLUSION

These data suggest that MC4R agonism enhanced sexual brain processing by reducing self-consciousness, increasing sexual imagery, and sensitizing women with HSDD to erotic stimuli. These findings provide mechanistic insight into the action of MC4R agonism in sexual behavior and are relevant to the ongoing development of HSDD therapies and MC4R agonist development more widely.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04179734.

FUNDING

This is an investigator-sponsored study funded by AMAG Pharmaceuticals Inc., the Medical Research Council (MRC) (MR/T006242/1), and the National Institute for Health Research (NIHR) (CS-2018-18-ST2-002 and RP-2014-05-001).

Effects of Kisspeptin Administration in Women With Hypoactive Sexual Desire Disorder: A Randomized Clinical Trial

IMPORTANCE

Despite being the most common female sexual health complaint worldwide, current treatment options for hypoactive sexual desire disorder (HSDD) are limited in their safety and effectiveness. The hormone kisspeptin is a key endogenous activator of the reproductive hormonal axis with additional emerging roles in sexual and emotional behavior; however, its effects in women with HSDD are unknown.

OBJECTIVE

To test the hypothesis that kisspeptin enhances sexual and attraction brain processing in women with HSDD.

DESIGN, SETTING, AND PARTICIPANTS

This randomized clinical trial was double-masked and placebo controlled with a 2-way crossover. The trial was conducted in a university research setting in the UK from October 2020 to April 2021. Eligible participants were premenopausal women with HSDD. Functional neuroimaging, psychometric, and hormonal analyses were employed to investigate the effects of kisspeptin administration on brain processing, in response to erotic stimuli (erotic videos) and facial attraction (face images of varying attractiveness). Data were analyzed from May to December 2021.

INTERVENTIONS

A 75-minute intravenous infusion of kisspeptin-54 (1 nmol/kg/h) vs equivalent-rate placebo infusion.

MAIN OUTCOMES AND MEASURES

Blood oxygen level-dependent responses across the whole brain and regions of interest during kisspeptin vs placebo administration in response to erotic and facial attraction stimuli.

RESULTS

Of the 40 participants who were randomized, 32 women completed both kisspeptin and placebo visits, with a mean (SE) age of 29.2 (1.2) years. Kisspeptin administration resulted in modulations in sexual and facial attraction brain processing (deactivation of the left inferior frontal gyrus: Z max, 3.76; P = .01; activation of the right postcentral and supramarginal gyrus: Z max, 3.73; P < .001; deactivation of the right temporoparietal junction: Z max 4.08; P = .02). Furthermore, positive correlations were observed between kisspeptin-enhanced hippocampal activity in response to erotic videos, and baseline distress relating to sexual function (r = 0.469; P = .007). Kisspeptin's enhancement of posterior cingulate cortex activity in response to attractive male faces also correlated with reduced sexual aversion, providing additional functional significance (r = 0.476, P = .005). Kisspeptin was well-tolerated with no reported adverse effects.

CONCLUSIONS AND RELEVANCE

These findings lay the foundations for clinical applications for kisspeptin in women with HSDD.

TRIAL REGISTRATION

ISRCTN trial registry identifier: ISRCTN17271094.

Validity and utility of Hierarchical Taxonomy of Psychopathology (HiTOP): III. Emotional dysfunction superspectrum

The Hierarchical Taxonomy of Psychopathology (HiTOP) is a quantitative nosological system that addresses shortcomings of traditional mental disorder diagnoses, including arbitrary boundaries between psychopathology and normality, frequent disorder co-occurrence, substantial heterogeneity within disorders, and diagnostic unreliability over time and across clinicians. This paper reviews evidence on the validity and utility of the internalizing and somatoform spectra of HiTOP, which together provide support for an emotional dysfunction superspectrum. These spectra are composed of homogeneous symptom and maladaptive trait dimensions currently subsumed within multiple diagnostic classes, including depressive, anxiety, trauma-related, eating, bipolar, and somatic symptom disorders, as well as sexual dysfunction and aspects of personality disorders. Dimensions falling within the emotional dysfunction superspectrum are broadly linked to individual differences in negative affect/neuroticism. Extensive evidence establishes that dimensions falling within the superspectrum share genetic diatheses, environmental risk factors, cognitive and affective difficulties, neural substrates and biomarkers, childhood temperamental antecedents, and treatment response. The structure of these validators mirrors the quantitative structure of the superspectrum, with some correlates more specific to internalizing or somatoform conditions, and others common to both, thereby underlining the hierarchical structure of the domain. Compared to traditional diagnoses, the internalizing and somatoform spectra demonstrated substantially improved utility: greater reliability, larger explanatory and predictive power, and greater clinical applicability. Validated measures are currently available to implement the HiTOP system in practice, which can make diagnostic classification more useful, both in research and in the clinic.

Bremelanotide for Treatment of Female Hypoactive Sexual Desire

Hypoactive sexual desire disorder (HSDD) is a persistent deficiency or absence of sexual fantasies and desire resulting in significant distress or interpersonal difficulty. Women with this disorder may display a lack of motivation for sexual activity, reduced responsiveness to erotic cues, a loss of interest during sexual activity, and avoidance of situations that could lead to sexual activity. The pathophysiology of HSDD is thought to be centered around inhibitory and excitatory hormones, neurotransmitters, and specific brain anatomy. Due to the multifactorial nature of HSDD, treatment can be complex and must attempt to target the biological and psychosocial aspects of the disorder. Bremelanotide is a melanocortin receptor agonist and has been recently approved by the FDA to treat HSDD. Bremelanotide is administered intranasally or as a subcutaneous injection. The recommended dosage of bremelanotide is 1.75 mg injected subcutaneously in the abdomen or thigh at least 45 min before sexual activity. Studies showed improvements in desire, arousal, and orgasm scores when 1.75 mg of bremelanotide was administered before sexual activity compared to a placebo. Bremelanotide is a promising way to treat HSDD.

The Effect of Mindfulness-Based Cognitive-Behavioral Sex Therapy on Improving Sexual Desire Disorder, Sexual Distress, Sexual Self-Disclosure and Sexual Function in Women: A Randomized Controlled Clinical Trial

Sexual desire disorder is the most common form of sexual dysfunction among women and is associated with problems like sexual distress and reduced sexual self-disclosure. As a result, this RCT study was conducted with 70 reproductive-age women in the form of 4 weekly group educational sessions. Compared to the control group, the mindfulness-based cognitive-behavioral sex therapy (MBCST) intervention significantly improved sexual -desire, -distress, self-disclosure and -function immediately, 4 and 12 weeks after the educational sessions were completed in the intervention group (p < 0.001). Overall, our findings underscore the significance of the MBCST intervention on improving sexual dysfunction among women.Trial registration number: Iranian registry of clinical trials. IRCT Id: IRCT20160808029255N4.Trial registration date: 17th September 2018.Date of first patient's enrollment: 19th September 2018.Supplemental data for this article is available online at https://doi.org/10.1080/0092623X.2021.2008075.

Hypoactive Sexual Desire Disorder in Women: Physiology, Assessment, Diagnosis, and Treatment

Nearly half of women in the United States report problems with sexual function. Many health care providers do not ask about sexual concerns during routine clinical encounters because of personal discomfort, lack of familiarity with treatment, or the belief that they lack adequate time to address this complex issue. This may be especially true for hypoactive sexual desire disorder (HSDD), the most commonly identified sexual problem among women. HSDD is characterized by a deficiency of sexual thoughts, feelings, or receptiveness to sexual stimulation that has been present for at least 6 months, causes personal distress, and is not due to another medical condition. This is an up-to-date overview of HSDD for clinicians, discussing its physiology, assessment, diagnosis, and treatment strategies. Although a definitive physiology of HSDD is still unknown, multiple hormones and neurotransmitters likely participate in a dual-control model to balance excitation and inhibition of sexual desire. For assessment and diagnosis, validated screening tools are discussed, and the importance of a biopsychosocial assessment is emphasized, with guidance on how this can be implemented in clinical encounters. The 2 recently approved medications for HSDD, flibanserin and bremelanotide, are reviewed as well as off-label treatments. Overall, HSDD represents a common yet likely underrecognized disorder that midwives and other health care providers who care for women across the life span are in a unique position to address.

Understanding heterosexual women's erotic flexibility: the role of attention in sexual evaluations and neural responses to sexual stimuli

Many women experience desires, arousal and behavior that run counter to their sexual orientation (orientation inconsistent, 'OI'). Are such OI sexual experiences cognitively and neurobiologically distinct from those that are consistent with one's sexual orientation (orientation consistent, 'OC')? To address this question, we employed a mindful attention intervention-aimed at reducing judgment and enhancing somatosensory attention-to examine the underlying attentional and neurobiological processes of OC and OI sexual stimuli among predominantly heterosexual women. Women exhibited greater neural activity in response to OC, compared to OI, sexual stimuli in regions associated with implicit visual processing, volitional appraisal and attention. In contrast, women exhibited greater neural activity to OI, relative to OC, sexual stimuli in regions associated with complex visual processing and attentional shifting. Mindfully attending to OC sexual stimuli reduced distraction, amplified women's evaluations of OC stimuli as sexually arousing and deactivated the superior cerebellum. In contrast, mindfully attending to OI sexual stimuli amplified distraction, decreased women's evaluations of OI stimuli as sexually arousing and augmented parietal and temporo-occipital activity. Results of the current study constrain hypotheses of female erotic flexibility, suggesting that sexual orientation may be maintained by differences in attentional processing that cannot be voluntarily altered.

Hypoactive sexual desire disorder (HSDD) is not "female erectile dysfunction (ED)": challenges with the characterization of HSDD in women based on a systematic literature review

Objective: Hypoactive sexual desire disorder (HSDD) in women has been viewed inaccurately by some in the medical and payer community as analogous to erectile dysfunction (ED) in men. This literature review aims to highlight the distinctions between HSDD and ED.Methods: Two systematic literature searches were conducted on the epidemiology, symptomatology and biopsychosocial outcomes of HSDD and ED. Studies published since 2007 were considered for HSDD; studies published since 2012 were considered for ED.Results: HSDD in women is primarily a central nervous system condition related to neuroendocrine factors, whereby neural pathways that regulate sexual excitation and/or inhibition appear to be involved. A combination of organic and psychogenic factors often contributes to ED. HSDD and ED are associated with similar psychological and interpersonal consequences, but affect different phases of the sexual response model (desire versus arousal) and have different pathophysiologies, therefore requiring different treatment and outcome paradigms. ED is measured by objective, physiological responses (erection and sexual function), but quantitative assessments for HSDD are more difficult because loss of desire with associated distress has to be assessed. Outcome measures used to assess ED, such as the number of satisfying sexual events, are far less informative as an endpoint for randomized clinical trials of treatments for HSDD.Conclusions: HSDD and ED are distinct conditions affecting different phases of the sexual response model, and thus require clear and unique clinical characterization and adequate communication between the health care professional and patient for appropriate diagnosis, management and treatment.

Associations Between Altered Cerebral Activity Patterns and Psychosocial Disorders in Patients With Psychogenic Erectile Dysfunction: A Mediation Analysis of fMRI

Previous studies had illustrated the significant neural pathological changes in patients with psychogenic erectile dysfunction (pED), while few works focused on the neural underpinning of the psychosocial status in patients with pED. This study aimed to investigate the associations among the altered cerebral activity patterns, impaired erectile function, and the disrupted psychosocial status in patients with pED. Thirty-two patients with pED and 28 healthy controls (HCs) were included. The amplitude of low-frequency fluctuations (ALFF), region-of-interest-based functional connectivity (FC), as well as Pearson correlation analyses and mediation analyses between neuroimaging outcomes and clinical outcomes were performed. Compared to HCs, patients with pED manifested lower erectile function, disrupted psychosocial status, as well as decreased ALFF in the left dorsolateral prefrontal cortex (dlPFC) and reduced FC between the left dlPFC and left angular gyrus, and left posterior cingulate cortex (PCC) and precuneus, which belonged to the default mode network (DMN). Moreover, both the ALFF of the left dlPFC and FC between the left dlPFC and left PCC and precuneus were significantly correlated with the sexual function and psychosocial status in patients with pED. The disrupted psychosocial status mediated the influence of atypical FC between dlPFC and DMN on decreased erectile function. This study widened our understanding of the important role of psychosocial disorders in pathological neural changes in patients with pED.

The Relational and Bodily Experiences Theory of Sexual Desire in Women

We review the theory and research on women's sexual desire and present a theory that incorporates internalized representations of relational and bodily experiences into our understanding of the full range of desire in women. To this end, we move away from the current tendency to focus on low sexual desire in women and instead consider desire on a spectrum or continuum from absent or diminished to high desire across multiple sexual orientations, including heterosexual, bisexual, and lesbian. We review definitions of sexual desire, as well as the epidemiology and etiology of hypoactive sexual desire, the most prevalent sexual complaint in women, including the biological, psychological, and relationship correlates of inhibited sexual desire. Subsequently, we examine the research on highly sexual women, who tend to experience high levels of sexual desire, sexual agency, and sexual esteem, and distinguish between high sexual desire and hypersexuality. We introduce two important constructs that are integrated into the Relational and Bodily Experiences Theory (RBET) of sexual desire in women: attachment and sexual body self-representations, suggesting that women's internalized representations of self and other that stem from childhood and their capacity to embody their sexual bodies are integral to our understanding of the phenomenology of sexual desire in women. RBET calls for further research into the links between attachment, sexual body self-representations, and desire, and suggests that clinical interventions for sexual desire difficulties in women should emphasize internalized working models of relationships (i.e., attachment) and integrate bodily based approaches.

The Woman's Body (Not the Man's One) Is Used to Evaluate Sexual Desire: An Eye-Tracking Study of Automatic Visual Attention

INTRODUCTION

Vision of the human body has been shown to be key in eliciting sexual desire. However, whether the visual pattern characterizing sexual desire is different in women and men is still unclear.

AIM

To investigate the effect of gender on visual patterns triggered by an identical set of stimuli depicting attractive heterosexual couples.

METHODS

Heterosexual women and men (n = 106) were tested on a picture-viewing task associated with eye tracking. The context of sexual desire was activated by asking the participant whether they perceived such desire while looking at sensual pictures of heterosexual couples. Data were analyzed using mixed-subject design analyses of variance.

MAIN OUTCOME MEASURE

Fixation durations were used to investigate visual patterns. 2 areas of interest were created to investigate visual patterns (face vs body area).

RESULTS

Results showed longer fixations on body rather than face areas irrespective of participant gender. Moreover, all participants looked longer at women's than men's bodies and at the faces of the opposite sex.

CLINICAL IMPLICATIONS

These findings shed light on the automatic processes underlying sexual desire, which has the potential to improve the care of patients suffering from sexual disorders by optimizing interventions.

STRENGTHS & LIMITATIONS

The strengths of this study are the use of an eye-tracking paradigm, the dissociation between 2 fixation areas (ie, face and body), and the use of an identical set of stimuli allowing an accurate between-gender comparison of the visual pattern. The limitations are the small sample size, the use of healthy heterosexual individuals, and the absence of measures of sexual arousal and genital response.

CONCLUSIONS

These findings confirm the association between the human body and sexual desire. They also reveal the unique attentional attractiveness of woman's bodies across genders. Bolmont M, Bianchi-Demicheli F, Boisgontier MP, et al. The Woman's Body (Not the Man's One) Is Used to Evaluate Sexual Desire: An Eye-Tracking Study of Automatic Visual Attention. J Sex Med 2019;16:195-202.

Spatio-temporal dynamics of the mirror neuron system during social intentions

Previous research has shown that specific goals and intentions influence a person's allocation of social attention. From a neural viewpoint, a growing body of evidence suggests that the inferior fronto-parietal network, including the mirror neuron system, plays a role in the planning and the understanding of motor intentions. However, it is unclear whether and when the mirror neuron system plays a role in social intentions. Combining a behavioral task with electrical neuroimaging in 22 healthy male participants, the current study investigates whether the temporal brain dynamic of the mirror neuron system differs during two types of social intentions i.e., lust vs. romantic intentions. Our results showed that 62% of the stimuli evoking lustful intentions also evoked romantic intentions, and both intentions were sustained by similar activations of the inferior frontal gyrus and the inferior parietal lobule/angular gyrus for the first 432 ms after stimulus onset. Intentions to not love or not lust, on the other hand, were characterized by earlier differential activations of the inferior fronto-parietal network i.e., as early as 244 ms after stimulus onset. These results suggest that the mirror neuron system may not only code for the motor correlates of intentions, but also for the social meaning of intentions and its valence at both early/automatic and later/more elaborative stages of information processing.