The human sexual response cycle: brain imaging evidence linking sex to other pleasures

Brain Imaging of Human Sexual Response: Recent Developments and Future Directions

PURPOSE OF REVIEW

The purpose of this study is to provide a comprehensive summary of the latest developments in the experimental brain study of human sexuality, focusing on brain connectivity during the sexual response.

RECENT FINDINGS

Stable patterns of brain activation have been established for different phases of the sexual response, especially with regard to the wanting phase, and changes in these patterns can be linked to sexual response variations, including sexual dysfunctions. From this solid basis, connectivity studies of the human sexual response have begun to add a deeper understanding of the brain network function and structure involved.

SUMMARY

The study of "sexual" brain connectivity is still very young. Yet, by approaching the brain as a connected organ, the essence of brain function is captured much more accurately, increasing the likelihood of finding useful biomarkers and targets for intervention in sexual dysfunction.

Mediating Role of the Reward Network in the Relationship between the Dopamine Multilocus Genetic Profile and Depression

Multiple genetic loci in the dopamine (DA) pathway have been associated with depression symptoms in patients with major depressive disorder (MDD). However, the neural mechanisms underlying the polygenic effects of the DA pathway on depression remain unclear. We used an imaging genetic approach to investigate the polygenic effects of the DA pathway on the reward network in MDD. Fifty-three patients and 37 cognitively normal (CN) subjects were recruited and underwent resting-state functional magnetic resonance imaging (R-fMRI) scans. Multivariate linear regression analysis was employed to measure the effects of disease and multilocus genetic profile scores (MGPS) on the reward network, which was constructed using the nucleus accumbens (NAc) functional connectivity (NAFC) network. DA-MGPS was widely associated within the NAFC network, mainly in the inferior frontal cortex, insula, hypothalamus, superior temporal gyrus, and occipital cortex. The pattern of DA-MGPS effects on the fronto-striatal pathway differed in MDD patients compared with CN subjects. More importantly, NAc-putamen connectivity mediates the association between DA MGPS and anxious depression traits in MDD patients. Our findings suggest that the DA multilocus genetic profile makes a considerable contribution to the reward network and anxious depression in MDD patients. These results expand our understanding of the pathophysiology of polygenic effects underlying brain network abnormalities in MDD.

Noradrenergic modulation of neural erotic stimulus perception

We recently investigated neuromodulatory effects of the noradrenergic agent reboxetine and the dopamine receptor affine amisulpride in healthy subjects on dynamic erotic stimulus processing. Whereas amisulpride left sexual functions and neural activations unimpaired, we observed detrimental activations under reboxetine within the caudate nucleus corresponding to motivational components of sexual behavior. However, broadly impaired subjective sexual functioning under reboxetine suggested effects on further neural components. We now investigated the same sample under these two agents with static erotic picture stimulation as alternative stimulus presentation mode to potentially observe further neural treatment effects of reboxetine. 19 healthy males were investigated under reboxetine, amisulpride and placebo for 7 days each within a double-blind cross-over design. During fMRI static erotic picture were presented with preceding anticipation periods. Subjective sexual functions were assessed by a self-reported questionnaire. Neural activations were attenuated within the caudate nucleus, putamen, ventral striatum, the pregenual and anterior midcingulate cortex and in the orbitofrontal cortex under reboxetine. Subjective diminished sexual arousal under reboxetine was correlated with attenuated neural reactivity within the posterior insula. Again, amisulpride left neural activations along with subjective sexual functioning unimpaired. Neither reboxetine nor amisulpride altered differential neural activations during anticipation of erotic stimuli. Our results verified detrimental effects of noradrenergic agents on neural motivational but also emotional and autonomic components of sexual behavior. Considering the overlap of neural network alterations with those evoked by serotonergic agents, our results suggest similar neuromodulatory effects of serotonergic and noradrenergic agents on common neural pathways relevant for sexual behavior.

Not all about sex: neural and biobehavioral functions of human dance

This paper provides an integrative review of neuroscientific and biobehavioral evidence about the effects of dance on the individual across cultural differences. Dance moves us, and many derive aesthetic pleasure from it. However, in addition-and beyond aesthetics-we propose that dance has noteworthy, deeper neurobiological effects. We first summarize evidence that illustrates the centrality of dance to human life indirectly from archaeology, comparative psychology, developmental psychology, and cross-cultural psychology. Second, we review empirical evidence for six neural and biobehavioral functions of dance: (1) attentional focus/flow, (2) basic emotional experiences, (3) imagery, (4) communication, (5) self-intimation, and (6) social cohesion. We discuss the reviewed evidence in relation to current debates in the field of empirical enquiry into the functions of human dance, questioning the positions that dance is (1) just for pleasure, (2) all about sex, (3) just for mood management and well-being, and (4) for experts only. Being a young field, evidence is still piecemeal and inconclusive. This review aims to take a step toward a systematization of an emerging avenue of research: a neuro- and biobehavioral science of dance.

Individual prolactin reactivity modulates response of nucleus accumbens to erotic stimuli during acute cannabis intoxication: an fMRI pilot study

RATIONALE

Self-report studies indicate that cannabis could increase sexual desire in some users. We hypothesized that intoxication increases activation of brain areas responsive to visual erotica, which could be useful in the treatment of hypoactive sexual desire disorder, a condition marked by a lack of sexual desire.

OBJECTIVES

The aim of this study is to assess the aphrodisiacal properties of cannabis.

METHODS

We conducted an open-randomized study with 21 heterosexual casual cannabis users. A 3T MRI was used to measure brain activation in response to erotic pictures. Blood samples were collected to determine the serum levels of cannabinoids, cortisol and prolactin. Participants were grouped according to whether they had ever experienced any aphrodisiacal effects during intoxication (Group A) or not (Group non-A).

RESULTS

Intoxication was found to significantly increase activation in the right nucleus accumbens in the Group A while significantly decreasing activation in the Group non-A. There was also a significant interaction between the group and intoxication, with elevated prolactin in the Group non-A during intoxication. No intoxication-related differences in subjective picture evaluations were found.

CONCLUSION

Cannabis intoxication increases activation of the right nucleus accumbens to erotic stimuli. This effect is limited to users whose prolactin is not elevated in response to intoxication. This effect may be useful in the treatment of low sexual desire.

The Physiology of Female Sexual Function and the Pathophysiology of Female Sexual Dysfunction (Committee 13A)

INTRODUCTION

The article consists of six sections written by separate authors that review female genital anatomy, the physiology of female sexual function, and the pathophysiology of female sexual dysfunction but excluding hormonal aspects.

AIM

To review the physiology of female sexual function and the pathophysiology of female sexual dysfunction especially since 2010 and to make specific recommendations according to the Oxford Centre for evidence based medicine (2009) "levels of evidence" wherever relevant.

CONCLUSION

Recommendations were made for particular studies to be undertaken especially in controversial aspects in all six sections of the reviewed topics. Despite numerous laboratory assessments of female sexual function, genital assessments alone appear insufficient to characterise fully the complete sexual response.

The Affective Core of Emotion: Linking Pleasure, Subjective Well-Being, and Optimal Metastability in the Brain

Arguably, emotion is always valenced-either pleasant or unpleasant-and dependent on the pleasure system. This system serves adaptive evolutionary functions; relying on separable wanting, liking, and learning neural mechanisms mediated by mesocorticolimbic networks driving pleasure cycles with appetitive, consummatory, and satiation phases. Liking is generated in a small set of discrete hedonic hotspots and coldspots, while wanting is linked to dopamine and to larger distributed brain networks. Breakdown of the pleasure system can lead to anhedonia and other features of affective disorders. Eudaimonia and well-being are difficult to study empirically, yet whole-brain computational models could offer novel insights (e.g., routes to eudaimonia such as caregiving of infants or music) potentially linking eudaimonia to optimal metastability in the pleasure system.

Lessons learned from the study of masturbation and its comorbidity with psychiatric disorders in children: The first analytic study

Background

The main source of information about children’s masturbation is more on the basis of case reports. Due to the lack of consistent and accurate information.

Objective

This study aimed to determine prevalence and underlying factors of masturbation and its comorbidity with psychiatric disorders in children.

Methods

In this descriptive-analytical study, among the children referred to the Pediatrics Clinic of Psychiatric Ward, Golestan Hospital, Ahvaz, Southwest Iran, 98 children were selected by convenience sampling in 2014. Disorders were diagnosed by clinical interview based on the fourth edition of the Diagnostic and Statistical Manual for Psychiatric Disorders (DSM-IV) and the Child Symptom Inventory-4 (CSI-4). We also used a questionnaire, containing demographic information about the patient and their family and also other data. Data was analyzed using descriptive statistics and chi-square test with SPSS software version 16.

Results

Of the children who participated in this study (most of whom were boys), 31.6% suffered from masturbation. The phobias (p=0.002), separation anxiety disorder (p=0.044), generalized anxiety disorder (p=0.037), motor tics (p=0.033), stress disorder (p=0.005), oppositional defiant disorder (p=0.044), thumb sucking (p=0.000) and conduct disorder (p=0.001) were associated with masturbation.

Conclusion

Masturbation was common in children referred to psychiatric clinic, and may be more associated with oppositional defiant disorder, or conduct disorder, some anxiety disorders, motor tics and other stereotypical behavior. Authors recommended more probing for psychiatric disorders in children with unusual sexual behavior.

Functional insights into aberrant brain responses and integration in patients with lifelong premature ejaculation

Even though lifelong premature ejaculation (PE) is highly prevalent, few studies have investigated the neural mechanisms underlying PE. The extent and pattern of brain activation can be determined through a version of functional magnetic resonance imaging (fMRI) with erotic picture stimuli (task fMRI) and a resting-state fMRI (rs fMRI). We showed that the brain activity in the left inferior frontal gyrus and left insula was decreased both during the task and in the resting state, while there was higher activation in the right middle temporal gyrus during the task. Higher functional connectivity was found in PE between those three brain areas and the bilateral middle cingulate cortex, right middle frontal gyrus and supplementary motor area. Moreover, the brain activity had positive correlation with clinical rating scales, such as intravaginal ejaculatory latency time (IELT) and the Chinese Index of Premature Ejaculation (CIPE). These findings revealed that brain responses and functional integration in certain brain areas are impaired in cases of PE, which was consistently supported by multiple measurements obtained using a task and rs fMRI approach.

Neural Correlates of Sexual Orientation in Heterosexual, Bisexual, and Homosexual Men

Studies of subjective and genital sexual arousal in monosexual (i.e. heterosexual and homosexual) men have repeatedly found that erotic stimuli depicting men’s preferred sex produce strong responses, whereas erotic stimuli depicting the other sex produce much weaker responses. Inconsistent results have previously been obtained in bisexual men, who have sometimes demonstrated distinctly bisexual responses, but other times demonstrated patterns more similar to those observed in monosexual men. We used fMRI to investigate neural correlates of responses to erotic pictures and videos in heterosexual, bisexual, and homosexual men, ages 25–50. Sixty participants were included in video analyses, and 62 were included in picture analyses. We focused on the ventral striatum (VS), due to its association with incentive motivation. Patterns were consistent with sexual orientation, with heterosexual and homosexual men showing female-favoring and male-favoring responses, respectively. Bisexual men tended to show less differentiation between male and female stimuli. Consistent patterns were observed in the whole brain, including the VS, and also in additional regions such as occipitotemporal, anterior cingulate, and orbitofrontal cortices. This study extends previous findings of gender-specific neural responses in monosexual men, and provides initial evidence for distinct brain activity patterns in bisexual men.

Disrupted reward circuits is associated with cognitive deficits and depression severity in major depressive disorder

Neuroimaging studies have demonstrated that major depressive disorder (MDD) patients show blunted activity responses to reward-related tasks. However, whether abnormal reward circuits affect cognition and depression in MDD patients remains unclear. Seventy-five drug-naive MDD patients and 42 cognitively normal (CN) subjects underwent a resting-state functional magnetic resonance imaging scan. The bilateral nucleus accumbens (NAc) were selected as seeds to construct reward circuits across all subjects. A multivariate linear regression analysis was employed to investigate the neural substrates of cognitive function and depression severity on the reward circuits in MDD patients. The common pathway underlying cognitive deficits and depression was identified with conjunction analysis. Compared with CN subjects, MDD patients showed decreased reward network connectivity that was primarily located in the prefrontal-striatal regions. Importantly, distinct and common neural pathways underlying cognition and depression were identified, implying the independent and synergistic effects of cognitive deficits and depression severity on reward circuits. This study demonstrated that disrupted topological organization within reward circuits was significantly associated with cognitive deficits and depression severity in MDD patients. These findings suggest that in addition to antidepressant treatment, normalized reward circuits should be a focus and a target for improving depression and cognitive deficits in MDD patients.

Mood changes after watching pornography on the Internet are linked to tendencies towards Internet-pornography-viewing disorder

Internet-pornography-viewing disorder (IPD) is considered one type of Internet-use disorder. For IPD's development, it was assumed theoretically that a dysfunctional use of Internet pornography to cope with depressive mood or stress might be considered to be a risk factor. To address the effect of Internet pornography use on mood, an online study with three measuring points with a sample of male participants was conducted. Participants were investigated regarding their tendencies towards IPD, personal use of Internet pornography, general mood, perceived stress, and their Internet pornography use motivation. Moreover, participants were asked regarding their current mood, sexual arousal, and need to masturbate before and after they watched Internet pornography self-determinedly in a private environment. Data showed that tendencies towards IPD were associated negatively with feeling generally good, awake, and calm and were correlated positively with perceived stress in daily life and using Internet pornography for excitation seeking and emotional avoidance. Self-determined use of Internet pornography in their private environment was accompanied by changes in mood and indicators of sexual arousal. Moreover, tendencies towards IPD were negatively related to mood before and after Internet-pornography use as well as an actual increase of good and calm mood. The results showed effects of watching Internet pornography on mood and sexual arousal which can be considered having reinforcing effects for the user. Thus, the results are in line with theoretical assumptions on IPD's development, in which the positive (and negative) reinforcement received by Internet-pornography use is related to cue-reactivity and craving reactions.

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Investigation of mood and sexual arousal before and after self-determined Internet pornography use in private environment

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Watching pornography was associated to changes in mood and indicators of sexual arousal

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Current mood as well as changes in mood were associated to symptoms of Internet-pornography-viewing-disorder

EEG to Primary Rewards: Predictive Utility and Malleability by Brain Stimulation

Theta burst stimulation (TBS) is thought to affect reward processing mechanisms, which may increase and decrease reward sensitivity. To test the ability of TBS to modulate response to strong primary rewards, participants hypersensitive to primary rewards were recruited. Twenty men and women with at least two opposite-sex, sexual partners in the last year received two forms of TBS. Stimulations were randomized to avoid order effects and separated by 2 hours to reduce carryover. The two TBS forms have been demonstrated to inhibit (continuous) or excite (intermittent) the left dorsolateral prefrontal cortex using different pulse patterns, which links to brain areas associated with reward conditioning. After each TBS, participants completed tasks assessing their reward responsiveness to monetary and sexual rewards. Electroencephalography (EEG) was recorded. They also reported their number of orgasms in the weekend following stimulation. This signal was malleable by TBS, where excitatory TBS resulted in lower EEG alpha relative to inhibitory TBS to primary rewards. EEG responses to sexual rewards in the lab (following both forms of TBS) predicted the number of orgasms experienced over the forthcoming weekend. TBS may be useful in modifying hypersensitivity or hyposensitivity to primary rewards that predict sexual behaviors. Since TBS altered the anticipation of a sexual reward, TBS may offer a novel treatment for sexual desire problems.

What is orgasm? A model of sexual trance and climax via rhythmic entrainment

Orgasm is one of the most intense pleasures attainable to an organism, yet its underlying mechanisms remain poorly understood. On the basis of existing literatures, this article introduces a novel mechanistic model of sexual stimulation and orgasm. In doing so, it characterizes the neurophenomenology of sexual trance and climax, describes parallels in dynamics between orgasms and seizures, speculates on possible evolutionary origins of sex differences in orgasmic responding, and proposes avenues for future experimentation. Here, a model is introduced wherein sexual stimulation induces entrainment of coupling mechanical and neuronal oscillatory systems, thus creating synchronized functional networks within which multiple positive feedback processes intersect synergistically to contribute to sexual experience. These processes generate states of deepening sensory absorption and trance, potentially culminating in climax if critical thresholds are surpassed. The centrality of rhythmic stimulation (and its modulation by salience) for surpassing these thresholds suggests ways in which differential orgasmic responding between individuals-or with different partners-may serve as a mechanism for ensuring adaptive mate choice. Because the production of rhythmic stimulation combines honest indicators of fitness with cues relating to potential for investment, differential orgasmic response may serve to influence the probability of continued sexual encounters with specific mates.

Contextual modulation of pain in masochists: involvement of the parietal operculum and insula

Pain can be modulated by contextual stimuli, such as emotions, social factors, or specific bodily perceptions. We presented painful laser stimuli together with body-related masochistic visual stimuli to persons with and without preferred masochistic sexual behavior and used neutral, positive, and negative pictures with and without painful stimuli as control. Masochists reported substantially reduced pain intensity and unpleasantness in the masochistic context compared with controls but had unaltered pain perception in the other conditions. Functional magnetic resonance imaging revealed that masochists activated brain areas involved in sensory-discriminative processing rather than affective pain processing when they received painful stimuli on a masochistic background. The masochists compared with the controls displayed attenuated functional connectivity of the parietal operculum with the left and right insulae, the central operculum, and the supramarginal gyrus. Masochists additionally showed negative correlations between the duration of interest in masochistic activities and activation of areas involved in motor activity and affective processing. We propose that the parietal operculum serves as an important relay station that attenuates the affective-motivational aspects of pain in masochists. This novel mechanism of pain modulation might be related to multisensory integration and has important implications for the assessment and treatment of pain.

The neural basis of sex differences in sexual behavior: A quantitative meta-analysis

Sexuality as to its etymology presupposes the duality of sexes. Using quantitative neuroimaging meta-analyses, we demonstrate robust sex differences in the neural processing of sexual stimuli in thalamus, hypothalamus, and basal ganglia. In a narrative review, we show how these relate to the well-established sex differences on the behavioral level. More specifically, we describe the neural bases of known poor agreement between self-reported and genital measures of female sexual arousal, of previously proposed male proneness to affective sexual conditioning, as well as hints of unconscious activation of bonding mechanisms during sexual stimulation in women. In summary, our meta-analytic review demonstrates that neurofunctional sex differences during sexual stimulation can account for well-established sex differences in sexual behavior.

Neural Representation of Subjective Sexual Arousal in Men and Women

INTRODUCTION

Studies investigating brain indices of sexual arousal have begun to elucidate the brain's role in processing subjective arousal; however, most research has focused on men, used discrete ratings of subjective arousal, and used stimuli too short to induce significant arousal in women.

AIM

To examine brain regions modulated by changes in subjective sexual arousal (SSA) rating intensity in men and women.

METHODS

Two groups (20 men, 20 women) viewed movie clips (erotic or humorous) while continuously evaluating changes in their SSA using a Likert-like scale (0 = not aroused, 10 = most aroused) and answering discrete questions about liking the movies and wanting sexual stimulation. Brain activity was measured using functional magnetic resonance imaging.

MAIN OUTCOME MEASURES

Blood oxygen level-dependent responses and continuous and discrete measurements of sexual arousal.

RESULTS

Erotic movies induced significant SSA in men and women. No sex difference in mean SSA was found in response to the erotic movies on continuous or discrete measurements. Several brain regions were correlated with changes in SSA. Parametric modulation with rating intensity showed a specific group of regions within the parietal lobe that showed significant differences in activity among low, medium, and high SSA.

CONCLUSION

Multiple regions were concordant with changes in SSA; however, a subset of regions in men and women was modulated by SSA intensity, a subset previously linked to attentional processes, monitoring of internal body representation, and processing of sensory information from the genitals. This study highlights that similar brain regions are activated during subjective assessment of sexual arousal in men and women. The data further highlight the fact that SSA is a complex phenomenon made up of multiple interoceptive and attentional processes.

[Functional results and treatment of functional dysfunctions after radical prostatectomy]

OBJECTIVE

To describe the functional results and treatment of functional dysfunctions after radical prostatectomy for localized prostate cancer.

MATERIAL AND METHOD

Bibliography search was performed from the database Medline (National Library of Medicine, Pubmed) selected according to the scientific relevance. The research was focused on continence, potency, les dyserections, couple sexuality, incontinence, treatments of postoperative incontinence, dysrection and trifecta.

RESULTS

Radical prostatectomy is an elaborate and challenging procedure when carcinological risk balances with functional results. Despite recent developments in surgical techniques, post-radical prostatectomy urinary incontinence (pRP-UI) continues to be one of the most devastating complications, which affects 9-16% of patients. Sphincter injury and bladder dysfunction are the most common causes or pRP-UI. The assessment of severity of pRP-UI that affects the choice of treatment is still not well standardized but should include at least a pad test and self-administered questionnaires. The implantation of an artificial urinary sphincter AMS800 remains the gold standard treatment for patients with moderate to severe pRP-UI. The development of less invasive techniques such as the male sling of Pro-ACT balloons has provided alternative therapeutic options for moderate and slight forms of pRP-UI. Most groups now consider the bulbo-urethral compressive sling as the treatment of choice for patients with non-severe pRP-UI. The most appropriate second-line therapeutic strategy is not clearly determined. Recent therapies such as adjustable artificial urinary sphincters and sling and stem cells injections have been investigated. Maintenance of a satisfying sex life is a major concern of a majority of men facing prostate cancer and its treatments. It is essential to assess the couple's sexuality before treating prostate cancer in order to deliver comprehensive information and consider early therapeutic solutions adapted to the couple's expectations. Active pharmacological erectile rehabilitation (intracavernous injections or phosphodiesterase type 5 inhibitors [PDE5i] on demand, during in the month following surgery) or passive (daily PDE5i after surgery) might improve the quality of erections especially in response to PDE5i. Unimpaired aspects of sexual response (orgasm) may, when the erection is not yet recovered, represent an alternative allowing the couple to preserve intimacy and complicity. Androgen blockade is a major barrier to maintain or return to a satisfying sex. Trifecta is a simple tool to present in one way the results of radical prostatectomy: in case of bilateral neurovascular preservation, Trifecta is 60% whatever the surgical approach.

CONCLUSION

Radical prostatectomy is an elaborate and challenging procedure when carcinological risk balances with functional results. Various treatments of postoperative incontinence and dysrections exist. Functional disorders after surgery have to be treated to ameliorate quality of life of patients.

Visual Sexual Stimuli-Cue or Reward? A Perspective for Interpreting Brain Imaging Findings on Human Sexual Behaviors

There is an increasing number of neuroimaging studies using visual sexual stimuli (VSS), especially within the emerging field of research on compulsive sexual behaviors (CSB). A central question in this field is whether behaviors such as excessive pornography consumption share common brain mechanisms with widely studied substance and behavioral addictions. Depending on how VSS are conceptualized, different predictions can be formulated within the frameworks of Reinforcement Learning or Incentive Salience Theory, where a crucial distinction is made between conditioned and unconditioned stimuli (related to reward anticipation vs. reward consumption, respectively). Surveying 40 recent human neuroimaging studies we show existing ambiguity about the conceptualization of VSS. Therefore, we feel that it is important to address the question of whether VSS should be considered as conditioned stimuli (cue) or unconditioned stimuli (reward). Here we present our own perspective, which is that in most laboratory settings VSS play a role of reward, as evidenced by: (1) experience of pleasure while watching VSS, possibly accompanied by genital reaction; (2) reward-related brain activity correlated with these pleasurable feelings in response to VSS; (3) a willingness to exert effort to view VSS similarly as for other rewarding stimuli such as money; and (4) conditioning for cues predictive of VSS. We hope that this perspective article will initiate a scientific discussion on this important and overlooked topic and increase attention for appropriate interpretations of results of human neuroimaging studies using VSS.

The efficacy, safety and ethics of the use of testosterone-suppressing agents in the management of sex offending

PURPOSE OF REVIEW

The use of endocrine medications to reduce sexual offending recidivism is established and may involve clinicians from diverse specialities. The present review aims to outline relevant background information and note a Medical Ethics framework upon which to facilitate decision-making.

RECENT FINDINGS

There have been several systematic reviews in recent years. A number of problems with research in the area of the medical treatment of sex offenders have been highlighted. There remains scope for improvement in the research to answer a number of relevant clinical issues. Nonetheless, some very useful indicators of relevance to clinical practice have emerged.

SUMMARY

The use of medication to manage the risk of sex offending in males is appropriate under the right circumstances. These include, for example, hypersexuality with sexual deviance and psychological-treatment interfering sexual preoccupation.

Altered Appetitive Conditioning and Neural Connectivity in Subjects With Compulsive Sexual Behavior

INTRODUCTION

There has been growing interest in a better understanding of the etiology of compulsive sexual behavior (CSB). It is assumed that facilitated appetitive conditioning might be an important mechanism for the development and maintenance of CSB, but no study thus far has investigated these processes.

AIM

To explore group differences in neural activity associated with appetitive conditioning and connectivity in subjects with CSB and a healthy control group.

METHODS

Two groups (20 subjects with CSB and 20 controls) were exposed to an appetitive conditioning paradigm during a functional magnetic resonance imaging experiment, in which a neutral stimulus (CS+) predicted visual sexual stimuli and a second stimulus (CS-) did not.

MAIN OUTCOME MEASURES

Blood oxygen level-dependent responses and psychophysiologic interaction.

RESULTS

As a main result, we found increased amygdala activity during appetitive conditioning for the CS+ vs the CS- and decreased coupling between the ventral striatum and prefrontal cortex in the CSB vs control group.

CONCLUSION

The findings show that neural correlates of appetitive conditioning and neural connectivity are altered in patients with CSB. The increased amygdala activation might reflect facilitated conditioning processes in patients with CSB. In addition, the observed decreased coupling could be interpreted as a marker for impaired emotion regulation success in this group.

Sex and Eating: Relationships Based on Wanting and Liking

Sex and eating may have behavioral and psychological relationships and have cortical regions in common. This research investigated the general relationship between sex and eating from a reward perspective among the general population. Two-hundred and sixty-one Chinese participants were recruited via the internet (136 males, 125 females, mean age 30.46 years) to fill in questionnaires about wanting and liking for sex and eating. The results revealed that first, there was a positive correlation between wanting for sex and wanting to eat only for males. Second, the relationship between liking for sex and eating was also positive for males and not significant in females. Third, the correlation between sociosexual orientation and wanting to eat was significant only in females, and there was no significant correlation between sociosexual orientation and liking for eating. Fourth, emotional sex cravings (or emotional sexual activity) was positively correlated with emotional food cravings (or emotional eating behavior), with a higher magnitude correlation in males than females. Finally, analysis of wanting (liking) models of sex and eating for males and females revealed three models for wanting among females: high wanting, low wanting for eating, and low wanting for sex; and two models for wanting among males: high wanting and low wanting. Liking for sex and eating among females consisted of two types of model: high liking and low liking; whereas three type models existed for males: high liking for sex, high liking for eating, and low liking. In general, our research revealed that, as with other natural reward, sex and eating have considerable commonality and are related in numerous ways.

The effect of a dopamine antagonist on conditioning of sexual arousal in women

RATIONALE

Dopamine (DA) plays a key role in reward-seeking behaviours. Accumulating evidence from animal and human studies suggests that human sexual reward learning may also depend on DA transmission. However, research on the role of DA in human sexual reward learning is completely lacking.

OBJECTIVES

To investigate whether DA antagonism attenuates classical conditioning of sexual response in humans.

METHODS

Healthy women were randomly allocated to one of two treatment conditions: haloperidol (n = 29) or placebo (n = 29). A differential conditioning paradigm was applied with genital vibrostimulation as unconditional stimulus (US) and neutral pictures as conditional stimuli (CSs). Genital arousal was assessed, and ratings of affective value and subjective sexual arousal were obtained.

RESULTS

Haloperidol administration affected unconditional genital responding. However, no significant effects of medication were found for conditioned responding.

CONCLUSIONS

No firm conclusions can be drawn about whether female sexual reward learning implicates DA transmission since the results do not lend themselves to unambiguous interpretation.

Unconscious Desire: The Affective and Motivational Aspects of Subliminal Sexual Priming

Sexual arousal is thought to be the result of the processing of sexual cues at two levels: conscious and unconscious. Whereas numerous studies have examined the affective and motivational responses to supraliminal (consciously processed) sexual cues, much less is known regarding the responses to subliminal (processed outside of one's awareness) sexual cues. Five studies examined responses to subliminal sexual cues. Studies 1–3 demonstrated increases in adults' positive affect following exposure to subliminal sexual cues compared to control cues. Study 4 demonstrated that the positive affect resulting from exposure to subliminal sexual cues increased motivation to further engage in a neutral task. Study 5 provided evidence suggesting that the affect and motivation found in Studies 1–4 were associated with motivation to engage in sex specifically, rather than a general approach motivation. The implications of these findings for the processing of subliminal sexual cues and for human sexuality are discussed.

Aberrant Topological Patterns of Structural Cortical Networks in Psychogenic Erectile Dysfunction

Male sexual arousal (SA) has been known as a multidimensional experience involving closely interrelated and coordinated neurobehavioral components that rely on widespread brain regions. Recent functional neuroimaging studies have shown relation between abnormal/altered dynamics in these circuits and male sexual dysfunction. However, alterations in the topological organization of structural brain networks in male sexual dysfunction are still unclear. Here, we used graph theory to investigate the topological properties of large-scale structural brain networks, which were constructed using inter-regional correlations of cortical thickness between 78 cortical regions in 40 patients with psychogenic erectile dysfunction (pED) and 39 normal controls. Compared with normal controls, pED patients exhibited a less optimal global topological organization with reduced global and increased local efficiencies. Our results suggest disrupted neural integration among distant brain regions in pED patients, consistent with previous reports of impaired white matter structure and abnormal functional integrity in pED. Additionally, disrupted global network topology in pED was observed to be primarily relevant to altered subnetwork and nodal properties within the networks mediating the cognitive, motivational and inhibitory processes of male SA, possibly indicating disrupted integration of these networks in the whole brain networks and might account for pED patients' abnormal cognitive, motivational and inhibitory processes for male SA. In total, our findings provide evidence for disrupted integrity in large-scale brain networks underlying the neurobehavioral processes of male SA in pED and provide new insights into the understanding of the pathophysiological mechanisms of pED.

Neural Substrates of Sexual Desire in Individuals with Problematic Hypersexual Behavior

Studies on the characteristics of individuals with hypersexual disorder have been accumulating due to increasing concerns about problematic hypersexual behavior (PHB). Currently, relatively little is known about the underlying behavioral and neural mechanisms of sexual desire. Our study aimed to investigate the neural correlates of sexual desire with event-related functional magnetic resonance imaging (fMRI). Twenty-three individuals with PHB and 22 age-matched healthy controls were scanned while they passively viewed sexual and nonsexual stimuli. The subjects' levels of sexual desire were assessed in response to each sexual stimulus. Relative to controls, individuals with PHB experienced more frequent and enhanced sexual desire during exposure to sexual stimuli. Greater activation was observed in the caudate nucleus, inferior parietal lobe, dorsal anterior cingulate gyrus, thalamus, and dorsolateral prefrontal cortex in the PHB group than in the control group. In addition, the hemodynamic patterns in the activated areas differed between the groups. Consistent with the findings of brain imaging studies of substance and behavior addiction, individuals with the behavioral characteristics of PHB and enhanced desire exhibited altered activation in the prefrontal cortex and subcortical regions. In conclusion, our results will help to characterize the behaviors and associated neural mechanisms of individuals with PHB.

Impact of Antidepressant Drugs on Sexual Function and Satisfaction

Pleasurable sexual activity is important in many human relationships and can provide a sense of physical, emotional and social well-being. Depressive symptoms and depressive illness are associated with impairments in sexual function and sexual dissatisfaction in untreated and treated patients. Most currently available antidepressant drugs are associated with development or worsening of sexual dysfunction in a substantial proportion of patients. Sexual difficulties during antidepressant treatment often resolve as depression lifts, but can persist over long periods, reducing self-esteem and affecting mood and relationships adversely. Sexual difficulties during antidepressant treatment typically have many possible causes but the incidence and nature of dysfunction varies between drugs. Many interventions can be considered when managing sexual dysfunction associated with antidepressants but no approach is 'ideal'. Because treatment-emergent sexual difficulties are less frequent with certain drugs, presumably related to differences in pharmacological properties, and since current interventions are suboptimal, a lower incidence of sexual dysfunction is a relevant tolerability target when developing novel antidepressants.

Managing temptation in obesity treatment: A neurobehavioral model of intervention strategies

Weight loss outcomes in lifestyle interventions for obesity are primarily a function of sustained adherence to a reduced-energy diet, and most lapses in diet adherence are precipitated by temptation from palatable food. The high nonresponse and relapse rates of lifestyle interventions suggest that current temptation management approaches may be insufficient for most participants. In this conceptual review, we discuss three neurobehavioral processes (attentional bias, temporal discounting, and the cold-hot empathy gap) that emerge during temptation and contribute to lapses in diet adherence. Characterizing the neurobehavioral profile of temptation highlights an important distinction between temptation resistance strategies aimed at overcoming temptation while it is experienced, and temptation prevention strategies that seek to avoid or minimize exposure to tempting stimuli. Many temptation resistance and temptation prevention strategies heavily rely on executive functions mediated by prefrontal systems that are prone to disruption by common occurrences such as stress, insufficient sleep, and even exposure to tempting stimuli. In contrast, commitment strategies are a set of devices that enable individuals to manage temptation by constraining their future choices, without placing heavy demands on executive functions. These concepts are synthesized in a conceptual model that categorizes temptation management approaches based on their intended effects on reward processing and degree of reliance on executive functions. We conclude by discussing the implications of our model for strengthening temptation management approaches in future lifestyle interventions, tailoring these approaches based on key individual difference variables, and suggesting high-priority topics for future research.

Animal Models for the Study of Female Sexual Dysfunction

INTRODUCTION

Significant progress has been made in elucidating the physiological and pharmacological mechanisms of female sexual function through preclinical animal research. The continued development of animal models is vital for the understanding and treatment of the many diverse disorders that occur in women.

AIM

To provide an updated review of the experimental models evaluating female sexual function that may be useful for clinical translation.

METHODS

Review of English written, peer-reviewed literature, primarily from 2000 to 2012, that described studies on female sexual behavior related to motivation, arousal, physiological monitoring of genital function and urogenital pain.

MAIN OUTCOMES MEASURES

Analysis of supporting evidence for the suitability of the animal model to provide measurable indices related to desire, arousal, reward, orgasm, and pelvic pain.

RESULTS

The development of female animal models has provided important insights in the peripheral and central processes regulating sexual function. Behavioral models of sexual desire, motivation, and reward are well developed. Central arousal and orgasmic responses are less well understood, compared with the physiological changes associated with genital arousal. Models of nociception are useful for replicating symptoms and identifying the neurobiological pathways involved. While in some cases translation to women correlates with the findings in animals, the requirement of circulating hormones for sexual receptivity in rodents and the multifactorial nature of women's sexual function requires better designed studies and careful analysis. The current models have studied sexual dysfunction or pelvic pain in isolation; combining these aspects would help to elucidate interactions of the pathophysiology of pain and sexual dysfunction.

CONCLUSIONS

Basic research in animals has been vital for understanding the anatomy, neurobiology, and physiological mechanisms underlying sexual function and urogenital pain. These models are important for understanding the etiology of female sexual function and for future development of pharmacological treatments for sexual dysfunctions with or without pain. Marson L, Giamberardino MA, Costantini R, Czakanski P, and Wesselmann U. Animal models for the study of female sexual dysfunction. Sex Med Rev 2013;1:108-122.

Implicit associations in cybersex addiction: Adaption of an Implicit Association Test with pornographic pictures

Recent studies show similarities between cybersex addiction and substance dependencies and argue to classify cybersex addiction as a behavioral addiction. In substance dependency, implicit associations are known to play a crucial role, and such implicit associations have not been studied in cybersex addiction, so far. In this experimental study, 128 heterosexual male participants completed an Implicit Association Test (IAT; Greenwald, McGhee, & Schwartz, 1998) modified with pornographic pictures. Further, problematic sexual behavior, sensitivity towards sexual excitation, tendencies towards cybersex addiction, and subjective craving due to watching pornographic pictures were assessed. Results show positive relationships between implicit associations of pornographic pictures with positive emotions and tendencies towards cybersex addiction, problematic sexual behavior, sensitivity towards sexual excitation as well as subjective craving. Moreover, a moderated regression analysis revealed that individuals who reported high subjective craving and showed positive implicit associations of pornographic pictures with positive emotions, particularly tended towards cybersex addiction. The findings suggest a potential role of positive implicit associations with pornographic pictures in the development and maintenance of cybersex addiction. Moreover, the results of the current study are comparable to findings from substance dependency research and emphasize analogies between cybersex addiction and substance dependencies or other behavioral addictions.

Neuroscience of Internet Pornography Addiction: A Review and Update

Many recognize that several behaviors potentially affecting the reward circuitry in human brains lead to a loss of control and other symptoms of addiction in at least some individuals. Regarding Internet addiction, neuroscientific research supports the assumption that underlying neural processes are similar to substance addiction. The American Psychiatric Association (APA) has recognized one such Internet related behavior, Internet gaming, as a potential addictive disorder warranting further study, in the 2013 revision of their Diagnostic and Statistical Manual. Other Internet related behaviors, e.g., Internet pornography use, were not covered. Within this review, we give a summary of the concepts proposed underlying addiction and give an overview about neuroscientific studies on Internet addiction and Internet gaming disorder. Moreover, we reviewed available neuroscientific literature on Internet pornography addiction and connect the results to the addiction model. The review leads to the conclusion that Internet pornography addiction fits into the addiction framework and shares similar basic mechanisms with substance addiction. Together with studies on Internet addiction and Internet Gaming Disorder we see strong evidence for considering addictive Internet behaviors as behavioral addiction. Future research needs to address whether or not there are specific differences between substance and behavioral addiction.

Measuring anhedonia: impaired ability to pursue, experience, and learn about reward

Ribot’s (1896) long standing definition of anhedonia as “the inability to experience pleasure” has been challenged recently following progress in affective neuroscience. In particular, accumulating evidence suggests that reward consists of multiple subcomponents of wanting, liking and learning, as initially outlined by Berridge and Robinson (2003), and these processes have been proposed to relate to appetitive, consummatory and satiety phases of a pleasure cycle. Building on this work, we recently proposed to reconceptualize anhedonia as “impairments in the ability to pursue, experience, and/or learn about pleasure, which is often, but not always accessible to conscious awareness.” (Rømer Thomsen et al., 2015). This framework is in line with Treadway and Zald’s (2011) proposal to differentiate between motivational and consummatory types of anhedonia, and stresses the need to combine traditional self-report measures with behavioral measures or procedures. In time, this approach may lead to improved clinical assessment and treatment. In line with our reconceptualization, increasing evidence suggests that reward processing deficits are not restricted to impaired hedonic impact in major psychiatric disorders. Successful translations of animal models have led to strong evidence of impairments in the ability to pursue and learn about reward in psychiatric disorders such as major depressive disorder, schizophrenia, and addiction. It is of high importance that we continue to systematically target impairments in all phases of reward processing across disorders using behavioral testing in combination with neuroimaging techniques. This in turn has implications for diagnosis and treatment, and is essential for the purposes of identifying the underlying neurobiological mechanisms. Here I review recent progress in the development and application of behavioral procedures that measure subcomponents of anhedonia across relevant patient groups, and discuss methodological caveats as well as implications for assessment and treatment.

Sexual Excitability and Dysfunctional Coping Determine Cybersex Addiction in Homosexual Males

Cybersex addiction (CA) has been mostly investigated in heterosexual males. Recent findings have demonstrated an association between CA severity and indicators of sexual excitability, and that coping by sexual behaviors mediated the relationship between sexual excitability and CA symptoms. The aim of this study was to test this mediation in a sample of homosexual males. Seventy-one homosexual males were surveyed online. Questionnaires assessed symptoms of CA, sensitivity to sexual excitation, pornography use motivation, problematic sexual behavior, psychological symptoms, and sexual behaviors in real life and online. Moreover, participants viewed pornographic videos and indicated their sexual arousal before and after the video presentation. Results showed strong correlations between CA symptoms and indicators of sexual arousal and sexual excitability, coping by sexual behaviors, and psychological symptoms. CA was not associated with offline sexual behaviors and weekly cybersex use time. Coping by sexual behaviors partially mediated the relationship between sexual excitability and CA. The results are comparable with those reported for heterosexual males and females in previous studies and are discussed against the background of theoretical assumptions of CA, which highlight the role of positive and negative reinforcement due to cybersex use.

Erotic subset for the Nencki Affective Picture System (NAPS ERO): cross-sexual comparison study

Research on the processing of sexual stimuli has proved that such material has high priority in human cognition. Yet, although sex differences in response to sexual stimuli were extensively discussed in the literature, sexual orientation was given relatively little consideration, and material suitable for relevant research is difficult to come by. With this in mind, we present a collection of 200 erotic images, accompanied by their self-report ratings of emotional valence and arousal by homo- and heterosexual males and females (n = 80, divided into four equal-sized subsamples). The collection complements the Nencki Affective Picture System (NAPS) and is intended to be used as stimulus material in experimental research. The erotic images are divided into five categories, depending on their content: opposite-sex couple (50), male couple (50), female couple (50), male (25) and female (25). Additional 100 control images from the NAPS depicting people in a non-erotic context were also used in the study. We showed that recipient sex and sexual orientation strongly influenced the evaluation of erotic content. Thus, comparisons of valence and arousal ratings in different subject groups will help researchers select stimuli set for the purpose of various experimental designs. To facilitate the use of the dataset, we provide an on-line tool, which allows the user to browse the images interactively and select proper stimuli on the basis of several parameters. The NAPS ERO image collection together with the data are available to the scientific community for non-commercial use at http://naps.nencki.gov.pl.

Commentary on: Are we overpathologizing everyday life? A tenable blueprint for behavioral addiction research. On functional and compulsive aspects of reinforcement pathologies

BACKGROUND

This paper is a commentary to a debate article entitled: "Are we overpathologizing everyday life? A tenable blueprint for behavioral addiction research", by Billieux et al. (2015). METHODS AND AIM: This brief response focused on the necessity to better characterize psychological and related neurocognitive determinants of persistent deleterious actions associated or not with substance utilization.

RESULTS

A majority of addicted people could be driven by psychological functional reasons to keep using drugs, gambling or buying despite the growing number of related negative consequences. In addition, a non-negligible proportion of them would need assistance to restore profound disturbances in basic learning processes involved in compulsive actions.

CONCLUSIONS

The distinction between psychological functionality and compulsive aspects of addictive behaviors should represent a big step towards more efficient treatments.

Central Somatosensory Networks Respond to a De Novo Innervated Penis: A Proof of Concept in Three Spina Bifida Patients

INTRODUCTION

Spina bifida (SB) causes low spinal lesions, and patients often have absent genital sensation and a highly impaired sex life. TOMAX (TO MAX-imize sensation, sexuality and quality of life) is a surgical procedure whereby the penis is newly innervated using a sensory nerve originally targeting the inguinal area. Most TOMAX-treated SB patients initially experience penile stimulation as inguinal sensation, but eventually, the perception shifts to penis sensation with erotic feelings. The brain mechanisms mediating this perceptual shift, which are completely unknown, could hold relevance for understanding the brain's role in sexual development.

AIM

The aim of this study was to study how a newly perceived penis would be mapped onto the brain after a lifelong disconnection.

METHODS

Three TOMAX-treated SB patients participated in a functional magnetic resonance imagery experiment while glans penis, inguinal area, and index finger were stimulated with a paint brush.

MAIN OUTCOME MEASURE

Brush stimulation-induced activation of the primary somatosensory cortex (SI) and functional connectivity between SI and remote cerebral regions.

RESULTS

Stimulation of the re-innervated side of the glans penis and the intact contralateral inguinal area activated a very similar location on SI. Yet, connectivity analysis identified distinct SI functional networks. In all three subjects, the middle cingulate cortex (MCC) and the parietal operculum-insular cortex (OIC) were functionally connected to SI activity during glans penis stimulation, but not to SI activity induced by inguinal stimulation.

CONCLUSIONS

Investigating central somatosensory network activity to a de novo innervated penis in SB patients is feasible and informative. The consistent involvement of MCC and OIC above and beyond the brain network expected on the basis of inguinal stimulation suggests that these areas mediate the novel penis sensation in these patients. The potential role of MCC and OIC in this process is discussed, along with recommendations for further research.

Structural insights into aberrant cortical morphometry and network organization in psychogenic erectile dysfunction

Functional neuroimaging studies have revealed abnormal brain dynamics of male sexual arousal (SA) in psychogenic erectile dysfunction (pED). However, the neuroanatomical correlates of pED are still unclear. In this work, we obtained cortical thickness (CTh) measurements from structural magnetic resonance images of 40 pED patients and 39 healthy control subjects. Abnormalities in CTh related to pED were explored using a scale space search based brain morphometric analysis. Organizations of brain structural covariance networks were analyzed as well. Compared with healthy men, pED patients showed significantly decreased CTh in widespread cortical regions, most of which were previously reported to show abnormal dynamics of male SA in pED, such as the medial prefrontal, orbitofrontal, cingulate, inferotemporal, and insular cortices. CTh reductions in these areas were found to be significantly correlated with male sexual functioning degradation. Moreover, pED patients showed decreased interregional CTh correlations from the right lateral orbitofrontal cortex to the right supramarginal gyrus and the left angular cortex, implying disassociations between the cognitive, motivational, and inhibitory networks of male SA in pED. This work provides structural insights on the complex phenomenon of psychogenic sexual dysfunction in men, and suggests a specific vulnerability factor, possibly as an extra "organic" factor, that may play an important role in pED.