Associations Between Sexual Function and Disordered Eating Among Undergraduate Women: An Emphasis on Sexual Pain and Distress.

The limited body of research on sexuality in eating disorders supports the occurrence of considerable sexual concerns. The aim of the present study was to examine eating disorder symptoms in relation to sexual function, and sexual pain in particular. Female undergraduate students completed a series of online questionnaires. All domains of sexual function were predicted by aspects of disordered eating, with disordered eating generally being associated with more sexual difficulties. Psychological characteristics common to those with eating pathology were also associated with sexuality variables, such that psychological maladjustment was associated with poorer sexual function. Psychological maladjustment was found to mediate the association between eating disorder risk and sexual function. The results of this study suggest that sexual function should be addressed during eating disorder care.

Dual Control Model in a Cross-Cultural Context: Role of Sexual Excitation in Sexual Response and Behavior Differences Between Chinese and Euro-Caucasian Women in Canada.

Chinese women in Western nations frequently report less engagement with sexuality, such as lower sexual response and behaviors, and more restrictive sexual attitudes, than their Euro-Caucasian peers. This difference is likely related to sexual conservatism within traditional Chinese culture, though the mechanisms underlying how culture influences sexual responding are not well understood. The current study investigated if these differences were consistent with the dual control model, a well-established model for understanding regulation of sexual response. Chinese and Euro-Caucasian women (N = 471; age M = 20.7 years, SD = 3.3) residing in Canada from a university sample completed self-report questionnaires on sexual excitation and inhibition, sexual attitudes, and various sexual response and behavior measures. Sexual excitation was significantly lower in Chinese than Euro-Caucasian women and was significantly associated with sexual response in both groups. Structural equation modeling showed that sexual response variables were associated with a latent sexual excitation factor and that sexual attitudes partially mediated the relationship between this latent factor and ethnicity. The findings showed that sexual excitation and sexual attitudes contribute to cross-cultural differences in women's sexual responding. Theoretical and clinical considerations are discussed.

Sexual Fantasy and Masturbation Among Asexual Individuals: An In-Depth Exploration.

Human asexuality is generally defined as a lack of sexual attraction. We used online questionnaires to investigate reasons for masturbation, and explored and compared the contents of sexual fantasies of asexual individuals (identified using the Asexual Identification Scale) with those of sexual individuals. A total of 351 asexual participants (292 women, 59 men) and 388 sexual participants (221 women, 167 men) participated. Asexual women were significantly less likely to masturbate than sexual women, sexual men, and asexual men. Asexual women were less likely to report masturbating for sexual pleasure or fun than their sexual counterparts, and asexual men were less likely to report masturbating for sexual pleasure than sexual men. Both asexual women and men were significantly more likely than sexual women and men to report that they had never had a sexual fantasy. Of those who have had a sexual fantasy, asexual women and men were significantly more likely to endorse the response "my fantasies do not involve other people" compared to sexual participants, and consistently scored each sexual fantasy on a questionnaire as being less sexually exciting than did sexual participants. When using an open-ended format, asexual participants were more likely to report having fantasies about sexual activities that did not involve themselves, and were less likely to fantasize about topics such as group sex, public sex, and having an affair. Interestingly, there was a large amount of overlap between sexual fantasies of asexual and sexual participants. Notably, both asexual and sexual participants (both men and women) were equally likely to fantasize about topics such as fetishes and BDSM.

Sexual Functioning in Young Women and Men: Role of Attachment Orientation.

Prior research has documented various ways in which adult attachment styles are characteristic of differential behavioral and cognitive patterns within romantic relationships and sexuality. However, few studies have examined the direct influence of anxious or avoidant attachment orientation on sexual function. The aim of the present study was to assess the impact of insecure attachment on sexual function. Undergraduate students completed questionnaires measuring attachment style and sexual functioning. Among women, attachment avoidance tended to be associated with impairments in all aspects of sexual function, whereas anxious attachment tended to be associated with declines in arousal, satisfaction, and ability to achieve orgasm. A different trend was seen in men: Anxious attachment tended to be associated with multiple facets of sexual dysfunction, while avoidant attachment did not correlate with any sexual function deficits and was associated with superior physiological competence. These results suggest that both anxious and avoidant attachment styles are important yet differential predictors of sexual function in men and women.

Evidence for a Role of Adolescent Endocannabinoid Signaling in Regulating HPA Axis Stress Responsivity and Emotional Behavior Development.

Adolescence is a period characterized by many distinct physical, behavioral, and neural changes during the transition from child- to adulthood. In particular, adolescent neural changes often confer greater plasticity and flexibility, yet with this comes the potential for heightened vulnerability to external perturbations such as stress exposure or recreational drug use. There is substantial evidence to suggest that factors such as adolescent stress exposure have longer lasting and sometimes more deleterious effects on an organism than stress exposure during adulthood. Moreover, the adolescent neuroendocrine response to stress exposure is different from that of adults, suggesting that further maturation of the adolescent hypothalamic-pituitary-adrenal (HPA) axis is required. The endocannabinoid (eCB) system is a potential candidate underlying these age-dependent differences given that it is an important regulator of the adult HPA axis and neuronal development. Therefore, this review will focus on (1) the functionality of the adolescent HPA axis, (2) eCB regulation of the adult HPA axis, (3) dynamic changes in eCB signaling during the adolescent period, (4) the effects of adolescent stress exposure on the eCB system, and (5) modulation of HPA axis activity and emotional behavior by adolescent cannabinoid treatment. Collectively, the emerging picture suggests that the eCB system mediates interactions between HPA axis stress responsivity, emotionality, and maturational stage. These findings may be particularly relevant to our understanding of the development of affective disorders and the risks of adolescent cannabis consumption on emotional health and stress responsivity.

Insecure Attachment Style and Dysfunctional Sexual Beliefs Predict Sexual Coercion Proclivity in University Men.

INTRODUCTION: Past studies have shown an association between low sexual functioning and engaging in sexually coercive behaviors among men. The mechanism of this relationship is not well understood. Moreover, most studies in this area have been done in incarcerated sex offenders. AIMS: The aim of the current study was to investigate the role of potential distal predictors of sexual coercion, including insecure attachment style and dysfunctional sexual beliefs, in mediating the relationship between sexual functioning and sexual coercion. The study also seeks to extend past findings to a novel non-forensic population. METHODS: Male university students (N = 367) anonymously completed online questionnaires. MAIN OUTCOME MEASURES: Participants completed the Sexual Experiences Survey, Improved Illinois Rape Myth Acceptance Scale, Hostility Towards Women Scale, Likelihood of Rape Item, Experiences in Close Relationships Scale, Dysfunctional Sexual Beliefs Scale, and Brief Sexual Functioning Questionnaire. RESULTS: Sexual functioning was not significantly associated with sexually coercive behaviors in our sample (r = 0.08, P = 0.247), though a significant correlation between sexual functioning and rape myth acceptance was found (r = 0.18, P = 0.007). Path analysis of all variables showed that the likelihood of rape item was the strongest correlate of sexually coercive behaviors (ß = 0.34, P < 0.001), while dysfunctional sexual beliefs appeared to mediate the association between anxious attachment and likelihood of rape item score. Anxious (r = -0.27, P = 0.001) and avoidant (r = -0.19, P = 0.004) attachment also correlated significantly with lower sexual functioning. CONCLUSIONS: These findings suggest the relationship between sexual functioning and sexual coercion may be less robust than previously reported, and may be due to a shared association with other factors. The results elaborate on the interrelation between attachment style and dysfunctional sexual beliefs as predictors of sexual coercion proclivity, suggesting avenues for further research.

Disruption of peri-adolescent endocannabinoid signaling modulates adult neuroendocrine and behavioral responses to stress in male rats.

The endocannabinoid (eCB) system is known to regulate neural, endocrine and behavioral responses to stress in adults; however there is little knowledge regarding how this system governs the development and maturation of these responses. Previous work has reported dynamic and time-specific changes in CB1 receptor expression, N-arachidonylethanolamine (AEA) content and fatty acid amide hydrolase (FAAH) activity within corticolimbic structures throughout the peri-adolescent period. To examine whether fluctuations in adolescent eCB activity contribute to the development of adult stress responsivity and emotionality, we treated male Sprague-Dawley rats daily with the CB1R antagonist, AM-251 (5 mg/kg), or vehicle between post-natal days (PND) 35-45. Following this treatment, emotional behavior, HPA axis stress reactivity and habituation to repeated restraint stress, as well as corticolimbic eCB content were examined in adulthood (PND 75). Behaviorally, AM-251-treated males exhibited more active stress-coping behavior in the forced swim test, greater risk assessment behavior in the elevated plus maze and no significant differences in general motor activity. Peri-adolescent AM-251 treatment modified corticosterone habituation to repeated restraint exposure compared to vehicle. Peri-adolescent CB1R antagonism induced moderate changes in adult corticolimbic eCB signaling, with a significant decrease in amygdalar AEA, an increase in hypothalamic AEA and an increase in prefrontal cortical CB1R expression. Together, these data indicate that peri-adolescent endocannabinoid signaling contributes to the maturation of adult neurobehavioral responses to stress.

Role of Partner Novelty in Sexual Functioning: A Review.

This review investigates whether sexual desire and arousal decline in response to partner familiarity, increase in response to partner novelty, and show differential responding in men and women. These questions were considered through the perspective of two leading evolutionary theories regarding human mating strategies: sexual strategies theory and attachment fertility theory. The hypotheses emerging from these theories were evaluated through a critical analysis of several areas of research including habituation of arousal to erotic stimuli, preferences regarding number of sexual partners, the effect of long-term monogamous relationships on sexual arousal and desire, and prevalence and risk factors associated with extradyadic behavior. The current literature best supports the predictions made by sexual strategies theory in that sexual functioning has evolved to promote short-term mating. Sexual arousal and desire appear to decrease in response to partner familiarity and increase in response to partner novelty in men and women. Evidence to date suggests this effect may be greater in men.

A validated measure of no sexual attraction: the Asexuality Identification Scale.

Human asexuality has been described as a lack of sexual attraction toward anyone or anything. One percent of the adult population is thought to be asexual, and research suggests that asexuality is best conceptualized as a sexual orientation. A serious limitation in past research on asexuality has been the complete lack of a validated tool to measure asexuality. Due to limitations in recruiting sufficiently powered local samples, most studies have relied on recruiting via online web-based asexual communities. This is problematic because it limits the sample to individuals who have been recruited through established asexuality networks/communities. The present study aimed to develop and validate a self-report questionnaire to assess asexuality. The questionnaire was intended to provide a valid measure independent of whether the individual self-identified as asexual and was developed in several stages, including: development and administration of open-ended questions (209 participants: 139 asexual and 70 sexual); administration and analysis of resulting 111 items (917 participants: 165 asexual and 752 sexual); administration and analysis of 37 retained items (1,242 participants: 316 asexual and 926 sexual); and validity analysis of the final items. The resulting Asexuality Identification Scale (AIS), a 12-item questionnaire, is a brief, valid, and reliable self-report instrument for assessing asexuality. It is psychometrically sound, easy to administer, and has demonstrated ability to discriminate between sexual and asexual individuals. It should prove useful to allow researchers to recruit more representative samples of the asexual population, permitting for an increased understanding of asexuality.

Asexuality: an extreme variant of sexual desire disorder?

INTRODUCTION: Human asexuality is defined as a lack of sexual attraction to anyone or anything. Various theories have been proposed to explain how asexuality should best be classified, and some have maintained that asexuality is an extreme variant of hypoactive sexual desire disorder (HSDD)-a sexual dysfunction characterized by a lack of interest in sex and significant distress. To date, this has never been empirically examined. AIM AND METHOD: Using measures of sexual desire and behavior, sex-related distress, personality, and psychopathology, the aim of the current study was to compare individuals scoring above the cutoff for asexuality identification (AIS >40) (n = 192) to sexual individuals (n = 231). The sexual group was further divided into a control group (n = 122), a HSDD group (n = 50), and a group with symptoms of low desire that were nondistressing (n = 59). RESULTS: Analyses were controlled for age. Individuals in the AIS >40 group had a greater likelihood of never previously engaging in sexual intercourse, fantasies, or kissing and petting than all other groups and a lower likelihood of experiencing sex-related distress than those with HSDD. For women, those in the HSDD and AIS >40 groups had significantly lower desire than the subclinical HSDD and control groups. Men in the AIS >40 group had significantly lower desire than the other three groups. Symptoms of depression were highest among those with subclinical HSDD and HSDD, whereas there were no group differences on alexithymia or desirable responding. A binary logistic regression indicated that relationship status (long-term dating/married), sexual desire, sex-related distress, and lower alexithymia scores were the best predictors of group membership (HSDD vs. AIS >40). CONCLUSION: Taken together, these results challenge the speculation that asexuality should be classified as a sexual dysfunction of low desire.

A critical role for prefrontocortical endocannabinoid signaling in the regulation of stress and emotional behavior.

The prefrontal cortex (PFC) provides executive control of the brain in humans and rodents, coordinating cognitive, emotional, and behavioral responses to threatening stimuli and subsequent feedback inhibition of the hypothalamic-pituitary-adrenal (HPA) axis. The endocannabinoid system has emerged as a fundamental regulator of HPA axis feedback inhibition and an important modulator of emotional behavior. However, the precise role of endocannabinoid signaling within the PFC with respect to stress coping and emotionality has only recently been investigated. This review discusses the current state of knowledge regarding the localization and function of the endocannabinoid system in the PFC, its sensitivity to stress and its role in modulating the neuroendocrine and behavioral responses to aversive stimuli. We propose a model whereby steady-state endocannabinoid signaling in the medial PFC indirectly regulates the outflow of pyramidal neurons by fine-tuning GABAergic inhibition. Local activation of this population of CB1 receptors increases the downstream targets of medial PFC activation, which include inhibitory interneurons in the basolateral amygdala, inhibitory relay neurons in the bed nucleus of the stria terminalis and monoamine cell bodies such as the dorsal raphe nucleus. This ultimately produces beneficial effects on emotionality (active coping responses to stress and reduced anxiety) and assists in constraining activation of the HPA axis. Under conditions of chronic stress, or in individuals suffering from mood disorders, this system may be uniquely recruited to help maintain appropriate function in the face of adversity, while breakdown of the endocannabinoid system in the medial PFC may be, in and of itself, sufficient to produce neuropsychiatric illness. Thus, we suggest that endocannabinoid signaling in the medial PFC may represent an attractive target for the treatment of stress-related disorders.

Biological markers of asexuality: Handedness, birth order, and finger length ratios in self-identified asexual men and women.

Human asexuality is defined as a lack of sexual attraction to anyone or anything and it has been suggested that it may be best conceptualized as a sexual orientation. Non-right-handedness, fraternal birth order, and finger length ratio (2D:4D) are early neurodevelopmental markers associated with sexual orientation. We conducted an Internet study investigating the relationship between self-identification as asexual, handedness, number of older siblings, and self-measured finger-lengths in comparison to individuals of other sexual orientation groups. A total of 325 asexuals (60 men and 265 women; M age, 24.8 years), 690 heterosexuals (190 men and 500 women; M age, 23.5 years), and 268 non-heterosexuals (homosexual and bisexual; 64 men and 204 women; M age, 29.0 years) completed online questionnaires. Asexual men and women were 2.4 and 2.5 times, respectively, more likely to be non-right-handed than their heterosexual counterparts and there were significant differences between sexual orientation groups in number of older brothers and older sisters, and this depended on handedness. Asexual and non-heterosexual men were more likely to be later-born than heterosexual men, and asexual women were more likely to be earlier-born than non-heterosexual women. We found no significant differences between sexual orientation groups on measurements of 2D:4D ratio. This is one of the first studies to test and provide preliminary empirical support for an underlying neurodevelopmental basis to account for the lack of sexual attraction characteristic of asexuality.

Sex, drugs, and adult neurogenesis: sex-dependent effects of escalating adolescent cannabinoid exposure on adult hippocampal neurogenesis, stress reactivity, and amphetamine sensitization.

Cannabinoid exposure during adolescence has adverse effects on neuroplasticity, emotional behavior, cognition, and reward sensitivity in adult rats. We investigated whether escalating doses of the cannabinoid receptor 1 (CB1 R) agonist, HU-210, in adolescence would affect adult hippocampal neurogenesis and behavioral processes putatively modulated by hippocampal neurogenesis, in adult male and female Sprague-Dawley rats. Escalating doses of HU-210 (25, 50, and 100 µg/kg), or vehicle were administered from postnatal day (PND) 35 to 46. Animals were left undisturbed until PND 70, when they were treated with 5-bromo-2-deoxyuridine (BrdU; 200 mg/kg) and perfused 21 days later to examine density of BrdU-ir and BrdU/NeuN cells in the dentate gyrus. In another cohort, hypothalamic-pituitary-adrenal (HPA) axis reactivity to an acute restraint stress (30 min; PND 75) and behavioral sensitization to d-amphetamine sulfate (1-2 mg/kg; PND 105-134) were assessed in adulthood. Adolescent HU-210 administration suppressed the density of BrdU-ir cells in the dentate gyrus in adult male, but not adult female rats. Adolescent HU-210 administration also induced significantly higher peak corticosterone levels and reminiscent of the changes in neurogenesis, this effect was more pronounced in adult males than females. However, adolescent cannabinoid treatment resulted in significantly higher stereotypy scores in adult female, but not male, rats. Thus, adolescent CB1 R activation suppressed hippocampal neurogenesis and increased stress responsivity in adult males, but not females, and enhanced amphetamine sensitization in adult female, but not male, rats. Taken together, increased CB1 R activation during adolescence results in sex-dependent, long-term, changes to hippocampal structure and function, an effect that may shed light on differing vulnerabilities to developing disorders following adolescent cannabinoid exposure, based on sex.

Cognitive aspects of sexual functioning: differences between East Asian-Canadian and Euro-Canadian women.

The purpose of this study was to investigate the sexual beliefs of female undergraduates, as well as the thoughts they experience during sexual experiences. The study aimed to determine potential differences in these variables between East Asian-Canadians and Euro-Canadians, as well as the influence of acculturation on these variables. In addition, the relationships between sexual beliefs, automatic thoughts, and specific aspects of sexual functioning were examined. Euro-Canadian (n = 77) and East Asian-Canadian (n = 123) undergraduate women completed the Sexual Dysfunctional Beliefs Questionnaire, the Sexual Modes Questionnaire, the Female Sexual Function Index, and the Vancouver Index of Acculturation. East Asian women endorsed almost all sexual beliefs assessed in this study more than did Euro-Canadian women, and endorsement of these beliefs was associated with acculturation. In addition, East Asian-Canadian and Euro-Canadian women differed in the frequency of experiencing negative automatic thoughts. Results also revealed associations between difficulties in sexual functioning, and both sexual beliefs and automatic thoughts. Together, these results provide preliminary support for the hypothesis that differences in cognitive aspects of sexuality may underlie the differences in sexual functioning previously observed between these two groups.

Perceived prevalence and definitions of sexual dysfunction as predictors of sexual function and satisfaction.

Evidence for the influence of sexual beliefs on sexual functioning and satisfaction has mainly emanated from clinical lore. Empirical investigations on this topic remain sparse. This study investigated whether beliefs regarding prevalence and definitions of male and female sexual dysfunctions predicted sexual function and satisfaction in a sample of 131 undergraduate students. Results indicated that higher perceived prevalence of male and female sexual dysfunctions was predictive of lower sexual functioning and poorer sexual satisfaction in women. For the male participants, none of the examined sexual beliefs emerged as significant predictors of their sexual functioning or satisfaction. Surprisingly, it was also found that participants estimated the prevalence of female sexual dysfunctions to be higher than male sexual dysfunctions, while defining male sexual dysfunctions more broadly than female sexual dysfunctions. Possible mechanisms for the findings are provided.

Effect of sexual coercion proclivity and cognitive priming on sexual aggression in the laboratory.

This research follows from the "rape proclivity" literature to evaluate whether proclivity actually predicts sexual coercion. One hundred forty-two heterosexual males attending a Canadian university participated. Participants completed the sexual coercion proclivity questionnaire packet to determine high or low sexual coercion proclivity, and were randomly assigned to complete either an innocuous or a sexually aggressive cognitive priming task. Sexual coercion was operationalized by having men read increasingly graphic sexual material to an increasingly uncomfortable confederate. Regardless of condition, high sexual coercion proclivity males were more likely to engage in sexual coercion than low sexual coercion proclivity males. When the effects of discomfort were controlled, a significant interaction emerged between sexual coercion proclivity and the priming condition on sexual coercion. Although engaging in significantly less sexual coercion than the high sexual coercion proclivity males when assigned to the innocuous cognitive priming task, the low sexual coercion proclivity males assigned to the sexually aggressive cognitive priming task were indistinguishable from the high sexual coercion proclivity group. The nature of this relationship differed for Caucasian and Chinese men. These findings suggest that even those not previously inclined toward sexual coercion can do so under opportunistic circumstances, following an increase in discomfort associated with exposure to and involvement with sexually aggressive material. The prevention implications associated with this are discussed.

Temporal changes in N-acylethanolamine content and metabolism throughout the peri-adolescent period.

Fatty acid amide hydrolase (FAAH) regulates tissue concentrations of N-acylethanolamines (NAEs), including the endocannabinoid, N-arachidonylethanolamide (anandamide, AEA). FAAH activity and NAEs are widely distributed throughout the brain and FAAH activity regulates an array of processes including emotion, cognition, inflammation, and feeding. However, there is relatively little research describing how this system develops throughout adolescence, particularly within limbic circuits regulating stress and reward processing. Thus, this study characterized temporal changes in NAE content (AEA, oleoylethanolamine [OEA], and palmitoylethanolamide [PEA]) and FAAH activity across the peri-adolescent period, in four corticolimbic structures (amygdala, hippocampus, prefrontal cortex, and hypothalamus). Brain tissue of male Sprague-Dawley rats was collected on postnatal days (PND) 25, 35, 45, and 70, representing pre-adolescence, early- to mid-adolescence, late adolescence, and adulthood, respectively. Tissue was analyzed for AEA, OEA, and PEA content as well as FAAH activity at each time point. AEA, OEA, and PEA exhibited a similar temporal pattern in all four brain regions. NAE concentrations were lowest at PND 25 and highest at PND 35. NAE concentrations decreased between PNDs 35 and 45 and increased between PNDs 45 and 70. FAAH activity mirrored the pattern of NAE content in which it decreased between PNDs 25 and 35, increased between PNDs 35 and 45, and decreased between PNDs 45 and 70. These age-dependent patterns of NAE content and FAAH activity demonstrate temporal specificity to the development of this system and could contribute to alterations in stress sensitivity, emotionality, and executive function which also fluctuate during this developmental period.

Effect of sexual coercion proclivity, insult and fantasy on emotional reactivity and appeal of sexual aggression.

Fifty-nine heterosexual university males were assessed for Sexual Coercion Proclivity (SCP) and randomly assigned to one of three conditions: Insult/nonsexually coercive fantasy material; no insult/sexually coercive fantasy material; or, insult/sexually coercive fantasy material. Although not differing in terms of anger or anxiety, the high SCP became more frustrated than the low group, particularly when exposed to both insult and sexually coercive (SC) fantasy material. Changes in negative affect predicted anticipated likelihood of engaging in SC among the low SCP group and anticipated enjoyment of SC in the high SCP group. Acculturation accounted for differences observed between Caucasian and Chinese men.

Neurobiology of chronic mild stress: parallels to major depression.

The chronic mild (or unpredictable/variable) stress (CMS) model was developed as an animal model of depression more than 20 years ago. The foundation of this model was that following long-term exposure to a series of mild, but unpredictable stressors, animals would develop a state of impaired reward salience that was akin to the anhedonia observed in major depressive disorder. In the time since its inception, this model has also been used for a variety of studies examining neurobiological variables that are associated with depression, despite the fact that this model has never been critically examined to validate that the neurobiological changes induced by CMS are parallel to those documented in depressive disorder. The aim of the current review is to summarize the current state of knowledge regarding the effects of chronic mild stress on neurobiological variables, such as neurochemistry, neurochemical receptor expression and functionality, neurotrophin expression and cellular plasticity. These findings are then compared to those of clinical research examining common variables in populations with depressive disorders to determine if the changes observed following chronic mild stress are in fact consistent with those observed in major depression. We conclude that the chronic mild stress paradigm: (1) evokes an array of neurobiological changes that mirror those seen in depressive disorders and (2) may be a suitable tool to investigate novel systems that could be disturbed in depression, and thus aid in the development of novel targets for the treatment of depression.

Circulating endocannabinoid concentrations and sexual arousal in women.

INTRODUCTION: Several lines of evidence point to the potential role of the endocannabinoid system in female sexual functioning. These include results from studies describing the subjective effects of exogenous cannabinoids on sexual functioning in humans and the observable effects of exogenous cannabinoids on sexual functioning in other species, as well as results from studies investigating the location of cannabinoid receptors in the brain and periphery, and the effects of cannabinoid receptor activation on neurotransmitters implicated in sexual functioning. While these lines of research suggest a role for the endocannabinoid system in female sexual functioning, no studies investigating the relationship between concentrations of endogenous cannabinoids (i.e., arachidonoylethanolamide [AEA] and 2-arachidonoylglycerol [2-AG]) and sexual functioning have been conducted in any species. AIM: To measure circulating endocannabinoid concentrations in relation to subjective and physiological indices of sexual arousal in women (N = 21). METHODS: Serum endocannabinoid (AEA and 2-AG) concentrations were measured immediately prior to, and immediately following, viewing of neutral (control) and erotic (experimental) film stimuli in a repeated measures design. Physiological sexual arousal was measured via vaginal photoplethysmography. Subjective sexual arousal was measured both continuously and noncontinuously. Pearson's correlations were used to investigate the relationships between endocannabinoid concentrations and sexual arousal. MAIN OUTCOME MEASURES: Changes in AEA and 2-AG concentrations from pre- to post-film and in relation to physiological and subjective indices of sexual arousal. RESULTS: Results revealed a significant relationship between endocannabinoid concentrations and female sexual arousal, whereby increases in both physiological and subjective indices of sexual arousal were significantly associated with decreases in AEA, and increases in subjective indices of sexual arousal were significantly associated with decreases in 2-AG. CONCLUSIONS: These findings support the hypothesis that the endocannabinoid system is involved in female sexual functioning, with implications for furthering understanding of the biological mechanisms underlying female sexual functioning.