Vaginal Pulse Amplitude Responses Research Articles

(058) Acute Dorsal Genital Neuromodulation can Improve Subjective Arousal: A Pilot Study in Women With and Without Spinal Cord Injury

Abstract Introduction Female sexual dysfunction (FSD) is a potentially life altering condition that impacts an estimated 40% of women. Unfortunately, the few treatment options available have limited success due to adverse events and an inability to improve subjective arousal. One potential treatment option, neuromodulation, has improved female sexual function index (FSFI) scores in small studies. The underlying mechanisms of how neuromodulation may improve FSD are not understood. We hypothesize that neuromodulation provides benefits by increasing genital blood flow. Objective Our primary objective is to determine if a single period of dorsal genital nerve stimulation (DGNS) or tibial nerve stimulation (TNS) directly causes a change in vaginal blood flow (VBF). Our secondary objective is to assess if subjective arousal increases during a single period of DGNS or TNS. These interventions will be compared among three cohorts of women: women with C6–T10 spinal cord injury (SCI), women with FSD (FSFI lubrication sub-score < 4), and able-bodied women without FSD. Methods Participants attended two separate visits, one for each nerve target, randomly ordered and separated by 1–5 months. We are testing two experimental paradigms: without and with erotic audio-visual materials. The first experiments measured vaginal pulse amplitude (VPA) using a vaginal photoplethysmography transducer (VPP) before, during, and after 20 minutes of nerve stimulation. After data processing, we calculated average peak to peak (p2p) amplitudes for each time period and performed an ANOVA and post-hoc pairwise comparisons within each participant. For the second experiment we measured VPA during neutral and erotic videos both without stimulation and with stimulation. In both experiments we measured subjective arousal via a Likert-type scale at 4 timepoints and made comparisons across participants with a paired t-test. The first experiments are complete and data collection for the second experiments is ongoing. Results We recruited three participants in each cohort in the first experiments, with five participants completing both sessions. All participants saw significant changes in their p2p amplitude from before stimulation to after stimulation in DGNS trials (n = 3 increased, n = 4 decreased). Three of five participants had significant p2p increases in TNS trials and one participant had significant decreases. DGNS subject arousal scores increased significantly after stimulation, but TNS scores did not (Figure 1). Most participants reported genital sensations during DGNS (7 of 8) and TNS (3 of 6) sessions. Three participants have completed both visits in the second set of experiments, with similar trends. Conclusions Acute DGNS, but not TNS, increased subjective arousal across all participants. VPA responses to stimulation were heterogeneous and although most changes were significant, there may not be physiological or clinical relevance. It is possible that repeated stimulation sessions over time may enhance changes in VPA. Disclosure No

Instructions to Rate Genital Vasocongestion Increases Genital and Self-Reported Sexual Arousal But Not Coherence Between Genital and Self-Reported Sexual Arousal

Women are often reported to have a low coherence (often referred to as "discordance" in sexuality literature) between their genital response and self-reported sexual arousal. The purpose of this study was to determine whether differing instructions for rating sexual arousal would increase the coherence between genital response and self-reported arousal in women. Genital responses were recorded, using vaginal photoplethysmography, from 32 young women while they fantasized in three different conditions. Conditions instructed women to rate their overall sexual arousal, any physical cues, and genital blood flow. The primary outcome measure was the coherence of vaginal pulse amplitude (VPA) and reported sexual response in the three conditions. Unexpectedly, both VPA response and self-reported sexual arousal were higher when women were asked to rate their genital blood flow. Examining only participants who reported at least some sexual arousal in all conditions (n = 17), coherence was highest when women were instructed to rate overall sexual arousal. Results suggest that focusing on genital blood flow during sexual fantasy may increase women's (self-reported and genital) sexual response. Focusing on any physical arousal cues during sexual fantasy was associated with lower coherence of women's genital response and self-reported arousal compared with when they were instructed to rate their overall sexual arousal.

The Sensitivity of Continuous Laboratory Measures of Physiological and Subjective Sexual Arousal for Diagnosing Women with Sexual Arousal Disorder

Past findings on the diagnostic sensitivity of vaginal photoplethysmography are limited by testing among women with heterogeneous sexual dysfunctions and by the use of statistical techniques that are unable to assess how changes in subjective arousal are associated with changes in physiological arousal. The aims of this study were to: (i) test the sensitivity of vaginal photoplethysmography and continuous measures of subjective sexual arousal in differentiating between women with and without sexual arousal or orgasm dysfunction; and (ii) examine the diagnostic utility of measuring the synchrony between genital and subjective sexual responses. Sexual arousal was assessed in sexually healthy women (n = 12), women with orgasm disorder (OD; n = 12), and 38 women who met the criteria for the three subcategories of sexual arousal dysfunction described by Basson et al. (i.e., genital sexual arousal disorder [GAD; n = 9], subjective sexual arousal disorder [SAD; n = 13], and combined genital and subjective arousal disorder [CAD; n = 16]). Physiological sexual arousal was assessed using vaginal photoplethysmography, and subjective sexual arousal was measured continuously and using a Likert-scale in response to sexual videos. Women with GAD showed the lowest and women with CAD showed the highest levels of vaginal pulse amplitude response to erotic stimuli. Women with sexual arousal disorder showed significantly lower levels of subjective sexual arousal to erotic stimuli than did sexually healthy women. Relations between subjective and physiological measures of sexual arousal were significantly weaker among women with sexual arousal disorder than sexually healthy women or women with OD. Preliminary support was provided for the diagnostic utility of measuring the synchrony between subjective and genital arousal in women with sexual arousal disorder. Findings do not support the sensitivity of using vaginal photoplethysmography, or continuous or Likert-scale measures of subjective arousal for differentiating between subtypes of women with sexual arousal disorder.

Measurement of Sexual Arousal in Postoperative Male-to-Female Transsexuals Using Vaginal Photoplethysmography

Men's sexual arousal patterns are category-specific: Men typically display significantly greater physiological responses to sexual stimuli depicting members of their preferred gender category. Category-specific patterns of sexual arousal have not been consistently reported in natal women. We used vaginal photoplethysmography to examine patterns of sexual arousal in 11 male-to-female (MtF) transsexuals following sex reassignment surgery (SRS) and in 72 natal women. Subjective arousal was measured with a continuous response lever. Video clips depicting sexual activity between two males, two females, or one male and one female were used as erotic stimuli. All transsexual participants displayed category-specific sexual arousal. Five homosexual transsexual participants (attracted exclusively to males before sex reassignment) showed greater genital and subjective responses to male than to female stimuli, while six nonhomosexual transsexual participants showed the opposite pattern. Vaginal pulse amplitude (VPA) was lower in transsexual participants than in natal women. The mean correlation between VPA and subjective responses was high in nonhomosexual transsexuals, but was significantly lower in homosexual transsexuals and in natal women. One transsexual participant who reported a change in sexual orientation following sex reassignment displayed VPA and subjective responses consistent with her pre-reassignment sexual orientation. We conclude that male-to-female transsexuals display male-typical category-specific sexual arousal following SRS, and that vaginal photoplethysmography is a promising methodology for studying patterns of sexual arousal in postoperative transsexuals.

Sexual psychophysiology and effects of sildenafil citrate in oestrogenised women with acquired genital arousal disorder and impaired orgasm: a randomised controlled trial

Some postmenopausal women lose genital sexual responsivity despite preserved subjective sexual arousal from non-genital stimuli. When oestrogen replacement is without benefit, both the underlying pathophysiology and management of this acquired genital female sexual arousal disorder are unclear. We aimed to study the effect of sildenafil on sexual arousal and orgasmic functioning of such women. Secondly, we aimed to explore the concordance between a detailed historical assessment of genital response in real life, with laboratory vaginal photoplethysmographic assessment of genital vasocongestion. Session one consisted of a semi-structured clinical interview to assess real life sexual arousal. Session two employed vaginal pulse amplitude and self-report questionnaire assessment of erotica-induced sexual arousal. Sessions three and four were a randomised, double-blind, placebo-controlled crossover administration of sildenafil on orgasm latency, intensity, perception of genital congestion and subjective arousal to erotica plus clitoral vibrostimulation. University associated Sexual Medicine Clinic and Psychophysiology Laboratory. Volunteer sample of 34 oestrogenised postmenopausal women with acquired genital female sexual arousal disorder and impaired orgasm. Sildenafil (50 mg) or placebo administered over two laboratory sessions. Orgasm latency and intensity during drug sessions; subjective and psychophysiological sexual arousal during photoplethysmography session. The erotic video significantly increased subjective sexual arousal in all women. Vaginal pulse amplitude responses varied from robust to absent. Although across all women, sildenafil improved neither arousal nor orgasm, subsequent analyses comparing high versus low vaginal pulse amplitude responders revealed significantly reduced latency to orgasm, and increased subjective sexual arousal and perception of genital arousal in the latter group of women. The data suggest that oestrogenised postmenopausal women with genital female sexual arousal disorder and orgasmic impairment based only on clinical assessment do not benefit from sildenafil. However, the photoplethysmograph had predictive value-those women showing low vaginal pulse amplitude response benefited from sildenafil compared with women with a higher response. Thus, oestrogenised women diagnosed with acquired genital female sexual arousal disorder may be a heterogeneous group and the photoplethysmograph might be useful in their further characterisation.

Acute Dehydroepiandrosterone Effects on Sexual Arousal in Premenopausal Women

The present investigation was designed to provide the first empirical examination of the effects of acute dehydroepiandrosterone (DHEA) administration on subjective and physiological sexual arousal in women. The primary purpose was to assess whether DHEA influences vaginal blood flow response in sexually functional women. Subjective (self-report) and physiological (vaginal photoplethysmograph) sexual responses to erotic stimuli were measured following DHEA (300 mg) and placebo administration in 12 sexually functional, premenopausal women, using a single-blind protocol. Acute DHEA significantly increased blood levels of dehydroepiandrosterone sulfate (DHEA-S) 30 min following drug administration but had no significant effect on either vaginal pulse amplitude responses or subjective responses to the erotic films. Acute DHEA does not appear to substantially influence sexual responding among sexually functional, premenopausal women.

Hormones and Sexuality in Postmenopausal Women: A Psychophysiological Study

Sexual function, including vaginal atrophy, and hormonal status, were studied in 42 naturally postmenopausal women. Vaginal pulse amplitude and subjective sexual responses during self-induced erotic fantasy and during erotic films were compared with responses of a small number of premenopausal women. As predicted, vaginal atrophy was related to estrogens but not to complaints of vaginal dryness and dyspareunia. No significant relationship was found between hormones and sexual function. Unexpectedly, most of the few correlations that did reach significance involved prolactin. The fact that prolactin was negatively associated with sexual desire, sexual arousal and vaginal lubrication during sexual activity, suggests that psychosocial factors are more important titan hormone levels in postmenopausal sexual function. Comparisons with a number of premenopausal women revealed that although postmenopausal women displayed lower vaginal pulse amplitude responses prior to erotic stimulation than the premenopausal women, this difference disappeared during subsequent erotic stimulation. We argued that this finding can be interpreted as being supportive of the notion that complaints of vaginal dryness and dyspareunia should not be attributed to vaginal atrophy associated with menopause. Rather, vaginal dryness and dyspareunia seem to reflect sexual arousal problems.

The effects of sympathetic activation on physiological and subjective sexual arousal in women

This investigation was designed to examine the effects of acute exercise on physiological and subjective sexual arousal in women. In Experiment 1, Ss participated in two experimental sessions in which they viewed a neutral film followed by an erotic film. In one of these sessions, Ss were exposed to 20 min of intense exercise prior to viewing the films. Subjective sexual arousal was measured with a self-report rating scale and physiological sexual arousal was measured with a vaginal photoplethysmograph. Acute exercise significantly decreased vaginal pulse amplitude responses to a neutral stimulus and significantly increased vaginal pulse amplitude responses to an erotic stimulus. Exercise marginally increased vaginal blood volume responses to an erotic film but had no significant effect on subjective perceptions of sexual arousal. In Experiment 2, Ss viewed two consecutive neutral stimuli preceded by 20 min of intense exercise. There were no significant differences in either vaginal blood volume or vaginal pulse amplitude between the two neutral films. Together, the data from Experiments 1 and 2 provide indirect support for a facilitatory role of sympathetic activation in female sexual arousal.

Vaginal pulse amplitude response patterns during erotic conditions and sleep.

Vaginal photoplethysmography has been used to investigate sexual arousal response patterns in small samples of sexually functional and dysfunctional women, but selection of subjects for these studies has not been of a standardized nature. In the present study, two groups of women, who placed in either the upper or lower percentile ranks on the Sexual Arousal Inventory (Hoon et al., 1976a), were compared on a physiological measure of sexual arousal, vaginal pulse amplitude (VPA), during both waking erotic conditions and sleep. As hypothesized, no differences in VPA were found between groups during either waking or sleeping conditions. Contrary to expectation, groups also did not differ on subjective ratings of their laboratory arousal. With both groups combined, differences in VPA levels were evident between baseline and erotic conditions. Similarly, VPA levels differed between stages of sleep, with highest levels observed during rapid-eye-movement (REM) sleep. These findings suggest that self-reported low arousability is not based on lack of physiological response and that retrospective, self-report measures of sexual arousability differ in important ways from subjective and physiological measures of sexual arousal in the laboratory. In order to adequately assess sexual arousability, future researchers must either devise laboratory conditions that more closely resemble erotic stimuli occurring in subjects' natural environments or validate physiological measures of arousal in nonlaboratory settings. Finally, the nocturnal evaluation of VPA seems potentially useful for cases in which organic factors may be contributing to sexual dysfunction.

Female sexual response patterns. Interactions of physiological, affective, and contextual cues.

This study examined physiological, affective, and contextual components of female sexual responsiveness and satisfaction. Fifty-five women, aged 21 to 58, 27 of whom were married participated in two psychophysiological laboratory sessions and completed a questionnaire. During each laboratory session, physiological and self-reported sexual arousal were measured in response to an erotic tape, film, and self-generated fantasies. Vaginal pulse amplitude responses showed married women to be less aroused to erotic materials during session 1 but not session 2. Self-reported sexual arousal was correlated with vaginal response only in the unmarried sample and only during the tape and film of session 1. Subjectively reported sexual arousal was also correlated with a constellation of positive affective states. Generally, negative correlations were found between vaginal response in the laboratory and reported sexual responsiveness at home. The patterning of the affective-physiological relationships suggests several interpretations with regard to female sexuality and models to human emotion.