Exploring Comfort Levels and the Role of Compensation in Sexual Psychophysiology Study Participation

Does the Paraphilia Scale Work for Everyone? Confirmatory Factor Analysis and Measurement Invariance Across Gender and Sexual Orientation Groups

We conducted three studies to examine the factor structure and measurement invariance of the Paraphilia Scale, a measure of paraphilic interests used in multiple studies. In the first study, we conducted a confirmatory factor analysis (CFA) testing different a priori models with a community sample of 1,040 adults previously reported by Seto et al. (2021), and found support for a hierarchical four-factor model: An agonistic continuum involving coercion or physical pain (biastophilia, sexual sadism, masochism), chronophilias (pedophilia, hebephilia), courtship disorders (voyeurism, exhibitionism, and frotteurism), and fetishism (object fetishism, transvestic fetishism, urophilia-coprophilia). This factor structure was replicated in a second study comprising a combined sample of 400 mTurk participants and 870 university students. The third study analyzed the community sample and found evidence of configural invariance but not scalar or metric invariance across gender (man or woman) and sexual orientation for gender (heterosexual or other sexual orientation). This indicates that the factor structure of the Paraphilia Scale is robust for gender and sexual orientation for gender, but factor loadings differ across these groups, as do the loadings of individual items on the four factors. Implications for research on gender and sexual orientation differences in paraphilic interests are discussed.

Use of sexual stimuli in research and clinical settings: expert opinion and recommendations

Background

Sexual stimuli, such as sexual videos, images, and narratives describing sexual interactions, are one of many tools used by clinicians and researchers to elicit or augment sexual response. Given the wide variability within sexual stimuli and their effects on sexual response, we provide guidance on when and how to use sexual stimuli, selecting sexual stimuli, and standardizing the use and reporting of sexual stimuli in research and clinical practice.

Aim

This expert opinion review article discusses standard operating procedures when using sexual stimuli in clinical and research applications, addressing 3 broad areas: settings in which sexual stimuli are used, characteristics and contexts of the stimuli, and practical and ethical considerations when using the stimuli.

Methods

This article is based on an expert opinion review of the sexual psychophysiology literature.

Results

First, we discuss the settings in which sexual stimuli are typically used and evaluate the ecological validity of each setting. Second, we review the types of sexual stimuli used in sexual response research, including physical characteristics, depicted sexual activity, and context, and the impacts of these characteristics on sexual response. Last, we discuss the practical and ethical considerations that come with the choice and use of sexual stimuli in clinical and research settings. We address potential limitations of certain sexual stimuli, including practical and ethical considerations such as participant vs experimenter choice, diversity and representation, and proper sourcing of sexual stimuli for use in clinical and research applications. Discussions on the future applications of sexual stimuli, such as the use of virtual reality, and ethical considerations in terms of user-generated Internet sexual stimuli are also explored.

Conclusion

We provide an expert opinion review of the literature regarding use of sexual stimuli for clinical and research applications and offer best use practices and recommendations.

Effect of a Condom Cover on Vaginal Photoplethysmographic Responses

INTRODUCTION

The vaginal photoplethysmograph (VPP) is a reusable intravaginal device often employed in sexual psychophysiology studies to assess changes in vaginal blood flow, an indicator of sexual arousal.

AIM

To test whether placing a disposable cover on the VPP probe impacts the acquired data. A condom cover would reduce risk of disease transmission and likely increase participant comfort but may negatively impact the VPP signal.

METHOD

The genital responses of 25 cisgender women (mean age = 21.3 years, standard deviation = 2.6) were assessed with VPP in a within-subjects design with 2 conditions-with and without a polyisoprene condom cover. Sexual responses were elicited by audiovisual film clips that varied in erotic intensity: nonsexual (nonsexual male-female interaction), low-intensity sexual (nude exercise), and high-intensity sexual (male-female intercourse). Women continuously rated their sexual arousal during stimulus presentations.

MAIN OUTCOME MEASURE

Change in vaginal pulse amplitude and also self-reported sexual arousal.

RESULTS

The magnitude of sexual response to each stimulus category and the overall pattern of results were found to be highly similar in the cover-off and cover-on conditions. The high-intensity sexual stimulus category elicited a greater sexual response than all other categories. The low-intensity sexual category elicited a (small) genital response in only the cover-on condition, although we suspect this is a spurious finding. There was no difference in the average number of edited movement artifacts across conditions.

CLINICAL IMPLICATIONS

Potential benefits of encasing the VPP probe with a protective cover include enhanced participant safety and comfort, especially if assessing genital responses of high-risk or immunocompromised samples. The use of a cover complies with current guidelines for reprocessing semi-critical medical devices (eg, vaginal ultrasound probes) in many regions.

STRENGTHS & LIMITATIONS

Although the idea of a VPP probe cover had been discussed among sexual psychophysiology researchers, this is the first study to empirically test whether a cover could jeopardize VPP data. Potential limitations include the use of a 10-Hz VPP sampling rate and a cover that was not tailored to the size of the VPP probe.

CONCLUSION

Placing a protective cover on the VPP probe did not appear to meaningfully impact sexual arousal or the VPP data. Based on these results and the potential advantages of a protective cover, researchers may wish to integrate the use a condom cover in their experiment protocols and clinical applications. Sawatsky ML, Lalumière ML. Effect of a Condom Cover on Vaginal Photoplethysmographic Responses. J Sex Med 2020; 17:702-715.

Effects of Individual Difference Variables, Gender, and Exclusivity of Sexual Attraction on Volunteer Bias in Sexuality Research

Sexuality research is often regarded as more intrusive than other types of research, contributing to sample self-selection biases. Researchers have consistently found that volunteers and non-volunteers for sexuality studies differ on a number of sexuality-related variables. Despite a large number of studies examining volunteer biases, relatively few have examined the effects of gender and exclusivity of sexual attraction on willingness to volunteer. Given that comparisons on the basis of gender and/or sexual attraction are frequently made in sexuality studies, understanding how these factors may contribute to volunteer bias is particularly important. In the current study, we investigated the impact of gender and sexual attraction, as well as individual difference variables, on hypothetical willingness to volunteer for a variety of sexuality studies, including new measurement technologies not previously investigated. Greater proportions of men and individuals with any degree of same-gender attraction reported that they were willing to volunteer for eye tracking and psychophysiology studies, whereas there were no significant effects of gender or sexual attraction on willingness to volunteer for sexuality surveys. The proportions of volunteers willing to participate were inversely related to study invasiveness. Greater sexual experience and more positive sexual attitudes were significant predictors of willingness to volunteer, whereas gender, sexual attraction, and other sexuality characteristics were not significant predictors. Implications of volunteer bias for research findings are discussed. Strategies to minimize volunteer bias and to examine whether or not recruited samples differ from the population are provided.