Virtual reality (VR) technology is rapidly advancing and finding applications in diverse markets, the pornography industry included. According to annual statistics of the pornography website Pornhub, terms related to VR porn regularly rank amongst the most searched categories in recent years [1–4]. The popularity of VR porn lies in its ability to capture real pornographic scenes with three-dimensional (3D) cameras with 180-degree or 360-degree views of the environment. In 180-degree VR porn, the camera captures a half-circle view of the scene, while in 360-degree VR porn, the camera captures a full-circle view. By putting on a VR headset, the user is transferred into the 3D scene. Typically, the camera is positioned in a way that makes the user feel as though they are a participant in the scene and witnessing the sexual activity from the viewpoint of a person involved. This category is denoted as "point of view" (POV) and is designed to provide a more realistic and immersive experience compared to the third-person perspective (3PP). In 3PP, the camera is typically positioned outside the scene. It provides a traditional view of seeing more of the performers and the setting, used primarily in two-dimensional (2D) modality, which may be less immersive than POV.
Despite the widespread popularity of 3D porn, only four studies employing experimental design to study its impact on sexual response were published [5–8]. Most of them explored the feeling of (sexual) presence and subjective sexual arousal. The concept of presence, as used in psychological literature, is described as the subjective impression of being in the virtual environment ("being there") [9]. Sexual presence is its extension that arises from the use of technology to mediate an experience of sexual arousal [10]. Subjective sexual arousal refers to a self-reported assessment of feeling sexually aroused and is usually aligned with the stated sexual preferences of participants [11]. Two studies [5, 8] compared the responses of male participants to presentation modality: 2D (on a desktop monitor) vs. 3D (in a VR headset). Both studies used POV videos depicting consensual heterosexual activities from a male perspective. Simon & Greitemeyer [8] reported that 3D modality induced higher physiological response (measured via skin conductance), subjective sexual arousal (both continuous and retrospective), general and sexual presence with medium to large effects (ƞ2= .12; .35; .47, .82; .78, respectively) compared to 2D modality. The authors also reported a positive correlation between the sexual presence and subjective sexual arousal in both modalities (2D and 3D). Dekker et al. [5] focused on the emotional and relational dimensions of each modality. They reported that men felt higher subjective sexual arousal, and desire for the actresses, felt more desired, flirted with, looked into the eyes, and felt a greater urge to interact with the actresses in 3D compared to 2D modality.
In addition to the presentation modality (2D vs. 3D), Elsey et al. and Milani et al. [6, 7] tackled a perspective stance (POV vs. 3PP) and added female participants to their sample. Both studies used VR headsets for all conditions, but in the 2D modality, participants did not have an opportunity to look around the scene. In line with the studies mentioned above, men reported greater subjective sexual arousal and presence in 3D modality, and those feelings heightened in POV [6]. Female participants also reported increased general and sexual presence [6, 7] in the 3D modality, but the results were ambiguous regarding subjective sexual arousal in both conditions.
Milani et al. [7] reported an increase of subjective sexual arousal in 3D over the 2D modality (although with a small effect, ƞp2=0.11), whereas Elsey et al. [6] did not. A study by Milani et al. [7] used high-quality, women-centered erotica, while Elsey et al. [6] used videos aimed more at male viewers. The selection of appropriate videos is very important in measuring women's sexual responses [12, 13]. Stimuli used by Milani et al. [7] may enable women to enjoy more the arousing aspects of the videos in 3D modality than male-centered videos [6]. Additionally, Elsey et al. [6] employed between-subject design (participants were exposed either to 2D or 3D modality), whereas Milani et al. [7] within-subject design, which may also account for discrepant results.
The second inconsistency was an increased subjective sexual arousal to POV porn reported by Elsey et al. [6] and no significant difference in perspective stance by Milani et al. [7]. Previous studies used traditional sexual stimuli, such as erotic imagery, stories, images, or sexual videos. They found that women's subjective sexual arousal amplifies with the ability to attend to their own sexual feelings besides sexual stimuli [14, 15] and to imagine themselves as a participant in a sexual stimulus [16–19]. These findings suggest that allocating attention to erotic stimuli and emotional reactions intensifies subjective sexual arousal. Study participants [6, 7] did not receive any instruction on how to attend to the stimulus, so we can only speculate whether POV mediates the feeling of being an actress or is somewhat off-putting as participants do not see the reactions of the female actress, which can hinder their excitement.
Taken together, the impact of the presentation modality of perspective stance on female sexual arousal is rather unclear. Also, none of the studies utilizing VR technology have yet measured the genital arousal of participants. Although genital arousal can be elicited reliably in heterosexual women presented with sexual stimuli in laboratory settings, such arousal does not often correspond to their subjective sexual arousal as it does in men [20, 21]. The discordance shown by heterosexual women between genital and subjective sexual arousal likely reflects the difference between automatic and controlled processes. According to an information processing model (IPM) [22] of sexual response, genital and subjective sexual arousal are mediated by two cognitive pathways. Genital response largely depends on quick, automatic processing and subjective sexual arousal on slower, controlled processing of sexual cues. The presence or absence of sexual activity appears to be the primary factor influencing genital arousal in women when exposed to sexual stimuli [23, 24] [25]. However, female genital arousal is, to some degree, sensitive to the intensity of the sexual activity depicted in stimuli, e.g., videos depicting sexual intercourse elicit greater genital arousal compared to videos depicting solo masturbation, caressing, or kissing [26]. Nevertheless, once the stimulus is of high intensity, the genital response seems to be unaffected by a perspective stance [16, 19]. For the same reason, it may be unaffected by presentation modality.
While 3D modality, and especially POV, seems to offer a more immersive sexual experience, the impact of VR porn on the female sexual experience is somewhat ambiguous. To unfold this puzzle, we compared presentation modality (3D vs. 2D) and perspective stance (POV vs. 3PP) on women's subjective sexual arousal, pleasantness ratings, feelings of sexual presence, and genital arousal while watching sexual audiovisual stimuli. We expected sexual presence and subjective sexual arousal to be higher in 3D compared to 2D modality [7] and in POV compared to 3PP [6]. Further, we expect genital arousal to be unaffected by either condition, as all the stimuli are of high intensity across all conditions [16].