Sexual Arousal in Men Exposed to Visual Stimuli With and Without Facial Blurring: Arousal in response to blurred stimuli was significantly higher than nonanonymized stimuli

A Comparison of Sexual Arousal in Men Exposed to Visual Stimuli With and Without Facial Blurring. Leah Rosetti et al. Sexual Abuse, Feb 22 2019, https://doi.org/10.1177/1079063219828784

Abstract: The role of the facial images in arousal and attraction has been examined before but never via penile plethysmography (PPG). This retrospective chart review aimed to determine the significance and magnitude of differences in arousal measured by PPG in 1,000 men exposed to slide stimuli with or without facial blurring in subjects of various ages. Arousal in response to blurred stimuli was significantly higher than nonanonymized stimuli with modest effect sizes for slides across age and gender categories. Facial blurring increased differences in arousal between adults and adolescents with a modest effect size. Our findings support the use of facial blurring to further protect the anonymity of models and limit the ethical and legal challenges of using slide stimuli with child models.

Keywords: penile plethysmography, sexual arousal, facial blurring, paraphilias

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The effect of stimulus modality on arousal has been examined in depth. Videotapes and auditory stimuli of preferred sexual scenarios have proven to be more effective than still slides at provoking sexual arousal based on self-report and measured changes in penile tumescence in men with paraphilic and nonparaphilic interests (Fedoroff et al., 2009; Pithers & Laws, 1995). Research has also indicated that different types of stimuli are more effective at measuring differences in PPG arousal between men with different paraphilias. For example, auditory stimuli have been found to be most effective at eliciting arousal in response to sexual coercion, whereas visual stimuli tend to be more effective in discerning age and gender preferences (Lalumière & Harris, 1998).

Other elements of stimuli have been shown to contribute to arousal, though these elements are not necessarily controlled for within or between sites. For example, the presence of sound in visual stimuli has been shown to increase levels of arousal in subjects (Gaithier & Plaud, 1997). In addition, quality and realism of stimuli also play a role in arousal responses; response to still slides is affected by clarity and brightness, whereas response to audio is affected by loudness and pitch (Sekuler & Blake, 1994). Also, perceived attractiveness of the actors portrayed has an impact on arousal to video (Janssen, Carpenter, & Graham, 2003) and to still images (Landolt, Lalumière, & Quinsey, 1995). One element that has not been previously controlled for in stimuli but that we propose has an effect on arousal is the presence of facial blurring.

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It may seem counterintuitive that removal of the face from a stimulus increases one’s sexual response as measured by PPG, as the face is replete with information regarding attractiveness. We theorize that facial blurring may increase sexual arousal by several mechanisms, including eliminating differences in perceived facial attrac-tiveness of models, refocusing attention to areas of the body that are implicated in sexual arousal, and allowing men to project their own preferences or fantasies onto the model.

The  importance  of  the  face  in  regulating  perceived  attractiveness  of  subjects  has  been  previously  studied  using  a  variety  of  techniques,  including  the  visual  process  method  and  eye  movement–tracking  studies.  In  the  visual  process  method,  partici-pants  uncover  one  body  part  at  a  time  to  determine  the  attractiveness  of  the  model  (Hassebrauck,  1998).  This  study  demonstrated  that  male  and  female  subjects  most  often chose the face as the first area to uncover when determining the attractiveness of a member of the opposite sex in a bathing suit. The author posited that facial attractive-ness played a much larger role than the attractiveness of the body, possibly because men look at the face for emotional information, such as level of sexual excitement. It is  possible  that  if  the  faces  of  the  models  used  in  our  stimuli  were  found  to  not  be  attractive to the subjects, that this moderated their arousal to the stimuli, whereas with-out facial features, participants had only the body features to impact arousal.

Eye-tracking studies have previously demonstrated that when viewing slides of mod-els, men focus first and longest on faces compared with other body parts (Attard-Johnson &  Bindemann,  2017;  Hall  et  al.,  2011;  Nummenmaa  et  al.,  2012).  Gaze  preference  toward  faces  was  also  shown  in  men  with  pedophilia  compared  with  healthy  controls  (Fromberger  et  al.,  2013).  When  examining  nude  adult  and  child  models,  men  with  pedophilia  fixated  longest  on  the  faces  of  children,  followed  by  the  pelvic  regions  of  children, whereas the healthy controls fixated on faces of adults for the longest period followed by the chest regions of adults. When comparing nude versus clothed models, men spend less time examining the face and more time looking at the chest and pelvic regions  in  nude  models  (Nummenmaa  et  al.,  2012).  This  study  further  demonstrated  pupillary dilation in response to viewing the chest and pelvic regions, suggesting that the participants were more aroused by these regions. Attard-Johnson and Bindemann (2017) found that when viewing clothed subjects, nude subjects, and nude subjects with both chest and genitals blurred, men viewed the faces longest for all three image types, but spent more time viewing the chest and pelvic region when the model was nude

.When the face is not available to provide emotional cues or contribute to a model’s perceived attractiveness, focus must be shifted elsewhere. Presumably, subjects would look  toward  the  chest  and  genitals  for  information  regarding  attractiveness  and  as  a  catalyst for sexual arousal. In one study that blurred the faces of their models to ensure the anonymity of their clothed (flesh colored vest and briefs) female volunteers, men tended to focus their attention on the chest and torso regions when rating attractiveness (Cornelissen, Hancock, Kiviniemi, George, & Tovée, 2009).

It is possible that facial blurring allows men to better able to focus on elements of stimuli that align with their specific sexual interests. Studies suggest that men’s fanta-sies are more likely, than those of women, to contain a focus on specific elements of a partner’s body and specific sexual acts (Arndt, Foehl, & Good, 1985; Barclay, 1973; Goldey, Avery, & van Anders, 2014; Joyal, Cossette, & Lapierre, 2015; Knafo & Jaffe, 1984; Zurbriggen & Yost, 2004).

Previously, Murphy, Ranger, Fedoroff, et al. (2015) proposed that audiotapes may be more effective for individuals who are aroused by very specific elements of a stim-ulus  set,  allowing  them  to  mentally  tailor  scenarios  to  fit  their  particular  interests,  which may not be possible with video or slide stimuli that are full of visual cues. Facial blurring may be a similar take on this concept, allowing men to refocus their attention on the most personally salient aspects of a stimulus to elicit arousal.

Furthermore,  facial  blurring  may  allow  subjects  to  depersonalize  the  model  to  a  degree that they have diminished concern for the ethical implications of their arousal. This technique serves to make models more generic, diminishing the guilt that a subject may feel for becoming aroused by a child or adolescent. In this way, models may become less likely to be viewed as individuals with emotions and rights, and more likely to be a blank canvas on which subjects can project their own sexual desires and fantasies.

We analyzed our data for differences in arousal between adult and underage model stimuli to determine whether facial blurring affected the difference between responses to  children  and  adults  by  using  differential  indices.  We  did  find  that  facial  blurring  increased differences in arousal between adults and adolescents, by increasing penile response to adults significantly more than to adolescent stimuli. It should also be noted that our effect size for this finding was modest. This finding did not hold for younger or older child categories, so the use of this technique is unlikely to improve sensitivity and specificity of stimuli.