Facial Behavior While Experiencing Sexual Excitement

See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/226186556 Facial Behavior While Experiencing Sexual Excitement Article in Journal of Nonverbal Behavior · March 2011 DOI: 10.1007/s10919-010-0097-7 CITATIONS READS 15 1,262 3 authors, including: José-Miguel Fernandez-Dols Carlos Crivelli 81 PUBLICATIONS 1,486 10 PUBLICATIONS 42 Universidad Autónoma de … CITATIONS SEE PROFILE Universidad Autónoma de… CITATIONS SEE PROFILE Some of the authors of this publication are also working on these related projects: Two projects: (a) EMNA and (b) Quixoteism View project All content following this page was uploaded by Carlos Crivelli on 20 February 2015. The user has requested enhancement of the downloaded file. J Nonverbal Behav (2011) 35:63–71 DOI 10.1007/s10919-010-0097-7 BRIEF REPORT Facial Behavior While Experiencing Sexual Excitement José-Miguel Fernández-Dols • Pilar Carrera • Carlos Crivelli Published online: 16 October 2010  Springer Science+Business Media, LLC 2010 Abstract We analyzed the facial behavior of 100 volunteers who video-recorded their own expressions while experiencing an episode of sexual excitement that concluded in an orgasm, and then posted their video clip on an Internet site. Four distinct observational periods from the video clips were analyzed and coded by FACS (Facial Action Coding System, Ekman and Friesen 1978). We found nine combinations of muscular movements produced by at least 5% of the senders. These combinations were consistent with facial expressions of sexual excitement described by Masters and Johnson (Human sexual response, 1966), and they included the four muscular movements of the core expression of pain (Prkachin, Pain, 51, 297–306, 1992). Keywords Emotion Facial expression
Sexual behavior
Enjoyment
Sexual excitement
Pain
Introduction Given its obvious link to reproductive success, sexual function and dysfunction are vital topics. Recent advances in the study of human sexual behavior and its neural basis (Arnow et al. 2002; Karama et al. 2002; Pfaus 1999) have found that sexual excitement involves not only motor and somatosensory processes but also cognitive and emotional processes (Meston et al. 2004). The cognitive and emotional components of sexual excitement lead to an interesting but relatively neglected question: is there a facial expression of sexual excitement? For obvious ethical and conventional reasons, this question has been little studied. Sexuality is a potentially controversial issue about which no one is indifferent, provoking highly emotional positive or negative reactions. Furthermore, everyday, spontaneous sexual behavior is a quintessentially private activity not open to public scrutiny. J.-M. Fernández-Dols (&)
P. Carrera
C. Crivelli Facultad de Psicologı́a, Universidad Autónoma de Madrid, 28049 Madrid, Spain e-mail: jose.dols@uam.es 123 64 J Nonverbal Behav (2011) 35:63–71 Masters and Johnson (1966) provided what is probably still the most exhaustive observational study of facial expressions of sexual excitement. They observed 10,000 ‘‘complete cycles of sexual responses’’ of 382 females and 312 males, and their findings are still considered to be an accurate source of information (see, for example, Meston et al. 2004). They observed a phase of intense sexual excitement prior to orgasm (‘‘plateau phase’’) during which was seen ‘‘frowns, scowls or grimaces,’’ ‘‘contraction of the musculature surrounding the mouth,’’ and, later in this phase, opening of the mouth (Masters and Johnson, pp. 295–296). Mouth opening was more frequent in coitus, whereas clenched jaws and flared nostrils were more frequent in self-manipulation. A striking feature of Masters and Johnson’s record is that their terms of choice (‘‘grimace,’’ ‘‘scowl,’’ and ‘‘frown’’) suggest that facial expressions during sexual excitement are similar to facial expressions usually categorized as expressing pain. Indeed, Hughes and Nicholson (2008) pointed out this similarity and studied recognition of expressions of sexual pleasure and of expressions of pain. Participants were significantly more skilled at recognizing facial expressions of pain than facial expressions of pleasure, but rates of recognition of sexual pleasure were still very substantial (79.8% for pain and 75.3% for pleasure). Unfortunately, neither Masters and Johnson nor Hughes and Nicholson performed a detailed analysis of the facial expressions they studied with any of the modern objective coding systems. This aspect of their research leaves us with questions about their description of the muscular movements involved. An Internet site (http://www.beautifulagony.com), as retrieved on February 21st 2008, displays 1048 short (approx. 30–360 s) video clips of volunteers who recorded their own facial behavior while performing (presumably self-manipulative) sexual behaviour and then reaching an orgasm. The website provides detailed instructions to those who want to post their clips, including instructions about the position of the camera and lights and, most important, an explicit request to avoid exaggeration or simulation: Frame the shot like you see on the site - full face, no nudity, preferably from a point of view above the nose (…). Make sure you have good light. Daylight from a nearby window is best. If you’re using a lamp, it should be to one side, close to you but not too close to the camera, so the light is graded across your face. It will need to be a bright lamp and set the white balance manually to ‘‘indoor’’ (all camcorders have this control). Please don’t have any music or the TV playing (…) we’re only interested in reality, not performances, impressions, or exaggeration (…) Every Agony contributor is paid a fee before their video goes up, providing their contribution is accepted. To be accepted you just have to make sure the Release Form is correctly filled out, include a legible copy of government-issued photo ID that shows you’re over 18, and ensure that your video meets the technical standards. (retrieved at http://www.beautifulagony.com/public/main.php?page=submit on February 14th 2008). Clips posted at the website are edited versions of the original tapes submitted by the volunteers. The clips include the senders’ orgasm as well as a substantial portion of the excitement-plateau phases (i.e., the period prior to orgasm) and occasionally short records of the resolution phase (i.e., relaxation period after the orgasm). These clips are a valuable source of information about facial expression during the sexual cycle. They provide an opportunity (1) to test the accuracy of Masters and Johnson’s description and (2) to obtain a more precise description of the observed facial expressions through the use of a standard objective coding system. 123 J Nonverbal Behav (2011) 35:63–71 65 Sample We selected 100 clips posted on the site by 100 different senders (74 females and 26 males). To reach this 100-sender sample, we had to consider the first 119 clips posted on the site. The 19 excluded clips lacked adequate lighting or a full view of the sender’s face, or were not available at the time the clips were downloaded from the site. Procedure The Facial Action Coding System (FACS, Hjortsjö 1969; Ekman and Friesen 1978) codes muscular movements based on visible changes in the facial surface. One FACS-trained coder analyzed all senders’ muscular facial actions (excluding head movements because most senders’ heads were lying on a horizontal surface). A second FACS-trained coder analyzed a random sample of 50 clips. Inter-rater agreement according Cohen0 s kappa was .80. Coding was divided into four periods according to Masters and Johnson’s division of the sexual cycle: (1) (2) (3) (4) Baseline-Excitement: the 6 s at the beginning of the clip in which the sender is beginning to be sexually excited. Plateau: the first half of the 12-second sequence immediately before the Resolution period. This period is marked by changes in sounds and breathing that marked an imminent orgasm. Plateau-Orgasm: the second half of 12-second Plateau sequence. This second sixsecond period includes signs of orgasm and finishes when the orgasm likely ended as indicated by the senders’ faces becoming obviously relaxed and their switching into the fourth period. The ascription of orgasm to this Plateau-Orgasm period is based on the apparent muscular tension and sounds produced by the sender, an estimate that fits Masters and Johnson’s (1966) estimate of the duration of a ‘‘normal’’ female orgasm (4 to 6.4 s long; for other estimates see. Meston et al. 2004), whereas a masculine orgasm is usually shorter (Holstege et al. 2003). Resolution: the period from the time the sender relaxes, keeps the eyes open and moves the head to gaze around, focusing on other activities than sex (e.g., adjusting the camera or interacting with someone). The duration of this period varied from one clip to the next and rarely reached 6 s (M = 3.64 s). Results The two most relevant periods are the two halves of the 12-second sequence of intense sexual excitement and orgasm immediately before the final short Resolution period. We divided this 12-second sequence into two halves in order to distinguish between the facial behavior in the plateau and any potential reflex-like movements during the orgasm. Single Action Units Table 1 lists all muscular movements (action units, AUs, in the FACS terminology) that occurred in at least five senders in any period. Table 1 shows the number of senders who produced each AU at least once during a period. AUs with the highest frequencies across 123 66 J Nonverbal Behav (2011) 35:63–71 Table 1 Frequencies of AUs across conditions AUs (isolated or in combinations) Baseline-excitement Plateau Plateau-orgasm Resolution AU42 (slit eyes) 00 a 05 ab 07 b 04 ab AU43 (closed eyes) 73 a 86 b 92 b 04 c AU4 (frown/brow lower) 17 a 64 b 48 c 00 d AU6 (cheek raise) 00 a 20 b 06 c 05 ac AU10 (upper lip raise) 00 a 07 b 02 ab 00 a AU12 (lip corner pull) 09 a 10 a 17 a 36 b AU25 (lips part) 45 a 45 a 44 a 35 a AU26 (jaw drop) 22 a 79 b 67 c 04 d AU27 (mouth stretch) 00 a 05 a 03 a 00 a AU 29 or 30 (jaw thrust, or jaw sideways) 00 a 16 b 15 b 00 a N = 100. Because of the sample size, the frequency shown also corresponds to the percentage of individuals showing the AU. Frequencies with different subscripts in the same row differ significantly at p \ .05 according to a McNemar test for two related samples the first three periods were 43 (closed eyes), 4 (frown/brow lower), and 26 (jaw drop). In the Baseline-Excitement period we found closed eyes (AU43), lips part (AU25), frown/ brow lower (AU4), jaw drop (AU26), and lip corner pull (AU12). Compared to the Baseline-Excitement period, closed eyes (AU43), frown/brow lower (AU4), and jaw drop (AU26) increased in the Plateau period, during which there were also, as in Baseline-Excitement, occurrences of AU25 (lips part) and AU12 (lip corner pull). Furthermore, in the Plateau period there were also occurrences of AU42 (slit eyes), AU6 (cheek raise), AU10 (upper lip raise), AU27 (mouth stretch), and AU29 and AU30 (jaw thrust and jaw sideways). Compared to the Plateau period, the Plateau-Orgasm period showed a significant decrease in frowns, cheek raise, and jaw drop. Finally, the Resolution period is the time in which most of the facial behaviors characteristic of previous periods faded: senders opened their eyes, frowns disappeared and the basic ingredient of a smile (AU12, lip corner pull) increased significantly in frequency. We found significant sex difference in the frequency of two relevant action units in two specific periods: AU43 (closed eyes) was more frequent in females than males during the Plateau period (v2 (1) = 4.87, p = .027), whereas AU10 (upper lip raise) was more frequent in males than females during the Plateau-Orgasm period (v2 (1) = 5.8, p = .016). Combinations of Action Units Some AUs occurred in combination with others. Table 2 shows all AU combinations produced by at least 5% of the senders in any period. Senders produced 51 instances of AU combinations, but only 10 different combinations. Table 2 also shows the frequency of neutral faces (i.e., lack of any codable AU throughout a period). The Baseline-Excitement period included some neutral faces and some combinations of closed eyes with lips parted (AU25 ? AU43) or jaw drop (AU26 ? AU43). During Plateau and Plateau-Orgasm neutral faces disappeared, but one of the same two combinations (closed eyes and jaw drop) occurred with higher frequency. The Plateau and PlateauOrgasm phases also included other combinations, principally AU4 (frown/brow lower) or AU4 ? AU6 (frown/brow lower and cheek-raise) with closed eyes and lips parted or closed eyes and jaw drop. There were also low but relevant frequencies of combinations in 123 J Nonverbal Behav (2011) 35:63–71 67 Table 2 Frequencies of AU combinations across conditions AU combination BaselinePlateau Plateau- Resolution excitement orgasm Neutral 11 a 00 b 00 b 20 a 25 ? 43 lips part and closed eyes 31 a 18 a 21 a 00 b 26 ? 43 jaw drop and closed eyes 14 a 30 b 36 b 00 c 4 ? 25 ? 43 frown/brow lower, lips part, and closed eyes 00 a 16 b 15 b 00 a 4 ? 26 ? 43 frown/brow lower, jaw drop and closed eyes 00 a 33 b 21 c 00 a 4 ? 6 ? 25 ? 43 frown/brow lower, cheek raise, lips part, and closed eyes 00 a 07 b 05a b 00 a a 07 b 02 a b 00 a 4 ? 6 ? 26 ? 43 frown/brow lower, cheek raise, jaw drop, 00 and closed eyes 4 ? 7 ? 26 frown/brow lower, tight eyelids, and jaw drop 00 a 07 b 02 a b 00 a 7 ? 25 tight eyelids and lips part 00 a 01 a 05 a 00 a 6 ? 12 Duchenne smile 00 a 00 a 00 a 05 a N = 100. Because of the sample size, the frequency shown also corresponds to the percentage of individuals showing the AU. Frequencies with different subscripts in the same row differ significantly at p \ .05 according to a McNemar test for two related samples which frown/brow lower and jaw drop (AU4 ? AU26) or lips part (AU25) were combined with tight eyelids (AU7) rather than fully closed eyes. Finally, in the Resolution period we found a significant increase of neutral faces. Duchenne smiles (smiles in which the orbicularis oculi raises the cheeks, causing wrinkles in the eye region; see Ekman et al. 1990) reached a frequency of nearly 5%; this increase in frequency was close to statistically significant according to the McNemar Test (p = .06). Only one of the combinations described in Table 2 showed a sex difference. In the Baseline-Excitement period, AUs 26 ? 43—closed eyes and jaw drop—was more frequent in female than in male senders (v2 (1) = 5.72, p = .017); this difference seems to indicate that this combination—highly frequent in the following two periods—was present in the female senders during the Baseline period. Some Caveats and Limitations Our work is afflicted by the problems of any field study. First, the individuals in our sample were self-selected, and we cannot exclude a potential bias due, for example, to the prevalence of some personality traits in our senders (extroversion?). Nevertheless, the personality of individuals has not been found to affect the specific pattern of other facial expressions, although it has been found to affect the frequency of some expressions and the degree of expressivity (Keltner and Ekman 2000). Second, our sample had more females than males. This imbalance may have jeopardized our findings on gender differences, questioning the validity of what minimal differences we found. On the other hand, Masters and Johnson (1966, p. 294) explicitly reported the absence of gender differences in the patterns of facial expressions during sexual excitement. Third, although all the records we analyzed gave the appearance of individuals achieving sexual excitement through selfmanipulation, we do not know the way in which the senders were actually stimulated nor what went on behind the camera. 123 68 J Nonverbal Behav (2011) 35:63–71 It could also be argued that expressions could have been faked or influenced by extrinsic factors such as the name of the website (‘‘agony’’ might induce pain expressions). We cannot exclude a systematic collective bias in the senders, but we believe that such a bias is implausible for three reasons. First, Masters and Johnson (1966) also found negative painlike expressions (‘‘frowns, scowls, and grimaces’’) in a context with no implicit demand to show agony. Second, because the senders voluntarily underwent the sexual experience, recorded themselves, and then exhibited their recordings, a more plausible bias would be that senders wanted a pleasant experience and wanted to exhibit themselves as having a pleasant experience.1 And third, the large and diverse sample argues against the idea that some muscle movements were posed or exaggerated. Indeed, although no systematic data were available on the website, the website is international and the senders appeared to be from various ethnic groups. Thus, the sample was more likely to have included idiosyncratic movements than a collective bias toward specific movements. Conclusions and Further Questions We began with the question whether there is a facial expression of sexual excitement. Our results showed that there is much facial activity during the Plateau and Plateau-Orgasm periods of sexual excitement. Unlike the periods before and after these periods, no one showed a neutral face. Their facial activity was not random, but the majority of people showed certain AUs, although no combination is seen in a majority of senders. The limitations of our study notwithstanding, our findings raise a series of interesting questions. Is the Expression of Sexual Excitement Similar to the Expression of Pain? Our findings confirm Masters and Johnson’s (1966) and Hughes and Nicholson’s (2008) observations about the similarity between the expression of pain and the expression of sexual excitement. The individual and combined facial movements observed here are strikingly similar to those described as the expression of pain. Prkachin (1992) described the prototypical expression of pain as including four core facial movements: brow lower/ frown, (AU4), orbit tightening (which includes cheek raise, AU6, or tight eyelids, AU7), upper lip raise (AU10), and eye closure (AU43). In other studies (e.g., Craig et al. 1991), researchers have described other recurring facial movements (e.g., lip corner pull, lips part, jaw drop) in pain. All these action units were found here in the sexual excitement phases. 1 In our study we do not have an explicit subjective report of the senders’ emotion. Nevertheless, indirect clues provide convergent validity for our belief that the senders were displaying more than just a physical, reflex-like response. The web-site’s explicit instructions for the senders (which emphasize the hedonic side of the experience), the senders’ vocal behavior during the clip, and, in most cases, the senders own comments in a different clip also posted at the website, all convey the impression of an explicit link between sex and enjoyment in the sender’s mind. Furthermore, in the current version of the website (as retrieved in March 2010) senders are requested to upload not only the record of their sexual experience but also an additional video in which they are invited to answer a series of questions. One question concerns their subjective experience during the recording of their orgasm (‘‘how was your beautiful agony experience?’’). We selected the last 25 senders posted on the website (as retrieved on March 5th 2010) who explicitly reported a positive experience in answer to this question. Then we analyzed a three-second video sequence taken at random from the plateau-orgasm period of each of the 25 senders. The distribution of facial movements did not differ from the distributions reported in Table 1. These additional data show that the subjective experience that accompanied the facial behavior of Tables 1 and 2 was pleasant rather than painful. 123 J Nonverbal Behav (2011) 35:63–71 69 In both pain and sexual excitement, not everyone shows the identical facial pattern, but everyone shows a limited range of movements. Although our results confirmed Masters and Johnson’s (1966) and Hughes and Nicholson’s (2008) observation of the striking similarity between pain and sexual excitement expressions, the two are probably not identical. Hughes and Nicholson found that although the expression of one is sometimes mistaken for the other, observers can distinguish the two with better than chance accuracy. This finding suggests subtle differences between the two, perhaps in the dynamics of the movements that might be missed in the FACS coding. Hughes and Nicholson also found sex of both sender and observer influenced the judgments of whether an expression was pain or sex. This finding suggests that context may influence the expression or the judgment of that expression. Is there a Psychological Meaning of the Expression of Sexual Excitement? Sexual excitement and orgasm are both linked to the ‘‘reward areas’’ of the basal ganglia (Arnow et al. 2002; Holstege et al. 2003; Karama et al. 2002; Rauch et al. 1999; Redouté et al. 2000), as is also the case with the perception of other positive pleasant non-sexual stimuli, such as food, pictures, friendly expressions, happy memories or gentle touch. Is this sexual reward embedded in a prototypical emotional episode? Researchers (Arnow et al. 2002; Meston et al. 2004) have found that some of the cortical and subcortical areas activated during sexual excitement are related not only to the presentation of rewards but also to the perception of emotional stimuli, autonomic and emotional processing, and goal-directed behavior. Current research in neuroscience (see Bianchi-Demicheli and Ortigue 2007; Karama et al. 2002; Redouté et al. 2000; Stoleru et al. 1999;) describes human sexual excitement as a multidimensional experience that involves the appraisal of a stimulus as a sexual incentive, a specific affective quality of the experience, and a goal-directed behavior. Research on the experiential processes during sexual excitement shows that voluntary engagement in sexual activities requires an appraisal or assessment of the affective meaning of these activities (Pinkerton et al. 2003, see also Frijda 2007). Participants in experimental settings very similar to the situation of our participants (e.g., laboratory studies on the physiological and neural correlates of orgasm) reported that mental imagery was a necessary requisite for reaching the plateau-orgasm phase and that the experience was pleasurable (see Holstege et al. 2003). Thus, sexual excitement is not merely a genital sensation, even in a laboratory setting. These data suggest that our participants probably reached intense sexual excitement by means of a complex cognitive-emotional process. The most suitable everyday-language category for describing this multidimensional experience might be ‘‘enjoyment’’ or ‘‘ecstasy’’ (see Frijda 1997). Episodes of sexual excitement are recognized as intense enjoyment by both men and women (Garcia et al. 2008), and sexual and non-sexual episodes of positive valence and high-emotional-arousal share the same patterns of neural activation (Rauch et al. 1999). Should we conceptualize the facial expression of sexual excitement as an expression of enjoyment? A first negative argument against the ‘‘expression of sexual enjoyment’’ hypothesis might be based on the argument that the analyzed sequences conclude in an orgasm, and orgasm is not emotion but a ballistic response similar to a reflex-like reaction. Denying the cognitive and emotional complexity of orgasm is debatable: Mah and Binik’s (2001) three-dimensional model of orgasm includes a sensory, an evaluative (How does the orgasm feel?), and an affective dimension (How does the person feel during the orgasm?). The evaluative dimension is a complex appraisal which, for example, includes a 123 70 J Nonverbal Behav (2011) 35:63–71 pleasure check. The affective dimension includes different forms of emotion, such as joy. Appraisal of sexual incentives through imagery seems a key factor not only during the excitement-plateau phases but also during orgasm itself. Holstege et al. (2003) found that the visual cortex (BA 18) showed increases in regional cerebral blood flow during orgasm, despite the fact that the volunteers had their eyes closed. But even if orgasm is considered as a non-emotional, ballistic reaction, the characteristic facial expressions that we have described were already produced in the excitement and plateau phases that preceded and concluded in orgasm. Our participants were, at some particular point of the sequence, experiencing orgasm, but their expressions were built up during the excitement and plateau phase (actually, only one configuration is significantly different in the Plateau-Orgasm period, see Table 2, and the difference affects just one muscular movement, jaw drop, see Table 1). A second argument against the ‘‘expression of sexual enjoyment’’ hypothesis is that the facial behaviors observed in these episodes are merely symptoms of muscular tension and its consequent release, with no communicative relevance. Denying the communicative relevance of the facial behavior during sexual excitement is, in our view, debatable. From an evolutionary point of view, the unique character of universal face-to-face human coitus suggests that facial expressions of sexual excitement likely have communicative value in humans (Baumeister and Bratslavsky 1999; EiblEibesfeldt, 1989). Many facial movements appear to have emotional meaning (Darwin 1872/1965), and there is no evolutionary advantage in sending unrecognized signals. In all, it seems likely that the facial expression of sexual excitement has psychological meaning, that is, the signal is interpreted by an observer as meaningful. Additionally, if the facial expression linked to sexual excitement—an activity of such extraordinary importance for the survival of the species—is just muscular tension with no communicative content, is there any reason to assume a specific emotional meaning to any grimace, scowl, or frown displayed in other highly arousing situations?2 In this vein, facial behavior linked to pain might be mere non-expressive accidents caused by spastic muscular movement. And, in the same line of reasoning, frowns, scowls or grimaces traditionally linked to anger or disgust might also be non-specific signs of muscular tension devoid of communicative intent. Are frowns, scowls, and grimaces—either in pleasure or displeasure—mere expressions of muscular tension, blank displays that take psychological meaning from the perceiver’s rather than the sender’s mind? Acknowledgments This research was carried out within the project PSI2008-04849 funded by the Spanish Government (MICINN). 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