The clitoral activation paradox — Claimed outcomes from different methods of its stimulation

INTRODUCTION

It has been exaggeratedly claimed that sexual arousal to orgasm by penile vaginal intercourse (PVI) alone without any other sexual stimulation, especially clitoral, has a ‘myriad demonstrated benefits’ to women in terms of their psychological, physiological, and physical health compared to that induced by clitoral stimulation per se (Brody, 2010; Brody, Costa, and Hess 2012)—but see Table 1 for the actual benefits listed against the known harmful conditions that can arise even from consensual PVI. Even promoting clitoral stimulation is said to create the possibility of ‘iatrogenic damage’ (Brody and Costa, 2008) but such evidence that this has occurred has never been presented. Furthermore, it is also stated that if PVI is accompanied by clitoral stimulation it detracts from impairs or diminishes the purported beneficial features of PVI (Brody and Costa, 2008; Brody, 2010; Costa, 2012). It seems remarkable that Brody et al. consider PVI as the only sexual behavior that can bring about pregnancy and gene reproduction and thus is ‘rewarded’ by evolution as its so-called benefits can so easily be detracted, impaired, diminished by the added arousal from clitoral stimulation and the ‘untoward effect of other sexual activities’ (Brody, 2010). Their pathologizing and disputatious conclusions stem from studies of cross-sectional answers and correlational analysis (multiple regression) to mainly devised, nonvalidated self-report questionnaires where there is an inability to ascertain the accuracy of the women's responses despite the occasional use of a questionnaire to assess the possibility of socially desirable responses (Ballard, 1992). A number of critical features that are pertinent to their studies need to be examined. A recent and worrying development is in the field of statistics, especially in the use of p values to assess the significance of differences between clitoral associations and those of PVI. According to Ioannidis (2018) their general use to indicate that a particular finding is true, valid and worth acting on for claims where p is just below 0.05 by itself does not provide a good measure of evidence and ‘are probably false e.g., the claimed association or treatment effects do not exist’. Colquhoun (2014) had previously reported that ‘if you use p = 0.05 to suggest that you have made a discovery you will be wrong at least 30% of the time. If the experiments are underpowered, as is often the case, you will be wrong most of the time'. These warnings make a need for careful re-examination of any such statistical made claims.

In the context of women reporting their orgasmic behavior, the pretense of having one is said to be common among women with 43–58% reporting it at least once while with women in long term relationships the figure rises to 18% of their sexual activity. The most common sexual behavior is vaginal intercourse when 82% of women choose to pretend (Jern, Hakala, Kärnä, and Gunst, 2018 for full references).

No systematic investigations of possible underlying physiological mechanisms have been undertaken apart from one brain imaging study claimed for support. The conclusion from the study was that as the clitoris, cervix and anterior wall of the vagina appeared to have different sensory, but somewhat overlapping, cortical projections with a clustered location on the medial parietal lobule (Komisaruk et al., 2011) this could explain their different mental and other effects when stimulated. Unfortunately, the study has more than a number of methodological shortcomings. Like so many brain imaging studies of sexual arousal, the findings are not in agreement with previous ones that located the clitoral brain representation on the dorsolateral region of the parietal lobe (Georgiadis, Kortekaas, and Kulpers et al., 2006; Michels, Mehnert, and Boy et al., 2010). Furthermore, the study not only used ecologically invalid stimulation of the cervix and vagina using inanimate rods while the masturbation of the external clitoris was accomplished by hand tapping (both methods of stimulation previously decried by Costa and Brody, 2011 when used in other studies), but most importantly also undertook these stimulations in separate, randomized-sequenced recording sessions. The pattern of brain scan results obtained and their interpretation cannot be compared to those obtained during natural coitus where the various genital structures are stimulated functionally all at the same time and multiple, connected brain regions are activated. This picture of brain activation was revealed in another imaging study of sexual arousal by Komisaruk and Whipple (2011), their ‘Tapestry’ representation of fMRI activity in 80 Brodman and other brain regions shows a widespread activity in the brain during arousal to orgasm while similar results were also obtained in a carefully controlled more recent study (Wise, Frangos, and Komisaruk, 2017), both results conflict with the previous punctate observations. Komisaruk (2010) has admitted that ‘all major brain systems evidently contribute to women's orgasms’. The review of the future of brain imaging of the sexual response by Ruesink and Georgiadis (2017) confirms this stating that ‘human sexuality does not rely on a single sex nucleus. Rather, it involves many—sometimes quite generic-brain functions including those for arousal, reward, memory, cognition, self-referential thinking and social behavior’. The punctate area projections for the clitoris, cervix and anterior wall of the vagina are thus likely to be simply an artefact of the methodology chosen that used their individual, separate stimulation.

Despite the fact that highly relevant criticisms of the studies of Brody et al. have now been published (Hurlbert and Whittaker, 1991; Laan and Rellini, 2011; Prause, 2011, 2012; Suchinsky and Lalumière, 2013; Levin, 2002, 2011a,b, 2012, 2014; Miko, Urban, Kajanová, Polák and Varga, 2014; Prause et al., 2016; Therrien and Brotto, 2016; Tavares, Laan, and Nobre, 2017), few authors who quote Brody et al. papers (Puts, Dawood and Welling, 2012; Aneja et al., 2015; Mazloomdoost and Pauls, 2015; Fleischman, 2016; Kontula and Miettinen, 2016; Maunder, Schoemaker, and Pruessner, 2017) also append in context these papers that highlight critically, not only their errors of omission and commission but also contradictory findings (see also Levin 2011b, 2014 for further comments). This creates the illusion that their interpretations and conclusions appear to be unopposed and the possible ‘canonization of false facts’ (Banobi, Branch, and Hilborn, 2011; Nissen et al., 2016). Other criticisms have been published viz: - Charland et al. (2012) and in older, non-peer reviewed web-sites (Boynton, 2006, 2009; Silverberg, 2006, 2011).

The present article explores a number of the ignored difficulties and inconsistencies with the claims that Brody et al. have made in relation to clitoral function and its effects on stimulation compared to PVI.

CLITORAL ANATOMY AND EROTIC FUNCTION

The clitoris is a sexual organ placed superior to the vaginal entrance (introitus), when stimulated it creates sexual arousal but its significant distance from the introitus makes for difficulty of stimulation during coital thrusting (Wallen and Lloyd, 2011). The explanation for this distance has been the subject of a limited number of suggestions (Kennedy and Pavličev, 2018) but none proposed can realistically be confirmed. It is a complex structure composed of internal (crura, root and vestibular bulbs) and external or visible components (body or shaft, glans, prepuce) despite idiosyncratic protestations (Puppo, 2011) about such designations (see Levin 2015 for further discussion). Its anatomical history has been described by Di Marino and Lepidi (2004). According to Mazloomdoost and Pauls (2015) the clitoris is secured to the labia and the fascia of the mons pubis by suspensory ligaments and the body and glans are attached by ligamentous tissue into the labia majora while Ingelman-Sundberg (1997) described an anatomical connection via ligaments between the anterior vaginal wall and the base of the clitoris. Because of the latter, any stretching of the anterior vaginal wall by penile thrusting will also stimulate the base of the clitoris. Thus, any penile thrusting into the vagina is bound to activate clitoral stimulation. The echographic pilot study by Buisson and Jannini (2013), admittedly unfortunately only in three females, visualized the movements of the female genitalia separately during external clitoral stimulation and vaginal stimulation by a wet tampon. Even with this weak stimulator they reported that different parts of the clitoris were involved with the two types of stimulation which could give rise to the perceived perception by women of two types of arousal to orgasm (viz clitoral and vaginal) but both were actually clitoral. In a later dynamic sonographic study Foldes and Buisson (2009) imaged the genitals of five women who were able to have PVI orgasms and had highly sensitive anterior walls around the so-called G-spot area. During perineal contractions their clitoral root moved against the vaginal anterior wall. They suggested that this movement that would occur during PVI could explain the increased erotic sensitivity (i.e., the ‘G spot’) of the anterior vaginal wall.

Stimulation of the glans and shaft not only creates clitoral tumescence (but not rigidity like the penis- Toesca, Stolf, and Cocchia, 1996) and gives rise to highly pleasurable erotic feelings due to the activation of their sensory end organs (Merkel tactile discs, Pacinian corpuscles, Krause-Finger corpuscles, and free nerve endings) and the afferent supply from them to the brain via the bilateral terminations of the pudendal nerve (Pauls, 2015). What is uncertain, however, is the possible function(s) of the bulbs, are they involved in generating such erotic impulses or have they other purpose(s)? While there are no specific empirical findings that confirm their function, some authors have speculated about possible functions. Sevely (1987) suggested that ‘when they are in their puffed more exposed state they themselves are highly sensitive to gentle tactile stimulation and during coitus to pressure from the penis’. O'Connell et al. (1998), however, thought that they simply gave lateral support to the vaginal wall. Buisson et al. (2010) undertook ultrasound studies in a couple during coital activity and concluded from the images obtained that the clitoral root was pushed down upon the penile shaft by the contraction of the perineal muscles and became stimulated by it. They proposed that this was the ‘functional G spot.’ Wallen and Lloyd (2011) speculated that ‘the clitoral bulbs and bodies as well as the shaft and glans’ may well be erotically responsive. Puppo (2011), however, opined that the ‘roots of the clitoris …. do not have sensory receptors or erogenous sensitivity during vaginal intercourse’ although he could offer no empirical evidence or validation for this statement. No specific empirical test has yet been devised to establish, without question, the erotic function of all the clitoral structures.

In a self-assessment study by 749 Belgium women (aged 18–69) sexual pleasure and orgasm were found to be the strongest and the effort to attain the orgasm was the lowest when the clitoris and its sides were stimulated while the vaginal sensitivity for orgasm was lower (Bronselaer et al., 2013). In another study, Oakley et al. (2014) reported that women with anorgasmia (n = 10) possessed smaller clitoral glans and clitoral components that were further from the vaginal lumen than women (n = 20) with normal orgasmic function; their data supports some of the conclusions of Wallen and Lloyd (2011).

THE OVERLOOKED PROXIMATE FUNCTION OF THE CLITORIS IN FACILITATING REPRODUCTIVE FITNESS DURING THE FERTILE YEARS

The normal focus on clitoral function is always related simply to its erotic activity in creating sexual arousal and pleasure as described above but there is also an overlooked reproductive function during the fertile years in relation to its activity. The clue to this is in the organ's remarkable ability in creating sexual arousal far more effectively and quickly than vaginal stimulation as detailed in the previous sections. How does this function relate to facilitating reproduction? The answer is in the manner by which the female genital tract needs to adapt to process the handling of semen in the vagina and the subsequent transport of spermatozoa into the uterus/fallopian tube. The spermatozoa are ejaculated in seminal fluid that gels trapping and immobilizing them. The gel has then to be enzymatically liquefied to enable them to become motile, make contact with the various components of the ejaculate and for the first stages of capacitation (pre-capacitation) to occur before they are transported to the open, ipsilateral fallopian tube servicing the ovulating ovary. Effective clitoral stimulation during foreplay induces high sexual arousal, and activates the processes of vaginal tenting and ballooning (Masters and Johnson, 1966) where the utero-cervical complex is withdrawn by muscle contraction up into the false pelvis removing it from the semen pool and thus, crucially, preventing any premature transport of noncapacitated sperm unable to fertilize ova that would decrease reproductive functionality (see Levin 2011c, 2015 for details and references). Clitoral stimulation induces such sexual arousal very rapidly ensuring that the tenting occurs automatically to create the best genital tract conditions for possible, subsequent fertilization. This scenario explains why clitoral stimulation is initially a most important but overlooked part of the generative process and should not be regarded as alien to normal reproduction. Moreover, it would be beyond ridiculous to believe that ‘evolution’ has chosen to ‘punish’ the use of the stimulation of the clitoris by ‘noxious outcomes’ as postulated by Brody et al. as this would make no sense in terms of its now obvious identification as the initiator of changing reproductive tract conditions to facilitate possible successful reproduction. In the terms favored by evolutionists, this action of the clitoris can be interpreted as a fundamental proximate mechanism (the how) for facilitating female reproductive fitness, the designated ultimate function (the why). An important feature of this function of the clitoris is that it occurs no matter how the stimulation is brought about 2012viz by PVI, digitally, lingually or by vibrator. As far as I am aware, this now obvious ‘reproductive aspect’ of clitoral function had not received, previously, any recognition in the literature (see for example the hypothesis of clitoral function proposed by Kennedy and Pavličev, 2018). It should be noted that stimulating the clitoris also activates the processes for creating the lubrication of the vagina to facilitate penile entry and coital thrusting (Levin, 2003: Levin and Wylie, 2008) which, while clearly important to aid painless coitus, is not essential for reproduction as is the activation and induction of vaginal tenting.

CLITORAL SELF-STIMULATION DURING ADOLESCENCE

Dickenson (1949) described female masturbation (autosexuality) from his studies of over 1000 women as ‘so general an experience or conduct as to be justly considered a normal provision of nature, as a stage preparatory for heterosexual response’. According to Fortenberry (2013) masturbation is the second most prevalent adolescent sexual behavior even with its religious condemnation and substantial social stigma. However, despite its claimed prevalence there is no data that describes the age or the context of the onset of masturbation, but in a study of Spanish girls (n = 226) none under 13 reported masturbation and for 13–14 years olds it was 19% (Arnal and Llario, 2006). Robbins et al.(2011) found self-masturbation as a commonplace experience of female adolescent sexual development and an enduring normal component. Using a US population-based valid cross-sectional survey, the frequency for females masturbating for a few times in the past year was 45.5% while 22.5% reported a frequency of at least twice a week. Frequency of masturbation increased with age, 58% at 17 years of age compared to 43.3% at 14 years old. The authors reported that professional organizations such as the American Academy of Pediatrics and the American Academy of Obstetrics and Gynecology recognize masturbation as a normal component of child and adolescent development. The average retrospective age for first orgasm by masturbation is 17 years of age for women (Reynolds and Herbenick, 2003).

The Brody claim is that clitoral stimulation creates ‘noxious outcomes’ in a female's psychological, physiological, and physical health (Brody, 2010) but what he and his small coterie of co-authors have never discussed, or apparently even investigated, is a ‘dose-response’ relationship for the use of clitoral stimulation in order to obtain a ‘risk-benefit’ analysis. The only fact available about the possible duration of the effects of clitoral stimulation on the claimed advantages of PVI (Brody, 2006) is that ‘having had any use of extrinsic clitoral stimulation in the past month was associated with more use of immature defenses’ (but see Table 1). Yet surely, this aspect of clitoral effects must be a crucial aspect of their claims. Levin (2014) posed the question' for how long (hours, days, weeks?) does the use of clitoral stimulation need to occur to create the claimed dysfunctions/disorders and if it is prolonged does it create permanence? Does a single episode of clitoral stimulation affect the claimed beneficial effects of PVI? But, despite the many publications describing the ‘noxious outcomes’ of clitoral stimulation, it has never been answered.

CLITORAL SELF-STIMULATION DURING ADULTHOOD

While Brody and Costa (2008) stated that ‘clitoral orgasm is at best an intermediate state between global anorgasmia and being fully vaginally orgasmic’, many published studies discount the claim. Two set of investigators investigating masturbation commented on its role in adults. Kontula and Haavio-Mannila (2003) examined national sex surveys in Finland, Sweden, Estonia and Russia found that ‘masturbation was not a compensation for a missing sex partner but was an independent to gain sexual pleasure’ while Bancroft and Graham (2011) found that while men can use masturbation as a substitute for a sexual partner women use it as an extension of their sexual repertoire. Hurlbert and Whittaker (1991) investigated the role of female masturbation in marital and sexual satisfaction in two groups of women (n = 41), those who experienced masturbatory orgasms and those who never had experienced through self-stimulation. Significant differences between the two groups were found that showed that masturbators had significantly more orgasms, greater sexual desire, higher self-esteem, greater marital and sexual satisfaction, and required less time to become sexually aroused.

Eschler (2004) reported that only 33% of women (n = 202 Western women of reproductive age) indicated that vaginal stimulation led to orgasm compared to 77.4% who indicated that manual stimulation of the clitoris did. Studying a national representative sample of Swedish women aged 18–74- years- old (n = 1335) Fugl-Meyer et al. (2006) found that only 47% reported a lifetime ability to reach orgasm through coitus alone. A highly relevant finding from a study by Burri et al. (2010) is that even ‘women with a reported G-spot still preferred clitoral rather than vaginal orgasm (41.8% vs. 26.8%, p < 0.001)'. Gerressu, Merce, Graham, Wellings, and Johnson (2008) used both face-to-face and computer assisted self-interviewing of a stratified probability sample of the British general population. Some 36.8% of the women reported masturbating in the 4 weeks previous to the interview. It was increased with those who had a higher level of education and interestingly with those women who had reported more frequent PVI. Carvalheira and Leal (2013) found that amongst 3,687 women who completed a web-based survey 91% indicated that they had masturbated at some point in their life while 29.3% reported the activity within the past month. It appeared to be related to a greater sexual repertoire, more sexual fantasies, and greater ease in reaching sexual arousal and orgasm. Bowman (2013) used an anonymous online survey that investigated attitudes toward female masturbation, their reason for it, and emotions following it. Some 765 American women registered for it with 79% under 30. Most did not feel ashamed of masturbating and many felt it sexually empowered them when used for sexual pleasure or to learn about their bodies. A more recent internet study of women's experiences with genital touching, sexual pleasure, and orgasm using a US probability sample of 1,055 women aged from 18 to 94 by Herbenick, Fu, Arter, Sanders, and Dodge (2018) reported that just 18.4% of the women found PVI alone was sufficient for orgasm, 36.5% reported clitoral stimulation was necessary for orgasm during PVI, while an additional 36% indicated that although clitoral stimulation was not needed their orgasms felt better if it was undertaken during PVI. Accompanying this advocacy for clitoral stimulation are the findings of Suschinsky and Chivers (2018) who reported that orgasm consistency (the proportion of sexual acts leading to orgasm) varied with different methods used for arousal; it was highest with masturbation while PVI consistency was significantly related to oral sex and masturbation consistency. Similar findings about clitoral stimulation during coitus were found by Shirazi, Renfro, Lloyd, and Wallen (2017) using an online sample of 1,478 women and 1,569 men. They assessed how the phrasing of questions about the occurrence of orgasm in coitus could affect the reports by women and men of its frequency. Women's reports of orgasm were the highest to the wording of ‘assisted coitus (concurrent clitoral stimulation)’ (51–60%), second highest with reports of coitus with ‘clitoral stimulation unspecified’ (31–40%) and lowest with ‘unassisted coitus (absence of clitoral stimulation)’ (21–30%). They concluded that clitoral stimulation increased the likelihood of orgasm in coitus. Frederick, John, Garcia and Lloyd (2018) analyzed the sexual behaviors of a large US sample of adults (n = 52,588) which included heterosexual women (n = 24,102). Women were more likely to orgasm if their last sexual scenario included deep kissing, manual genital stimulation, and/or oral sex (both activities would involve clitoral stimulation) in addition to PVI. Interestingly the lesbian women in the group studied (n = 340) were more likely to orgasms than heterosexual women despite not having PVI.

It is interesting to note that Courtois, Alexander, and McLain (2017), in the rehabilitation of women with spinal cord injury, support self-exploration not only of the vulva, vagina, G-spot, cervix, and nipples in regard to assessing their sexual feelings but also clitoral stimulation.

CLITORAL STIMULATION AS A TREATMENT FOR ORGASMIC DYSFUNCTION

Orgasmic dysfunction is the second most common female sexual complaint with incidences of 24% from a random sample of 1,749 US women (Lauman et al. 1994) but a precise estimate of its world-wide incidence is not available because of idiosyncratic definitions of orgasm and a lack of well-controlled studies (see McCool et al., 2014 for criticisms of previous studies and reviews). Many published treatments for female orgasmic dysfunction rely on the use of clitoral self-stimulation, usually referred to in the literature as ‘Directed Masturbation’ (DM) (see reviews by Andersen 1983; Heiman and LoPiccolo, 1988; Meston et al., 2004; Laan et al., 2013; Redelman, 2017). Lopicolo and Lobitz (1972) were the first to develop and publish a successful 9-step programme using DM for the treatment of female anorgasmia. Kohlenberg (1974) found that DM was effective in treating three females regarded as difficult cases that did not progress to orgasm from a previous treatment regime, but with DM they became orgasmic during coitus with their husbands. Barbach (1974), working with primary orgasmic dysfunctional women, used masturbation exercises conducted at home and then discussed their experiences in group therapy. Riley and Riley (1978) employed a programme of DM to successfully treat 20 female patients; 90% gained orgasmic capacity while 85% became orgasmic on at least 75% of their coital occasions. Lopiccolo and Stock (1986) used DM to treat anorgasmia; they combined direct clitoral stimulation during coitus which improved the rate for coital orgasm by 40%. Cognitive behavioral treatment (CBT) using sensate focus, systemic desensitisation and DM reported success rates of up to 90% (Meston and Frohlich, 2001; Heiman and Meston, 1997). Hurlbert and Apt (1995), using a nonclinical population of married women, compared the efficacy of the DM technique (n = 17 women) against the ‘coital alignment technique (CAT) (n = 19 women) to enhance orgasmic consistency during coitus. While CAT yielded ‘somewhat more positive outcome’ than DM in ‘instances where differences in workshop were discovered’ their conclusion, however, was that combining the two treatment modes would prove more beneficial than either alone' a conclusion not surprisingly overlooked by Brody, Costa, and Hess (2013) in their criticism of the use of DM. In their review of women's orgasm Meston, Levin, Hull et al. (2004) listed 10 studies (1976–87) that utilized DM in treating orgasmic dysfunction and all but one registered positive outcome of orgasmic frequency with their sexual partner. Despite all these published successes using DM, Brody et al., (2013) especially criticize treatments using clitoral stimulation (DM) supported in the review by Laan et al., (2013). Brody et al. (2013) and Brody (2017) promote CAT uncritically as the coital treatment for the condition that they claim avoids clitoral stimulation. This technique, and what it actually stimulates, is discussed critically in the next sections.

THE COITAL ALIGNMENT TECHNIQUE—WHAT ANATOMICAL STRUCTURES DOES IT STIMULATE?

Although some aspects of the coital alignment technique (CAT) technique were dealt with in previous reviews (Levin 2012, 2014), the detailed understanding of exactly what female genital anatomy it stimulates is of crucial importance when comparing it with ‘normal coitus’. The history of the development of CAT by Edward Eichel for the induction of the female orgasm by coitus alone is well-documented and accompanied by a series of descriptive diagrams of the essential apposition of the male and female genitals and their movements by Eichel and Nobile (1992) in their nonrefereed, popular book ‘The Perfect Fit’ from its beginnings to the subsequent refereed publication of Eichel, Eichel, and Kule (1988). In essence, CAT is a variant of the missionary position where the male assumes a ‘riding high ‘position by placing his pelvic area over that of the female so that the base of the penile shaft is continuously pressed up against the female's clitoral area and the couple coordinate their limited pelvic up-and-down movements. It should be noted that in the original experimental group conducted by Eichel the attending couples learned the technique within a 2 year psychotherapy programme. Eichel (2000) explicitly notes that ‘coital anorgasmia for women is the consequence of inadequate genital stimulation in coitus, and is not rooted in psychogenic pathology for most women’. Thus he did not classify such women as ‘sexually dysfunctional’. Since the publications of Eichel et al. (1988) and the later overview of the technique by Pierce (2000) in five studies, some clarification in the functional anatomy and physiology of the female genitalia have occurred that shine a new light on the manner by which the penis can possibly stimulate the female genitalia during CAT.

Below the clitoris and surrounding the urethral meatus is an approximate triangular area of mucous membrane (corpus spongiosum) which continues down to its rim of the vaginal introitus (caruncle). Sevely (1987) redesignated this area of the introitus (which previously had no specific anatomical name) as the ‘female glans’ comparing it to that of the male glans and mentioned that it is mobile and could be pushed into the vagina during penile thrusting. Levin (1991) renamed it as the ‘periurethral glans’ in order to avoid confusion with the established described clitoral glans and examined its behavior during actual coital thrusting, observing and recording that it was pushed into and pulled out of the vagina by the penile shaft. The erotic sensitivity of this area around the urinary meatus was noted previously by Kinsey et al. (1953) who mentioned that ‘the area surrounding the meatus is supplied in some individuals with an accumulation of nerves. Consequently direct stimulation of the meatus sometimes included in potential erotic stimulation masturbatory procedures.’ Despite these facts, the importance of the stimulation of this area by the penis during coitus has been repeatedly overlooked, yet it offers a simple and plausible explanation as to why some women are easily orgasmic from PVI alone if their periurethral glans is well-endowed with neural innervation or they are more sensitive to its stimulation or both (Levin, 1992). It is interesting to note that the erotic stimulating potential of the periurethral glans has never been mentioned or included by Brody et al. as an erotic site for stimulation during PVI in any of their published papers. Eichel (1999), however, admitted that in characterizing the female genital activation during CAT, he had overlooked the stimulation of the urethra that occurs in the alignment of the penis with the vaginal introitus. In an article given to the World Congress of Sexology in 2000 he detailed the specific aspects of the urethra that he proposed was stimulated by the penis during CAT. It was the urethral meatus because it was an important site of female prostatic tissue according to Zaviacic (1987). Although Sevely's book was published in 1987, Eichel clearly was unaware of the erotic potential of the whole of the periurethral glans. Even currently there is an obvious disregard of the importance of the periurethral glans in sexual arousal by anatomists who regard it simply as part of the vaginal introitus together with the labia minora and thus not worth special focus or nomenclature. The reader will not be surprised that I disagree!

THE ‘UPS’ AND ‘DOWNS’ OF CAT

The extremely limited, but coordinated/synchronization of the up-and-down male and female pelvic movements in CAT, recommended not to be greater than about 2 inches or 5 cms by Eichel and Nobile (1992, p.128), is claimed to be of fundamental importance to the success of the orgasm-inducing technique. This movement is completely different to the extensive thrusting of the penis in the vagina of a relatively immobile female usually accomplished during ‘normal’ coitus. What suggested explanations are there to make this claim? Wolf (1999−2001) quotes Eichel as claiming that ‘We are now talking about vibration, not friction. Less in-and-out and more rock-n-roll’. What exactly this means is more than problematical. Perhaps we should talk about the co-ordinated ‘ups- and-downs’ of CAT rather than its ‘ins-and-outs’.

Some authors have suggested that repetitive movements of the body (penis/periurethral glans/clitoris/labia) can synchronize brain rhythms through entrainment leading to a pleasurable aroused state via neural oscillating systems (neural resonance) that when critical thresholds are surpassed can precipitate orgasm (Safron, 2016). Safron believes that ‘rhythms are central for the understanding of orgasm’ (see also Komisaruk and Whipple, 2011). Another possible, but overlooked, feature of CAT is the proposed reflex links between the glans clitoris and the vagina, uterus and pelvic floor muscles described by Shafik (1995). He recorded changes in the pressure of the uterus and vagina and an increased EMG activity in the pelvic floor muscles (levator ani, puborectalis) indicating functional activity in the muscles by this named ‘clitoromotor reflex’ while Shafik, El-Subai, and Shafik (2008) later reported that when the clitoris was stimulated (again mechanically or electrically) the vagina showed evidence of electrical and pressure activity, indicating increased contractions. Anaesthetizing either the clitoris or the vagina blocked the responses. The reflex was named the ‘clitorovaginal reflex’. Thus, during CAT, it is also possible that these reflexes are activated, creating functional changes that may well enhance the arousal of the woman facilitating her arousal and the onset of orgasm.

Brody and Weiss (2010) have stated that so-called vaginal orgasms induced by PVI are more easily created by a greater than average penis length and deep coital thrusting (Costa and Brody, 2014) in order to buffet and stimulate the cervix. An alternative explanation was proposed by Levin (2012, 2014) given that during sexual arousal the cervix is elevated away from the thrusting penis and that the organ is known to have very poor sensory innervation, namely, that such deep male thrusting causes increased intermittent pressure from the male pubis on the clitoral/periurethral area further increasing its erotic stimulation. It should now be apparent that in CAT the penis shaft is placed shallowly in the introitus of the vagina up against the clitoris glans and the periurethral glans while the male and female genital movements are inimical to any such deep thrusting. Thus their ardent promotion of CAT to facilitate PVI induced orgasm consistency (Brody and Costa, 2008; Brody 2017) clearly does not accord with their own best practice advice to obtain such orgasm consistency. Furthermore, in another Czech women study by Brody, Klapilova, and Krejčová (2013), it was stated that vaginal orgasmic consistency was not obtained from shallow or middle vaginal stimulation but from deep vaginal stimulation clearly appearing to confirm that CAT would not promote the attainment of PVI vaginal orgasms, an obvious example of being ‘hoisted by your own petard’! Remarkably, Brody and Costa in a previous study (Costa and Brody, 2011) had to admit that ‘the internal structures of the clitoris may have a role in sexual arousal before or during penile-vaginal intercourse’ although they qualified this by stating that ‘PVI is likely to create qualitatively different arousal and orgasm compared to stimulation focussed on the clitoral glans’ yet the latter is exactly what CAT is designed to do. It is well known, but apparently not to Costa and Brody, that few women when stimulating the clitoris actually stimulate the glans directly because it becomes too sensitive and often painful; rather, the stimulation used is along the shaft of the clitoris or manipulation of the hood (Masters and Johnson, 1966). An interesting fact to note is that no study has ever examined women who have undertaken CAT to activate PVI orgasm consistency to see whether they suffer from any of the ‘noxious outcomes’ of its penile clitoral stimulation.

A CLUSTER OF ‘CLITORIDECTOMIES’

In reality none of these clitoridectomies actually facilitate female sexual function.

FINAL THOUGHTS ON CLITORAL STIMULATION

It is apparent that a number of the interpretations, inferences and conclusions of Brody et als.’ papers in regard to the claimed ‘noxious outcomes’ of clitoral stimulation compared to PVI are in serious contention (see also Levin 2012, 2014). Collectively, they appear to be an example of ‘sexual extremism’ in that they vilify or demonize the particular use of one female sexual organ and glorify or over-sanctify that of another. As has been previously commented (Levin, 2014), some aspects of their ‘anti-clitoral’ campaign have similarities to ‘disease mongering’ (Moynihan, 2003). What can clearly be drawn from the literature is the obvious disconnect between Brody et als.’ clitoral concepts and the reality of the actual sexual behavior between men and women initiating a sexual scenario often leading to coitus which rarely excludes clitoral stimulation in its foreplay. Singh, Meyer, Zambarano, and Hurlbert (1998) found, for example, that foreplay (which normally involves clitoral stimulation) increased the rate of orgasm in women. The obvious disparity in the treatment of female orgasmic disorder is clearly seen in two articles in the recently published ‘Textbook of Clinical Sexual Medicine (2017). That by Brody (2017), a psychologist, entitled ‘Evaluation of female orgasmic disorder’ criticizes DM and again proposes CAT as the treatment not involving the clitoris while that by the practicing sex therapist Redelman (2017) entitled 'Treatment of female orgasmic disorder’ recommends DM amongst other treatments.