How Sexual Desire Works- The Enigmatic Urge

by Frederick Toates

  Such questions as ‘how does sexual desire work?’ and ‘how does desire translate into a flow of blood to the genitals?’ have something in common with other ‘how does it work?’ questions. For example, to answer how the blood circulation works under different circumstances, one would need to consider the parts that make up the circulation: the blood, the heart with its chambers and valves and the control that the brain exerts on the heart and the blood vessels. Examining these bits and seeing how they interrelate gives understanding of how the whole works. From this, we might better understand how the circulation can go wrong in the case of, say, a heart attack or how beta-blockers that restrain the activity of the heart or drugs that lower cholesterol work. To see how things can go wrong is a valuable way of understanding how they work normally.

  In a similar way, understanding sexual desire involves consideration of a number of ‘components’ that contribute to desire: the sight of an attractive other individual or the fantasy about them, sexual arousal by the brain, an accelerated heart rate, the anticipation of pleasure, the action of hormones on the brain and signals running both ways between the brain and genitals. How do these act together in creating sexual desire? The present book aims to give some answers. An understanding in such terms can then be used to address differences in desire between individuals, excesses of desire, aberrant desire and how medicine can increase or lower desire.

  Yet, sexual desire is more complex than analogies with the circulation can suggest. It has unique subjective aspects and reflects cultural and historical change, making any understanding extremely challenging. What is an acceptable desire with widespread manifestations in one culture might be a capital offence in another. Although kissing is widely seen as erotic in Europe and America, there are other cultures in which it is absent (Gebhard, 1971). Even in the United States, deep kissing tends to be shunned by the so-called ‘lower-level male’; at least it was in 1948 (Kinsey et al., 1948)! So, considering such cross-cultural differences, it appears that the sexually maturing body emerges with certain potentials for attributing desire to particular bodily regions and behaviours and which of these are realized depends in large part upon learning and culture.

  Curiously, the reasons why people have sex have not been widely researched, except in recent years (Meston and Buss, 2007). Much research on the motivational basis of sex is based upon rats. For humans, there is a mass of information on sexual behaviour and bodily arousal both in the popular and academic literature; indeed, it must be one of the most described subjects of all time. However, the desire that underlies this behaviour earns not even a single index entry in the classic texts of Kinsey on the sexual behaviour of the human male and female (Kinsey et al., 1948, 1953). Equally curious is the observation that sexual pleasure has not played a large role in the history of sexology and does not even earn as much as an index entry in some of the classical texts (discussed by Abramson and Pinkerton, 1995), though one might have thought that it would be fundamental. It earns a single entry in the Kinsey study on the male (Kinsey et al., 1948) but none on the study of the female (Kinsey et al., 1953). This might be a hangover from Victorian prudery and shyness, though such writers as Casanova and Walter would appear to bear witness to pleasure’s centrality. The present book will discuss the role of pleasure in how desire works, as well as considering the vagaries of how pleasure is sought.

  An endless variety

  Yes, sometimes I’ll have desire and not necessarily want to consummate it.

  (Norma, 40-year-old woman; Brotto et al., 2009)2

  Anyone investigating sexual desire soon confronts a dilemma: can you meaningfully study it in isolation? In one regard you have to, since, even with such simplification, it is hard to understand. However, investigators need to remember the multiple goals that people try to juggle, attain simultaneously, blend or pit against each other. These include a search for improved self-image, short-term excitement or long-term attachment. In some cases, sexual desire doubtless merges with an extraneous goal, whereas at other times one can imagine that sexual behaviour is purely instrumental to another goal and there need be little sexual desire present. Some experience sexual desire but inhibit it in the interests of such goals as safety, celibacy, fidelity, maintaining professional etiquette or keeping an image. Understanding the sources of such restraint can tell us much.

  ‘Low-level’ factors such as a magnetic pull of sexual attraction, which probably have much in common across species, co-exist with some high-level goals, such as to seek marital harmony. Some motives seem idiosyncratic and perhaps the only way of getting access to them is to ask the one having the desire. These goals are mediated by more recently evolved brain regions and can be consciously articulated.

  According to self-reports based upon people’s own conscious insights into their desires, the reasons for having sexual behaviour include to feel wanted and desired, to be accepted into a gang, to gain promotion, simply to please a partner, to appease a partner or to infuriate and punish a partner, to come nearer to God or to move away from God, out of a sense of adventure or to boost flagging self-esteem, to assume status in the eyes of others or to look bad in the eyes of others, to relieve boredom, loneliness, headaches, depression, anxiety or insomnia. The list is indeed already a long one (Cooper et al., 2006; Meston and Buss, 2007; 2009; Tuzin, 1995).

  Motives can be roughly categorized into (a) those that involve gain (e.g. feeling more confident as a person) and (b) those that produce escape from aversion (e.g. fear of losing a partner). The expectation of pure sexual pleasure might or might not interact with such goals and it might or might not be attained.

  Researchers conduct surveys in which they ask those who are willing to reveal how their own sexual desire feels, when it occurs, who and what incites or kills it, and what they tend to do about it, if anything. Of course, many individuals would be more prepared to disclose their innermost secrets to an anonymous Internet-based questionnaire than in the form of a face-to-face account. Using this method, people are good at describing what sexual desire feels like and the circumstances that trigger, inhibit or dampen it.

  A landmark study was performed by Meston and Buss (2007), as published in their article ‘Why humans have sex’ and their book entitled Why Women Have Sex (Meston and Buss, 2009). It revealed great complexity of motives and many surprises. My hunch is that a comparable book entitled Why Men Have Sex would be considerably shorter.

  The research revealed 237 different reasons given for having sex. These ranged from the most obvious, such as to obtain pleasure or babies, to the unbelievably obscure and Machiavellian. This section gives a sample of some of the reasons reported to Meston and Buss and other researchers.

  Gaining control

  A feature of not only human make-up but that of many non-human species too is the motivation to exert control over the environment, including the social environment. Sexual behaviour offers a potent means of doing so.

  I was suffering with bulimia. I was having serious control issues and it felt good to me at the time to have complete sexual control over someone, especially a man.

  (Heterosexual woman, aged 23; Meston and Buss, 2009, p. 206)

  I had sex with a couple of guys because I felt sorry for them…I felt power over them, like they were weaklings under me and I was in control. It boosted my confidence to be the teacher in the situation and made me feel more desirable.

  (Heterosexual woman aged 25; Meston and Buss, 2009, p. 206)

  Maintaining self-image

  Humans appear to have a need to maintain a certain self-image (Baumeister and Vohs, 2001). For some, this is of such intensity that the expression ‘narcissistic’ is applied. Earning the admiration of sex partners, finding reciprocity in flirting or even achieving some degree of sexual competence in the eyes of peers must surely contribute to sexual desire. People tend also to be motivated to seek a self-identity such that they stand out from the mass of humanity (Berger and Shiv, 2011). This is manifest in such
activities as buying clothes that are distinctive and presumably some people seek a sexual identity that equally gives them distinction. As the English comedian Russell Brand is witness (Brand, 2007, p. 112): ‘For me, it was more important that people knew I was having sex than having sex.’

  The search for perfection

  The capacity to imagine worlds beyond one’s actual reality means that humans are very good at thinking of sexual scenarios that they are not currently experiencing. The disparity between reality and what can be imagined can set them off on a search for the elusive perfect experience, involving some escalation of their activities (C. Wilson, 1988). Part of the problem is the tendency to satiate on constant levels of stimulation; what was novel yesterday is familiar today, a phenomenon termed ‘habituation’. The perfect solution is often one characterized by high arousal, described shortly, and a dimension of the forbidden (C. Wilson, 1988).

  Producing children

  Some feel sexual desire for the conscious intention of producing children, but this motive appeared not to come very high on the list presented by Meston and Buss. In principle, evolutionary processes might have taken a different direction and created a strong desire for children as the means of transmitting genes. This is not how it has turned out. Rather, evolutionary processes have produced a strong desire for sex, which, unless the situation is artificially manipulated, tends, with some probability, to produce children! The conscious desire for children is presumably a peculiarly human feature, added on to the basic desire process at a late stage of evolution.

  Avoiding pain, distress and discomfort or relationship difficulties

  Desire can arise since it has relieved physical or psychological distress in the past. A significant percentage of males report increased interest in sex at times of depression or anxiety, reporting that sex, particularly masturbation, lowered their level of negative emotion (Janssen and Bancroft, 2007).

  The physical pleasure of sex is one of the best ways for me to relieve menstrual cramping. I’ve had sex for this reason many times as a comfort-based motivation.

  (Heterosexual woman of 47 years; Meston and Buss, 2009, p. 239)

  Many times, in most of my long term relationships, I have had sex because I felt that to go for too long without sex would risk having my partner leave or go somewhere else for sex.

  (Heterosexual woman of 33 years; Meston and Buss, 2009, p. 110)

  For some, sexual desire is weak or non-existent but, nonetheless, they force themselves to engage in sexual behaviour, another feature of how human motivation is organized.

  My sex drive is really pathetic so sometimes I push myself to have sex now and then even though I’m almost never in the mood.

  (Predominantly heterosexual woman of 27 years; Meston and Buss, 2009, p. 120)

  Sometimes, it was easier to just give in and do it when he wanted to rather than put up with listening to him whine and complain.

  (Heterosexual woman of 29 years; Meston and Buss 2009, p. 118)

  Revenge

  Occasionally, a truly ulterior motive exists.

  I decided that I wanted to sleep with this man, just to sort of get back at my friend, and to sort of prove that I was the more attractive/better one of us.

  (Heterosexual woman of 22 years; Meston and Buss, 2009, p. 91)

  I didn’t find the woman I had sex with to make her jealous [to be] attractive and would not have had sex with her if I had not felt I had something to prove.

  (Gay/lesbian woman of 21 years; Meston and Buss, 2009, p. 101)

  So, what is a suitable framework for understanding such complexity?

  Culture and biology

  Avoiding false dichotomies

  For too long, arguments have raged over whether social influences or biology can best explain sexuality, including its diversity. Expressed in other terms – is human desire more a social or biological phenomenon? This discussion is unproductive and will be actively avoided. A modern understanding of brain–environment interaction reveals that these influences are intertwined in such a way that it is meaningless to give relative weights to them. Changes in desire and behaviour might result from initial changes in either culture or an individual human’s biology but invariably we must take both into account. Any viable attempt to understand sexual desire will need to tackle this complexity head-on.

  It is amazing that false dichotomies such as ‘biology versus social’ have endured for so long, fuelled by competition in academia. As Tolman and Diamond (2001) argue (p. 34):

  We maintain that neither a purely biological nor a purely sociocultural approach can encompass the complexity of sexual desire and thus neither is fully satisfying on its own.

  They continue (p. 34):

  This seems so commonsensical as to hardly merit discussion – who could argue with studying culture and biology instead of culture or biology? Yet this is not the impression one would gain from the contemporary empirical literature on gender and sexuality.

  The kind of evidence

  The enormous range in the forms of human sexual desire and the intensities of its expression across cultures and between individuals might appear to support the notion that social and cultural factors predominantly account for it. This is unlike the behaviour of non-humans. However, it does not undermine the importance of biology in explaining human sexuality. The fact that most people are heterosexual and attracted to mature adults doubtless owes something to cultural norms and expectations. However, the tendency would appear to be rather too universal to be simply due to that. It seems reasonable to speculate that culture mirrors biological tendency in this regard. Although such strong tendencies to conventionality emerge, because the human brain has evolved with a powerful general capacity for flexibility, learning and creativity, many different pathways to gaining sexual pleasure are also available.

  The brain mechanisms underlying the flexibility and diversity of human behaviour co-exist and intermesh with some rather fixed brain structures that are somewhat similar comparing different species (Panksepp, 1998). The evidence to be reviewed later will suggest that the biological bases of sexual desire, whether gay, bisexual or straight, whether directed straightforwardly to humans or fetishes, whether legal or illegal, whether social or solitary, show certain similarities in terms of basic mechanisms of desire, arousal and pleasure. Inhibitory processes to varying degrees of intensity and effectiveness also seem to apply throughout. It appears that many, if not all, forms of desire can become addictive, reflecting, I would suggest, the common feature that the mechanisms of desire can move behaviour out of kilter with ideal wishes.

  The group membership of an individual has a powerful role in his or her sexual behaviour (Henslin, 1971). Consider some differences that are evident over periods of time, such as why one decade is more permissive than another. While not ignoring the biology, an explanation would most likely need to focus initially upon changes in culture over time, rather than to try to find changes in biology as the instigator (Udry, 1995). However, cultures can surely exert little influence on desire and behaviour except by acting via a biological organ, the brain. Brains are at the physical basis of desire and they make some of its forms much more likely than others. Irrespective of the culture, brains are the embodiment of the control of sexual action, excitation, inhibition and pleasure.

  People’s sexuality tends to tap into cultural stereotypes, social norms and roles. However, some individuals do not invariably follow the conventions, rules and expectations that could be most effortlessly absorbed from their social context. If things were straightforward, we would not expect to find so many sexually abusive parents, terrified and guilt-ridden masturbators, defrocked priests, disowned and even imprisoned homosexuals, banished daughters and executed adulteresses. The tally is a long and depressing one that cuts across cultures and predilections and it surely bears witness to the power of the discovery of sources of desire and pleasure not entirely restrained by social convention.

  Within a giv
en culture, there exist subcultures often suggesting different standards from the conventional as their social norm. For example, in violent pornography, the portrayal of women as sex objects and suitable fodder for violent male fantasies has probably much to answer for in terms of sexual harassment and assault. It is insightful to consider the conditions that set desire in a direction that conforms or does not conform to cultural norms, values and stereotypes.

  So much for the cultural factor, now consider a given society and point in time and focus upon biological differences. As Bancroft (2000, p. 191) observes:

  We must take the individual biological variability into account when striving to explain the fact that in a given cultural setting, individuals vary considerably in the extent to which they conform to the cultural pattern.

  Differences in sexual behaviour between individuals appear to arise in part from genetic differences, which are mediated via differences in their brains (Ellis, 1989; Udry, 1995). For example, differences in novelty-seeking seem to be explicable in part on the basis of genetic differences. Similarly, within a particular individual, certain chemical changes (specifically elevated levels of dopamine3) in the brain, as in some treatments for Parkinson’s disease, can amplify sexual desire to the point of addiction and can unmask new features of desire (Politis et al., 2013). In trying to understand this, the focus would be upon changes in the individual’s brain caused by the drug. However, the changed behaviour necessarily depends upon the possibilities offered by the particular social context, and will surely further change this context.