Evidence suggests that general arousal triggered by a range of non-sexual events can sometimes spill over into sexual arousal. The chapter will address the issue of the relationship between sexual arousal and sexual desire. The chapter will consider first ‘general arousal’ and then more specifically ‘sexual arousal’.

Basic principles

Some environments are said to be arousing, even some colours are given this description, while other colours are described as relaxing (Apter, 2007). When humans seek to increase arousal, to find excitement, they might go to a busy part of town or engage in a challenging and even dangerous activity. By contrast, to decrease arousal, they might lie on a tranquil beach. Such observations lead to the notion of an optimal level of arousal and humans can try to bring their actual level towards this optimum. People differ in their optimal levels; one person will commonly seek sources of high arousal, while another will try to avoid them.

The nature of inhibition

The means by which desire is inhibited (‘restrained’) represent an important feature of ‘how desire works’ and will be explored here. St Paul describes one form of conflict: that between the will and desire. Throughout the ages, prohibitions and disapproval of ‘inappropriate desire’ and its expression seem as evident as desire itself.

Social harmony requires that all societies have curbs on sexual behaviour, whether of an aesthetic, legal, cultural, religious or moral nature. Some potential inhibitors of sexual desire, such as public censure, have eased with more relaxed attitudes. However, jealousy, anger and disgust over what are judged to be unacceptable desires in others are still universal. For some, the existence of desire and its inhibition represent proverbial conflict.

Evidence suggests that they might not be quite the sovereign masters that Bentham supposed, though pleasure and pain feature large in any explanation of human sexuality.

Basics

Engaging in sexual behaviour has immediate consequences and these are generally assumed to influence future sexuality in terms of desire and the chances of sexual behaviour being repeated (Bancroft, 2009). Consequences of behaviour that encourage us to repeat the behaviour are known as ‘reinforcers’ (Chapter 2). Conversely, the consequences can be such as to reduce the future tendency to repeat the behaviour, in which case they would be described as ‘punishing’. Viewed in evolutionary terms, reinforcement encourages people to repeat behaviour that has served reproduction, whereas punishment persuades them to resist, stop, take stock of the situation and change behaviour. This chapter looks into the details of these immediate consequences of sexual behaviour and their link to desire.

The phenomena

This chapter examines variations in the form of behaviour, where it is idiosyncratic. Some of these forms are perfectly harmless exaggerations of ‘normal’ desire, as in the above, or where some individuals are sexually excited by particular items of clothing, most usually shoes. However, at the other extreme, some are ‘all-engaging’ and extremely dangerous. One person’s desires are fuelled by coercion and violence, whereas most of us are horrified by this. To most, a reciprocating and empathetic human is essential to sexual desire, but a few seek sex with terrified victims or even corpses. Another’s fantasies are mainly masochistic. Others are drawn to peeping through their neighbours’ windows to glimpse a naked body, whereas some want their own exposed genitals to be displayed. Some of the best known such ‘paraphilias’ these days, such as voyeurism, fetishism and exhibitionism, are apparently little if at all evident in traditional societies (Gebhard (1971). They might arise in societies where people are able to remain anonymous.

How can we understand these outliers of desire? Chapters 18–21 look at various forms of desire ‘at the fringes’ and the kind of underlying processes that appear to give rise to them. I cannot provide definitive answers to why someone exhibits a particular ‘fringe desire’, but there are now some strong pointers. The incentive-based model developed in Chapter 4 can serve as a framework for understanding.

Basics

The use of representations of aspects of life is part of what it is to be human (Byrne and Osland, 2000). Representations exist outside the brain on film and paper and in its inner workings of fantasy. Our early ancestors left us cave paintings depicting hunting scenes and wild animals. In the period up to 600 bc, Etruscan art was already explicit in its depiction of heterosexual and homosexual activity (Byrne and Osland, 2000). These days we have films, the Internet, television, photographs, novels and paintings to convey other worlds to our imaginations, including those of sexuality and its possibilities.

Representations of sexuality can trigger arousal in the present as well as plans for the future and reflections upon the past. In the absence of a partner, as in masturbation, or even in their presence during sexual activity, people commonly employ ‘virtual’ means of boosting sexual excitation: erotic visual images, stories and the use of pure fantasy in the imagination (Byrne and Osland, 2000).

Attractiveness is, of course, not the same as sexual desire. For example, a heterosexual man might judge another man to be attractive without feeling any sexual desire towards him. In one experiment, heterosexual women did not show a change in pupil size (an index of desire) on viewing an image of a woman whom they described as attractive (Laeng and Falkenberg, 2007). However, an effect seen across cultures is that normally a necessary, though not sufficient, condition for someone to elicit strong sexual wanting is that they would be judged as ‘attractive’ (Ford and Beach, 1951). Physical appearance (‘attractiveness’) is valued highly by both men and women in terms of what triggers desire (Regan and Berscheid, 1999). There is a sex difference in that men tend to find women more attractive than women find men attractive (Istvan et al., 1983).

Features and qualities

The quality of attractiveness is not simply a product of Hollywood and the advertising industry, though doubtless this has a role in promoting certain stereotypes. In experiments, even human infants as young as 2–3 months of age spend more timing looking at those women’s faces which were judged by adults as attractive (Langlois et al., 1990). By 12 months of age, they spend more time interacting with strangers wearing attractive masks as compared to unattractive masks.

Swelling detected at the genitals appears to add to desire arising from the stimulus of a potential partner (Georgiadis et al., 2012) and might even provide the principal stimulus to desire (Laan and Both, 2008). Positive feedback seems to be involved (Mouras et al., 2008); in response to a visual stimulus, desire would contribute to genital arousal and, by means of signals from the genitals to the brain, there would be an amplification of desire.

The bits that make up the whole

Knowledge of the brain bases of desire comes from several sources (Chapter 2):

1. research on non-humans and cautiously extrapolating to humans;

2. looking at changes in the sexual desire of people following brain damage or disease;

3. using neuroimaging to examine activity in the brains of people exposed to erotic images.

Neuroimaging reveals a network of interacting brain regions, parts of which are excited and others of which are inhibited by erotic visual stimuli (Georgiadis et al. 2010; Redouté et al. 2005). Researchers distinguish regions serving some closely related but nonetheless somewhat conceptually distinct roles:

1. to make an initial assessment of the sexual value of the content of the image;

2. to produce a signal that is sent to the genitals to trigger swelling;

3. to receive feedback from the genitals on their arousal – this signal is thought to contribute to the conscious awareness of the state of the body, particularly the dimension of eroticism;

4. to create a motivational signal, having unconscious and conscious aspects, which tends to direct behaviour towards the sexual stimulus – a feature of this is conscious desire.

It would be informative to discover how Damasio’s readers (and indeed mine too) have reacted to this invitation to reflection. If they are like the population sampled by sex researchers, some would find it hard to recall any such lust-filled moments, whereas others would be inundated with recent memories jockeying for occupation of the conscious mind. Some would doubtless find their desire triggered instantly by such parts of the whole as an ankle or leg, whereas a number might find it fuelled by the shoes worn. Others would only be excited slowly by a whole speaking and socially interacting personality.

The enormous variation in the reactivity of human sexual desire is why I use the term ‘enigma’ and is a feature that must be accommodated by any attempt to explain desire’s foundations. What are the implications of this wide spectrum of responses? Is there a healthy norm, while deviations to either side indicate that something is wrong? Accounts by individuals, both famous and not, on their experience of desire are invaluable in understanding how it works and they will be used widely throughout the following pages.

It is time to return to the enigma described in Chapter 1: the enormous range of different sexual desires, varying from the all-consuming, through indifference, to aversion and from cases where romantic bonding is a necessary condition for desire to the extremes of callous violence. It is hoped that the book has enabled this diversity to be better understood in terms of the role of differences in various contributory factors, such as:

• Genetic differences between people, which can be manifest in terms of different contributions to the structure of brain processes underlying desire, arousal and inhibition, as well as differences in hormone levels.

• Different interactions between sexual desire and attachment, drugs and anger/aggression.

• Chance events of an arousal-inducing nature experienced early in development.

• The occurrence of fear-evoking or disgust-evoking situations at any stage of life.

• Different histories of classical conditioning, such that a range of different events can get paired with sexual arousal.

• A variety of events that can reinforce or punish expressions of sexual desire and thereby alter that desire.

• Differences in sociocultural context.

Given this variety of contributory effects, it is not surprising that there is such a range of different desires both in terms of intensity and their target of attraction. Chapter 2 described a number of common features between sex, feeding and drinking. However, Chapter 4 noted a fundamental difference from feeding and drinking, in that these are both necessary for life and they relate to a regulated state of the body inside and outside the brain. Even given the restraint on variation that is imposed by this regulation, the enormous variety of different appetites for food with associated differences in body weight should be noted. It is suggested that a range of environmental and bodily factors play a role here, some probably similar to those involved in the variations in sexual desire.

This chapter looks in more detail at both universal and idiosyncratic features of desire. The contribution of arousal is considered mainly in Chapter 9.

Two principal and closely related themes run through this account of desire:

• Different levels of control underlie desire.

• Some aspects of desire can be understood through the subjective insight of the person having the desire. Other aspects are beyond such insight and can only be studied with the tools of objective science.

So, what exactly triggers sexual desire?

The diversity and richness of sexual desire

At the basic level

Imagine aman walking near a red-light district and suddenly being propositioned. His thoughts and intentions might have been far from the erotic but sexual desire and arousal were instantly created by the invitation. The woman’s physical properties dominate the ‘stimulus-driven’ control of the client’s behaviour. Just one goal, immediate unconditional pleasure, dominates, with little or no emotional empathy, concern for the pleasure of the woman or thought of the future.

On November 19, 1909, Frederick A. Woods, a geneticist at the Massachusetts Institute of Technology (MIT), coined a “new name for a new science.” This he called historiometry, which covers when “the facts of history of a personal nature have been subjected to statistical analysis by some more or less objective method” (p. 703). Woods (1911) later identified historiometry not just as a science but an “exact science” and claimed that the technique was particularly well suited for the scientific “psychology of genius.” In the original article, Woods (1909) also listed a dozen examples of historiometric inquiries that appeared before the method had acquired a formal name. The list included Francis Galton’s (1869) Hereditary genius, Alphonse de Candolle’s (1873) Histoire des sciences et des savants depuis deux siècles, James McKeen Cattell’s (1903) “A statistical study of eminent men,” and Havelock Ellis’ (1904) A study of British genius. Although Wood intended his list to be comprehensive, he actually overlooked the first bona fide historiometric study published by Adolphe Quételet (1835/1968) more than a third of a century before Galton’s (1869) book (cf. Galton, 1865). Of course, Woods’ (1909) bibliography could not possibly encompass examples of historiometric research published in the century or so since the method acquired a name. Even so, among the most notable examples are Lewis M. Terman (1917), Catharine Cox (1926), Edward L. Thorndike (1950), and R. B. Cattell (1963). It is noteworthy that many historiometricians are themselves noteworthy, and some could themselves count as genuine geniuses – but I will not name names.

If historiometry is truly useful in the scientific study of genius, then it must be able to address some of the central questions in the psychology of genius (Simonton, 2009a). Is genius born or made? Is genius generic or domain specific? Is genius isolated or necessarily situated in a sociocultural context? Is genius mad? Because this chapter is part of a volume devoted to creativity and mental illness, it is the last question that I address here. What do historiometric investigations tell us about the relation between genius and madness – and especially the relation between creative genius and madness? But before I can review the main empirical results dealing with this question, I first must give a brief overview of the methods involved.

During his self-narrated journey through Purgatory in Part II of Divine comedy, Dante encounters a fellow poet, Donati Ferese, who ingratiates Dante with the following greeting: “[T]ell me if I see here the one who drew forth the new rhymes, beginning, ‘Ladies who have intellect of Love’?” Dante replies, “I in myself am one who, when Love breathes within me, takes note, and to that measure which he dictates within, I go signifying.” Ferese continues, “O my brother, now I see the knot that held Notary and Guittone and me back on this side of the sweet new style I hear. I see well how your pens follow close behind him who dictates, which with ours certainly did not happen” (Alighieri, 2003, Canto 24, p. 403).

It would be difficult to find in the literary canon a pithier portrayal of the role of inspiration in the creative process. Dante’s description of inspiration conveys its hallmark features – passive evocation (“when Love breathes within me”), transcendent awakening (“I…take note”), and motivation to express the content of the new awareness in concrete form (“I go signifying”). This passage also puts forth a provocative thesis: without inspiration, the writer produces a work of inferior quality. Although not universal, the belief that inspiration plays an important role in the creative process is widely held among writers and other creators (Fehrman, 1980; Harding, 1948). However, scientists traditionally have not invoked the inspiration concept in their theories or investigations of the creative process. In fact, some scientists (e.g., Sawyer, 2006) have portrayed inspiration as an outmoded explanation of creativity, a supernatural account that originated in ancient times and that has been perpetuated by Romantic poets and other creators.