How Sexual Desire Works- The Enigmatic Urge

by Frederick Toates

  Money (1977) suggested that, from puberty, men and women tend to have an ideal ‘turn-on’ fantasy that is persistent and stable for life. However, certain variations on such a theme can occur, corresponding to the phenomenon of escalation that is seen in sexual behaviour. Crepault et al. (1977 p. 269) write:

  eroticism does not require full perfection but a lack of such which ensures its eternal striving to attain such perfection, and fantasy is part and parcel of this striving toward a goal which is always one step removed from reality.

  Suppose that a first or at least early experience of sexual arousal was triggered by a particular event, such as passionate kissing or watching a pornographic movie (Leitenberg and Henning, 1995). A high level of arousal could increase the strength of consolidation of memory. Therefore, this memory is likely to pop back into conscious awareness subsequently. It might occur spontaneously, by triggering from external cues similar to the arousing event or as a directed search of memory done with the goal of finding a fantasy and thereby triggering sexual arousal. Subsequently the fantasy can be ‘cut and pasted’ and enriched to incorporate new features or delete features that are no longer so arousing (e.g. a change of fantasy figure with a change of relationship). Masturbation can be used to consolidate the latest edit, with orgasm acting as a powerful reinforcer of the fantasy, thereby increasing the probability of its reoccurrence. This kind of process can be exemplified as follows.

  The Victorian writer Walter described his first experience of an orgy (Walter, 1995, p. 354):

  I thought of nothing else for a long time. Nothing has ever yet fixed itself in my mind so vividly, so enduringly, except my doings with my first woman, Charlotte.

  Serving in the Second World War, a Scottish man had his first experience of sex in brothels in Asia (McGuire et al., 1965). He was from a strictly religious background and believed that respectable women simply didn’t consent to sex. After getting married, he fantasized that his wife was a prostitute and his potency depended upon such fantasy.

  Sometimes the initial experience that sets the scene for fantasy does not need to be sexually arousing or even perceived to be sexually associated. However, on later reflection in fantasy the event might take a sexual character, which then can be amplified by masturbation (McGuire et al., 1965). An example concerned a Scottish boy who had been seduced when age 15 by a man on a train. He reported being frightened by the incident and shortly afterwards was punished for a sexual advance towards a girl. Later the incident on the train was used as a prop for masturbatory fantasy and subsequently the man developed a homosexual identity. Note that the early incident was not erotic or even pleasant, but it was emotionally potent, which might have facilitated its consolidation in memory and its later conversion to an erotic stimulus.

  Freud and fantasy

  Freud and his followers took a negative view of fantasy (Leitenberg and Henning, 1995), arguing for a so-called ‘compensation model’, sometimes termed a ‘deficiency theory’. According to this, activity in the imaginary world is a correction for sexual deficiency in the real world and thereby reflects unsatisfied wishes. Given the Freudian notion of an internal equilibrium of pressure or energy levels that the individual strives to maintain within limits, it is easy to appreciate how one might arrive at such a view. What is not ‘coming out’ in reality does so in fantasy.

  Contemporary theorists take a very different view from that of Freud, suggesting that not to have sexual fantasy is a sign of something being wrong, indicative of ‘inhibited sexual desire’ (Leitenberg and Henning, 1995). The Diagnostic and Statistical Manual of the American Psychiatric Association (DSM-IV) defines hypoactive sexual desire in terms of the criterion that ‘desire for and fantasy about sexual activity are chronically or recurrently deficient or absent’ (Pfaus, 2009).

  People scoring high on sexual guilt and negative attitudes to sex score low on sexual fantasy frequency. Sex therapists encourage non-orgasmic women to employ fantasy during masturbation and intercourse (Leitenberg and Henning, 1995).

  A contemporary incentive perspective

  In incentive terms, human and non-human animals are pulled to sexual incentives and, in addition, we humans uniquely (?) can be ‘pulled’ in our world of fantasy. Evidence suggests that the brain processes underlying desire for a physically present individual have overlap with those underlying fantasy about the individual. Thus, sensitization of these common processes by, for example, hormones is reflected in enhanced desire for sexual activity and increased fantasy. Conversely, lack of interest tends to be reflected in low or absent fantasy. So, fantasy reflects reality, actual and desired.

  As noted in Chapter 14, a sample of children first recognized the appearance of a sexual attraction, whether heterosexual or homosexual, at around the age of 10 years (McClintock and Herdt, 1996). Fantasy corresponding to their sexual orientation appeared about a year and a half later and actual orientation-specific sexual contact at around 13–15 years of age.

  There is no evidence of a deprivation effect on fantasy; absence of sexual outlet does not increase the frequency of sexual thoughts (Leitenberg and Henning, 1995). If anything, fantasy frequency increases in parallel with sexual activity. The lack of a deprivation effect is unlike hunger, where there is an increased frequency of food-related thoughts with food deprivation. The lack of a deprivation effect is not surprising on the basis of incentive principles. A short-term deprivation might initially lead to increased sensitization of fantasy, as it does with desire and male ability. However, beyond this short time sexual activity, real, in the immediate past or in prospect, contributes to sensitization of fantasy and thereby increased frequency.

  In one sample of women, the earlier the age they started masturbation, the more frequent were their sexual fantasies as adults (Crepault et al., 1977). A life-time absence of masturbation was associated with a low frequency of fantasies. People who show the highest sexual activity, most frequent orgasms and the fewest problems experience the most sexual fantasies (Gosselin and Wilson, 1980; Jones and Barlow, 1990; Leitenberg and Henning, 1995; Shope, 1971). Those with the greatest variety of sexual experiences similarly have the greatest variety of sexual fantasies. In other words, a high desire and high arousability of desire circuitry is also reflected in an active fantasy life (Gosselin and Wilson, 1980). Women from the late twenties up to the time of menopause tend to exhibit a heightened sexual sensitivity, relative to both younger and older women (Easton et al., 2010). This is indexed by their frequency of sexual fantasies and such things as willingness to engage in sex after knowing a man for a short period of time.

  The direction of what causes what could go either way: actual sexual activity could sensitize fantasy or fantasy could lead to increased activity, discussed next. Most likely both of these things occur in parallel.

  Have fantasies a role in behaviour?

  Intuitively, one might suppose that what a person entertains repeatedly in fantasy, often accompanied by masturbation, corresponds to what, given the chance, they would tend to put into practice in reality. Of course, out of fear, shame or guilt, some might be inhibited in putting their fantasies into effect and would see them as pure fantasy. Others might wish to put their fantasies into effect but lack a willing partner.

  Suppose that it was known that, for an individual performing a particular sexual action, this had been preceded by extensive corresponding sexual fantasy over weeks or years. This would not prove that the fantasy played a role in causing the behaviour. As every psychology student soon learns, correlation does not prove causation. So, are fantasies mere incidental by-products of brain activity (‘epiphenomena’), having no impact on actual behaviour? In principle, this is possible. Alternatively, does the fantasy make a contribution to later behaviour? This contribution might act in either direction. Does a history of fantasy about something increase or decrease the chances of putting the fantasy into effect if the opportunity arises?

  There is little direct evidence on sexual behaviou
r, so we are forced to speculate, based upon other behaviour, where the evidence suggests that fantasy can alter subsequent behaviour. Practising a skill in the conscious mind can improve its subsequent performance in reality (Baumeister et al., 2011). This is particularly likely to be so at the start of acquiring a new skill, before it has become automatic. Fantasy can take the form of rehearsing plans of the kind, ‘if I encounter situation X, do Y’. Subsequently, encountering situation X, behaviour Y is more likely to occur as a result of the mental practice.

  One report suggests that triggering an increase in sexual fantasy can have an excitatory effect on subsequent sexual behaviour (Eisenman, 1982). Students had their sexual fantasy primed by being read an erotic passage and then they were asked to generate their own extensive fantasies and to write them down. In the immediately following period of days, an increased frequency of sexual activity was reported, though with no new sexual variations appearing in the repertoire.

  Another report suggested that certain types of fantasy, which concern future negative emotion, can have an inhibitory effect on subsequent sexually linked behaviour (Richard et al., 1996, cited by Baumeister et al., 2011). Participants were asked to consider how they might feel after practising unsafe sex and this was associated with a lower risk of performing unsafe sex.

  The possible role of fantasy assumes a particular importance when it concerns illegal sexual activity (Chapters 20 and 21). Many people who commit sex crimes report a prior phase of fantasy (Leitenberg and Henning, 1995), and the assumption is commonly made that repeated fantasy contributes to the corresponding action. However, as just noted, correlation does not prove that the fantasy had any effect on behaviour. In principle at least, it might have had no effect at all or it might have served for at least some of the time as a safety-valve. It might even have two effects acting in the opposite direction in the same person: a very short-term satiety effect as a result of its association with masturbation but a long-term sensitization effect.

  Not all sex offenders report a prior history of fantasy. A caution needs reiterating here: we only have the word of the offenders and, of course, they are likely to be more motivated to create the right impression rather than to contribute to psychological research. A contrite account that attributes their behaviour to, say, an unexpected and chance moment of madness while stressed and intoxicated could well go down better with a parole board than would the confession of an extensive prior history of deviant fantasy. So, the figures might underestimate the frequency of prior fantasy in offenders.

  Some insights into the possible role of fantasy in behaviour might be gained by studying the activity of the brain, discussed next.

  Biological roots

  Evidence on the role of hormones suggests a common incentive process that underlies desire, arousal and fantasy. Thus, hormones have a similar effect on fantasy as they do on sexual behaviour and, in men erectile capacity. The level of testosterone in the blood is a principal determinant of the level of desire and the frequency of sexual fantasies in males and females; as the level rises, so does the frequency of fantasies (Regan and Berscheid, 1999; Leitenberg and Henning, 1995). In men, a drastic lowering of testosterone levels as a consequence of treatment for prostate cancer is followed by a sharp reduction in the intensity of sexual fantasy (Bokhour et al., 2001). Some women are able to achieve orgasm by means of fantasy alone, suggesting brain processes that are common with arousal triggered by sexual contact (Whipple et al., 1992).

  What parts of the brain are involved in sexual fantasy? It is believed that the relatively large cerebral cortex in humans provides the biological basis for the capacity to exploit fantasy in rich and creative ways (Abramson and Pinkerton, 1995). However, other brain regions are doubtless also involved in giving fantasy its emotional and motivational colouring.

  Neuroimaging provides insight into fantasy and its possible link to actual sexual behaviour. Results of experiments on feeding and drug-taking can be cautiously extrapolated to sex. Some of the brain regions most closely associated with the desire to pursue physically present incentives can be identified (Chapter 8). These same regions are also involved in fantasy about them. Craving for drugs such as cocaine is associated with activation of the same brain regions5 as are excited by the sight of drugs (Kilts et al., 2004).

  Reading pleasant stories, as distinct from unpleasant or neutral stories, activates the incentive-related brain regions: the nucleus accumbens and medial prefrontal cortex (Costa et al., 2010). This suggests the possibility of overspill from fantasy to reality, in that excitation of these brain regions triggered during fantasy would make an approach towards actual sexual incentives more likely. This observation also raises the distinct possibility that repeated excitation of these particular brain regions by fantasy could sensitize them so that they have increased responsiveness to actual sexual stimuli. This could make subsequent approach to these incentives more likely.

  Some research into the dynamics of the mind is relevant to the role of fantasy, though it was carried out in the context of politics rather than sex (Westen et al., 2006). It was grounded in what is termed ‘motivated reasoning’. This term refers to the observation that human reasoning is guided not just by rational principles but by the outcomes of the reasoning. The human is motivated to reason in such a way that outcomes maximize pleasure (‘positive affect’) and minimize displeasure (‘negative affect’). This was articulated by Sigmund Freud as the phenomenon of ‘defence’, by means of which people act on their cognitions to seek to avoid psychological distress.

  So, in making a judgement on, say, a statement by a political candidate, a person’s judgement would be guided by both a rational analysis of the content but also by how comfortable the individual is with the outcome of the analysis. Hearing a statement that is at odds with one’s convictions might be expected to activate parts of the brain concerned with emotional processing and this could prompt a search for a so-called exculpatory (‘get-out clause’) cognition that would lower the intensity of the negative emotion.

  Neuroimaging was employed to observe the activity of the brain when politically partisan people were given a sequence: (a) a statement made by their favoured candidate, (b) an apparently incompatible statement and (c) an exculpatory statement (i.e. one that could lower the disparity felt on exposure to statements (a) and (b)).6 Resolution of the conflict by presentation of the exculpatory statement was associated with activation of the ventral striatum, a region containing the nucleus accumbens. The researchers argued that since this brain region is activated by the presentation of conventional rewards such as food, the resolution seen in the study also constitutes a form of reward. There was a parallel lowering of activity in brain regions associated with negative emotion,7 giving thereby, as the researchers express it, a source of double reinforcement. One can speculate that this reinforcement will increase the power of such exculpatory statements to trigger this reward process in the future.

  It is reasonable to extrapolate this to the mental life surrounding sexual desire. The experiment suggests that the outcome of emotionally coloured cognitive reasoning can activate the same brain pathways as conventional rewards. This raises the issue that ‘successful’ resolution of the story-line involved in sexual fantasy could strengthen reward pathways and make it more likely for the fantasy to be enacted in reality. This assumption runs implicitly through the literature on forensic psychology and here lies a possible biological basis. While we are with the subject of exculpatory statements, it is relevant to note that these form the stock-in-trade of sex offenders, both in their intrinsic mental functioning and exchanged with other offenders (described again later). These include ‘you are really doing the child a favour’ and ‘women say no when they mean yes’.

  Sexual dreams

  One dream haunted her almost every night. She dreamed that both were her husbands at once, that both were lavishing caresses on her.…And she was marvelling that it had once seemed impossible to her, was explaini
ng to them, laughing, that this was ever so much simpler, and that now both of them were happy and contented.

  (Tolstoy, 1877/1977, p. 151)

  Dreams are a form of fantasy in that the brain runs simulations of possible scenes in their physical absence. They could reflect a problem-solving exercise – testing out possibilities, however improbable they might be. Explicit sexual dreams appear to be more frequent in males than in females (Ellis and Symons, 1990). The erotic content of dreams tends to correspond with the waking desires and activities of the dreamer, for example heterosexuals tend to have heterosexual encounters in their dreams (Kinsey et al., 1948).

  Freud went to great lengths to describe the coding of the hidden sexual themes of dreams in terms of a non-sexual content. However, Webster (1995) notes the extraordinary fact that Freud does not try to account for dreams that have an explicit sexual theme and often reflect the same fantasies as those entertained in daily life. Kinsey et al., (1953) argue that dreams might represent sexual desires unrestrained by social conventions and inhibitions. Furthermore, they rapidly lead to orgasm in many cases.

  It would seem that over two thousand years before Freud made his counter-intuitive claims, Plato was already much nearer the truth. Plato suggested that dreams expose raw desire lifted from its usual restraints such that all sorts of forbidden partners can be recruited. Consider the following (Plato, Republic, 571c, p. 308):

  ‘But what are the desires you mean?’

  ‘The sort that wake while we sleep, when the reasonable and humane part of us is asleep and control is relaxed, and our fierce bestial nature, full of food and drink, rouses itself and has its fling and tries to secure its own kind of satisfaction…It doesn’t shrink from attempting intercourse (as it supposes) with a mother or anyone else, man beast or god.’