During the course of the 20th century there was increasing evidence of change in women’s expression of their sexuality, both in terms of their age at first sexual experience, which became progressively younger, associated with a substantial increase in premarital sexual intercourse, and in their increasing engagement in sex as a source of pleasure. We are now confronted with a considerable variability in women’s experience of sexual activity and desire for sexual pleasure. A major change of this kind, which has happened fairly consistently across the Western world, and to a more variable extent in other cultures, can only be explained by changes in socio-cultural control, and in this case, lessening of socio-cultural suppression of women’s sexuality.
However, through most of the 20th century, relatively little attention was paid to the causes of sexual problems in women although, as we will see later, a number of studies explored the role of testosterone in women’s sexuality. Since the turn of the century, following the impact of Viagra and other phosphodiesterase-5 inhibitors on male erectile response, attempts have been made to find a “Viagra for women.” The limited success so far may in part result from the lack of consideration of the marked variability in the non-problematic sexuality of women.
It will be difficult to establish a clinically useful conceptualization of women’s sexual problems, and how they should best be treated, until we have a better understanding of the non-problematic variability of women’s sexuality. There has now emerged a genuine interest among sex researchers to increase our understanding in that respect, and to move on from the preceding era in which women’s sexuality and its problems tended to be conceptualized in the same way as for men. Let us review the evidence of such variability, both across women and within women through their life span and second. The evidence considered will be mainly from the Western world. We will start with consideration of two concepts of central importance to our understanding of sexuality in both women and men: sexual arousal and sexual desire.
Sexual desire and sexual arousal
“Sexual desire” is an example of the somewhat arbitrary concepts we use to describe our experiences, reflecting the extent to which these concepts are socially rather than scientifically constructed. Earlier concepts like “libido” and “lust” have given way to “sexual desire.” Sexual arousal is another concept that is more confined to scientific discourse, but is often used in ways that are not clearly defined. We are becoming increasingly aware of a gap between these concepts of sexual experience and how such experiences are manifested in terms of brain action and psychological processes, a challenge that has been particularly emphasized by the advent of functional brain imaging. Thus, among scholars of sexuality, sexual desire and sexual arousal have traditionally been seen as two relatively distinct though related phenomena. As evident in a recent review, whereas this distinction might have some validity when applied to men’s sexual experiences, in studies of women’s sexuality, there is consistent evidence that these two constructs are highly correlated. In qualitative studies, a proportion of women have explicitly stated that they had difficulty differentiating “arousal” from “desire”, although there was no indication that they considered this was a problem.
From our perspective, sexual desire and sexual arousal are overlapping concepts. Sexual arousal is a complex state that involves: information processing of sexual stimuli, involving both automatic (or unconscious) and conscious cognitive mechanisms; incentive motivation, which includes activation of the dopaminergic incentive motivational system involved in a variety of appetitive behaviors; general arousal, or activation of the central arousal system involved in most arousal states (e.g., pleasurable excitement, fear or sexual excitement); and genital response. It is the “genital response” that is the most specifically sexual component of this state although, in the relevant context, the information processing will be focused on sexual stimuli. The interactions between these components are not well understood. The term “sexual desire” can be used to describe a state that has only some of these components (most often, relevant information processing and incentive motivation). The tendency for women to use these two concepts more interchangeably than men may reflect their lesser awareness of genital response, which will be considered further below, and hence their greater emphasis on arousal in a more general sense (e.g., feeling excited).
In an early study of a representative sample of 225 40-year old Danish women, Garde and Lunde (1980) found that 30% of the participants described having little or no spontaneous sexual desire, yet most had no difficulty enjoying and becoming sexually aroused during sexual interaction with their partner. Over the last two decades, there has been much attention to possible gender differences in sexual desire and in particular to the concept of “responsive” or “triggered” desire, with responsive desire considered more common in women than “spontaneous” desire. It was proposed a model of female sexual response, whereby women most frequently engage in sexual activity not because of any intrinsic sexual desire, but from a state of “sexual neutrality,” primarily motivated by non-sexual reasons, such as desire for emotional closeness with a partner. There is some evidence that this model may be more applicable to women with sexual problems than those without sexual problems. Relevant to this issue is the incentive motivation model (ICM), which sees sexual desire as resulting from awareness of sexual arousal or excitement that has already occurred in response to a sexual stimulus, even when the woman is unaware of encountering the stimulus. Both sexual arousal and sexual desire are perceived in this model as responses to a sexually relevant stimulus; internal thoughts or fantasies are considered equivalent to external sexual stimuli in this context. Proponents of the ICM argue that there is no such as thing “spontaneous sexual desire” because “in order for the sexual system to be activated, the brain has to have processed sexual information”. These researchers acknowledge that sexual desire may “feel” spontaneous, but that this is because sexual stimuli are often processed outside of our awareness .
We would suggest that for most women, such as those in Garde and Lunde’s (1980) study, spontaneous sexual desire would mean desire being experienced not as a response to external cues, but as a result of them thinking about sex and finding the thoughts motivating. This can be contrasted with the situation where a woman thinks about her sexual partner, or even sexual interaction with that partner, without experiencing any desire; the thought just passes through her mind without initiating a state of “desire.”
Looked at in this way, we need to consider what determines whether such a thought does or does not have an activating effect. This may not depend on the stimulus, but on the individual’s state of responsiveness at that point in time. This is the distinction that Whalen (1966) made between “arousal” and “arousability.” Various factors, independent of external stimuli, can influence an individual’s arousability i.e. their disposition to respond to sexual cues, including hormonal factors. An example is the effect of testosterone on a man’s arousability; in a hypogonadal state he is markedly less responsive to sexual stimuli. However, in general, and particularly in the case of women, we understand little about the determinants of sexual arousability. Returning to Garde and Lunde’s sample, while 30% of their female participants were not responding to their own thoughts, they were presumably responding to sexual interaction initiated by their partner, eventually if not immediately. This probably involves different determinants of arousability than is the case when responding to thoughts or fantasies. This confronts us with the possibility that women may vary in the pattern of development of arousal they typically experience in a sexual context, and this may be a key factor in the variability of women’s sexuality that we are striving to understand.
The nature of sexual desire – desire for what?
In her recent review on Hypoactive Sexual Desire Disorder, Brotto (2010) highlighted the extent to which the concept of women’s sexual desire has been assessed much as it would be for men, with little or no consideration of how it might be different for women, and furthermore, how it might differ between women.
A comprehensive review of the literature on women’s sexual desire is focused on how little we understand about what is desired. This revealed a striking gap in our understanding of the concept. The term has been used widely without any explicit consideration of what is desired. The implicit assumption is that it is desire for sexual activity or sexual pleasure. But this assumption does not reflect the evidence to date, which suggests that women who feel sexual desire do not always want to have sex. A distinction was made between “desire to be desired,” which does not necessitate sexual interaction (being desired may be rewarding in itself) and “desire to have sex.” Regarding “desire to be desired,” although there is little direct evidence supporting this, qualitative data indicating that many women report that “feeling desired” enhances their arousal would be consistent with this. In the latter case, there may be various reasons for wanting to have sex; they may be relational in a relatively non-sexual way (e.g., when sexual intercourse provides emotional contact). And, more in line with men’s sexual desire, there may be desire for sexual pleasure and perhaps orgasm. Finally, Meana questioned whether, for some women, the experience of sexual desire is in itself rewarding without any translation into sexual action. We are only just starting to explore these fundamental aspects of women’s sexuality.
These issues have implications for how we assess sexual desire in women. To assess sexual interest, researchers have most often asked women about the frequency of sexual thoughts, using the Interviewer Ratings of Sexual Function or daily diaries. In interviewing women about the frequency of sexual thoughts, across a number of studies involving participants of different age groups, two things have been apparent. Firstly, when asked about the frequency of thinking about sex with interest or desire (from “rarely or never” to “at least once a day”), the variability among women is very evident. For example, in a national survey of women in heterosexual relationships, for the past month, 14% answered “daily,” 26% “several times a week,” 31% “once a week,” 21.8% “once or twice.” and 7.2% “never.” Secondly, was observed a tendency for some women to have difficulty answering the question, even when it was carefully defined is meant by sexual interest (e.g., “Apart from the times that your partner approached you wanting to make love, how often have you found yourself thinking about sex with interest or desire? This includes times of just interest, daydreaming, and fantasizing, as well as times of lovemaking”). In a recent qualitative study, Brotto et al. (2009) found that approximately one third of their subjects expressed difficulties in “putting words to how they understand desire”.
More of research is needed to identify markers of women who are testosterone dependent in their sexuality, but we know for sure that dependency exists. Here, as with orgasm, we are dealing with a variant of women’s sexuality that is biologically and possibly genetically determined. The large majority of women will show some evidence of the basic pattern, and smaller proportions will also show evidence of one or more of the super-added components. Once we have a better understanding of these “normal” varieties of women’s sexuality, we will be in a much better position to understand how they can go wrong.