Motivation and emotion/Book/2017/Testosterone and sexual motivation

Testosterone and sexual motivation:
What are the effects of testosterone on sexual motivation?

Multimedia presentation (3 min)

Overview

Stop, imagine your ideal sexual experience. Think about the time, place and person or object it is with. Does this make you aroused? Is it with a partner? Is it with multiple partners? What preceded this moment? How did you feel then? How do you feel right now?

Chances are that this very thought aroused some changes within you. Have you ever wondered what mechanisms underpin the feeling of sexual arousal and our motivation engage in sexual acts? Humans are wonderful and complex organisms capable of many things.

Testosterone has been found to be a leading physiological cause of sexual motivation. However, primarily perceived as the "male" hormone - does this mean that females don't experience any sexual motivation? Surely this can't be true, so what kinds of individual differences exist in relation to gender, age, relationships status and situational determinants? And what can be done to increase testosterone levels and thus sexual motivation within individuals struggling to find arousal?

These are the types of questions that arise when thinking about the relationship between testosterone and sexual motivation. Someone acting upon their own sexual desires and motivations is what begins the mating effort and so can be considered a fundamental element of survival, and the underlying cause of your very own existence. An elemental question that must be asked is whether there would be any life without sexual motivation. It is because of this importance that research into the motivating factors behind sexual activity has flourished. This chapter provides a broad overview of testosterone as a cause of sexual motivation. The chapter will address some of the aforementioned questions and bring into light other relevant topics of interest inclusive of psychological theories that are often considered to coincide with this biological view of sexual motivation.

Focus questions What is testosterone? What is sexual motivation? What theories underlie sexual motivation? What effect does testosterone have on sexual motivation? Are there groups of people which experience more testosterone and thus sexual motivation?

Case studies

Think about the below cases whilst reading this chapter. Consider how their circumstances impact testosterone levels and sexual motivations and actions

John is a 65 year old man in a committed relationship. John and his wife just celebrated their 35th anniversary. John has been told that he has hypogonadism.

Sarah is a 28 year old single woman. As a national tennis player, Sarah travels a lot and has a large history of sexual partners and expects that list to grow.

Phillip was convicted at the age of 26 for rape and remains in prison. He is now 32 and constantly thinks about the event with lust. He fantasies about having sex with multiple people with no attachments

Testosterone

Figure 1. A 3D animation of a testosterone molecule

Brief overview

Testosterone (T) is a steroid hormone made from cholesterol (see Figure 1) that is secreted by the Testes in men, and the ovaries and adrenal cortex in women (Mehta & Joseph, 2011). As an androgen hormone hormone, T is responsible for development and maintenance of masculine characteristics (Mehta & Joseph, 2011). As a sex hormone, T plays a large role in the development of secondary sexual characteristics in both males by the way of morphological, physiological and behavioural traits (Hau, 2007) and females expressed as weaponry, ornamentation and aggressive behaviour (Kraaijeveld et al., 2007).

Individual differences

T levels in men tend to peak in early adulthood and reduce with age, with the most change occurring before 50 years of age whereby 'normal' levels lower each following decade with a decline in approximately 1.6% per year (Barrett-Connor, 2005). Health and lifestyle factors also impact T levels, and approximately 2.5% of men between 40 and 79 have abnormally low levels (Mohr, Guay, O'Donnell & McKinlay, 2005).

According to the University of Rochester Medical Center (Hanrahan & Sather), normal male T levels are between 280 and 1100 ng/dL and typical female T levels vary, but are generally lower than in men and range from 15-70 ng/dL. If levels are lower than normal, the individual may have a conditions that affect testosterone production and if results are higher, a tumor may be present on the testes or ovaries.

Athleticism has been found to be correlated with increased T levels in both males and females, whereby female elite athletes had almost double the amount of T compared to non-elite athletes (Cook, Crewther & Smith, 2012).

Table 1.

Effects of low testosterone levels in males and females according to University of Rochester

Men	Women
Large breasts	Fertility problems
Low sex drive	Missed or irregular menstrual periods
Difficulty getting erection	Osteoporosis
Low sperm count	Low sex drive
Changes in testicles	Vaginal dryness

Test yourself Where is testosterone produced in females? Testes Brain Ovaries Kidneys Vagina

Sexual motivation

Figure 2. Sexual desire in the bedroom

Brief overview

Motivation is a state of elevated interest in a specific goal, and so sexual motivation revolves around desire to satisfy goals related to sexual behaviour (Hill & Preston, 1996). Sexual motivation is often termed as sexual desire. Hill and Preston (1996) described sexual desire as a non-specific feeling resulting in a self-reported heightened sense of sexual interest. When one experiences sexual desire, they often seek out activities to experience the pleasure associated with completion. Such acts include individual behaviours inclusive of fantasy and masturbation, and coupled behaviours such as kissing, touching, oral sex, intercourse, anal sex and same-sex techniques (Rye & Meaney, 2007). Engagement in sexual activities may not always be the result of sexual motivation. For some, sexual activities can be considered work - ie prostitution or a spousal duty to fulfill partners needs or for reproduction (Rye & Meaney, 2007). In other circumstances, sexual acts may also occur by force or without consent for either the giver and/or receiver - this occurs within sexual assaults and rape (Held & McLaughlin, 2014).

Note Not all sexual activities are physical and can be externally viewed. There is a distinction between desire and action. Activities such as fantasizing are internal thoughts, whereas physically acting out a fantasy would be putting that sexual desire into action.

Individual differences

The pursuit of pleasure underlies sexual behaviour (Meston & Buss, 2007), and thus sexual motivation. People experience pleasure on different levels. A study conducted by Barnett and Melugin (2016) revealed that inexperienced individuals consistently reported less pleasure to sexual behaviour than experienced individuals in a study of 15 sexual activities. Results also concluded that age, ethnicity and relationship status to be predictors of sexual pleasure. Melugin and Barnett (2016) describe results from previous studies that explore gender differences in sexual pleasure. Results frequently detail that men report more enjoyment of sexual behaviours than women, and that women place less emphasis on pleasure and more emphasis on factors such as love for sexual engagement than men.

Many theories of sexual motivation and desire exist, few of which will be discussed in the next section. Theories have evolved throughout the years, originating from a perceived "build-up" and release of sexual energy as assumed by psychoanalysts (Tiefer, 1991) - to a(n) evolutionary/biological viewpoint expressed by Master and Johnson (1966) that posited humans to have an innate drive to orgasm.

Test yourself According to Rye and Meany (2007), sexual acts include all but which of the following Role playing Sexual fantasising Masturbation Kissing Anal sex

Theories of sexual motivation

As the underlying mechanism of human behaviour, a widely studied area in the field of psychology is motivation. Many researchers have theorized and conducted studies to explain motivation and thus behaviour, and consequently multitudes of motivation theories have been proposed. Perhaps among the most well known psychological theories of motivation that can be related back to sexual desire are by Sigmund Freud and Abraham Maslow.

Figure 3. Maslows hierarchy of needs

Freud built upon the work of early motivational theorists in that he suggested motivation arose from a powerful force within the body dubbed 'drive'. Drive can be defined as a change in mood accompanied by an urge to fulfill ones needs (Cotti, 2008) which result in an immense feeling of pleasure and is thus the ultimate determinant of human motivation (Gardner, 2000). "Sexual drive" became a major concept in Freud's' sexual theory in his paper Three essays on the theory of sexuality (1905). Freud identified sexual drive as a biological urge originating within the testicles. In 1895(a) Freud described the libido as the psychical manifestation of bodily sexual excitement which represented the mental component of the drive. Freud (1985b) also stipulated that certain great needs (hunger, breathing and sexuality) produce excitement that the human body cannot escape whereby the individual impulsively engages in activities to fulfill the needs. It has been suggested that sexual drive is stored during childhood and used only as psychical representations, and that expression occurs only after puberty when appropriate physiological mechanisms present (Freud, 1898).

Figure 4. Tanner scale of male secondary sex characteristics development during

Freud's' work also revealed normal sexual motivation as abstract and difficult to accomplish. Deviations from what is considered the 'norm' are prevalent and arise from deviations of object (person/animal/fetish that sexual act is directed) and aim (sexual act that is desired) choice within healthy individuals (Freud, 1905).

Aligning with Freud, Maslow (1936) concluded that sexual behaviour exists on a continuum between 'sexual drive' and 'dominance drive'. In later years, Maslow distinguished love from sex and considered sex as an entirely physiological need (1943). According to his hierarchy of needs (1943) (see Figure 2) physiological needs are the beginning of motivation and assist in homeostasis such as the regulation of hormones. Maslow proposed that before approaching each new level of needs, the needs of the level below must first be fulfilled. If the current level of needs aren't satisfied, all higher needs seem unimportant. Once fulfillment of physiological needs occurs, then safety security needs are attended to, followed by belongingness, self-esteem needs and finally self-actualization. Maslow (1987) defined self-actualization as an individuals desire for self-fulfillment and to become more and more what one's character truly is.

This chapter explores the effect of the hormone testosterone on sexual motivation. As hormones are biological in nature, research investigating the relationship between testosterone and sexual motivation can be said to build upon a biological/physiological theory of sexual motivation. Both Freud and Maslow, to some extent, included biological/physiological underpinnings of sexual motivation within their theories. Freuds' assertion that the testes in men are the origin of sexual motivation parallels to testosterone as a cause of sexual motivation; as the testes produce testosterone (Mehta & Joseph, 2011). Also confirming Freud's statement that sexual drive is inhibited until after puberty, is growing evidence of adolescents which continuously conclude in a growth of the testes and an increase in plasma testosterone after puberty (August, Grumbach & Kaplan, 1972) (see Figure 3). Maslow specifically named sex as a physiological need, coinciding with its physiological basis of testosterone as a modulating factor.

Test yourself Which of the following is not included in Maslows hierarchy of needs? Physiological needs Esteem needs Self-determination Safety needs Belonging needs

Testosterone and sexual motivation

Alongside being responsible for development of key secondary sexual characteristics, recent studies have concluded that satisfactory testosterone levels are necessary for sexual functioning and insufficient levels result in poor sexual health (Miner & Seftel). Testosterone has been found to affect sexual behaviour and be affected by sexual situations and stimuli (van Anders & Watson, 2006). The Steroid/Peptide Theory of Social Bonds persists that competitive contexts such as sexual situations will increase testosterone levels, and in contrast testosterone levels decrease in nurturing contexts such as loving care (van Anders, Goldey & Kuo, 2011). By some researchers, testosterone has been noted to be the main regulator for timing of erections relating to sexual desire within men.

Testosterone deficiency and testosterone replacement therapy

Figure 5. Testosterone replacement therapy by way of intramuscular injection

Classified as primary or secondary hypogonadism, testosterone deficiency has been found to have various effects on human sexual functioning. These effects include reduced libido, erectile dysfunction and decreased volume of ejaculate (Bhasin et al., 2010). Wu and colleagues (2010) also found an association between low testosterone levels and decreased sexual thoughts, sexual desire and morning erections among men. Indirectly associated with sexual motivation is erectile dysfunction. Studies have concluded that although erectile dysfunction is a physical disability, it can often have an impact within couples sexual intimacy leaving individuals dissatisfied sexually - resulting in negative psychosocial side effects pertaining to not achieving sexual pleasure (Beck, Robinson & Carlson, 2013).

To combat the effects of testosterone deficiency, Testosterone Replacement Therapy can be implemented by oral, patch or intramuscular injection methods depending on preference (Jockenhovel 2004) (see Figure 5). Those undergoing treatment do so in hope of improvements in erectile functioning and libido (Bhasin et al., 2010). Mixed results have been found in regard to effectiveness, but studies have found significant results. In 2008, Allan et al., conducted a study with ageing men with generally good health, and low testosterone levels. Treatment individuals received 12 months of treatment whereby comparative to the control condition at the end of the period, elicited improved sexual desire. Similar results showed improvement in erectile functioning with testosterone therapy in combination with PDE5 inhibitors (Avera et al., 2003).

Testosterone and sex crimes

A relationship between testosterone and sex crimes has also been examined. Sex offenders are those that have committed crimes of a sexual nature inclusive of rape and sexual assault. Sex crimes are often violent in nature, and driven by a desire to dominate the victim (Stanford University, 2017). Testosterone has been linked to extreme dominant and aggressive behaviour (Johnson, Leedom & Muhtadie, 2012) and heightened confidence (Carre & McCormick, 2008) - both of which can create a deadly combination with sexual motivation and criminal actions.

In 2003, Ellis proposed the evolutionary and biological theory Evolutionary Neuroandrogenic Theory (ENA) to explain criminality by the means of competition for resources, status and mating. The theory suggests that men are innately competitive, which results in high occurrence of victimizing others inclusive of sexual assault. The theory also stipulates that androgens are the cause for the high level of competitiveness. A prison study conducted by Dabbs and colleagues (1995) concluded that inmates serving time for sexual crimes had significantly higher testosterone than those convicted of crimes such as burglary, theft and drugs. Similary, Studer, Aylwin and Reddon (2005) concluded that men with the highest testosterone levels in a convict sample committed the most invasive and crude sexual crimes. Studers' study also made an association between high testosterone levels and likelihood of recommitting sexual violence.

Impact of sexual stimuli

Sexual arousal can occur and increase testosterone levels even without any behaviour such as masturbation. Work by Goldey and van Anders (2010) revealed that the mere presentation of sexual stimuli by the way of attractive men can increase testosterone levels in women not on a contraceptive pill comparative to control or stressful situations. in 2011, Goldey and van Anders conducted a similar study with men which produced similar results by thinking about women and writing a sexual story. For both studies, higher baseline testosterone levels predicted a larger increased in self-reported arousal.

Testosterone and relationships

Figure 6. Those with multiple partners have high testosterone levels.

The association between testosterone and relationships has also been explored within studies, particularly testosterone level differences between genders and relationship status (single, partnered or multiple partners). Testosterone levels have been found to decrease within nurturing environments, and so it can be thought that high levels of testosterone are incompatible with relationship maintenance (van Anders et al., 2011). Edelstein and colleagues (2014) found a negative relationship between testosterone levels and relationship commitment and satisfaction between both men and women.

In 2010, van Anders & Goldey a study whereby results determined consistent findings that both single men and women had higher testosterone levels than long-term partnered men and women, respectively. This was true for any sexual orientation. Results also found that for men, casual relationships yielded the highest testosterone levels - this was not the case for females; whereby single women had the highest testosterone levels.

Edelstein, Chopik and Kean (2011) assumed that testosterone levels in single individuals are higher because of the increased effort involved in mating, or a desire to find a partner. Their study explored sociosexuality (desire for multiple partners, fantasies, increased sexual behaviour) and testosterone levels within both men and women who were partnered, had multiple partners or were single. Results concluded that partnered men with higher desire for uncommitted sexual activity had testosterone levels similar to single men, alike with women. Men with multiple partners had the highest testosterone levels in, as was the same for women. Overall, those individuals which had higher sociosexual desire were considered to be of unrestricted orientation and had higher testosterone levels than restricted individuals with lower desire for uncommitted sexual activities. Generally, men had more unrestricted desire to act in a sociosexual manner. Although testosterone levels in women are much lower than in men, small differences do have a big impact. Edelsteins' study concluded that testosterone affected men and women in regard to sociosexual domains. For men, testosterone impacted desire to participate, whereas for women the impact was on the behaviour itself. Past and predicted future sexual partners of women were positively correlated with high testosterone levels.

Test yourself According to the study conducted by Dabbs et al. (1995) which group of individuals exhibited the highest testosterone levels? Burgulars Theifs Drug users/dealers Sex offenders None of the above

Case study questions

Providing everything you have read in this chapter, answer the following questions regarding the case studies given at the beginning of the chapter 1 Who would have the highest overall testosterone levels? Phillip John Sarah 2 If Sarah engaged in a closed, committed relationship, would would most likely happen to her testosterone levels and thus, sexual motivation? increase decrease remain the same women don't have testosterone

Conclusion

Testosterone has a multitude of impact on sexual motivation and thus sexual behaviour. Generally, those with increased levels of testosterone exhibit greater sexual desire, and those with a deficiency have a decreased ability to function sexually, are sexually dissatisfied and yield little sexual motivation. Particular individuals have increased testosterone levels. These include men in general, sex offenders, athletes, single individuals, those with multiple partners and those who have desires to engage in multiple uncommitted relationships. Future research would benefit by exploring the LGBTQ community, as little research is currently available on the topic.

Take-home message: We are all sexual beings in one way or another. We exist on a continuum where testosterone is one of the defining players

See also

• How to get more sex (Book chapter, 2013)
• Hormones and motivation (Book chapter, 2017)
• Neurobiology of romantic love (Book chapter, 2015)
• Paraphilia Motivations (Book chapter, 2017)
• Sexual motivation and hormones (Book chapter, 2016)
• Unconscious sources of attraction (Book chapter, 2015)

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External links

• How testosterone affects attraction (Online article on how testosterone affects attraction)
• Lets talk about sex (YouTube video by Crashcourse on sex)
• Sex hormones and womanly passions (Online article in Psychology Today about competition among women with testosterone)
• Testosterone replacement therapy journey (A series of YouTube videos describing a mans testosterone replacement therapy journey)