Motivation and emotion/Book/2023/Testosterone and dominance

Testosterone and dominance:
What is the relationship between testosterone and dominance?

Overview

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Figure 1. Charles Darwin, an English Naturalist who is widely known for his contributions to evolutionary biology.

What propelled Michael Jordan to become the greatest player to ever touch a basketball, or guided Jordan Belfort to the title of the Wolf of Wall Street? What facilitated Katniss Everdeen's road to overthrowing an entire government? What sets them apart from those who reside below, allowed them to dominate, and fuelled the relentless pursuit and maintenance of simply being the best?

Dominance is a trait present in people which describes an individuals[grammar?] drive to pursue power[1]. While animals often establish dominance through physical contests of aggression, the evolution of humanity has spawned distinct avenues for seeking and asserting dominance[2]. Yet, as Charles Darwin (see Figure 1) posited in 1859, the dichotomy between humans and animals is not as stark as once presumed[3]. Over the years, this proposition has sparked and transformed many theories, including Freud's Drive Theory[4] , Hull's Drive Theory[5] and many more.

But what steers us toward dominance motivation? Interestingly, a glimpse within ourselves offers a clue. Hormones orchestrate our emotional landscape, hunger, and even romantic inclinations. Among these, testosterone emerges as a valuable facet, particularly relevant to dominance in humans[6].

Physical mechanisms, in the sense that they are present in the material world (such as hormones), were an important aspect of the then popular neoclassical grand theories. The question then remains: why? Although motivation study has changed direction over the years[7], the brilliant minds of Freud, Darwin and Hull had merit. This chapter explores, identifies, and highlights different aspects of dominance and looks closely into the intersections of motivation, dominance and testosterone, as well as look into 'Traes' [say what?] journey navigating the complex world of hormones and motivation.

Focus questions:

  • What is testosterone and why is it important?
  • What is dominance?
  • Who or what is dominant and why?
  • What is the relationship between testosterone and dominance?
  • Who is affected?

The origins of dominance

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The concept of dominance plays an important role in animal and human behavior. Dominant individuals are seen to achieve greater social influence and resources when compared to individuals displaying less dominance[8]. The mere existence of dominance indicates a tendency for species to form dominance hierarchies. Where entire communities are formed by superiors and subordinates ranking on a continuum[grammar?]. This construct has been observed for millennia and will continue to exist in various human and nonhuman societies.

Imagine you are in a family of 5, and your younger sibling [grammar?] Ethan is almost always taking charge of decision-making. Even though you are older it seems like he is always organising activities and even mediating disputes in the family. You also find that even though you are Ethan’s senior and you guys play football together and follow the same exercise regime, he just seems too always be ahead of you. You reflect on your brother for a little while and come to realise that he is more social, confident, and even physically stronger than you. You get out your computer and google “why is my younger sibling more confident than me?”. You research for a while and come across the term 'dominance '

Dominance in ethology

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Much like Darwin posited in 1859, the separation between man and animal is much less severe than once proposed. In the wild, dominance is present in various domains across many species. These include social hierarchies, dominant and subordinate individuals, and dominance displays. You may be familiar with the term social hierarchies; these are not just limited to the classroom or office but can be found in birds, mammals, and even some insects[9][10]. Among social hierarchies, birds are ranked according to a pecking order, also known as a dominance hierarchy. In 1940, a study was conducted examining the effects of injecting male sex hormone (testosterone) into female ring doves intravenously. Interestingly, the effects of the testosterone transformed a bird that was situated at the bottom of the pecking order (D), to the top[11]. The experiment noted that there were several behavioral changes that resembled 'male' behavior, such as aggression and dominance displays. Moreover, 50 days post injections, D had fallen to second last in the pecking order. At the most basic level, exogenous testosterone can transform an animal from the bottom of its pecking order to the top. Furthermore, what makes this alarming is that, after cessation of testosterone supplementation, the animal returns to its original state at the bottom of the food chain. Which begs the question: how would exogenous testosterone on an individual human affect their navigation through intricate and complex social hierarchies?

 
Figure 2.1. An aggressive and dominant white dove.

What is Testosterone?

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Before we can address the above question, we need to first understand testosterone. Testosterone is an essential hormone that is a part of the physiology of all humans. The hormone is essential for the growth and physical development of males[12]. Although also found in females, the concentration of testosterone in females is around 15-25 times lower than males[13]. Some of the functions of testosterone include bone strength, functioning libido, body hair growth, mood and energy regulation[14], metabolism and fat distribution, cognitive functions and many more[15]. This chapter primarily focuses on the effects of testosterone in males given that it is a male sex hormone.


Hormones

You may have heard of the term hormones but what are they exactly?

Hormones are chemical messengers that affect and manage hundreds of processes in the body. They are complex but, you can try to imagine hormones as keys that circulate throughout the body via the bloodstream. Each key is specifically shaped to fit into a particular lock, which represents a receptor site on the surface of a target cell. When the correct hormone (key) encounters a target cell with the corresponding receptor (lock), it binds to the receptor site, initiating a specific biochemical response within the cell.[factual?]

Just as a key can only fit into a particular lock that matches its shape, hormones can only interact with cells that have the appropriate receptors. This specificity ensures that hormones influence only the cells and tissues that are designed to respond to their signals.[factual?]

Some hormones that you may have heard of include testosterone, insulin, adrenalin, estrogen, ghrelin.

[16]

Types of testosterone

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The role of testosterone varies from person to person because the hormone is present in the body in two different forms; these are free testosterone and basal/total testosterone. Total testosterone is the total amount of testosterone in the human body, including testosterone that is bound to proteins and the "free/ circulating" testosterone. Measurements of basal testosterone are useful as a predictor for morbidity and mortality[17]. On the other hand, free testosterone which is unbound is a much better predictor for testosterone deficiency[18], associated with bone health and fragility and also avoids under/over diagnosis in relation to androgen replacement therapy[19]. With reference to the free hormone hypothesis, bioactivity of a certain hormone is best reflected by free concentrations rather than total[20]. Studies selected for this chapter have been based on measurements of both free testosterone and basal testosterone.

Challenge hypothesis

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Much like other forms of hormonal theories[grammar?]. The challenge hypothesis began in animals, where hormonal levels of animals in captivity were vastly different to wild animals[21]. These observations led to the discovery of temporal spikes of testosterone levels during direct male-male competition. On the other end of the spectrum, testosterone levels are seen to decrease during times of paternal care[22]. Research into the challenge hypothesis has produced highly relevant hypotheses for social interactions among humans, even in the face of new emerging technologies, aggression and dominance [23].The challenge hypothesis is essential for understanding the effects of testosterone in specific contexts.

Dominance motivation

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In motivational psychology, dominance can be broken into two distinct categories; dominance motivation and dominance behavior. On one end, dominance motivation is the underlying reason/s for an individual to be dominant or it can be conceptualized as an individuals[grammar?] drive and energy to pursue power[24]. At a basic level, some purposes of dominance motivation include survival, resource acquisition[25], reproductive success and personal fulfilment[26]. Contrastingly, dominance behavior entails strategies enacted in the service of attaining power[27]. Some dominant behaviors include aggression[28], assertiveness, leadership[29] and social affiliation[30]. Think of dominance motivation as the engine of a car, creating energy and force. Now, imagine cars [grammar?] wheels and how they interact with the road; the wheels represent dominance behavior as they are the outward actions.

Meet Trae

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In [grammar?] current day, many males suffer severe complications due to a naturally occurring decline in testosterone coupled with testosterone deficiency syndrome (TDS)[31]. Symptoms of rapid testosterone decline include lowered functioning of organs[32], decreased libido, hot flashes, depressed mood, loss of muscle and/or hair [33] . To combat this, patients may be given various forms of testosterone replacement therapy (TRT/HRT) [34].

Meet Trae, he is a 45-year-old male accountant who has recently been diagnosed with TDS[35] by his doctor. To aid with his deficiency he has been prescribed 50mg of Androgel (a topical testosterone replacement) to apply on his shoulders, upper arms or abdomen once daily in the morning[36]. The rest of this chapter explores the complex landscape that comes with Traes[grammar?] added testosterone. From elevated hormone levels to changes in physical appearance, behaviors, and social interactions[grammar?]. The case study provides a compelling lens through which we can explore the intricate dynamics at play. It embraces the biopsychosocial framework, considering the influences of biology, psychology, and social context, and seeks to offer a comprehensive understanding of how testosterone shapes dominance and its implications for an individual's well-being.[37]

Biological factors

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Testosterone plays a large role in the development of males during adolescent years[38]. Trae is no teenager but he has noticed that the testosterone has been affecting his body. Trae noticed that his t-shirts are becoming very tight around the sleeves and his chest is looking and feeling fuller. This muscle mass can be attributed to testosterone's pivotal role in stimulating muscle protein synthesis (mps)[39]. The other day Trae noticed that he was getting many compliments on his beard, [grammar?] he thought this was strange since he had not changed his shaving routine. He asks his doctor, who advises him that the increase in testosterone can significantly affect the growth of body hair in people[40]. Although not as dramatic in males, elevated levels of testosterone can also lead to changes in voice pitch[41]. Trae likes feeling much more confident and assertive because he has been enjoying the combination of larger muscles, lowered fatigue, increased libido and social recognition[42].

Psychological factors

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Figure 3. Depicting Trae snapping at his colleague Declan

Trae's journey so far has not been limited to only physical changes but also to a complex interplay with his psyche. Trae's boss Billy has been noticing certain behaviors that are not consistent with who he is historically. For example, over the last week, Billy saw Trae snap at his colleague Declan for not sending through an acquisition form on time (see Figure 3). He thought this to be highly unusual, given that Trae is normally very compassionate and understanding. This may be due to testosterone's ability to increase aggressive behavior[43], which is often described in the context of the "challenge hypothesis"[44]. Billy also recalls receiving an email about Trae's pitch at a meeting (see Figure 4). The email sent to Billy highlights changes in Trae's confidence, assertiveness, and risk-taking. These changes reflect dominance and can potentially be attributed to Trae's added testosterone[45]. Trae is surprised by how rapidly his life is changing. He understands that testosterone may be affecting these changes, but he doesn't understand how or why. The interplay between these psychological factors, influenced by testosterone, is central to understanding how Trae's dominant behaviors manifest. His heightened aggression, assertiveness, and confidence are not isolated traits but rather interconnected facets of his response to elevated testosterone levels[46]. Recognizing this interplay is crucial to comprehending the complexity of dominance-related behaviors in people like Trae.

 
Figure 4. An email from Billy's' supervisor, recognizing Traes outstanding work

Social factors

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Trae's rapidly changing life is not only dictated by his emotional landscape and physical wellbeing but also by the interactions in his social life. After impressing Billy with his supreme work ethic, assertiveness, leadership, and new-found competitiveness[grammar?]. Billy has decided to offer Trae a higher position in the organization. Thereby making Trae more likely to repeat his behaviors[grammar?][47]. An avenue for understanding this behavioral pattern can be attributed to Skinner's operant conditioning learning process. In accordance with the theory, Trae's promotion may act as a reward, which then becomes a positive reinforcer for his behavior[48]. This positive reinforcement results in more confidence, more assertiveness, and more dominance, making Trae more likely to repeat his behaviors, only to be rewarded for them in a seemingly endless feedback loop[49]. Confidence, assertiveness and dominance are highly valued in the competitive industry that Trae works in[50]. The competitiveness of this industry encourages Trae to assert himself more vigorously to secure opportunities for career advancement, as does the hierarchical structure of the industry, adding another factor that promotes Trae's dominance. Another social factor influencing Trae's testosterone-fuelled dominance in the workplace is his personal ambitions. Trae has an innate competitive drive which is partly driven by his desire to stand out and excel in his career. This trait is amplified by the competitive atmosphere of his workplace and further amplified by his testosterone supplementation.

In 2016, a study similar to Trae's scenario was undertaken. In the experiment men were given exogenous testosterone and a task where they were to look at their own photos and say which photo looked most like them. They ended up picking the version that looked the most dominant looking face. Therefore it stands to reason that the added testosterone at a minimal makes you believe yourself to be more dominant. Therefore making you more confident and assertive which are traits of dominance.

[51]. Literature seems to support the notion of a feedback loop between testosterone and dominance[52]. Where testosterone increases the frequency of dominant behaviors [53], such as leadership and assertiveness[54], dominant behaviors increase the total amount of testosterone in an individual, feeding off of each other. In Trae's case, if he is assertive, views himself as more dominant, and makes decisions, then he may be more dominant. If he asserts himself in the face of a challenge and wins, this may cause his testosterone to rise[55], in a positive feedback loop. The biopsychosocial framework is an excellent tool for understanding the interplay of complicated systems. Although we have highlighted some significant factors affecting Trae's life in relation to testosterone and dominance, it is important that we investigate other confounding variables that may affect the interpretation of dominance and testosterone.

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In this chapter, we have investigated testosterone and dominance, respectively. We have used theoretical concepts in practical settings to understand the relationship between testosterone and dominance in respect to the biopsychosocial framework. The following section will investigate aggression as a confounding variable of dominance. As well as risk-taking as a dominance behavior.

Aggression

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Aggression is an extreme dominant behavior[56]. To understand why aggression is used as dominant behavior, we can look toward ethology. In animals, successful bouts of aggressive behaviors oftentimes lead to a reduction of challenge and an enhancement of resource control[57]. Such as, a pair of stags fighting for mating rights[grammar?]. In this case, more often than not, the most aggressive stag wins. While dominance and aggression can co-occur, it is essential to understand that the two are distinct from each other. Dominance is more focused on achieving control and social status, while aggression involves hostile or harmful actions aimed at others and may not always lead to higher social status[58]. Similarities between the two come in the form of access to resources, including food, water, power and mating privileges[59][60]. In this scenario, testosterone serves as the underlying driving force, consistently present and influencing severity; for instance, higher testosterone levels correspond with increased aggression and/or dominance[61]. Therefore, at the most basic level, aggression is an antecedent for control over resources. But why? Literature tells us that there is a clearcut causal link between aggression and testosterone [62]. Meaning, that there may be instances where aggression is mistaken for dominance or visa versa[grammar?]. Although aggression is the most effective form of dominance displays in animals[63], it isn't always the case in the complexity of modern day society. Moreover, there is one place where we can see an active link between aggression, testosterone and dominance.

In 1994 a large prison study measured basal testosterone levels in male inmates [64], revealing a link between aggression and testosterone. Individuals who had higher basal testosterone were noted to have a history of violent interpersonal crimes as oppose to milder crimes ( ie. theft, tax evasion etc.). Levels of basal testosterone were also observed to be predictors of non compliance with prison rules. The discussion section states that "High testosterone individuals are dominant and confrontational, and they showed up where they did not belong (often to engage in illicit activity according to prison staff). Those low in testosterone hold back, and they are notable more by their absence than their presence"[65]. The wording of their findings suggest that this study and possibly many other studies measuring aggression may be mistaking it for dominance and/or visa versa. This grey area is an avenue for further exploration.

In 2010, a study was done investigating aggression among zebrafish[66]. The study predominantly focused on gene expression and neurological expressions among fish. Interestingly enough, conclusions linked focused on aggression as a consequence of gene expression not hormonal fluctuations. Furthermore authors[grammar?], fail to make the distinction between 'aggression' and 'dominance', leaving the interpretation entirely up to the reader. Basal testosterone levels appear to be an accurate predictor for dominant behaviours such as aggression[67]. However, it should be considered that these study only reflect testosterone as a predictor for dominance rather than dominant behaviours.

Risk taking

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Throughout this chapter we have discussed several variables which are related to dominance and testosterone. one in particular stands out. Risk taking is any consciously or unconsciously controlled behavior with a perceived uncertainty about its outcome[68]. Examples of risky behaviours include, investing $200 into Bitcoin or engaging in unprotected sex. Although motivations for individuals undertaking "risky" behaviours vary, one commonality among risk takers is testosterone[69]. However, similar to how aggression isn't necessary to be dominant, higher testosterone does not mean greater risks. Ronay and von Hippal, predict that when primed with power, individuals tend to be more risk averse in the interest of maintaining power[70]. For example, if Trae holds the title of CEO, it would be in his best interest to avoid making decisions which put his position at risk. What is interesting, is that risk taking can be a successful predictor of dominance [71]. Meaning that risk taking can also be to some extent a predictor of testosterone in people[grammar?].

Traes[grammar?] Promotion

After Trae met with Billys[grammar?] supervisor Amiee, he was told that he would be given a much more important role within the organisation. He was told that the new role would come with many responsibilities and benefits including increased pay, higher level of recognition, more organizational power and a new pristine office. Trae is super excited for the role and will stop at nothing to maintain his position. He aims to avoid wasting resources and costing the firm any extra money to maintain his position.

This is an example of Ronay and von Hippals' power prediction.

In summary, the exploration of aggression and risk-taking reveals complex interconnections within testosterone and dominance. While aggression can be a manifestation of dominance, the distinction between the two is crucial, with testosterone playing a significant role in driving both behaviors. Additionally, risk-taking behavior, influenced by testosterone, provides another dimension to understanding dominance. Where higher testosterone levels do not always translate to greater risk-taking tendencies[grammar?]. However, in other contexts, risk-taking can indeed predict dominance, showcasing the intricate relationship between testosterone and dominance.This discussion holds importance as it sheds light on the nuanced nature of dominance, aggression, and risk-taking, emphasizing the need for a comprehensive understanding of these concepts. By delving into these connections, we gain valuable insights into the complexities of human behavior, bridging theoretical concepts with practical applications.

Criticisms

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Throughout the chapter we have explored various dominance related concepts such as aggression and risk taking. We have also and investigated the effects of testosterone as a driver of these constructs. However, it is important to understand that much of the existing literature is based on theory and that there are some elements that may have limitations. Meaning that it is important that we make considerations before jumping to absolute conclusions[grammar?].

Dominance narrative

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This criticism is about a narrative-based link between testosterone and dominance, which raises concerns about the internal validity of related research[72]. Internal validity refers to the extent to which a research study accurately measures or demonstrates what it intends to. For example, researchers may be looking to dominance to explain behavior when aggression may be the underlying factor. Alternatively, one study cites that dominance dispositions using self report measures of dominance have yielded inconsistent findings. The study suggests that alternatively, implicit power motivation is the factor that positively corresponds with baseline testosterone levels[73]. Meaning that implicit power motivation may be the construct being used interchangeably with dominance[grammar?]. Furthermore, a bias-prone, narrative-driven reviewing process could lead to confirmation bias, distorting research findings. . To enhance internal validity, researchers should employ standardized, reliable, and objective measures[74], such as hormonal assays and behavioral observations, to accurately capture the relationship between testosterone and dominance[75].

Inconsistent measures of testosterone

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Following the discussion on the external validity of dominance, it's essential to consider the internal reliability of testosterone findings. Internal reliability measures how consistently different items or questions produce similar results, ensuring that items within a scale or test are interrelated and measure the same underlying concept. In this chapter, we delved into distinctions between free and basal testosterone. However, literature on testosterone shows variation in measurement techniques. This discrepancy is problematic as free and basal testosterone measures cannot be used interchangeably[76], affecting the internal reliability of the research findings. Furthermore, in the diagnosis of TDS, only free testosterone is considered[77]. Meaning, that there may be difficulties when attempting to translate findings of basal testosterone studies in a clinical setting[grammar?]. It would be preferable if there was one universal measurement that could be used across all studies and practice.

Conclusion

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This exploration of the relationship between testosterone and dominance has shed light on the complex tapestry of human behavior. Through the lens of various theoretical frameworks and practical examples, we've deciphered the intricate relationships between hormones, behavior, and social dynamics.

Trae's journey exemplifies the profound impact of testosterone on biological, social, and psychological facets of human life. His physical transformation, marked by increased muscle mass and assertiveness[grammar?]. Provides a testament to the hormone's influence on body composition and behavior[grammar?]. Psychologically, Trae's heightened confidence, coupled with assertiveness and risk-taking tendencies, showcases the intricate interplay between hormones and mental states. Moreover, his social interactions, particularly in the workplace, reflect a positive feedback loop between dominance-related behaviors and social recognition, highlighting the role of social context in shaping dominance.

However, amid these insights, it's crucial to acknowledge the limitations and challenges within the existing literature. The dominance narrative, influenced by biases and narratives, and the inconsistent measures of testosterone pose significant hurdles in our pursuit of comprehensive understanding. Trae's case study, while illuminating, also emphasizes the complexity of applying theoretical knowledge to individual human experiences.

In navigating the complexities of dominance, aggression, and risk-taking, it's imperative to approach research with critical scrutiny. By acknowledging biases, considering diverse contexts, and embracing the evolving nature of scientific inquiry, we can refine our understanding of these intricate relationships. As we continue to explore the realms of hormones and behavior, Trae's story serves as a reminder of the rich complexity of human nature and the ongoing quest for a deeper comprehension of the forces that drive us.

See also

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Challenge hypothesis(Wikipedia)

Testosterone and violent crime (Book chapter, 2023)

Testosterone, winning, and losing (Book chapter, 2023)

References

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Basal testosterone, leadership and dominance: A field study and meta-analysis (Psychoeuroendocrinology)

The dominance behavioural system and psychopathology: evidence from self report, observational and biological studies (Psychological Bulletin)