Individual Differences In Testosterone Research Articles

A Bayesian Modeling Approach to Examine the Role of Testosterone Administration on the Endowment Effect and Risk-Taking

Financial risk-taking and loss aversion are multifaceted phenomena that are the focus of neuroscience, psychology, and economics research. A growing number of studies highlighted the role of hormones (particularly of testosterone) on socio-economic decision-making. However, the effects of testosterone on risk-taking under framing and consumer-based choices and preferences are inconclusive. We investigated the effects of 100 mg testosterone administration on aspects of decision-making within the Prospect Theory framework which is the most used descriptive model of decision-making under risk. We assessed risk-taking under framing and the endowment effect (effect of possession) using Bayesian modeling. Forty men participated in this double-blind placebo-controlled fully-randomized cross-over experiment and performed two tasks. One was a risk-taking task with binary choices under positive and negative framing associated with different probabilities. In the second task participants had to bid money for hedonic and utilitarian items. We observed a significant increase in serum testosterone concentrations after transdermal application. Compared to placebo, testosterone administration increased risk-taking under the positive framing (very large effect size) and decreased under the negative framing (moderate to small). The sensitivity to gain was positive in each framing. Our model showed that decision-making is jointly influenced by testosterone and the trade-off between gains and losses. However, while the endowment effect was more pronounced for hedonic than for utilitarian items, the effect was independent of testosterone. The findings provide novel information on the complex modulatory role of testosterone on risk-taking within the framework of prospect theory and shed light on mechanisms of behavioral economic biases. The proposed models of effects of individual differences in testosterone on risk-taking could be used as predictive models for reference-depended behavior under positive and negative framing with low and high probabilities.

Individual Differences in Testosterone and Self-Control Predict Compulsive Sexual Behavior Proneness in Young Males.

The ability to control sexual urges and impulses is essential to achieve individual and social harmony. Failing to regulate sexual behavior can lead to the interference with daily life goals, sexual diseases transmission and moral violations, among others. The dual control model of sexual response proposes that an imbalance between sexual excitation and sexual inhibition mechanisms may lead to sexual dysregulation, thereby explaining problematic sexual behavior. Interindividual differences in self-control and testosterone levels are likely to modulate sexual regulation mechanisms, but these individual features have scarcely been studied in the context of compulsive sexual behavior. This study investigated the role of sexual excitation and inhibition, self-control and testosterone levels in predicting individuals’ proneness to display compulsive sexual behavior. Seventy healthy young males provided a saliva sample for testosterone measurements and filled in questionnaires on self-control, sexual excitation, sexual inhibition, sexual compulsivity and sexual behavior. High testosterone levels and low self-control were associated with higher sexual compulsivity scores. Additionally, testosterone levels and sexual inhibition negatively predicted the frequency of sexual behavior with a partner. The results of our study highlight the joint role of psychological traits and testosterone levels in compulsive sexual behavior proneness, providing implications regarding the prevention and treatment of this condition in young males.

Facing off with the phalangeal phenomenon and editorial policies: A commentary on Swift-Gallant, Johnson, Di Rita and Breedlove (2020)

Swift-Gallant et al. (2020) provide a thought-provoking perspective on the topic of digit ratio research, research that has had some prominence in the journal Hormones and Behavior, and is research that has garnered much controversy. In this commentary on their paper, we add to the discussion of why there is skepticism of the use of digit ratios as a measure of individual differences in prenatal androgens, we comment on the mis-use of the facial width-to-height ratio as a measure of individual differences in testosterone, the grey areas in the interpretation of evidence, and we address the concern raised in their article regarding editorial policies at Hormones and Behavior (spoiler alert: there are no secret policies).

Neural substrates of male parochial altruism are modulated by testosterone and behavioral strategy

Parochial altruism refers to ingroup favoritism and outgroup hostility and has recently been linked to testosterone. Here, we investigated the neurobiological mechanism of parochial altruism in male soccer fans playing the ultimatum game (UG) against ingroup and outgroup members (i.e., fans of the favorite or of a rivalling team) using functional magnetic resonance imaging. Our results suggest that individual differences in altruistic tendency influence the tendency for parochialism. While altruistic subjects rejected unfair offers independent of team membership, the more self-oriented ‘pro-selfs’ displayed a stronger ingroup bias and rejected outgroup offers more often. However, during a second session that introduced a team competition the altruists adapted to this parochial pattern. Behavioral strategy was further characterized by dissociable and context-dependent correlations between endogenous testosterone and neural responses in the anterior insula and the ventromedial prefrontal cortex. In sum, the present findings indicate that parochial altruism is shaped by individual differences in testosterone and behavioral strategy. In that way the results are in line with evolutionary theories of both individual and group selection.

Physiology and pillow talk

This study investigates the association between individual differences in testosterone and communication after sexual activity. Two hundred and fifty-three young adult participants (78% women, M age = 21 years, 73% White) provided saliva samples (later assayed for testosterone) and subsequently, over a 2-week period, completed an online diary after each time they engaged in sexual activity. Individual differences in testosterone levels were inversely associated with perceived benefits of, and positively associated with perceived risks of, disclosing thoughts and feelings to one’s partner after sexual activity. When testosterone levels were higher, post sex disclosures were less intentional and less positive, and these associations were mediated by risk–benefit assessments. An interaction between testosterone and orgasm revealed that higher testosterone levels were associated with more negative post sex disclosures for those who did not orgasm, but not for those who experienced orgasm. This finding suggests that high testosterone/no orgasm individuals may be the least likely to experience the beneficial effects of post sex communication. Similar results were found both when biological sex was controlled for and when analyses were conducted separately for women and men. Implications for a biosocial model of post sex behavior and communication are discussed.

Natural variation in testosterone is associated with hypoalgesia in healthy women.

Sex differences in pain are well established, with women reporting greater incidence of clinical pain and heightened responsivity to experimental pain stimuli relative to men. Sex hormones (ie, estrogens, progestins, androgens) could contribute to extant differences in pain sensitivity between men and women. Despite this, there has been limited experimental research assessing the relationship between pain and sex hormones. The purpose of this study was to extend previous research and examine the association between sex hormones and nociceptive processing in healthy women. A total of 40 healthy women were tested during the mid-follicular, ovulatory, and late-luteal phases of the menstrual cycle (testing order counterbalanced). Salivary estradiol, progesterone, and testosterone were collected at each testing session and pain was examined from electrocutaneous threshold/tolerance, ischemia threshold/tolerance, and McGill Pain Questionnaire-Short Form ratings of noxious stimuli. Nociceptive flexion reflex threshold was assessed as a measure of spinal nociception. Overall, there were no significant menstrual phase-related differences in pain outcomes. Nonetheless, variability in testosterone (and to a lesser degree estradiol) was associated with pain; testosterone was antinociceptive, whereas estradiol was pronociceptive. No hormone was associated with nociceptive flexion reflex threshold. Although future research is needed to replicate and extend these findings to clinical populations (ie, chronic pain, premenstrual dysphoric disorder), results from the present study indicate that menstrual phase-related changes in sex hormones have minimal influence on experimental pain. However, individual differences in testosterone may play a protective role against pain in healthy women.

Testosterone responses to competition predict decreased trust ratings of emotionally neutral faces.

A wealth of evidence has linked individual differences in testosterone (T) to social, cognitive, and behavioral processes related to human dominance. Moreover, recent evidence indicates that a single administration of T reduces interpersonal trust in healthy young women. Here, in a sample of men and women (n=96), we investigated the extent to which endogenous fluctuations in T during a competitive interaction would predict subsequent ratings of trust from emotionally neutral faces. Results indicated that a rise in T predicted a decrease in trust ratings in men, but not women. These findings provide further support for the idea that competition-induced fluctuations in T may serve to modulate ongoing and/or future social behavior.

Genetic and environmental influences on testosterone in adolescents: Evidence for sex differences

The current study investigated genetic and environmental influences on salivary testosterone during adolescence, using data from 49 pairs of monozygotic twins and 68 pairs of dizygotic twins, ages 14-19 years (M = 16.0 years). Analyses tested for sex differences in genetic and environmental influences on testosterone and its relation to pubertal development. Among adolescent males, individual differences in testosterone were heritable (55%) and significantly associated with self-reported pubertal status (controlling for age) via common genetic influences. In contrast, there was minimal heritable variation in testosterone for females, and testosterone in females was not significantly associated with pubertal status after controlling for age. Rather, environmental influences shared by twins raised together accounted for nearly all of the familial similarity in female testosterone. This study adds to a small but growing body of research that investigates genetic influences on individual differences in behaviorally relevant hormones.

Genetic and environmental influences of daily and intra-individual variation in testosterone levels in middle-aged men

Testosterone regulates numerous physiological processes, and evidence suggests that it plays a critical role in male aging. It has yet to be determined whether the heritability of testosterone varies in accordance with its diurnal rhythm. Similarly, it is unclear whether changes in testosterone level throughout the day are genetically influenced. The aim of the present study was to determine the degree to which genetic and environmental factors contribute to individual differences in testosterone throughout the day in middle-aged men. Saliva-based measures of free testosterone, sampled at multiple time-points both at-home and in-lab, were collected from 783 male twins (193 monozygotic pairs, 196 dizygotic pairs, 5 unpaired twins) as part of the Vietnam Era Twin Study of Aging (VETSA). The average age of participants was 55.9 years (SD=2.6). Testosterone levels declined substantially over the course of the day, with 32-39% of the change occurring in the first 30min after waking. Heritability estimates for specific time-points ranged from .02 to .39. The heritability of the average at-home and in-lab testosterone values were notably higher (.42 and .47 respectively). Daily rates of change showed some evidence of genetic influence, with heritability estimates ranging from .15 to .29, whereas there were no observable genetic influences on coefficients of variation. Genetic influences account for a significant proportion of the variance in average testosterone levels, while environmental factors account for the majority of intra-individual variability. These results highlight the need to explore both genetic and individual-specific environmental factors as determinants of free testosterone levels in aging men.

Sociosexuality moderates the association between testosterone and relationship status in men and women

Single individuals typically have higher testosterone compared to those who are partnered, suggesting that individual differences in testosterone are associated with mating effort, or people's motivation to find a sexual partner. However, there is less consistent evidence for links between testosterone and sociosexuality, or people's orientation toward uncommitted sexual activity. Based on Penke and Asendorpf's (2008) conceptualization, we propose that a more nuanced measure of sociosexuality may reveal more robust associations with testosterone. In the current study, we assessed relations between three components of sociosexuality—desire, behavior, and attitudes—and endogenous testosterone levels in men and women. We found that partnered status was indeed associated with lower testosterone in both men and women, but only among those who reported more restricted sociosexuality. Partnered men who reported greater desire for uncommitted sexual activity had testosterone levels that were comparable to those of single men; partnered women who reported more frequent uncommitted sexual behavior had testosterone levels that were comparable to those of single women. These findings provide new evidence that people's orientations toward sexual relationships, in combination with their relationship status, are associated with individual differences in testosterone. The current results are also among the first to demonstrate sociosexuality–testosterone associations in both men and women, and they reveal that the nature of these associations varies by gender. Together, these findings highlight the utility of a multifaceted conceptualization of sociosexuality and the implications of this conceptualization for neuroendocrine processes.

Individual differences in testosterone and corticosterone levels in relation to early postnatal development in the rabbit Oryctolagus cuniculus

Many aspects of an animal's early development contribute to the emergence of individual differences in physiology. Here we asked whether litter size, birth mass, suckling success and postnatal growth were predictors of individual differences in testosterone (T) and corticosterone (CORT) levels in neonatal domestic rabbits. Serum concentrations of both hormones, which we measured on postnatal day 8, were significantly and positively correlated with pup growth and milk intake. Litter size and birth mass were not significantly correlated with levels of T and CORT, although both parameters were indirectly associated with the levels of these hormones via their effects on milk intake and pup growth. Our results highlight the importance of naturally occurring features of the postnatal environment in shaping individual differences in T and CORT levels during early life.

Reply to Joel and Tarrasch: On the relationship between testosterone, gender, financial risk aversion, and career choices

With regard to our recent paper on testosterone, financial risk aversion, and career choices in a large population of MBA students (1), there is nothing wrong in our data analyses, in our results, or in the conclusions we draw from them. Joel and Tarrasch (2) urge caution in drawing conclusions from correlational findings. We agree, and that is why, in the first sentence of the Discussion section of our paper, we stated that the results of our study suggest (rather than demonstrate) that testosterone has both organizational and activational effects on financial risk aversion and career choices. Joel and Tarrasch also maintain that the effects we report are not strong. We agree, and never claimed that they are. Given the nature of the question we addressed and the difficulty of conducting experimental hormonal manipulations in a human study with a large sample size such as ours, correlational data analyses are appropriate and can provide useful information. Moreover, given that interindividual variation in financial risk aversion and career choices is probably the result of multiple biological, social, and cultural factors, it would be surprising if the effects of testosterone were strong. Joel and Tarrasch argue that the correlation between testosterone and risk aversion or career choices may be the result of other variables that are independently correlated with both hormone concentrations and risk aversion or career choices. We acknowledged this possibility in our paper and examined some of these other variables. We are aware that behavior and environment can affect testosterone. We measured salivary testosterone concentrations before and after the subjects took the financial risk aversion test. We found that although the stress of taking the test reduced testosterone, especially in males, there was a significant positive correlation between the testosterone concentrations measured before and after the test, suggesting that individual differences in hormone concentrations were stable over time and regardless of the test. Variation in financial risk aversion and career choices was predicted by the average of the pretest and posttest testosterone concentrations, which likely reflects stable individual differences in testosterone and not the change in testosterone associated with the test. Joel and Tarrasch caution that it is wrong to assume that biological differences, such as between- or within-gender differences in testosterone concentrations, necessarily reflect innate factors. We agree, and in our paper we made no statements whatsoever regarding the origins of such differences. Stable individual differences in hormone concentrations are probably the result of multiple factors, including genetic predispositions, prenatal environmental influences, early postnatal experience, and current environment.

Testosterone, cognition, and social status

What leads some people to perform better than others on certain cognitive tasks? One explanation involves individual differences in testosterone. Testosterone is associated with higher performance on spatial tests, and lower performance on verbal tests. However, a large literature suggests that testosterone only predicts behavior when status is in jeopardy. In the present study, we manipulated status before administering a spatial and verbal test. In a high-status position, high-testosterone individuals performed well on both tests, and blood pressure dropped. In a low-status position, high-testosterone individuals performed relatively poorly on both tests, and blood pressure did not change. These data suggest that differences in cognitive performance stem from an interaction between testosterone and the social situation.

Salivary testosterone is related to both handedness and degree of linguistic lateralization in normal women

The aim of this study was to test the hypothesis that individual differences in testosterone (T) are associated with different patterns of linguistic lateralization and hand preference. Twenty left-handed (LH) and 19 right-handed (RH) women filled in a handedness questionnaire and performed a consonant–vowel dichotic listening test (DL-CV). Salivary T was measured by radioimmunoassay (RIA). LH women showed significantly lower mean salivary T than RH women. T levels were negatively correlated with the absolute value of the DL laterality index. Subjects with right ear advantage (REA) were classified into strongly and weakly lateralized following Wexler et al. method ( Brain Lang. 13 (1981) 13). When taking into account hand preference, a pattern emerged in that RH-strongly lateralized and LH-weakly lateralized women showed similar T levels. The lowest level appeared for LH-strongly lateralized women and the highest for RH-weakly lateralized women, being significantly different from each other. The results are discussed in terms of several theories that have proposed a link between testosterone and cerebral lateralization.

Testosterone and Occupational Achievement

Men with higher levels of serum testosterone have lower-status occupations, as indicated by archival data from 4,462 military veterans in six U.S. census occupational groups. This finding supports a structural equation model in which higher testosterone, mediated through lower intellectual ability, higher antisocial behavior, and lower education, leads away from white-collar occupations. The model is plausible because testosterone levels are heritable and available early enough to affect a number of paths leading to occupational achievement. Prior research has related testosterone to aggression in animals and men, and high levels of testosterone presumably evolved in association with dominance in individual and small-group settings. It appears an irony of androgens that testosterone, which evolved in support of a primitive kind of status, now conflicts with the achievement of occupational status. Occupations are cultural creations, and cultural forces lead us toward or away from them. The choice of an occupation depends upon skill, experience, and the work available in a particular society. Biological factors are not usually considered, beyond those so potent as to be of little psychological interest: sumo wrestlers are large, airline pilots have good vision, and most professors are mentally competent. But on a subtle level, biological factors act through small and continuing effects on thoughts, feelings, and behavior. Arvey et al. (1989) found job satisfaction to be heritable, though they did not indicate the biological factors that are important or the pathways through which these factors operate. The hormone testosterone may be one such factor. Testosterone has been associated with dominance (Mazur 1985), aggression (Bernstein, Rose & Gordon 1974; Rose 1978), antisocial behavior (Dabbs & Morris 1990), sensation seeking (Daitzman & Zuckerman 1980), automaticity and perseverant responding (Broverman et al. 1964; van Hest, van Haaren & van de Poll 1989), libido (Morris et al. 1987; Sherwin, Gelfand & Brender 1985), low verbal intelligence * This work was supported bygrantMH42525from theAntisocial and ViolentBehaviorBranch of the National Institute of Mental Health. Data were originally gathered as part of the Vietnam Experience Study, conducted by the Centers for Disease Control, U. S. Public Health Service, under a cooperative agreement with the Veterans Administration. I thank Julie Chambliss for her extensive and careful help in correcting the occupational codes. Direct correspondence to James M. Dabbs, Jr., Department of Psychology, Georgia State University, Atlanta, GA 30303. i The University of North Carolina Press Social Forces, March 1992, 70(3):813-824 This content downloaded from 157.55.39.184 on Sun, 15 May 2016 05:29:01 UTC All use subject to http://about.jstor.org/terms 814 / Social Forces 70:3, March 1992 (Dabbs, Jurkovic & Frady 1991), and lower verbal than spatial intelligence (Christiansen & Knussmann 1987). Testosterone in utero leads to sexual differentiation and development of the right side of the brain, possibly related to increased spatial ability and decreased verbal ability (Geschwind & Behan 1984). Receptors in the amygdala, hypothalamus, and preoptic areas (Rees, Bonsall & Michael 1986) could allow testosterone to affect on-going functioning of the brain. Three studies have related testosterone to occupation. Schindler (1979), studying 64 women, found salivary testosterone higher in attorneys than in athletes, nurses, or teachers. Purifoy and Koopmans (1979), studying 55 women, found serum testosterone higher in women who were students or professional and technical workers than in those who were clerical workers or housewives. Dabbs, de La Rue & Williams (1990), studying 67 actors, ministers, professors, physicians, firemen, salesmen, and football players, found salivary testosterone higher among actors and football players than among ministers; they replicated the actor-minister difference among 48 subjects in two additional studies. Individual differences in testosterone are heritable (Meikle et al. 1987) and thus could enter into causal chains leading to occupational choice. Because testosterone is an archaic hormone, present in many animals and even plants, there is no reason to expect it to be closely related to modem human occupations. However, behavioral and cognitive correlates of testosterone might make a person better suited to one occupation or another. In particular, antisocial and violent tendencies (Dabbs & Morris 1990) could lead to behavior and educational levels that are more appropriate for some occupations than others. The occupational studies have involved small samples and a limited range of occupations. More information is needed, including information on mediating variables. The present study examined testosterone, antisocial behavior, education, intelligence, and occupation in a large sample of former military servicemen. Structural equation models tested the hypothesis that a relationship between testosterone and occupational choice is mediated by antisocial behavior, intellectual ability, and education.

Salivary Testosterone Measurements among Women: Relative Magnitude of Circadian and Menstrual Cycles

Measures of testosterone among women are potentially useful in behavioral research, but information is needed on how much error is introduced by variability across the menstrual cycle. Morning and evening salivary testosterone concentrations were measured at weekly intervals across one menstrual cycle in each of 22 women, using the luteinizing hormone surge to mark midcycle. Menstrual cycles were statistically significant but smaller than daily cycles or individual differences. Menstrual cycle effects can be ignored in most research relating psychological and behavioral variables to individual differences in testosterone.