The effects of money exposure on testosterone and

Personality and Individual Differences 123 (2018) 110–114

Contents lists available at ScienceDirect

Personality and Individual Differences journal homepage: www.elsevier.com/locate/paid

The effects of money exposure on testosterone and risk-taking, and the moderating role of narcissism☆

T

⁎

Eric P. Stenstroma, , John B. Dinsmoreb, Jonathan W. Kunstmana, Kathleen D. Vohsc a

Miami University, USA Wright State University, USA c University of Minnesota, USA b

A R T I C L E I N F O

A B S T R A C T

Keywords: Money Testosterone Narcissism Risk-taking

Although prior research has demonstrated that reminders of money influence motivations and behaviors, there has been scant attention to whether money cues can alter physiological responses. An experiment testing male participants assessed whether being randomly assigned to handle money versus paper would change men's testosterone levels and affect financial risk-taking. Results showed that the effects of handling money on testosterone levels and risk-taking depended on trait narcissism. Among men low in narcissism, handling money led to a greater increase in testosterone levels from Time 1 (baseline) to Time 2 (post-manipulation) compared with their counterparts in a neutral, non-money condition. Conversely, highly narcissistic men who were randomly assigned to handle money exhibited a weaker increase in testosterone levels relative to men in the neutral condition. The results of moderated mediation analyses suggested that money exposure affected financial risktaking through changes in testosterone levels. Men low in narcissism became more inclined to take risks through an increase in testosterone levels, whereas men high in narcissism became more risk averse via a decrease in testosterone levels.

1. Introduction Prior research has established that reminders of money can affect motivation, thought, and behavior (Vohs, 2015). For instance, thoughts of money decrease prosocial behavior (Gasiorowska, Chaplin, Zaleskiewicz, Wygrab, & Vohs, 2016; Vohs, Mead, & Goode, 2006) and increase task performance (Boucher & Kofos, 2012; Gasiorowska et al., 2016). Handling money renders people relatively impervious to social exclusion and physical pain (Zhou, Vohs, & Baumeister, 2009). The current work sought to test potential physiological changes associated with being reminded of money in order to potentially help account for behavioral findings. Via random assignment to condition, some participants handled a large amount of money, whereas others handled slips of paper. Our main goal was to assess the effects of handling money on changes in testosterone levels and a decision making correlate of testosterone, risk-taking. According to the Tool Theory of money motivation, money's psychological effects derive from its utility to achieve goals such as status ascension (Kniffin, 2006; Lea & Webley, 2006). Drawing from Tool Theory, we posit that handling money will elicit an increase in

testosterone levels, a hormone that has long been associated with status (Archer, 2006; Geniole, Bird, Ruddick, & Carré, 2017; Mazur & Booth, 1998; Zilioli & Bird, 2017). Testosterone levels have been shown to rise after engaging in conspicuous consumption (Saad & Vongas, 2009) and after winning (versus losing) in a variety of competitions including athletics (Booth, Shelley, Mazur, Tharp, & Kittok, 1989), video games (Carré, Campbell, Lozoya, Goetz, & Welker, 2013; Zilioli & Watson, 2012), and games of chance (Apicella, Dreber, & Mollerstrom, 2014; McCaul, Gladue, & Joppa, 1992; see Zilioli & Bird, 2017, for a review). Given that money can serve as a means of achieving status, and that testosterone levels are positively associated with social status, we expect handling money will result in a rise in testosterone levels. Testosterone's links to status dovetail with an individual difference in the desire for status, trait narcissism, which we measured as a way to assess the status implications of handling money. Narcissism is characterized by the motivation to self-enhance and gain recognition and admiration by identifying and optimizing self-presentation events in one's social environment (Pincus et al., 2009). In response to an aggression solicitation paradigm, narcissism predicts a greater rise in testosterone levels and more aggressive behavior in the form of white

☆ This research was supported by a Rike Consumer Research Foundation Research Grant from Wright State University. The first author acknowledges the support he received from his Richard T. Farmer Endowed Assistant Professorship and research grants from the Farmer School of Business, the Department of Marketing, and Miami University. ⁎ Corresponding author at: Farmer School of Business, Miami University, 800 E. High St, Oxford, Ohio 45056, USA. E-mail address: [email protected] (E.P. Stenstrom).

https://doi.org/10.1016/j.paid.2017.10.035 Received 12 July 2017; Received in revised form 25 October 2017; Accepted 26 October 2017 Available online 15 November 2017 0191-8869/ © 2017 Elsevier Ltd. All rights reserved.


E.P. Stenstrom et al.

2. Method

noise blasts directed at an ostensible opponent of a reaction-time game (Lobbestael, Baumeister, Fiebig, & Eckel, 2014). The literature seems to point to two ways in which narcissism might impact how testosterone levels change in response to handling money. On one hand, some research suggests that handling money could lead to a greater testosterone increase among narcissists compared to nonnarcissistic people. Narcissists are focused on their social rank and seek opportunities to improve their rank through enhanced self-presentation (Marshall, Lefringhausen, & Ferenczi, 2015; Sorokowski et al., 2015; Weiser, 2015) and devaluing others (Krizan & Bushman, 2011; Pincus et al., 2009). In romantic relationships, narcissists are more likely to pursue short-term mating strategies (Schmitt et al., 2017), to seek admiration rather than intimacy, and to target romantic partners whose beauty or social rank can enhance their status (Campbell, 1999). Considering that narcissists are highly motivated by status concerns, one might expect that handling large amounts of money will lead to a greater increase in status and testosterone levels among highly narcissistic men relative to those low in narcissism. On the other hand, some literature suggests that handling money could result in a decrease in testosterone levels among highly narcissistic men. Narcissists have a grandiose self-concept (Morf & Rhodewalt, 2001) and tend to be overconfident (Campbell, Goodie, & Foster, 2004). However, their grandiose ego is coupled with a highly vulnerable and fragile self-concept, producing a constant search for external affirmation (Morf & Rhodewalt, 2001). Narcissists' quest for status and admiration leads to a tendency to make frequent social comparisons (Krizan & Bushman, 2011). Compared to those low in narcissism, highly narcissistic people respond negatively to upward social comparisons (Bogart, Benotsch, & Pavlovic, 2004; Nicholls & Stukas, 2011). Narcissists who were instructed to handle large amounts of money might be inclined to mentally simulate what it would be like to possess that money and compare it to their current access to money or wealth. This comparison may act like a threat and engender a decrease in testosterone levels. Given this mixed literature, we took an exploratory approach and remained agnostic towards how narcissism might influence the effect of money on testosterone levels. We assessed a form of decision making associated with status, narcissism, and testosterone, namely risk-taking. Narcissism has been shown to be predictive of greater risk-taking (Campbell et al., 2004) and gambling behavior (Lakey, Rose, Campbell, & Goodie, 2008). There is also considerable evidence suggesting that testosterone levels are positively associated with risk-taking. Although some research has found no association between testosterone and risk-taking (Derntl, Pintzinger, Kryspin-Exner, & Schöpf, 2014; Zethraeus et al., 2009) or a non-linear association between these two factors (Stanton, MulletteGillman, et al., 2011), many studies have revealed a positive relationship between risk-taking and various indicators of testosterone, from prenatal to circulating (Apicella et al., 2008; Apicella et al., 2014; Stanton, Liening, & Schultheiss, 2011; Stenstrom, Saad, Nepomuceno, & Mendenhall, 2011; van Honk et al., 2004). Based on this literature, we expected that testosterone changes elicited by money exposure would likely be positively associated with risk-taking. An experiment tested how handling money, versus slips of paper (as a non-money cue), impacts testosterone levels and subsequent risktaking, potentially as a function of trait narcissism. We assessed testosterone levels before and after a money exposure manipulation. Testosterone levels in men are generally more responsive to situational factors than are women's (Mazur & Booth, 1998; see Geniole et al., 2017, for a meta-analysis), and therefore we tested only men. Money exposure was manipulated by having participants either handle $1600, a large amount of currency (money condition), or bill-sized slips of paper (neutral condition; Supplement S1).

2.1. Participants and procedure One hundred and nine men participated in exchange for a $15 Amazon gift card and a chance to win additional money via a decision making task. We followed standard salivary testosterone collection procedures (as recommended by Schultheiss & Stanton, 2009, Zilioli & Watson, 2014, Blascovich, Vanman, Mendes, & Dickerson, 2011, and the Salimetrics lab that analyzed our saliva samples). After excluding two participants for reporting an oral disease (Zilioli & Watson, 2014), two for an insufficient amount of saliva which prevented testosterone assaying, and one for not correctly completing the risk-taking task (who selected not one but both of the options, rendering it impossible to calculate a total score), the final sample consisted of 104 participants (Mage = 20.63, SDage = 2.39). Data collection took place twice, at the end of the spring and fall 2015 semesters. During the fall session we added a third condition wherein participants handled small amounts of money (40 $1 bills), which falls outside of the scope of the current manuscript and is reported in the Supplementary Materials (the procedure and results are reported in Supplements S2 and S3, respectively). It should be noted that we had intended to report the two data collections as two experiments. Given that they used the same procedures and tasks, we opted to report them as one study in order to conduct higher powered analyses and gain more accurate estimates (Cumming, 2013). Participants were instructed to refrain from eating, drinking (except for water), or using nicotine for one hour prior to the scheduled start of the experiment (Zilioli & Watson, 2014). Sessions were conducted between 11:50 am and 5:30 pm. Upon arrival, participants were asked by the experimenter when they had last eaten, drank, and consumed nicotine in order to confirm that they had followed the fasting instructions. Next, students were asked to watch 10 min of relaxing nature videos to induce a calm state. Participants were then instructed by the experimenter to rinse their mouths with water three times before watching another 10 min of calming videos. They were subsequently asked to passively drool approximately 1.0 ml of saliva into a polypropylene vial using a Salimetrics saliva collection aid to measure premanipulation testosterone levels. Saliva samples were immediately stored in a freezer at − 20 °C. Following the saliva sampling, participants were randomly assigned to a money condition (a sorting task with 80 $20 bills) or a neutral condition (sorting 80 plain pieces of paper with the same size dimensions as $20 bills; Zhou et al., 2009; Supplement S1) in a betweensubjects design (see Supplement S4 for sorting task details). Participants subsequently completed a financial risk-taking task with real monetary outcomes (Holt & Laury, 2002; Supplement S5). They were presented with 10 lotteries, each with a safer option and a riskier option. The number of risky options chosen was our measure of risk-taking (0 to 10). Fifteen minutes after the sorting task, a second saliva sample was taken (Mehta & Josephs, 2006). We then measured narcissism using a reduced 28-item version of the Pathological Narcissism Inventory (Pincus et al., 2009; Supplement S6). Responses were given on a 5-point scale (1 = strongly disagree, 5 = strongly agree) and scores were averaged (α = 0.89). Next, we measured the number of alcoholic drinks consumed within the last 12 h, the number of caffeinated beverages consumed that day, how much time they exercised that day, and the number of nicotine products used that day (van Anders & Goldey, 2010; Zilioli & Watson, 2014). We also collected basic demographic information. Last, participants were given their earnings from the risktaking task. Saliva samples were packaged with dry ice and shipped overnight to Salimetrics (Carlsbad, CA) for analysis. There, each sample was assayed, in duplicate, using a sensitive enzyme immunoassay for 111



change, β = − 35.48, t = 3.66, p < 0.001, 95% CI [−54.70, − 16.26]). Among low narcissism participants (−1 SD; PNI = 2.44), being assigned to the money condition produced a larger testosterone increase from Time 1 to Time 2 compared with being assigned to the neutral condition (Mmoney = 13.16, Mneutral = − 3.32), β = 16.48, t = 2.19, p = 0.031, 95% CI [1.54, 31.42]. For more narcissistic participants (+1 SD; PNI = 3.54), being assigned to the money condition led to a weaker increase in testosterone levels compared to being assigned to the neutral condition (Mmoney = 2.76, Mneutral = 25.34), β = −22.59, t = 3.01, p = 0.003, 95% CI [−37.50, −7.68]. Within the neutral condition, there was a significant positive association between narcissism scores and testosterone change, β = 26.03, t = 3.84, p < 0.001, 95% CI [12.39, 39.67], R2 = 0.23. There was no significant association between narcissism scores and testosterone change within the money condition, β = − 9.45, t = 1.37, p = 0.177, 95% CI [−23.30, 4.39].

Table 1 Descriptive statistics.

Testosterone Time 1 (pg/ml) Testosterone Time 2 (pg/ml) Testosterone change (pg/ml) Narcissism (PNI) Risk-taking

Both conditions (N = 104)

Neutral condition (n = 51)

Money condition (n = 53)

M

SD

M

SD

M

SD

176.08

65.31

177.86

60.83

174.36

69.89

185.95

70.13

189.50

65.24

182.54

75.00

9.88

28.74

11.64

29.81

8.18

27.84

2.99 5.08

0.55 1.98

3.01 5.57

0.55 1.71

2.97 4.60

0.56 2.12

testosterone. The average intra-assay coefficients of variation was 7.34% and the inter-assay coefficients of variation averaged across low and high controls was 5.48%.

3.3. Risk preferences We tested whether testosterone change, money condition, trait narcissism, or the interaction of condition and trait narcissism predicted risk scores using the PROCESS macro for model 8 (Hayes, 2013; N = 104). There was not a significant effect of testosterone change on risk preferences, although it's worth noting that there was a positive trend, β = 0.01, t = 1.75, p = 0.083, 95% CI [0.00, 0.03], and that a significant direct effect of the mediator on the dependent variable is not required to establish mediation (Zhao, Lynch, & Chen, 2010, p. 204). There was not a significant association between narcissism scores and risk preferences, β = − 0.23, t = 0.65, p = 0.514, 95% CI [−0.92, 0.46], nor was there a significant interaction between condition and narcissism, β = 1.30, t = 1.78, p = 0.077, 95% CI [− 0.14, 2.75]. There was a significant main effect of condition on risk scores, such that those in the money condition were more risk aversive than those in the neutral condition, β = − 0.93, t = 2.48, p = 0.015, 95% CI [−1.68, − 0.19], R2 = 0.06.

3. Results 3.1. Manipulation check Total sorting time did not differ significantly between conditions (nneutral = 51; Mneutral = 356.04 s, SDneutral = 83.60; nmoney = 53; Mmoney = 370.42, SDmoney = 73.48), t = 0.93, p = 0.353, 95% CI [−44.96, 16.21]. The equivalency across conditions suggests that any differences in outcomes were not a function of task difficulty. 3.2. Testosterone change Mean Time 1 (baseline) and Time 2 (post-manipulation) testosterone levels were 176.08 pg/ml (SD = 65.31) and 185.95 pg/ml (SD = 70.13), respectively (see Table 1 for descriptive statistics). Time 1 testosterone levels were not significantly associated with narcissism scores, r = 0.048, p = 0.734 (see Table 2 for intercorrelations among variables). There were no significant differences in Time 1 testosterone levels as a function of experimental condition, t = 0.27, p = 0.786, 95% CI [− 22.03, 29.02]. Likewise, narcissism scores did not significantly differ between conditions, t = 0.44, p = 0.664, 95% CI [−0.17, 0.26]. Testosterone change was calculated using standard practices, by subtracting each participant's Time 1 testosterone level from their Time 2 level (Apicella et al., 2014; Zilioli & Watson, 2014). We tested if trait narcissism moderated an effect of money condition on testosterone change using the PROCESS macro for model 1 (Hayes, 2013; version 2.15; continuous predictors were mean centered prior to all regression analyses; N = 104). There was not a significant effect of condition on testosterone change, β = − 3.05, t = 0.58, p = 0.566, 95% CI [− 13.58, 7.47]), nor was there a significant association between narcissism scores and testosterone change, β = 7.95, t = 1.64, p = 0.104, 95% CI [−1.66, 17.55]. However, there was a significant interaction between condition and narcissism scores on testosterone

3.4. Moderated mediation Prior to testing for moderated mediation, we tested two simple mediation models (an indirect effect of money on risk preferences through testosterone changes, and an indirect effect of narcissism on risk scores via testosterone changes), neither of which yielded a significant indirect effect (Supplement S7). We subsequently tested a moderated mediation model in which trait narcissism (Mod) moderated the effect of money condition (X) on testosterone change (Med), and in which this interaction helped predict risk-taking scores (Y). The PROCESS macro for model 8 (Hayes, 2013; Krishna, 2016; N = 104) showed a significant moderated mediation pattern (index of moderated mediation = − 0.44, SE = 0.23, 95% CI [− 0.95, − 0.09]). Among low-narcissism participants (− 1 SD; PNI = 2.44), being in the money, versus neutral, condition evinced a significant positive effect on risk-taking through an increase in testosterone levels (conditional indirect effect = 0.20, SE = 0.13, 95% CI [0.02, 0.54]). That is, for participants low in narcissism, their increased risk-taking from being assigned to the money, versus neutral, condition was partly explained by a rise in testosterone levels. Among highly narcissistic participants (+ 1 SD; PNI = 3.54), being in the money, compared to the neutral condition, revealed a significant, negative effect on risk-taking through a decrease in testosterone levels (conditional indirect effect = − 0.28, SE = 0.16, 95% CI: −0.84, − 0.06). That is, among participants high in narcissism, a drop in testosterone levels helped to explain a pattern of greater risk aversion among participants in the money, compared to neutral, condition.

Table 2 Intercorrelations among variables. Variable

1

2

3

4

5

1. 2. 3. 4. 5.

1 0.912⁎ − 0.046 − 0.146 0.138

1 0.367⁎ −0.074 0.179

1 0.152 0.123

1 −0.024

1

⁎

Testosterone Time 1 (pg/ml) Testosterone Time 2 (pg/ml) Testosterone change (pg/ml) Narcissism (PNI) Risk-taking p < 0.001.

112



4. Discussion

potential future research direction might be to explore how other hormones might respond to money primes and/or interact with testosterone responses to impact risk preferences. For instance, given the studies showing that cortisol interacts with testosterone to predict risktaking (Danese, Fernandes, Watson, & Zilioli, 2017), future research examining testosterone responses to status cues might benefit from also measuring cortisol. Our findings add to the growing bodies of work investigating the role of money cues (Tong, Zheng, & Zhao, 2013), narcissism (Hyun, Park, & Park, 2016), and physiology in influencing consumer behavior (Giddens, Schermer, & Vernon, 2009; Nepomuceno, Saad, Stenstrom, Mendenhall, & Iglesias, 2016; Röder, Brewer, & Fink, 2009). Although our research showed that money exposure results in a rise in testosterone levels and subsequent financial risk-taking among men low in narcissism, it is unclear if these effects have downstream personal or social implications. Given that testosterone levels are positively associated with status motives (Archer, 2006; Zilioli & Bird, 2017), reminders of money may motivate non-narcissistic men to strive for status by signaling their competence and generosity to others (Anderson & Kilduff, 2009) or by engaging in conspicuous consumption (Sundie et al., 2011). Furthermore, considering the evidence linking testosterone to aggression (Carré & Archer, 2018), an increase in testosterone levels in response to money exposure might also lead to aggression or to other nefarious behavior such as cheating, lying, or sabotaging rivals in pursuit of rank ascension. Accordingly, future research could explore if money exposure among non-narcissists promotes prosocial or antisocial behavior geared at gaining status.

The findings of an experiment suggest that exposure to money elicits changes in testosterone levels and risk-taking in men, and that the direction of these effects depends on trait narcissism. Among men low in narcissism, handling money resulted in a greater increase in testosterone levels compared with handling paper. To our knowledge, this testosterone increase is the first direct evidence of a physiological response to money exposure. Furthermore, considering the established association between testosterone and status (Mazur & Booth, 1998), our finding that handling money elicited a rise in testosterone levels among non-narcissists may lend support to the Tool Theory of money motivation, which posits that responses to money are derived from evolved instincts such as status seeking (Kniffin, 2006; Lea & Webley, 2006). Testosterone and risk-taking responses to status-related cues may have been selected for by promoting fitness in ancestral environments. For more narcissistic men, handling money surprisingly led to a significantly weaker increase in testosterone levels relative to handling paper. Since narcissists have a vulnerable and fragile self-concept (Morf & Rhodewalt, 2001), frequently make social comparisons (Krizan & Bushman, 2011), and respond negatively to upward comparisons (Bogart et al., 2004; Nicholls & Stukas, 2011), handling large amounts of money might have led to aversive upward status-related comparisons. To the extent that this may have occurred, a weak testosterone response to handling large amounts of money may have been the result. Moreover, the moderated mediation results suggest the effects of money exposure on testosterone levels have downstream effects on decision making. Handling money, relative to handling paper, led to heightened risk-taking through increased testosterone levels among men low in narcissism. Considering the positive relationship between testosterone and status motives (Archer, 2006; Zilioli & Bird, 2017), the rise in testosterone levels in response to handling money among nonnarcissistic men might have motivated them to take financial risks in hopes of gaining status through monetary rewards. In contrast, among more narcissistic men, handling money resulted in less risk-taking via reduced testosterone levels. While these findings are in line with research showing a positive relationship between testosterone changes and risk preferences (Apicella et al., 2014), they are the first to suggest that money exposure can lead to shifts in risk-taking. Future research could investigate if some of the established effects of money reminders on motives, thoughts, and behavior might also be mediated by testosterone changes. For instance, given the research linking testosterone to status motives (Archer, 2006; Zilioli & Bird, 2017), and that performance may serve as a means of gaining status, researchers could test if the effects of money cues on task persistence and performance (e.g., Gasiorowska et al., 2016) could be partly explained by shifts in testosterone levels. Limitations of the current work suggest additional avenues for future research. Chief among these are the unexpectedly strong increase in testosterone levels among more narcissistic men after handling slips of paper. We find this difficult to understand, but perhaps features of the experiment, from the vaguely competitive nature of the sorting task to the inclusion of a lottery in the risk-taking task, may have unintentionally put them into a competitive mindset or led them to envision winning, both of which have been shown to increase testosterone levels (Archer, 2006; Zilioli & Bird, 2017). Another note is that all the experimenters in the current work were young women. Cross-sex interactions can increase testosterone levels (e.g., van der Meij, Buunk, van de Sande, & Salvador, 2008). However, once again, why these processes would occur only with more narcissistic men who frankly performed a fairly natural task, we are not certain. Future studies may investigate how features of the experiment might influence the effects of money on testosterone levels among narcissistic men. Additionally, future research on whether money exposure elicits upward wealth comparisons could help explain why narcissists responded to handling money with a weaker testosterone increase compared to handling paper. Another

Appendix A. Supplementary data Supplementary data to this article can be found online at https:// doi.org/10.1016/j.paid.2017.10.035. References van Anders, S. M., & Goldey, K. L. (2010). Testosterone and partnering are linked via relationship status for women and ‘relationship orientation’ for men. Hormones and Behavior, 58(5), 820–826. Anderson, C., & Kilduff, G. J. (2009). The pursuit of status in social groups. Current Directions in Psychological Science, 18(5), 295–298. Apicella, C. L., Dreber, A., Campbell, B., Gray, P. B., Hoffman, M., & Little, A. C. (2008). Testosterone and financial risk preferences. Evolution and Human Behavior, 29(6), 384–390. Apicella, C. L., Dreber, A., & Mollerstrom, J. (2014). Salivary testosterone change following monetary wins and losses predicts future financial risk-taking. Psychoneuroendocrinology, 39, 58–64. Archer, J. (2006). Testosterone and human aggression: An evaluation of the challenge hypothesis. Neuroscience & Biobehavioral Reviews, 30(3), 319–345. Blascovich, J., Vanman, E., Mendes, W. B., & Dickerson, S. (2011). Social psychophysiology for social and personality psychology. Thousand Oaks, California: Sage Publications. Bogart, L. M., Benotsch, E. G., & Pavlovic, J. D. P. (2004). Feeling superior but threatened: The relation of narcissism to social comparison. Basic and Applied Social Psychology, 26(1), 35–44. Booth, A., Shelley, G., Mazur, A., Tharp, G., & Kittok, R. (1989). Testosterone, and winning and losing in human competition. Hormones and Behavior, 23(4), 556–571. Boucher, H. C., & Kofos, M. N. (2012). The idea of money counteracts ego depletion effects. Journal of Experimental Social Psychology, 48(4), 804–810. Campbell, W. K. (1999). Narcissism and romantic attraction. Journal of Personality and Social Psychology, 77(6), 1254. Campbell, W. K., Goodie, A. S., & Foster, J. D. (2004). Narcissism, confidence, and risk attitude. Journal of Behavioral Decision Making, 17(4), 297–311. Carré, J. M., & Archer, J. (2018). Testosterone and human behavior: The role of individual and contextual variables. Current Opinion in Psychology, 19(1), 149–153. Carré, J. M., Campbell, J. A., Lozoya, E., Goetz, S. M., & Welker, K. M. (2013). Changes in testosterone mediate the effect of winning on subsequent aggressive behaviour. Psychoneuroendocrinology, 38(10), 2034–2041. Cumming, G. (2013). The new statistics why and how. Psychological Science, 25(1), 7–29. Danese, G., Fernandes, E., Watson, N. V., & Zilioli, S. (2017). Testosterone and cortisol jointly predict the ambiguity premium in an Ellsberg-urns experiment. Frontiers in Behavioral Neuroscience, 11, 1–9. Derntl, B., Pintzinger, N., Kryspin-Exner, I., & Schöpf, V. (2014). The impact of sex hormone concentrations on decision-making in females and males. Frontiers in Neuroscience, 8, 1–11. Gasiorowska, A., Chaplin, L. N., Zaleskiewicz, T., Wygrab, S., & Vohs, K. D. (2016). Money cues increase agency and decrease prosociality among children: Early signs of

113



Röder, S., Brewer, G., & Fink, B. (2009). Menstrual cycle shifts in women's self-perception and motivation: A daily report method. Personality and Individual Differences, 47(6), 616–619. Saad, G., & Vongas, J. G. (2009). The effect of conspicuous consumption on men's testosterone levels. Organizational Behavior and Human Decision Processes, 110(2), 80–92. Schmitt, D. P., Alcalay, L., Alves, I. C. B., Anderson, C. A., Angelini, A. L., Asendorpf, J. B., ... Zupančič, A. (2017). Narcissism and the strategic pursuit of short-term mating: Universal links across 11 world regions of the international sexuality description project-2. Psychological Topics, 26(1), 89–137. Schultheiss, O. C., & Stanton, S. J. (2009). Assessment of salivary hormones. In E. Harmon-Jones, & J. S. Beer (Eds.). Methods in social neuroscience (pp. 17–44). New York, NY: The Guilford Press. Sorokowski, P., Sorokowska, A., Oleszkiewicz, A., Frackowiak, T., Huk, A., & Pisanski, K. (2015). Selfie posting behaviors are associated with narcissism among men. Personality and Individual Differences, 85, 123–127. Stanton, S. J., Liening, S. H., & Schultheiss, O. C. (2011). Testosterone is positively associated with risk taking in the Iowa gambling task. Hormones and Behavior, 59(2), 252–256. Stanton, S. J., Mullette-Gillman, O. D. A., McLaurin, R. E., Kuhn, C. M., LaBar, K. S., Platt, M. L., & Huettel, S. A. (2011). Low-and high-testosterone individuals exhibit decreased aversion to economic risk. Psychological Science, 22(4), 447–453. Stenstrom, E., Saad, G., Nepomuceno, M. V., & Mendenhall, Z. (2011). Testosterone and domain-specific risk: Digit ratios (2D: 4D and rel2) as predictors of recreational, financial, and social risk-taking behaviors. Personality and Individual Differences, 51(4), 412–416. Sundie, J. M., Kenrick, D. T., Griskevicius, V., Tybur, J. M., Vohs, K. D., & Beal, D. J. (2011). Peacocks, Porsches, and Thorstein Veblen: Conspicuous consumption as a sexual signaling system. Journal of Personality and Social Psychology, 100(4), 664. Tong, L., Zheng, Y., & Zhao, P. (2013). Is money really the root of all evil? The impact of priming money on consumer choice. Marketing Letters, 24(2), 119–129. Vohs, K. D. (2015). Money priming can change people's thoughts, feelings, motivations, and behaviors: An update on 10 years of experiments. Journal of Experimental Psychology: General, 144(4), e86. Vohs, K. D., Mead, N. L., & Goode, M. R. (2006). The psychological consequences of money. Science, 314(5802), 1154–1156. Weiser, E. B. (2015). # Me: Narcissism and its facets as predictors of selfie-posting frequency. Personality and Individual Differences, 86, 477–481. Zethraeus, N., Kocoska-Maras, L., Ellingsen, T., Von Schoultz, B. O., Hirschberg, A. L., & Johannesson, M. (2009). A randomized trial of the effect of estrogen and testosterone on economic behavior. Proceedings of the National Academy of Sciences, 106(16), 6535–6538. Zhao, X., Lynch, J. G., & Chen, Q. (2010). Reconsidering Baron and Kenny: Myths and truths about mediation analysis. Journal of Consumer Research, 37(2), 197–206. Zhou, X., Vohs, K. D., & Baumeister, R. F. (2009). The symbolic power of money reminders of money alter social distress and physical pain. Psychological Science, 20(6), 700–706. Zilioli, S., & Bird, B. M. (2017). Functional significance of men's testosterone reactivity to social stimuli. Frontiers in Neuroendocrinology, 47, 1–18. Zilioli, S., & Watson, N. V. (2012). The hidden dimensions of the competition effect: Basal cortisol and basal testosterone jointly predict changes in salivary testosterone after social victory in men. Psychoneuroendocrinology, 37(11), 1855–1865. Zilioli, S., & Watson, N. V. (2014). Testosterone across successive competitions: Evidence for a ‘winner effect’ in humans? Psychoneuroendocrinology, 47, 1–9.

market-mode behaviors. Psychological Science, 27(3), 331–344. Geniole, S. N., Bird, B. M., Ruddick, E. L., & Carré, J. M. (2017). Effects of competition outcome on testosterone concentrations in humans: An updated meta-analysis. Hormones and Behavior, 92, 37–50. Giddens, J. L., Schermer, J. A., & Vernon, P. A. (2009). Material values are largely in the family: A twin study of genetic and environmental contributions to materialism. Personality and Individual Differences, 46(4), 428–431. Hayes, A. F. (2013). Introduction to mediation, moderation, and conditional process analysis: A regression based approach. New York, NY: The Guilford Press. Holt, C. A., & Laury, S. K. (2002). Risk aversion and incentive effects. American Economic Review, 92(5), 1644–1655. van Honk, J., Schutter, D. J., Hermans, E. J., Putman, P., Tuiten, A., & Koppeschaar, H. (2004). Testosterone shifts the balance between sensitivity for punishment and reward in healthy young women. Psychoneuroendocrinology, 29(7), 937–943. Hyun, N. K., Park, Y., & Park, S. W. (2016). Narcissism and gift giving: Not every gift is for others. Personality and Individual Differences, 96, 47–51. Kniffin, K. M. (2006). Show me the status: Money as a kind of currency. Behavioral and Brain Sciences, 29(2), 188–189. Krishna, A. (2016). A clearer spotlight on spotlight: Understanding, conducting and reporting. Journal of Consumer Psychology, 26(3), 315–324. Krizan, Z., & Bushman, B. J. (2011). Better than my loved ones: Social comparison tendencies among narcissists. Personality and Individual Differences, 50(2), 212–216. Lakey, C. E., Rose, P., Campbell, W. K., & Goodie, A. S. (2008). Probing the link between narcissism and gambling: The mediating role of judgment and decision-making biases. Journal of Behavioral Decision Making, 21(2), 113–137. Lea, S. E., & Webley, P. (2006). Money as tool, money as drug: The biological psychology of a strong incentive. Behavioral and Brain Sciences, 29(02), 161–209. Lobbestael, J., Baumeister, R. F., Fiebig, T., & Eckel, L. A. (2014). The role of grandiose and vulnerable narcissism in self-reported and laboratory aggression and testosterone reactivity. Personality and Individual Differences, 69, 22–27. Marshall, T. C., Lefringhausen, K., & Ferenczi, N. (2015). The big five, self-esteem, and narcissism as predictors of the topics people write about in Facebook status updates. Personality and Individual Differences, 85, 35–40. Mazur, A., & Booth, A. (1998). Testosterone and dominance in men. Behavioral and Brain Sciences, 21(03), 353–363. McCaul, K. D., Gladue, B. A., & Joppa, M. (1992). Winning, losing, mood, and testosterone. Hormones and Behavior, 26(4), 486–504. Mehta, P., & Josephs, R. (2006). Testosterone change after losing predicts the decision to compete again. Hormones and Behavior, 50(5), 684–692. van der Meij, L., Buunk, A. P., van de Sande, J. P., & Salvador, A. (2008). The presence of a woman increases testosterone in aggressive dominant men. Hormones and Behavior, 54(5), 640–644. Morf, C. C., & Rhodewalt, F. (2001). Unraveling the paradoxes of narcissism: A dynamic self-regulatory processing model. Psychological Inquiry, 12(4), 177–196. Nepomuceno, M. V., Saad, G., Stenstrom, E., Mendenhall, Z., & Iglesias, F. (2016). Testosterone & gift-giving: Mating confidence moderates the association between digit ratios (2D: 4D and rel2) and erotic gift-giving. Personality and Individual Differences, 91, 27–30. Nicholls, E., & Stukas, A. A. (2011). Narcissism and the self-evaluation maintenance model: Effects of social comparison threats on relationship closeness. The Journal of Social Psychology, 151(2), 201–212. Pincus, A. L., Ansell, E. B., Pimentel, C. A., Cain, N. M., Wright, A. G., & Levy, K. N. (2009). Initial construction and validation of the pathological narcissism inventory. Psychological Assessment, 21(3), 365–379.

114