Testosterone has been associated with economically egoistic and materialistic behaviors, but -defensibly driven by reputable status seeking- also with economically fair, generous and cooperative behaviors. Problematically, social status and economic resources are inextricably intertwined in humans, thus testosterone’s primal motives are concealed. We critically addressed this issue by performing a placebo-controlled single-dose testosterone administration in young women, who played a game of bluff poker wherein concerns for status and resources collide.
We created a computerized version of a zero-sum (i.e. one player’s loss is the other player’s gain) two-person poker game based on the seminal work of Von Neumann and Morgenstern. The profit-maximizing strategy in this game is to mislead the other players by bluffing randomly (independent of strength of the hand), thus also when holding very poor cards (cold bluffing). The profit-maximizing strategy also dictates the players in this poker game to never call the other players’ bluffs. For reputable-status seeking these materialistic strategies are disadvantageous.
Twenty female volunteers (age range, 18-30) participated in this double-blind, crossover and within-subject study. Participants received a single dose of 0.5 mg sublingual testosterone in one session and placebo in the other session, with a 7-day latency between sessions. They received payment consisting of €10 as a fixed fee plus earnings depending on their performance in the poker game. We controlled for influences of hormonal change related to menstrual cycle by including only women who used single-phase contraceptives (with 0.15 mg levonorgestrel and 0.03 mg ethinylestradiol), and tested them during the 3-week period they were using these contraceptives, but not during menstruation. We exclusively recruited women because the parameters (quantity and time course) for inducing neurophysiological effects after a single sublingual administration of 0.5mg of testosterone are known in women but not in men.
A publication based on these data:
Van Honk, J. et al. Effects of Testosterone Administration on Strategic Gambling in Poker Play. Sci. Rep. 6, 18096; doi: 10.1038/srep18096 (2016).
