Testosterone Administration Decreases Generosity in the Ultimatum Game

How do human beings decide when to be selfish or selfless? In this study, we gave testosterone to 25 men to establish its impact on prosocial behaviors in a double-blind within-subjects design. We also confirmed participants' testosterone levels before and after treatment through blood draws. Using the Ultimatum Game from behavioral economics, we find that men with artificially raised T, compared to themselves on placebo, were 27% less generous towards strangers with money they controlled (95% CI placebo: (1.70, 2.72); 95% CI T: (.98, 2.30)). This effect scales with a man's level of total-, free-, and dihydro-testosterone (DHT). Men in the lowest decile of DHT were 560% more generous than men in the highest decile of DHT. We also found that men with elevated testosterone were more likely to use their own money punish those who were ungenerous toward them. Our results continue to hold after controlling for altruism. We conclude that elevated testosterone causes men to behave antisocially

Have the Implications of Twin Deficits Changed?: Sudden Stops over Decades

Currency crisis, Lawson’s doctrine, Sudden stops, Twin deficits, F21, F3, F43, G15,

Scale effect of T on generosity.

<p>T levels and generosity for those on placebo are shown in blue, generosity for those on Androgel® are shown in red. (A) The reduction of generosity for those on Androgel® positively scales with levels of total T, free T and DHT; the relationship for DHT is shown (r = −0.3063, p = 0.0001). Men in the lowest decile of DHT had average generosity of $3.65 compared to generosity of$0.55 for men in the highest decile of DHT (85% lower). (B) The punishment threshold also scales with a man's level of total T, free T and DHT; the relationship for DHT is shown (r = 0.2284, p = 0.0011). Men in the lowest decile of DHT had average punishment threshold of $2.15 compared to a punishment threshold of$4.00 for men in the top decile of DHT (86% higher).</p