Testosterone administration increases susceptibility to negative feedback after risky choices in men, according to the results of a new double-blind, placebo-controlled, randomized study. The research has been published in the scientific journal Biological psychology.
“There have been both correlational and experimental studies suggesting that testosterone is associated with risk-taking, although the evidence is mixed,” explained lead researcher Oshin Vartanian, a scientist who works at Defense Research and Development Canada, a special executive agency of the United States. the Canadian Ministry. of National Defense.
“Previously, we had conducted an fMRI study which showed that when it comes to making risky choices, people are more risk averse when they gamble with life than with money (Vartanian et al., 2011). We had attributed this difference to the greater value placed on human life than on money.”
“In the current experiment (which was part of a larger registered clinical trial), we were interested to see whether the administration of exogenous testosterone would affect people’s tendency to make risky choices, and whether the effect would be stronger for money than for lives because people appear to have a lower threshold to make risky choices in the former context.”
The data collected for this study was part of a larger study examining the impact of testosterone replacement on muscle mass and physical performance in healthy young men while experiencing a long-term energy deficit. The study included 50 healthy adult men who underwent severe exercise and diet-induced energy deficiency for 28 days, receiving either testosterone (200 mg per week) or placebo (sesame seed oil).
Before, during, and after the 28 days, participants completed a guessing task in a functional magnetic resonance imaging scanner. In the guessing task, participants had to repeatedly choose between a series of two options: one option had a definite outcome and the other had an uncertain outcome. The outcomes involved hypothetical human lives or cash. After selecting one of the options, the participants received feedback on their choice.
Testosterone did not seem to affect risky decision making in general. However, men who received testosterone were more likely to select the particular outcome after negative feedback about a risky choice compared to the control group.
“Our results did not support our prediction that testosterone promotes risky behavior, further weakening the evidence base for this idea in the literature,” Vartanian told PsyPost. “What testosterone did instead was make participants more sensitive to the outcomes of their risky choices. In particular, regardless of whether the context was lives or money, the testosterone group was more likely than the placebo group to prefer the sure option over the risky option immediately after negative feedback on a risky choice.
“Despite the mixed nature of previous evidence regarding the relationship between testosterone and risk-taking, we were nevertheless surprised that we observed no effect on risky choices in the current experiment,” added Vartanian. “Interestingly, a number of recent large-scale experimental studies and meta-analyses have come to a similar conclusion, prompting us to review our assumptions about the nature of this long-held assumption.”
In the games of chance task, the results were presented in terms of both profit and loss. Previous research has shown that humans are fewer are likely to make risky choices when outcomes are presented in terms of profit, but they are more are likely to make risky choices when the results are presented in terms of losses, even if the actual outcome is the same. This phenomenon is known as the reflection effect.
The researchers noted that the strength of this effect was related to different patterns of brain activity.
“There were large individual differences in propensity to make risky choices (regarding whether the gamble represented wins or losses), which in turn were related to variation in brain function in the dorsal thalamus – a region that controls emotion, reward and risks processed.” Vartanian explained. “More work is needed to determine exactly why this particular region is associated with individual differences in making risky choices involving both money and lives.”
But the study has two important caveats. “All our data has been collected from men and we know that there are hormonal differences between the sexes. As such, it’s unclear if a similar picture would emerge in women,” Vartanian noted.
In addition, the administration of testosterone in the current study was designed to return plasma testosterone to near-normal levels among participants in the experimental group.
“Our data was collected against the backdrop of severe energy deficiency, and because energy deficiency is associated with a reduction in circulating testosterone levels, our administration of exogenous testosterone should be viewed as a restorative intervention,” explains Vartanian. “As such, it remains unknown whether administration of exogenous testosterone above normal levels would influence risky choice as measured by our gambling task.”
The study, “Effect of exogenic testosterone in the context of energy deficit on risky choice: Behavioral and neural evidence from males,” is authored by Oshin Vartanian, Timothy K. Lam, David R. Mandel, Sidney Ann Saint, Gorka Navarrete, Owen T. Carmichael, Kori Murray, Sreekrishna R. Pillai, Preetham Shankapal, John Caldwell, Claire E. Berryman, J. Philip Karl, Melissa Harris, Jennifer C. Rood, Stefan M. Pasiakos, Emma Rice, Matthew Duncan, and Harris R Liebermann .