Researchers have shown a link between testosterone levels in men and their willingness to stick to a task.

Psychologists, Keith Welker (Wayne State University, Detroit, MI) and Justin Carré (Nipissing University, North Bay, Ontario), showed that on average men with higher testosterone levels spent more time working on an unsolvable puzzle, a measure of persistence. This work is the first to suggest that testosterone levels may be linked to persistence behavior in men. Their report was published in April in the European Journal of Personality.

Testosterone is known to be associated with aggression and dominance, but in nonhuman animals (like chicks, rats, or mice), testosterone can also increase time spent searching for food or investigating social partners, which may be interpreted as persistence. In men, testosterone is known to fluctuate, most notably in the wake of a conflict, such that winners maintain high levels but losers typically show reduced levels of testosterone.

In this study, researchers compared the amount of time that 118 men spent trying to solve an unsolvable puzzle (tracing shapes on a computer screen), after they had either won, lost, or not competed in a prior number-tracing task. Changes in testosterone were measured using saliva samples. In contrast to their predictions, they observed no differences between “winners,” “losers,” and non-competing controls, but noted rather that regardless of previous conflict, baseline testosterone levels predicted how long an individual would spend working on the unsolvable puzzles.

The authors admit that their inability to document any differences in persistence between winners and losers may reflect flaws in their experimental competition, and they suggest that future research should still consider the fluctuations in testosterone known to occur following similar conflicts.

The authors point out that persistence can make the difference between success and failure, with more persistent individuals less likely to be deterred from their goals by failure or difficulties, but that it can also be unproductive and a stubborn waste of time and energy. The experimental results suggest that testosterone may be an important predictor of persistence, but that other personality and contextual effects may dictate where and when that persistence occurs.

Indeed high levels of testosterone have also been linked to a reduced willingness to cooperate (a reduced persistence in social partnerships), and previous research has noted that men with higher levels of testosterone tend to hold lower levels of occupational status. Future research is needed to identify those factors that control the contexts where one is more likely to persist, and whether testosterone’s effect on persistence can contribute to, for example, career success.