New research ties a higher level of testosterone to a higher level of honesty.

In experiments, researchers from the University of Bonn showed that men who had received a dose of testosterone “clearly” lied less frequently than men who had received a placebo.

The scientists recruited 91 healthy men and about half, or 46, were treated with testosterone by applying it to the skin in gel form. On the following day, endocrinologists from the Bonn University Hospitals checked whether the blood testosterone levels were higher in these subjects than in the placebo group.

The other 45 test subjects received a placebo gel. Neither the subjects or the scientists knew who had received the testosterone, noted lead author Dr. Matthias Wibral.

The test subjects then played a simple game of dice in separate booths. The higher their scores, the higher the amounts of money they received as a reward.

“These experiments were designed such that the test subjects were able to lie,” said Dr. Bernd Weber, a neuroscientist from the Center for Economics and Neuroscience (CENS) at the University of Bonn. “Due to the separate booths, nobody knew whether they were entering their real scores into the computer, or higher ones in order to get more money.”

However, the scientists were able to determine later whether the test subjects had cheated or not.

“Statistically, the probability for all numbers on the dice to occur is identical,” Weber said, “so, if there are outliers in the higher numbers, this is a clear indication that subjects have been cheating.”

The researchers compared the results from the testosterone group to those from the control group. “This showed that the test subjects with the higher testosterone levels had clearly lied less frequently than untreated test subjects,” reported economist Dr. Armin Falk, who is one of the CENS co-directors. “This result clearly contradicts the one-dimensional approach that testosterone results in anti-social behavior.”

The researchers note that the hormone testosterone stands for typically male attributes as it fosters the forming of the sexual characteristics, increases libido and muscle building.

“Testosterone has always been said to promote aggressive and risky behavior and posturing,” Weber said.

In deciphering what the study results mean, Falk hypothesizes that it is likely the hormone increases pride and the need to develop a positive self-image.

“Against this background, a few euros are obviously not a sufficient incentive to jeopardize one’s feeling of self-worth,” he said.

The results were published in the Public Library of Science’s international online journal PLoS ONE.

Source: University of Bonn

Testosterone Seems to Boost Honesty