Hope you were nice to your mom on Mother's Day, because it turns out she was right all along: Hanging out with the wrong crowd can lead you to make bad decisions, and for the first time an ASU researcher has proved it and provided a theory to explain why.

A new study from post-doctoral researcher Goekhan Aydogan published in Psychological Science, found that conformity is enhanced by oxytocin, a naturally occurring hormone, and that the enhancement has a detrimental effect on honesty and moral values in a .

Aydogan's study builds on previous research, which also found that oxytocin increased conformity. He took a step further by proving that it leads to an increase in immoral behavior.

"This is the first study to show that peer pressure has a detrimental effect on ," he explained.

Oxytocin is released into the brain and the bloodstream as a result of various social stimuli, such as a baby crying or a friendly face, and it has a variety of effects, not all of which are known or understood.

In women who have just given birth, it is believed oxytocin is released to enhance bonding between her and the baby, prompting some to refer to it as the "cuddle" hormone, or the "love" hormone.

But that doesn't paint the whole picture, Aydogan points out, given its connection to conforming behavior.

"You can think of oxytocin like a mechanism that bonds group members together," he said.

With that in mind, Aydogan and his team designed an experiment in which 60 participants were given a dose of oxytocin via , and 60 participants were given a placebo via nasal spray. They were then asked to privately flip a coin and report whether it landed on heads or tails—heads resulted in a monetary reward.

Because the participants were the only ones who saw the result of the coin flip, they could lie without detection in order to receive the monetary reward. By comparing the reported outcomes of all the participants with their statistical chance implied by a fair coin, researchers were able to assess honesty on an aggregate level. However, researchers did not find a significant difference in lying about the results between the participants who had received oxytocin and the participants who had received a placebo.

Participants then performed the coin-tossing task again, this time with the opportunity to receive a greater monetary reward if they performed better than a competitor. In this case, researchers found that participants who had received oxytocin lied more about the coin flip results than those who had not.

Aydogan provides athletes as real-world examples. Despite the serious consequences, many cheat by doping because they believe that close peers and rivals do, too.

If, as Aydogan presumes, athletes release —the group bonding hormone—as a result of interacting with those peers in a competitive environment, they will become more likely to engage in conforming behavior, even if it would otherwise be considered immoral.

"If you assume everyone else is using performance enhancing drugs, then you … might perceive this as not immoral anymore because everyone else is doing it," Aydogan said. "So a kind of new norm is created where everyone is using ."

The results of the study have implications for policymakers and those in position of power, Aydogan said.

"It's extremely important to communicate that if you observe fraudulent behavior—like doping or tax evasion—that it is not common practice," he said.

But it's also important to prevent the situation in the first place: "At the same time, what you want to do is appeal to the moral code of people. Appeal to their personal responsibility. Like in elementary school, if someone jumps out of window, would you jump as well? This is basically the idea: Don't do it just because everyone does it."

More information: Gökhan Aydogan et al. The Detrimental Effects of Oxytocin-Induced Conformity on Dishonesty in Competition, Psychological Science (2017). DOI: 10.1177/0956797617695100

Journal information: Psychological Science