Oxytocin has been a well-studied hormone and neurotransmitter by scientists for years. The hormone is released when a woman is in labor, facilitating birth, and breastfeeding. Both sexes release oxytocin during an orgasm and is believed to increase pair bonding and social recognition. Usually, individuals with higher levels of oxytocin has more empathy and trust as well as lower social anxiety and fear response. Now, oxytocin may have a new role.

New research, published in the journal Proceedings of the National Academy of Science, suggests that oxytocin can make people more dishonest when their lies serve the interests of their group.

“This is the best evidence yet that oxytocin is not the ‘moral molecule,’” said co-leader Carsten de Dreu from the University of Amsterdam, “It doesn’t make people more moral or immoral. It shifts people’s focus from themselves to their group or tribe.”

The work of researchers from the Ben-Gurion University (BGU) of the Negev in Israel and the University of Amsterdam in the Netherlands focuses on ethical decision making. They selected a group of 60 individuals to receive either a dose of oxytocin or a placebo, and were split into teams of three.

The participants were asked to predict the results of 10 coin tosses and to state whether they had guessed correctly, once they saw the outcome. A correct answer could gain them money, lose them money, or do nothing, and any winnings or losses would be divided evenly between the three anonymous teammates. 

Among the individuals who received the placebos, 23 percent claimed to have guessed the results of nine or 10 of the coin tosses. However, those who sniffed oxytocin were even more dishonest. In the oxytocin group, 53 percent of the participants claimed to have correctly guessed this many coin tosses. 

"The statistical probability of someone correctly guessing the results of nine or 10 coin tosses is about 1%," says Dr. Shaul Shalvi, director of BGU's Center for Decision Making and Economic Psychology. "Yet, 53% of those who were given oxytocin claimed to have correctly predicted that many coin tosses, which is extremely unlikely."

"Our results suggest people are willing to bend ethical rules to help the people close to us, like our team or family," says Dr. Shalvi. "This raises an interesting, although perhaps more philosophical, question: are all lies immoral?"

De Dreu believes that oxytocin causes a shift in human beings from self-interest to group-interest. Therefore, is oxytocin the “moral” molecule?

Additional Resource:

Oxytocin promotes group-serving dishonesty