'Love Hormone' May Trigger Jealousy, Too

Nov. 16 -- SUNDAY, Nov. 15 (HealthDay News) -- With a reputation as the "love hormone," oxytocin has been linked to trust, empathy and generosity.

But new research suggests that oxytocin plays a role in jealousy and gloating as well.

"Subsequent to these findings, we assume that the hormone is an overall trigger for social sentiments: When the person's association is positive, oxytocin bolsters pro-social behaviors; when the association is negative, the hormone increases negative sentiments," Israeli researcher Simone Shamay-Tsoory, of the University of Haifa, said in a news release from the university.

Scientists have linked the hormone to feeling good. It's released during childbirth and when people have sex. Research has found that people who inhaled a man-made form of the hormone were more altruistic.

But in earlier research, Shamay-Tsoory had discovered that mice who inhaled oxytocin were more aggressive so she decided to figure out if the hormone might have the same effect on people.

To do that, she had 56 people inhale a man-made version of the hormone or a placebo. They then played game designed to encourage feelings of envy and gloating.

Those who had inhaled oxytocin reported higher levels of envy and gloating during the game than the others, but not afterward.

The findings could have a cautionary message.

"Following the earlier results of experiments with oxytocin, we began to examine the possible use of the hormone as a medication for various disorders, such as autism," Shamay-Tsoory said. "The results of the present study show that the hormone's undesirable effects on behavior must be examined before moving ahead."

A report on the research appeared recently in the online issue of Biological Psychiatry.

More information

Colorado State University has more on oxytocin.

SOURCE: University of Haifa, news release, Nov. 11, 2009