When it comes to sharing, it’s often assumed that women are more generous than men and loads of research supports this. A new study in Nature Human Behavior shows yet again that women are nicer but goes further and finds that men and women’s brains react differently to selfless behavior.
“The brain data provide a deeper understanding for why women often act more pro-socially [generously] than men,” Alexander Soutschek, an author of the study and post-doctoral researcher at the University of Zurich, told TODAY via email.
Women’s striatum, the brain’s reward center, activate when women act generously. When men act selfishly their striatum flickers with action. This means men and women receive an internal reward for behaving a certain way. While this provides new insight into altruism, Soutschek said the research does not indicate that men and women are born with unique brains.
“It would be a fallacy to conclude that a ‘biological difference’ in brain functioning implies that this difference is innate or has evolutionary origins,” he said.
To understand how the brain works when a person acts selfishly or generously, the researchers staged two experiments. In the first, 27 females and 28 males, of college age, participated in a game where they decided to keep more money for themselves or accept less money but share it with another person. During this exercise, the researchers monitored their brain activity with a functional magnetic resonance machine (fMRI).
When women shared, their striatum activated. And, when men kept the money their striatum engaged. Later, participants played the game again after taking a drug that suppresses dopamine, a neurotransmitter involved in the body’s reward system. In these conditions, when women acted more selfishly they experienced activity in the striatum. When men acted generously their striatum lit up with activity.
The researchers believe this shows that men and women learn how to act, which influences how the brain rewards them.
“If our explanation is correct, then our study shows how influential gender stereotypes are in our society and that they even lead to gender differences in the brain,” Soutschek said.
Women punished for selfish behavior
Linda Carli, who did not participate in the study, said the findings bolster what experts know about men and women and selfish and generous behavior. But she wonders why the differences exist and thinks it is more than just dopamine.
“It’s very sexy stuff these brain differences in men and women,” said the senior lecturer of psychology at Wellesley College. “Dopamine in this context, it is more complicated.”
She said lots of research shows that women who act selfishly are punished for that behavior, while men are rewarded. And, it could be that learning from real-life experiences changes the brain structure, said Dr. Susanne Ahmari, who didn’t participate in the study.
“Systems involved in reward are malleable over time. They can absolutely be susceptible to learning changes,” said the assistant professor of psychiatry at the University of Pittsburgh.
While more research conducted to understand this, Ahmari said that studies examining the differences between men and women help experts better understand how mental illness presents in men and women.
“We are now finding out very interesting things between males and females and both performance of behaviors of normal conditions and behaviors in mental illness,” she said.