Gentle electrical stimulation applied to specific areas of the brain can increase a person’s willingness to share money with others, even at a personal cost, according to a new study. Researchers at the University of Zurich and East China Normal University found that synchronizing activity in the frontal and parietal lobes with a weak electrical current prompted participants to build more altruistic choices in a behavioral economics game.
The study, published in the journal PLoS Biology, involved 44 participants who played a modified version of the “Dictator Game.” In this game, individuals are given a sum of money and tasked with deciding how much, if any, to share with an anonymous recipient. Researchers varied the amount of money available in each round, allowing participants to potentially benefit more or less than their counterpart. While playing, participants received transcranial alternating current stimulation (tACS) – a non-invasive technique delivering a mild electrical current to the scalp – targeting the frontal and parietal lobes.
Researchers had previously identified these two brain regions as key players in the neural circuitry of altruistic behavior. Earlier monitoring of brain activity during the Dictator Game revealed increased communication between the frontal and parietal lobes when participants chose to give away more money. The current study aimed to establish a causal link between activity in these areas and selfless decision-making.
“When we altered communication in a specific brain network using targeted, non-invasive stimulation, people’s sharing decisions changed – shifting how they balanced their own interests against others,” explained Dr. Jie Hu, a professor at East China Normal University and co-author of both studies. The electrical stimulation, described by one participant as feeling “like a warm shower or small drops of rain,” appeared to enhance the synchronization between the frontal and parietal lobes.
“Statistically, we really see an increase in their willingness to pay,” said Christian C. Ruff, a professor of neuroeconomics and decision neuroscience at the University of Zurich and co-author of the study. “The effects were not huge, but they’re consistent.” Professor Ruff told BBC Radio 4’s Inside Science that the consistent link between brain activity and altruistic behavior suggests that altruism may be “part of our biological nature.”
The findings build on recent research suggesting a biological basis for prosocial behavior. A report from Macao News highlighted the study’s findings, noting the potential implications for understanding the neurological underpinnings of altruism. Researchers believe that further investigation into these brain mechanisms could shed light on how to foster cooperation, particularly in scenarios where collective success depends on individuals prioritizing shared goals.
Professor Ruff indicated that understanding this mechanism “improves our basic understanding of how the brain supports social decisions, and it sets the stage for future research on cooperation – especially in situations where success depends on people working together.” The research team has not yet announced plans for follow-up studies, but the findings are expected to stimulate further investigation into the neural basis of human social behavior.
