Risky Gambling Influenced by Single Brain Connection

One person’s risky bet is another’s exciting opportunity. The difference, according to new research, is in our brains.

A new study from Stanford University has found that people with a stronger connection between two brain regions have a more cautious financial outlook.

“Activity in one brain region appears to indicate ‘uh oh, I might lose money,’ but in another seems to indicate ‘oh yay, I could win something,'” said Dr. Brian Knutson, an associate professor of psychology. “The balance between this ‘uh oh’ and ‘oh yay’ activity differs between people and can determine the gambling decisions we make.”

While researchers have tracked activity in those two brain regions — the anterior insula and nucleus accumbens — for the past decade, Knutson was curious how the two work together. He wondered are they directly connected, or do they influence a different brain region that makes the ultimate decision?

To find out, Knutson and his research team employed a technique called diffusion-weighted MRI developed at Stanford that identifies tracts of neurons that connect brain regions and measures the strength of those connections in terms of how insulated they are.

Using the new technique, Knutson and graduate student Josiah Leong found a tract that directly connects the anterior insula and nucleus accumbens; something that had been seen before in animals but never in humans.

They also found that the thicker the sheath of fatty tissue insulating the bundle — an indicator of the strength of the connection — the more cautious the study participants’ decisions were in a gambling test.

The neuronal connection appears to be a conduit for the more cautious brain region to dampen activity in the more enthusiastic region, the researchers explain in the study, published in the journal Neuron.

“Most people love the small chance of a huge win,” Knutson said. “But people vary. Some people really, really like it. But people who have a stronger connection don’t like it as much.”

For the study, the researchers gave each participant $10 that they could gamble — or not — in a series of games with different odds. The participants got to keep any money left at the end of the experiment.

When participants entered an MRI chamber they could see a roulette wheel and the odds for winning or losing. In one bet, they might have equal odds to win or lose three dollars. In another, they might have higher odds of winning a small amount and small odds of losing a lot or vice versa.

As the participants weighed the various bets, the researchers tracked activity in the two brain regions. The team noticed that all gamblers — even the cautious ones with a well-insulated connection — would sometimes place risky bets. And when they did, the more cautious region stayed quieter while the enthusiastic region grew more active.

“We could predict the person’s upcoming bet based on the balance of activity in these regions,” said Knutson.

The stronger, better insulated the connection between the regions, the less likely it was that the enthusiastic region would become active at the prospect of a large but unlikely win, the study found.

Knutson acknowledges that finding the connection between the two regions won’t immediately lead to new interventions for people with gambling problems or other issues relating to risky choices, but it does provide a starting point.

“Now we can start asking interesting questions about impulse control and gambling,” Knutson said. “For example, does the connection change over the course of therapy?”

Anything that strengthens the connection might potentially help people reduce risky decisions, whether in gambling, drug addiction or other potentially risky behaviors, he noted.

Source: Stanford University

Woman gambling photo by shutterstock.