In the end, the combination sex and advertising may work

Apr 4, 2008 19:16 GMT  ·  By

This is the recipe used by most commercials: put a hot babe near the product, everything from cars to pencils, and the men will buy it. Is it that easy? Partially yes, as revealed by a new Stanford study published in the journal "NeuroReport." Men may react like this in case of positive stimuli, especially if they are pressured. "In the immediate aftermath of that stimulation, men are consistently more likely to take bigger financial risks than they otherwise would. This is the first study to demonstrate that emotional stimuli can influence financial risk-taking," said lead author Brian Knutson, assistant professor of psychology. The team employed functional magnetic resonance imaging (fMRI) of the brains of subjects having to take quick gambling decisions at two levels of financial risk.

The same team had showed in 2005, based on fMRI of brain activity, that the nucleus accumbens of the brain was associated with risk and gambling behaviors. Avoiding the risk was associated with another nucleus, the insula.

"We didn't know is whether we could somehow control the activation in that area (nucleus accumbens) by presenting some completely irrelevant stimulus. And whether that would change activation in that area and actually change behavior," said Knutson.

Heterosexual male undergraduates were out to watch erotic images (triggering an elicit positive emotional response), snakes and spiders (for a negative response), and office supplies for a neutral response. When the volunteer regarded office supplies more repellent than snakes and spiders, he was put to rate each image after the scans, resulting personalized ratings for each subject, which properly correlated brain activation to the actual emotion of the subject.

After watching each image, the subjects had to immediately decide if they gambled one dollar or 10 cents, in a gambling that always had a 50-50 chance of winning or losing. The subject had received $10 for gambling before the beginning of the experiment.

"We wanted them to care. We took that money back if they lost it. What we saw is that when they viewed the erotic pictures, the activation in their nucleus accumbens increased compared to the other stimuli, and also that they had increased activation in that region before choosing the high-risk gamble," said Knutson.

Statistic analysis showed that the increase in gambling behavior was indeed connected to positive stimuli (erotic, in this case).

"After people had seen those erotic pictures, they tended to pick the high-risk gamble more often, especially if they had been picking the low-risk gamble before. The interesting finding from an economic standpoint is that these completely irrelevant stimuli, these pictures that have nothing to do with the gambles or the history of outcomes that people have experienced with these gambles, still influence behavior. They seem to do so at least partially by influencing activation of these brain regions," said Knutson.

These results go beyond gambling, explaining the targeting of the emotionally influenced responses, from advertising to politics. "If you go to the casinos, people are wearing skimpy costumes, they're giving you free alcohol, there are bells and lights and things like that, which don't necessarily seem related to the odds of the gambling. But these are cues that might activate brain regions that encourage risk-taking and therefore get people to gamble more," said Knutson. Indeed, the hot bimbo over the hood of the car could make you choose it. This happens in case they don't leave you time to think.

"It may work sometimes under some conditions. Our trials are happening relatively fast, changing on a second-to-second basis. We're forcing people to immediately make a decision, and the emotional stimuli appear in close temporal proximity to the decision itself. If you have these kinds of appeals, you'd better make it easy for people to make an immediate decision. You should put them under time pressure. It's an existence proof that some irrelevant emotional stimuli can influence some immediate financial decisions and that we can track down one brain basis for this influence," added Knutson.