Why you should go with your gut feeling

Next time you’re at a blackjack table trying to decide whether to hold or hit, just trust your gut. New research shows that our brains pick up on subliminal signals – a dealer’s tell, for instance – when making risky decisions.

“When you think that you are referring to your intuition, actually you just learn an association between subliminal signals in your context and the outcome of your actions,” says Mathias Pessiglione, a neuroscientist at the Centre for Neuroimaging Research in Paris, France, who led the study.

Doctors and gamblers may be used to trusting their instincts in make-or-break situations, but scientists have had a tough time proving that the brain can learn subconsciously.

To uncover this ability, Pessiglione and colleague Chris Frith, of University College London, tested 20 volunteers with a simple game based on winning and losing small amounts of money.

On a computer screen, the volunteers watched an animated abstract pattern for a few seconds, which included one of three symbols part way through. Unbeknownst to the subjects, the symbols indicated whether they would lose or gain £1 or break even if they accepted the gamble.

Gut feeling wins

“You just see some flickering pattern,” Pessiglione says. Volunteers then had three seconds to decide whether to take the bet. “We just told the subjects to follow their intuition or gut feeling,” he says.

Surprisingly, subjects got better at predicting whether they would win or not, eventually plateauing at slightly above chance, strong evidence that volunteers do not consciously notice the symbols but are affected by them nonetheless.

“If you are conscious, you win much more money, but you can still win money if you cannot consciously perceive the cues,” Pessiglione says.

Under a functional-MRI brain scanner, the researchers found that the subjects appeared to be basing their subconscious choices on activity in an area of their brains involved in conscious risk-taking – the striatum. During the game, a part of the brain involved in processing vision lit up, but only after the activity in the striatum. Pessiglione hypothesises that the striatum tells the vision-processing part of the brain how to pick up on the subliminal symbols linked to winning and losing.

On a hunch

“This might now provide an explanation why we often base our decisions on intuitive hunches where a certain option somehow feels right,” says John-Dylan Haynes, a cognitive neuroscientist at the Bernstein Center for Computational Neuroscience in Berlin, Germany.

“But we shouldn't be worried that we could be influenced against our will by such unconscious processes: the study shows that the unconscious brain is intelligent enough to select the best options,” he says.

Pessiglione, too, is not planning to use his team’s findings to hawk shampoos, cars or presidential candidates. “Our prospect is not to help advertisers take advantage of consumers,” he says.

Journal reference: Neuron (DOI: 10.1016/j.neuron.2008.07.005)