Advice vs. experience: Genes predict learning style

April 19, 2011, Brown University

Researchers at Brown University have found that specific genetic variations can predict how persistently people will believe advice they are given, even when it is contradicted by experience.

The story they tell in a paper in the April 20 issue of the is one of the byplay between two that have different takes on how incoming information should influence thinking. The (PFC), the executive area of the brain, considers and stores incoming instructions such as the advice of other people (e.g., "Don't sell those stocks.") The striatum, buried deeper in the brain, is where people process experience to learn what to do (e.g., "Those stocks often go up after I sell them.")

Researchers including Michael Frank, assistant professor of cognitive, linguistic, and psychological sciences at Brown, have studied the striatum intensely, but have been curious about the effect that the advice-influenced PFC has on its function. It turns out that in a learning task, people are guided more by advice at the start. Their genes determine how long it takes before they let the lessons of experience prevail.

"We are studying how maintaining instructions in the prefrontal cortex changes the way that the striatum works," said lead author Bradley Doll, a graduate student in Frank's lab. "It biases what people learn about the contingencies they are actually experiencing."

In their experiment, the researchers studied people with and without genetic variations that affected the activity of the neurotransmitter dopamine in the PFC and striatum. A variation in a gene called COMT that affects dopamine in the PFC, for example, helps people remember and work with advice.

People with a variation on the gene DARPP-32 that affects the response to dopamine in the stratium allowed people to learn more quickly from experience when no advice was given, but also made them more readily impressionable to the bias of the PFC when instruction was given. Like a "yes man" who is flexible to a fault, the striatum would give more weight to experiences that reinforced the PFC's belief, and less weight to experiences that contradicted it. Researchers call this confirmation bias, which is ubiquitous across many domains, such as astrology, politics, and even science.

"People will distort what they experience to be perceived as more consistent with what they thought already," said Frank, who is also affiliated with the Brown Institute for Brain Science.

To conduct the experiment, the researchers recruited more than 70 people who gave saliva samples and then performed a computerized learning task. The subjects were shown symbols on a screen and asked to pick the "correct" one, which they had to learn via feedback. Because the feedback was probabilistic, it was impossible to choose the correct symbol on every trial, but subjects could learn over multiple trials which of the symbols were more likely to be correct.

For some symbols, subjects were given advice about which answer was more likely to be correct. Sometimes that advice was wrong. Ultimately the people with particular genetic variants were the ones who stuck with wrong advice the longest, and in a later test they were more likely to choose symbols that they were advised were correct over those that in reality had higher likelihood of being correct. Using a mathematical model, the researchers found that the extent of this confirmation bias on learning depended on their genes.

Tradeoffs of adaptability

It may seem like having the genes for a strong-willed prefrontal cortex and an overly obsequious striatum could make people dangerously oblivious to reality, but Frank said there's a good reason for brains to be hardwired to believe in advice: Advice is often right and convenient.

People inclined to follow instructions from others, albeit to varying degrees based on their genes, can make sensible decisions much more quickly than if they had to learn the right thing to do from experience. In some cases (e.g., "Danger: high voltage") experience is a very dangerous way to learn. But in other cases (e.g. "The cable guy should be there at 1 p.m." or "This slot machine pays off"), believing in advice for too long is just foolish.

"It's funny because we are telling a story about how these lead to maladaptive performance, but that's actually reflective of a system that evolved to be that way for an adaptive reason," Frank said. "This phenomenon of confirmation bias might actually just be a byproduct of a system that tries to be more efficient with the learning process."

Related Stories

Recommended for you

How your brain remembers what you had for dinner last night

January 17, 2018
Confirming earlier computational models, researchers at University of California San Diego and UC San Diego School of Medicine, with colleagues in Arizona and Louisiana, report that episodic memories are encoded in the hippocampus ...

Recording a thought's fleeting trip through the brain

January 17, 2018
University of California, Berkeley neuroscientists have tracked the progress of a thought through the brain, showing clearly how the prefrontal cortex at the front of the brain coordinates activity to help us act in response ...

Midbrain 'start neurons' control whether we walk or run

January 17, 2018
Locomotion comprises the most fundamental movements we perform. It is a complex sequence from initiating the first step, to stopping when we reach our goal. At the same time, locomotion is executed at different speeds to ...

Miles Davis is not Mozart: The brains of jazz and classical pianists work differently

January 16, 2018
Keith Jarret, world-famous jazz pianist, once answered in an interview when asked if he would ever be interested in doing a concert where he would play both jazz and classical music: "No, that's hilarious. [...] It's like ...

New study reveals why some people are more creative than others

January 16, 2018
Creativity is often defined as the ability to come up with new and useful ideas. Like intelligence, it can be considered a trait that everyone – not just creative "geniuses" like Picasso and Steve Jobs – possesses in ...

A 'touching sight': How babies' brains process touch builds foundations for learning

January 16, 2018
Touch is the first of the five senses to develop, yet scientists know far less about the baby's brain response to touch than to, say, the sight of mom's face, or the sound of her voice.

2 comments

Adjust slider to filter visible comments by rank

Display comments: newest first

WarRoom
not rated yet Apr 19, 2011
I think advice is a good shortcut, but like Reagan said, trust but verify. A lot of what's in textbooks is never revisited and a lot of common knowledge among folks is never updated. Most people are surprised or don't believe that China has the only operating MagLev train.
pauljpease
not rated yet Apr 20, 2011
Reminds of the recent article showing a difference in brain regions between liberals and conservatives. I'd like to see a mash up between these studies. I have a feeling that people who are predisposed to believe what they're told might be more common towards one end of that spectrum.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.