Science & Technology - Posted by David Orenstein-Brown on Friday, April 22, 2011 13:00 - 6 Comments 
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(2 votes, average: 5.00 out of 5) Loading ...Advice vs. experience: Divergent paths
It may seem like having the genes to follow advice over experience could make people dangerously oblivious to reality, but there may be a good reason for brains to be hardwired that way: Advice is usually convenient and often right. (Credit: iStockphoto)
BROWN (US) — Setting aside advice and following what has been learned from experience, or believing advice even when experience contradicts it, comes down to genetics.
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The text of this article by Futurity is licensed under a Creative Commons Attribution-No Derivatives License.
A new study finds that two brain regions have different takes on how incoming information should influence thinking.
The prefrontal cortex (PFC), the executive area of the brain, considers and stores incoming instructions such as the advice of other people, for example, “Don’t sell those stocks.” The striatum, buried deeper in the brain, is where people process experience to learn what to do, for example, “Those stocks often go up after I sell them.”
Details are published in the Journal of Neuroscience.
Michael Frank, assistant professor of cognitive, linguistic, and psychological sciences at Brown University, has been curious about the effect that the advice-influenced PFC has on the striatum’s 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,” says lead author Bradley Doll, a graduate student in Frank’s lab. “It biases what people learn about the contingencies they are actually experiencing.”
Frank and Doll 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 learn more quickly from experience when no advice is given, but also are more readily impressionable to the bias of the PFC when instruction is given.
Like a “yes man” who is flexible to a fault, the striatum gives more weight to experiences that reinforce the PFC’s belief, and less weight to experiences that contradict it. Researchers call this confirmation bias, and it is ubiquitous across many domains, including astrology, politics, and even science.
“People will distort what they experience to be perceived as more consistent with what they thought already,” Franks says.
To conduct the experiment, more than 70 people 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.
A mathematical model showed that the extent of this confirmation bias on learning depended on 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 says 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 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 genes lead to maladaptive performance, but that’s actually reflective of a system that evolved to be that way for an adaptive reason,” Frank says.
“This phenomenon of confirmation bias might actually just be a byproduct of a system that tries to be more efficient with the learning process.”
Researchers from the University of New Mexico contributed to the study, that was funded by the National Institutes of Health.
More news from Brown University: http://news.brown.edu
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6 Comments
Nergol
A load of shit sounds right to me as well.
For one thing, early experiences and learning from them may depend more on circumstances beyond our control than on the inner controls supposedly already there in our genes. Otherwise it’s like saying we have instincts that are not amenable to adjustments from experience. Or instincts that were selected from random accidents of mutation instead of through instructive adaptations provided from a variety of our species past experiences.
Brain chemicals don’t produce confidence for their purposes. Self confidence is gained by degrees from experience and it uses the chemical functions of the brain accordingly.
Melissa
I find it funny that people like to trash a study — and science in general — based on their perceptions of a quick summary… The point of this research, from what I can tell, is not at all that people’s behaviors are “unchangeable” or would “never alter over time” because of their genes. First, different genes contribute to (but don’t determine all on their own) different kinds of choice tendencies, and this shouldn’t be all that surprising any more than the claim that people from the same families have a greater chance as having some shared personality traits, intelligence, etc (this is well established). This research goes beyond that general claim to identify specific genes that influence brain function in one way or the other. Second (and maybe more importantly), the whole point of the article is that the genes *don’t* make our behaviors unchangeable or somehow determine them directly, but instead they influence the brain’s learning process (the degree to which behaviors do alter over time, either because of the advice or because of the experience after that). Of course it is possible that the lab computer tests they used don’t apply in the same way or to the same extent in the real world, but then again, who knows… that’s what basic science is for. And at least one of these genes is related to real-world bad decisions, like drug addiction. see here: http://www.pharmagateway.net/ChapterPage.aspx?DOI=10.1007/978-0-387-76678-2_1
The bone of contention s not about the role played here by genes but why they play it. Which whoever wrote this article either got backwards, or bought into something the experimenters themselves got backwards.
Which would seem to be the outdated scientific assumption that genetic algorithms are stochastically selected.
Andrew Turvey
If one way was always better than the other, evolution would make it prevalent. The more interesting question is why do both persist? Is it advantageous to have both types present in a community?
In addition, it’s worth noting that accepting advice, even if “wrong” can be positive in terms of group cohesion.
I don’t know what the point was of that last comment, except that if it was regarding the theory of instructive adaptations, it appears that if correct, then it was always prevalent, because it is inclusive of some mutations necessarily being accidental, while the former theories of selection have been exclusive of instructive means of adaptation.
What a load of shit. If it were as simple as genetics, people’s attitudes towards things like whether to follow advice or their own experience would be unchangeable – they would never alter over time. It would also be impervious to lessons learned in childhood from parents, teachers, and peers. But this is obviously not the case. People mature, and their attitudes change. They follow bad advice a few times, and become more cautious about it. They remember their mothers telling them to “follow your heart” or to “listen to the experts”. They read a novel in which a character follows bad advice, or fails to follow good advice, and it changes the way they live their own lives. This kind of “science” is what happens when people spend too much time around computers and MRI machines, and not enough time talking to actual human beings. Get out of the lab and go hang out with real people, guys.