Last night Dr. Joseph Kable spoke in a preceptorial on neuroeconomics. Some of his own work has focued on impulsivity, self-control, and future decision making. In the preceptorial Dr. Kable addressed how people make choices, citing a host of studies that have lent insight to the psychology of judgment and decision-making. Starting with a study on the price of wine on Brain Activity and Experienced Pleasantness by Dr. Hilke Plassmann. In this study fMRI was taken as participants tasted wines that they were told were $10 or $90 bottles. “Our results show that increasing the price of a wine increases subjective reports of flavor pleasantness as well as blood-oxygen-level-dependent activity in medial orbitofrontal cortex, an area that is widely thought to encode for experienced pleasantness during experiential tasks.”
The people in Dr. Plassmann’s studies weren’t the only ones fooled by experimenters (we're all so predictable!). Dr. Kable and the members of the neuroscience honors society, who organized the event, ran their own experiment on the participants at the preceptorial. The event featured gelato, a strong incentive for many attendees. Before scooping their gelato participants were told to taste four different types of vanilla. They laid out four different bowls, the first two had no label, the third was labeled capa giros and the fourth was labeled fro yo. It was a difficult decision but I chose the fourth one because I love the taste of yogurt. What we didn’t know however was that the first two unlabeled ones were the same two flavors from capa giros and fro yo. Once everyone had made their choices and they were tallied up Dr. Kable revealed that overwhelmingly the group had chosen one of the labeled options (the labeled capa giros was the favorite). He attributed this to people’s preference for labels which we assume informs us of the quality of a product.
Another interesting topic Dr. Kable discussed was reward-seeking behavior. Many of you may have heard that dopamine is the pleasure chemical, rewarding behaviors such as eating and sex. Most drugs of abuse activate the dopamine reward system, which has its densest projections in the striatum. Dr. Kable explained how the role of dopamine is actually more complex than simply signaling pleasure. Research has shown that dopamine activity reflects the difference between expected reward and actual award. By this logic, if you do not expect a reward and receive one, you will have a spike in activity of dopaminergic neurons. If you expect a reward and receive one, you will stay at baseline levels of dopamine activity. Lastly, if you expect a reward and do not receive one, you will have a drop in dopamine activity. It seems at dopamine plays a major part in reward learning and conditioning.
Lastly, Dr. Kable gave a few examples of how researchers have used data on brain activity to predict preferences, although he notes often a survey will give more accurate results. In one study participants were presented a series of pictures of cars and asked afterwards “would you buy this car?”. One group of participants was told to pay close attention others were told not to. For both groups using images of activity in the medial prefrontal cortex, researchers were able to predict participants responses at above chance levels (approximately 75% accuracy). In another study a researcher at Emory named Gregory Berns measured brain activity through fMRI in subjects while they listened to unknown bands whose music he had found on myspace. Returning to the data years later he found a positive correlation between ventral striatal activity and album sales. In this study it seems it could have been possible to predict future cultural popularity of a band based on neural activity. Lastly, he posed the question can neuroscience help us to design better movies? A researcher put people in a scanner had them watch The Good, the Bad, and the Ugly, a Clint Eastwood western. He compared brain activity between different subjects during the movie and found there was a substantial correlation in activity between subjects watching the same movie. Apparently the movie stimulation was causing “synchronization” of brain activity across subjects. He compared synchronization during several well-respected films and a random montage of clips of people on the street he had put together. A film by Alfred Hitchcock produced the most synchronization while the random film produced nearly no synchronization. This study suggests that a good director is controlling what their audience is paying attention to, looking at, and thinking about, such that two people will be thinking the same thing to cause similar brain activity.
Dr. Kable also presented at TEDx Penn this October and will be teaching a neuroeconomics class this spring (BIBB473). To learn more about some of the studies check out the links below!
On wine:
http://www.pnas.org/content/105/3/1050.full
On predicting future popularity of bands:
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