Subscribe free to our newsletters via your
. Earth Science News .




ABOUT US
Suspicion resides in two regions of the brain
by Staff Writers
Roanoke, VA (SPX) May 28, 2012


Fool me once, shame on you. Fool me twice, shame on my parahippocampal gyrus. Read Montague, Ph.D., and colleagues at the Virginia Tech Carilion Research Institute discovered two distinct sites for suspicion in the brain: the amygdala, which correlates strongly with a baseline distrustfulness, and the parahippocampal gyrus, which acts like a cerebral lie detector. Credit: Virginia Tech

Scientists at the Virginia Tech Carilion Research Institute have found that suspicion resides in two distinct regions of the brain: the amygdala, which plays a central role in processing fear and emotional memories, and the parahippocampal gyrus, which is associated with declarative memory and the recognition of scenes.

"We wondered how individuals assess the credibility of other people in simple social interactions," said Read Montague, director of the Human Neuroimaging Laboratory and the Computational Psychiatry Unit at the Virginia Tech Carilion Research Institute, who led the study.

"We found a strong correlation between the amygdala and a baseline level of distrust, which may be based on a person's beliefs about the trustworthiness of other people in general, his or her emotional state, and the situation at hand. What surprised us, though, is that when other people's behavior aroused suspicion, the parahippocampal gyrus lit up, acting like an inborn lie detector."

The scientists used functional magnetic resonance imaging, or fMRI, to study the neural basis of suspicion. Seventy-six pairs of players, each with a buyer and a seller, competed in 60 rounds of a simple bargaining game while having their brains scanned. At the beginning of each round, the buyer would learn the value of a hypothetical widget and suggest a price to the seller.

The seller would then set the price. If the seller's price fell below the widget's given value, the trade would go through, with the seller receiving the selling price and the buyer receiving any difference between the selling price and the actual value. If the seller's price exceeded the value, though, the trade would not execute, and neither party would receive cash.

The authors found, as detailed in a previous paper, that buyers fell into three strategic categories: 42 percent were incrementalists, who were relatively honest about the widget's value; 37 percent were conservatives, who adopted the strategy of withholding information; and 21 percent were strategists, who were actively deceptive, mimicking incrementalist behavior by sending high suggestions during low-value trials and then reaping greater benefits by sending low suggestions during high-value trials.

The sellers had a monetary incentive to read the buyers' strategic profiles correctly, yet they received no feedback about the accuracy of the information they were receiving, so they could not confirm any suspicions about patterns of behavior.

Without feedback, the sellers were forced to decide whether they should trust the buyers based on the pricing suggestions alone. "The more uncertain a seller was about a buyer's credibility," Montague said, "the more active his or her parahippocampal gyrus became."

The authors believe a person's baseline suspicion may have important consequences for his or her financial success.

"People with a high baseline suspicion were often interacting with fairly trustworthy buyers, so in ignoring the information those buyers provided, they were giving up potential profits," said Meghana Bhatt, the first author on the research paper. "The ability to recognize credible information in a competitive environment can be just as important as detecting untrustworthy behavior."

The findings may also have implications for such psychiatric conditions as paranoia and anxiety disorders, said Montague. "The fact that increased amygdala activation corresponds to an inability to detect trustworthy behavior may provide insight into the social interactions of people with anxiety disorders, who often have increased activity in this area of the brain," he said.

The research appeared in the early online edition of the Proceedings of the National Academy of Sciences (PNAS) on May 10 in the article "Distinct contributions of the amygdala and parahippocampal gyrus to suspicion in a repeated bargaining game" by Meghana Bhatt, PhD, an assistant research professor at the Beckman Research Institute of the City of Hope Hospital in Duarte, Calif.; Terry Lohrenz, PhD, a research assistant professor in the Virginia Tech Carilion Research Institute; Colin F. Camerer?, PhD, the Robert Kirby Professor of Behavioral Economics at the California Institute of Technology; and Montague, PhD, the corresponding author, who is a professor of physics at the Virginia Tech Carilion Research Institute and in the College of Science at Virginia Tech. The research was supported by grants to Read Montague from the Wellcome Trust and the National Institutes of Health.

.


Related Links
Virginia Tech
All About Human Beings and How We Got To Be Here






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle








ABOUT US
Personality genes may help account for longevity
Bronx NY (SPX) May 28, 2012
"It's in their genes" is a common refrain from scientists when asked about factors that allow centenarians to reach age 100 and beyond. Up until now, research has focused on genetic variations that offer a physiological advantage such as high levels of HDL ("good") cholesterol. But researchers at Albert Einstein College of Medicine and Ferkauf Graduate School of Psychology of Yeshiva Unive ... read more


ABOUT US
Rescuers find first bodies at Pakistan avalanche site

Japan refused US offer of nuclear experts in PM office

Outside View: Refugees forever?

Spain cuts aid to Caribbean, S. America

ABOUT US
Mystifying materials

Just How Green is Google

'Metamaterials,' quantum dots show promise for new technologies

Thousands of invisibility cloaks trap a rainbow

ABOUT US
Deep sea animals stowaway on submarines and reach new territory

Japan pledges $500m for Pacific islands

Thousands of shellfish found dead in Peru

Latest Southern Ocean research shows continuing deep ocean change

ABOUT US
New Study by WHOI Scientists Provides Baseline Measurements of Carbon in Arctic Ocean

Illuminating the Ancient History of Circumarctic Peoples

Toxic mercury, accumulating in the Arctic, springs from a hidden source

Russia's Antarctic probes to be tested in Ladoga Lake

ABOUT US
Food, water safety provide new challenges for today's sensors

Commonly used pesticide turns honey bees into 'picky eaters'

DNA vaccine and duck eggs protect against hantavirus disease

Winemakers push China sales at top Asian wine fair

ABOUT US
Tropical Storm Beryl lashes southeast US coast

Storm threatens big US beach weekend

Tsunami debris includes toxic chemicals

Mexico on alert as hurricane Bud gathers force

ABOUT US
West African forces complete G.Bissau deployment

Former G.Bissau army chief, minister flee

G. Bissau army to return to barracks

Somali, AU troops close in on Islamist stronghold of Afgoye

ABOUT US
Suspicion resides in two regions of the brain

Personality genes may help account for longevity

Chimpanzees have human-like personalities

Urban landscape's power to hurt or heal




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement