Navigation Links
Dopamine release in human brain tracked at microsecond timescale reveals decision-making
Date:10/28/2011

Roanoke, Va. A research team led by investigators at the Virginia Tech Carilion Research Institute has demonstrated the first rapid measurements of dopamine release in a human brain and provided preliminary evidence that the neurotransmitter can be tracked in its movement between brain cells while a subject expresses decision-making behavior.

"In an experiment where we measured dopamine release while a subject made investment decisions in a stock market trading game, we showed that dopamine tracks changes in the value of the market," said Read Montague, director of the Human Neuroimaging Laboratory at the Virginia Tech Carilion Research Institute and professor of physics in the College of Science at Virginia Tech.

"A startling discovery was that the dopamine signal appeared to be a very good indicator of the market value and in many instances a good predictor of future market changes," said Kenneth Kishida, a postdoctoral associate with the Human Neuroimaging Laboratory and the lead author on the report. Interestingly, the choice expressed by the subject did not always correspond with the prescient brain chemistry, he said.

The research was published on Aug. 4, 2011, in the Public Library of Science journal, PLoS ONE, in the article "Sub-Second Dopamine Detection in Human Striatum," by Kishida; Stefan G. Sandberg, senior fellow with the Departments of Psychiatry and Behavioral Sciences and Pharmacology, University of Washington, Seattle; Terry Lohrenz, assistant professor in the Department of Neuroscience, Baylor College of Medicine; Dr. Youssef G. Comair, professor and chief, Division of Neurosurgery, American University of Beirut, Lebanon; Ignacio Saez, assistant professor at Virginia Tech Carilion Research Institute; Paul E. M. Phillips, associate professor, Departments of Psychiatry and Behavioral Sciences and Pharmacology, University of Washington, Seattle; and Montague, senior author.

The researchers adapted their sensors to existing technology used for functional mapping of the brain during surgical implantation of deep-brain stimulation devices. "Deep-brain stimulation is typically used in the treatment of Parkinson's disease," said Montague. "Uses for treating other neurological disorders are also being investigated, though, and may open new avenues for the technology we developed."

The researchers applied criteria that employed experimental methodology that is "safe to the patient, compatible with existing neurosurgical apparatus and the operating-room environment, and capable of sub-second detection of physiological dopamine," they state in the article. They modified existing sensor technology to improve signal conductivity, creating a microsensor that shares the electrochemical properties of existing electrodes yet can detect sub-second dopamine release. "Even more important, the new microsensors are biocompatible and can be sterilized without affecting performance, " Kishida added.

The new instrument was demonstrated in a single human subject, a consenting patient with late-stage Parkinson's disease who was undergoing elective surgery for deep-brain stimulation electrode implantation. The new microsensor was placed in the patient's brain and dopamine release was monitored as the patient engaged in a decision-making game. The current value and recent history of a stock market was graphically represented on a laptop monitor. The subject chose the proportion of a portfolio initially valued at $100 to be invested in the stock market. Decisions were submitted by pushing buttons on handheld response devices. Following the submission of each decision, the market was updated. The final portfolio determined the actual payout at the end of the experiment.

The researchers report that they were surprised to observe that "the slope of the dopamine signal over a period five seconds prior to a market price update correlated with subsequent market returns, demonstrating that it is a significant predictor of future market activity."

To test this hypothesis, the researchers constructed a trader model that made decisions based on the fluctuations in the dopamine signal leading up to the market price changes. This decision model invested 100 percent, or all in, when the dopamine slope was positive and 0 percent, or all out, when the slope was negative. The researchers report that, "Over the five markets played, this trader model earned 202 points (a gain of 175 percent), more than two times the amount earned by the subject's expressed behavior. These data demonstrate that the information encoded in the dopamine signal of this patient is potentially useful for economic decision making."

"This exciting preliminary result requires replication, but it immediately sets the imagination in motion," said Kishida. "I often wonder whether there is a feeling associated with these dopamine fluctuations and whether there is any connection with that 'gut feeling' people sometimes ignore."

Writing in the PLoS ONE article, the researchers conclude, "This methodological demonstration opens the door to future investigations utilizing sub-second chemical measurements in the human brain, which should yield important insights into the role of dopamine signaling in human decision-making."


'/>"/>

Contact: Paula Byron
paulabyron@vtc.vt.edu
540-526-2027
Virginia Tech
Source:Eurekalert

Related medicine news :

1. Safety data favor norepinephrine over dopamine for shock
2. Endometrial stem cells restore brain dopamine levels
3. A high-fat diet alters crucial aspects of brain dopamine signaling
4. Non-dopaminergic drug preladenant reduces motor fluctuations in patients with Parkinsons disease
5. Binge eaters dopamine levels spike at sight, smell of food
6. PolicyLink CEO Angela Glover Blackwell Released the Following Statement on First Lady Michelle Obamas Childhood Obesity Initiative
7. Groundbreaking Principal and Contributor on Dr. Oz Show Releases His Latest Book on How We Can Influence the Lives of Children
8. Beat The Odds and Get Back on Track; Revitalizing Fitness Training and Exercise Resolutions With Newly Released, Complimentary Video Series
9. Womens Dermatologic Society Marks 35th Anniversary with Release of Unprecedented Book of Wisdom and Inspiration
10. International Insurance Group, Inc. Releases First Quarter 2010 Newsletters
11. HeartMath Announces the Release of Their New emWave Desktop Software
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/26/2016)... ... June 27, 2016 , ... Quality metrics are proliferating in cancer care, and ... in the eye of the beholder, according to experts who offered insights and commentary ... of Managed Care. For the full issue, click here . , For the ...
(Date:6/26/2016)... ... June 26, 2016 , ... Many women are ... with endometriosis. These women need a treatment plan to not only alleviate symptoms ... can help for preservation of fertility and ultimately achieving a pregnancy. The specialists ...
(Date:6/25/2016)... ... June 25, 2016 , ... First Choice Emergency Room , the largest ... as the Medical Director of its new Mesquite-Samuell Farm facility. , “We are ... Mesquite location,” said Dr. James M. Muzzarelli, Executive Medical Director of First Choice Emergency ...
(Date:6/24/2016)... ... June 24, 2016 , ... A recent article published ... unfamiliar with. The article goes on to state that individuals are now more comfortable ... less common operations such as calf and cheek reduction. The Los Angeles area medical ...
(Date:6/24/2016)... ... June 24, 2016 , ... Global law firm Greenberg Traurig, P.A. announced that ... chosen by their peers for this recognition are considered among the top 2 percent ... special honors as members of this year’s Legal Elite Hall of Fame: Miami ...
Breaking Medicine News(10 mins):
(Date:6/24/2016)... 24, 2016  Arkis BioSciences, a leading innovator ... more durable cerebrospinal fluid treatments, today announced it ... funding is led by Innova Memphis, followed by ... private investors.  Arkis, new financing will accelerate the ... market release of its in-licensed Endexo® technology. ...
(Date:6/23/2016)... DUBLIN , June 23, 2016 ... "Dialysis Devices Global Market - Forecast to 2022" report ... is the treatment method for the patients with kidney failure, ... and excess fluid from the patient,s blood and thus the ... sodium, potassium and chloride in balance. Increasing ...
(Date:6/23/2016)... 23, 2016 Research and Markets ... Market by Type (Organic Chemical (Sugar, Petrochemical, Glycerin), Inorganic ... Coating, Parenteral) - Global Forecast to 2021" report ... The global pharmaceutical excipients market is projected to ... of 6.1% in the forecast period 2016 to 2021. ...
Breaking Medicine Technology: