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:5/24/2016)... ... ... The Dream Builders Project, a 501(c)3 nonprofit organization based in Los Angeles, ... Mexico on Saturday, May 21st. The volunteers took the children out for the day ... 15 volunteers traveled from Los Angeles to Tijuana, Mexico for the day in the ...
(Date:5/24/2016)... ... 2016 , ... Global Lyme Alliance (GLA), a leading nonprofit ... has named Scott Santarella as its new CEO. , Santarella is former ... San Francisco, where he successfully helped to grow the organization from a regional ...
(Date:5/24/2016)... ... ... PhysicianOne Urgent Care, advocators in helping their patients lead the healthiest lives possible, updates ... spring. , The official tick season kicks off in May across the states ... themselves to their prey while they feed off their blood. Like other similar biting ...
(Date:5/24/2016)... ... May 24, 2016 , ... Applications ... multiplex immunoassays are widely used for cell and protein analysis. Keeping updated on ... quality and efficiency in these areas. , LabRoots introduces a new complementary ...
(Date:5/23/2016)... ... May 23, 2016 , ... On the occasion of his 25th Anniversary of ... weight loss process: , New patients have a consultation and evaluation (done by Dr. ... evaluated. , Body Composition Analysis, There are 15 things that each patient gets checked ...
Breaking Medicine News(10 mins):
(Date:5/23/2016)... -- Global Paclitaxel Market 2016 Industry Research ... and the Paclitaxel analysis in this study is supported ... its players. This is the latest Paclitaxel ... current state of the industry while providing a basic ... industry chain structure. The Paclitaxel market analysis is provided ...
(Date:5/23/2016)... , May 23, 2016 The World Health ... PrePex device to include adolescents aged 13 years, and ... can be offered for adult and adolescent males in the ... . PrePex was the first male circumcision device to ... MedTech,s CEO, Eddy Horowitz said: " The ...
(Date:5/23/2016)... May 23, 2016   Purdue Pharma L.P. ... an agreement with Egalet Corporation and Acura Pharmaceuticals, ... part of the agreement the companies will exchange ... all three companies to develop and sell several ... "This agreement reflects the commitment of Purdue Pharma ...
Breaking Medicine Technology: