Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New research offers insights into how genetics are a prime factor in how we learn

02.10.2007
UA psychologist finds genetic links to learning behavior

Michael Frank, an assistant professor of psychology and director of the Laboratory for Neural Computation and Cognition at The University of Arizona, headed a team whose results are reported in the Oct. 1 issue of Early Edition, an online site hosted by the Proceedings of the National Academy of Sciences.

Frank and his colleagues found links to learning behaviors in three separate genes associated with dopamine. Dopamine is a neurotransmitter, a chemical in the brain that is often associated with pleasure, learning and other behaviors. Several neurological disorders, such as Parkinson's disease, are also linked to abnormal levels of dopamine.

Frank's study points to fundamental genetic differences between "positive" and "negative" learners.

... more about:
»Insights »choice »dopamine »individual »outcome

"All three genes affect brain dopamine functioning, but in different ways, and in different parts of the brain" Frank said. "The genes predicted people's ability to learn from both the positive and negative outcomes of their decisions."

Two of the genes - DARPP-32 and DRD2 - predicted learning about the average, long-term probability of rewards and punishments, not unlike your personal preference for why, for example, you might choose steak over salmon.

"When making these kinds of choices, you do not explicitly recall each individual positive and negative outcome of all of your previous such choices. Instead, you often go with your "gut," which may involve a more implicit representation of the probability of rewarding outcomes based on past experience," Frank said.

The DARPP-32 and DRD2 genes control dopamine function in a region of the brain called the striatum, thought to be necessary for this kind of implicit reward learning. A third gene, COMT, did not predict long-term reward or punishment learning, but instead predicted a person's tendencies to change choice strategies after a single instance of negative feedback. Frank said this gene affects dopamine function in the prefrontal cortex of the brain, the area associated with conscious processing and working memory. This would be akin to switching from steak to salmon upon remembering your last experience with overdone steak.

The overall research program was designed to test a computer model that simulates the key roles of dopamine in reinforcement learning in different parts of the brain, as motivated by a body of biological research.

"The reason we looked at these three individual genes in the first place, out of a huge number of possible genes, is that we have a computer model that examines how dopamine mediates these kinds of reinforcement processes in the striatum and prefrontal cortex," Frank said. "The model makes specific predictions on how subtle changes in different aspects of dopamine function can affect behavior, and one way to get at this question is to test individual genes."

Among the evidence incorporated in the model and motivating the genetic study is research showing that bursts of dopamine production follow in the wake of unexpected rewards. Conversely, dopamine production declines when rewards are expected but not received.

To test their hypothesis, the researchers collected DNA from 69 healthy individuals who were asked to perform a computerized learning program. The volunteers were asked to pick one of two Japanese characters that appeared on a screen and were "rewarded" for a "correct" response, and "punished" for an "incorrect" one.

Frank said more research is needed to confirm that genetic effects are accompanied by brain-related changes in behavior. But, he said, the research offers insights into the genetic basis for learning differences and insights into improving human cognition and learning, both normal and abnormal.

"Understanding how dopaminergic variations affects learning and decision-making processes may have substantial implications for patient populations, such as (those with) Parkinson's disease, attention-deficit hyperactivity disorder (ADHD) and schizophrenia," Frank said. "The genetics might also help us identify individuals who might gain from different types of learning environments in the classroom."

Michael Frank's home page: http://www.u.arizona.edu/~mfrank/

Contact: 520-626-4787, mfrank@u.arizona.edu

Jeff Harrison | University of Arizona
Further information:
http://www.u.arizona.edu/~mfrank/
http://www.arizona.edu

Further reports about: Insights choice dopamine individual outcome

More articles from Life Sciences:

nachricht Water forms 'spine of hydration' around DNA, group finds
26.05.2017 | Cornell University

nachricht How herpesviruses win the footrace against the immune system
26.05.2017 | Helmholtz-Zentrum für Infektionsforschung

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can the immune system be boosted against Staphylococcus aureus by delivery of messenger RNA?

Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.

Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

How herpesviruses win the footrace against the immune system

26.05.2017 | Life Sciences

Water forms 'spine of hydration' around DNA, group finds

26.05.2017 | Life Sciences

First Juno science results supported by University of Leicester's Jupiter 'forecast'

26.05.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>