Risk-taking Rats May Help Advance Treatments For Gambling Disorders

At first glance, research on lab rats who “gamble” might seem either fodder for jokes or irrelevant to the search for solutions for gambling disorders; however, recently published findings of an NCRG-funded investigation at the University of British Columbia demonstrates that such research represents, as Dr. Marc Potenza of Yale University observed, a “significant step forward” that could eventually lead to new treatments for pathological gambling.

The article, “Serotonergic and Dopaminergic Modulation of Gambling Behavior as Assessed Using a Novel Rat Gambling Task,”1was published last month in Neuropsychopharmacology, the fifth-most cited psychiatry journal in the world. The authors reported that rats were able to successfully learn to “play the odds” in a gambling task, modeling human gambling behavior. According to theVancouver Sun, Dr. Catharine Winstanley, one of the study’s authors, called the study “an important first step in offering clues into what neurotransmitters or what brain chemicals are involved in regulating gambling behavior.” In 2006, Winstanleyreceived a New Investigator Grantof $57,500 from the National Center for Responsible Gaming (NCRG), through the Institute for Research on Pathological Gambling and Related Disorders (now the Institute for Research on Gambling Disorders), to help support this investigation.

During the task, the rats were able to choose from four options that differed in the probability and magnitude of food rewards and timeouts (i.e., penalty periods during which no food would be dispensed). High-stake options offered more sugar pellets, but choosing the high-stakes options also was more likely to trigger longer timeouts. According to the study, rats learned how to be “successful” gamblers, selecting the option with the optimum level of risk and reward to maximize their sugar pellet profits over time.

The study also found the rats’ decision-making became significantly impaired in the gambling task when they were treated with drugs that affected the levels of dopamine and serotonin – two neurotransmitters in the brain implicated in impulse control and drug addiction. According to the study, this suggests a role for these neurochemicals in moderating gambling behavior and a potential method of researching new leads for the development of pharmacological treatments for this disorder.

Michael Bozarth, associate professor of psychology at the University of Buffalo, the State University of New York, underscored the significance of animal models for research on gambling: “The development of adequate animal models such as that reported by Winstanley and her coworkers opens the door to studying the impact of direct manipulation of brain function and to exploring the effects of illicit drugs on gambling behavior. These types of studies, not possible in human subjects, are likely to lead to important breakthroughs in our understanding of pathological gambling just like comparable animal models were crucial to a better understanding of drug addiction.”

Dr. Winstanley established the Laboratory of Molecular and Behavioural Neuroscience at the University of British Columbia. She currently is a Michael Smith Early Career Scholar and has received numerous awards for her research, including the 2008 Wyeth Award for outstanding research in Preclinical Psychopharmacology.

References

1Zeeb FD, Robbins TW, Winstanley CA. Serotonergic and Dopaminergic Modulation of Gambling Behavior as Assessed Using a Novel Rat Gambling Task. Neuropsychopharmacology. Jun 17 2009.

Christine Reilly Executive Director, Institute for Research on Gambling DisordersIssues & Insightsanimal modelnew research