(Press-News.org) Contact: David A. Kareken
dkareken@iupui.edu
317-274-7327
Indiana University School of Medicine
Alcoholism: Clinical & Experimental Research
The brain's response to sweets may indicate risk for development of alcoholism
Several human and animal studies have shown a relationship between a preference for highly sweet tastes and alcohol use disorders. Furthermore, the brain mechanisms of sweet-taste responses may share common neural pathways with responses to alcohol and other drugs. A new study using functional magnetic resonance imaging (fMRI) has found that recent drinking is related to the orbitofrontal-region brain response to an intensely sweet stimulus, a brain response that may serve as an important phenotype, or observable characteristic, of alcoholism risk.
Results will be published in the December 2013 issue of Alcoholism: Clinical & Experimental Research and are currently available at Early View.
"It has long-been known that animals bred to prefer alcohol also drink considerably greater quantities of sweetened water than do animals without this selective breeding for alcohol preference," explained David A. Kareken, deputy director of the Indiana Alcohol Research Center, a professor in the department of neurology at Indiana University School of Medicine, and corresponding author for the study. "More recently, it has become clear that animals bred to prefer the artificial sweetener, saccharin, also drink more alcohol. Although the data in humans are somewhat more variable, some studies do show that alcoholics, or even non-alcoholics with a family history of alcoholism, have a preference for unusually sweet tastes. Thus, while the precise reasons remain unclear, there does seem to be significant evidence suggesting some link between the rewarding properties of both sweet tastes and alcohol."
Kareken added that this is the first study to examine the extent to which regions of the brain's reward system, as they respond to an intensely sweet taste, are related to human drinking patterns.
Kareken and his colleagues recruited 16 (12 males, 4 females) right-handed, non-treatment seeking, healthy volunteers with a mean age of 26 years from the community. All participants underwent a taste test using a range of sucrose concentrations, and their blood oxygen dependent (BOLD) activation was measured during an fMRI scan while receiving small squirts of either water or an intensely sweet mixture of sugar in water. All were asked about their drinking patterns.
"Our study was designed to determine which brain areas responded to sweet taste – as compared to plain water – and the extent to which these brain responses were related to subjects' binge-drinking patterns, the number of alcoholic drinks subjects consumed per day when drinking," explained Kareken.
"In addition to 'activating' the brain's gustatory or taste circuits, the sugared water also activated key elements of what neuroscientists consider to be part of the brain's reward system, including the ventral striatum, amygdala, and parts of the orbitofrontal cortex – the inferior frontal lobe surface just above the eyes – that respond to ingested rewards," Kareken said. "We refer to these as 'primary' rewards, being distinct from secondary rewards, like money, which can be used to obtain primary rewards."
What the researchers found was that the response to this intensely sweet taste in the left orbitofrontal area correlated significantly with subjects' drinking patterns.
"Specifically, the trend was such that those who drank more alcohol on drinking days had stronger left orbitofrontal responses to the intensely sweet water," said Kareken. "Subjects' subjectively rated liking of the sweetened water also contributed to this relationship, so that both the brain response itself, as well as liking of the sugared water, collectively correlated with drinking behavior."
While previous human and animal research has noted this association between preferences for both sweet tastes and alcohol intoxication, Kareken believes that this is the first study to examine the human brain mechanism behind this association.
"While much more research needs to be done to truly understand the commonalities between sweet-liking and alcoholism, and while alcoholism itself is likely the product of several mechanisms, our findings may implicate a particular brain region that is more generally involved in coding for the value of 'primary' rewards such as pleasures," he said. "In a more practical sense, the findings are compelling evidence that the brain response to an intensely sweet taste may be used in future research to test for differences in the reward circuits of those at risk for alcoholism. This may be particularly useful since alcohol itself is not an easy drug to work with in this kind of human imaging, and since alcohol exposure is not ethically appropriate for use in all at-risk subjects, or in subjects trying to abstain from drinking."
###
Alcoholism: Clinical & Experimental Research (ACER) is the official journal of the Research Society on Alcoholism and the International Society for Biomedical Research on Alcoholism. Co-authors of the ACER paper, "A Preliminary Study of the Human Brain Response to Oral Sucrose and its Association with Recent Drinking," were: Mario Dzemidzic of the Departments of Neurology and Radiology at Indiana University School of Medicine; and Brandon G. Oberlin and William J.A. Eiler II of the Department of Neurology at Indiana University School of Medicine. The study was funded by the Elvin S. Eyster Fund in Neurology, and the National Institutes of Health. This release is supported by the Addiction Technology Transfer Center Network at http://www.ATTCnetwork.org.
The brain's response to sweets may indicate risk for development of alcoholism
2013-07-11
ELSE PRESS RELEASES FROM THIS DATE:
Kids' allergies may correlate with omega-3, omega-6 lipid levels in cord blood
2013-07-11
Children with high proportions of poly-unsaturated fatty acids (PUFA) in cord blood at birth are more likely to develop respiratory and skin allergies in their early teens, according to research published July 10 in the open access journal PLOS ONE by Malin Barman and colleagues from the Chalmers University of Technology, Sweden.
The researchers followed nearly 800 children born in 1996-97 for diagnosis of allergies at age 13, and studied a subset of 44 who were diagnosed with respiratory allergies, 37 with chronic skin rashes and 48 who did not suffer allergies. Cord ...
Same beat set to different tunes changes walkers' pace
2013-07-11
Personal tastes in music have little to do with how we keep time to a tune while walking, according to research published July 10 by Marc Leman and colleagues from Ghent University, Belgium in the open access journal PLOS ONE.
Most people synchronize their steps to the beat of their tunes when they listen to music on a walk. In the current study, researchers found that even when excerpts of music had identical tempo and beat, other acoustic features influenced walkers' stride and speed.
Participants in the study heard samples of 52 different types of music that all ...
Typhoid's lethal secret revealed
2013-07-11
Typhoid fever is one of the oldest documented diseases known to have afflicted mankind but what makes it so lethal has remained a mystery for centuries. In a study appearing online July 10 in the journal Nature, Yale researchers offer an explanation of how the devastating disease marked by delirium and stupor still kills 200,000 people every year - and also suggests the basis of a future vaccine.
The culprit appears to be a powerful toxin possessed by Salmonella typhi, the bacterium that causes typhoid fever. Yale scientists for the first time describe the structure of ...
Efficiency in the forest
2013-07-11
Spurred by increasing levels of atmospheric carbon dioxide, forests over the last two decades have become dramatically more efficient in how they use water, a Harvard study has found.
Studies have long predicted that plants would begin to use water more efficiently as atmospheric carbon dioxide levels rose. A research team led by Research Associate Trevor Keenan and Assistant Professor of Organismic and Evolutionary Biology Andrew Richardson, however, has found that forests across the globe are becoming more efficient than expected.
Using data collected from forests ...
Study puts troubling traits of H7N9 avian flu virus on display
2013-07-11
MADISON, Wis. — The emerging H7N9 avian influenza virus responsible for at least 37 deaths in China has qualities that could potentially spark a global outbreak of flu, according to a new study published today (July 10, 2013) in the journal Nature.
An international team led by Yoshihiro Kawaoka of the University of Wisconsin-Madison and the University of Tokyo conducted a comprehensive analysis of two of the first human isolates of the virus from patients in China. Their efforts revealed the H7N9 virus's ability to infect and replicate in several species of mammals, including ...
Mammals can 'choose' sex of offspring, Stanford-led study finds
2013-07-11
STANFORD, Calif. — A new study led by a researcher at the Stanford University School of Medicine shows that mammalian species can "choose" the sex of their offspring in order to beat the odds and produce extra grandchildren.
In analyzing 90 years of breeding records from the San Diego Zoo, the researchers were able to prove for the first time what has been a fundamental theory of evolutionary biology: that mammals rely on some unknown physiologic mechanism to manipulate the sex ratios of their offspring as part of a highly adaptive evolutionary strategy.
"This is one ...
NHS facing a 'deepening financial crisis' says Head of Health Policy at the BMA
2013-07-11
Chancellor George Osborne has announced an increase in health spending of 1.9% for 2015/16, but taking inflation into account the true figure will be just 0.1%. And although politicians are promising to protect and increase the health budget every year, the latest Comprehensive Spending Review shows that the reality to be quite different.
According to Ford, the NHS will have had to find £20 billion in efficiency savings by then and build even more savings on top. With demand for services rising by 4% per year, the NHS will have to generate further savings of £4.25bn to ...
Lack of cultural understanding makes forced marriage victims wary of social services, study finds
2013-07-11
Victims of forced marriage and honour violence in the UK are hesitant to seek professional help because they are worried social workers will not understand their cultural differences, according to new research presented today at Royal Holloway University.
Researchers at Royal Holloway have called for social workers to receive mandatory training on sensitive issues surrounding different cultures and religious backgrounds, so that they understand that normal practices, such as involving family members, may not be the best solution in forced marriage cases.
The study, ...
Researchers set out path for global warming reversal
2013-07-11
Bioenergy with carbon capture and storage (BECCS) can reverse the global warming trend and push temperatures back below the global target of 2°C above pre-industrial levels, even if current policies fail and we initially overshoot this target.
This is according to a new study, published today, 11 July, in IOP Publishing's journal Environmental Research Letters, which shows that ambitious temperature targets can be exceeded then reclaimed by implementing BECCS around mid-century.
The researchers, from Chalmers University of Technology in Sweden, show that if BECCS is ...
Do antibiotics in animal feed pose a serious risk to human health?
2013-07-11
David Wallinga from Keep Antibiotcs Working: the Campaign to End Antibiotic Overuse in Animal Agriculture, believes that physicians and policymakers have "overlooked the critical role played by the ongoing overuse of antibiotics in livestock and poultry."
He understands the interest in creating a pipeline of new antibiotics, but says overall reductions in antibiotic use "should come first."
He points to data showing that, in 2009-11, 72% of all US sales of antimicrobials comprised those routinely added to water or animal feed.
These, he says, are "additives in feed ...