Links for Keyword: Drug Abuse

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Criminalising drugs is harming medical research

by Jon White David Nutt, former adviser to the UK government, says the ban on drugs like ecstasy is hampering neuroscience How do the drug laws in most countries affect scientific research? One of the things I find very disturbing about the current approach to drugs, which is simply prohibition without necessarily any full understanding of harms, is that we lose sight of the fact that these drugs may well give us insights into areas of science that need to be explored and may give us new opportunities for treatment. In what way? Almost all the drugs of interest in terms of understanding brain phenomena such as consciousness, perception, mood and psychosis are illegal. And so there is almost no work done in this field. How bad is the impact? The effects these laws have had on research is greater than those caused by the US government hindering stem cell research. No one has done an imaging neuroscience study of smoking cannabis. I can show you 150 papers telling you how the brain reacts to an angry face, but I can't show you a single paper that tells you what cannabis does. Any examples of missed opportunities? There were six trials of LSD as a treatment for alcoholism, the last one in 1965. The evidence is it's as good as anything we've got, maybe better. But no one is using it for this. © Copyright Reed Business Information Ltd

Related chapters from BP6e: Chapter 4: The Chemical Bases of Behavior: Neurotransmitters and Neuropharmacology
Related chapters from MM:Chapter 4: The Chemistry of Behavior: Neurotransmitters and Neuropharmacology
Link ID: 16901 - Posted: 06.12.2012

Risky Rise of the Good-Grade Pill

By ALAN SCHWARZ He steered into the high school parking lot, clicked off the ignition and scanned the scraps of his recent weeks. Crinkled chip bags on the dashboard. Soda cups at his feet. And on the passenger seat, a rumpled SAT practice book whose owner had been told since fourth grade he was headed to the Ivy League. Pencils up in 20 minutes. The boy exhaled. Before opening the car door, he recalled recently, he twisted open a capsule of orange powder and arranged it in a neat line on the armrest. He leaned over, closed one nostril and snorted it. Throughout the parking lot, he said, eight of his friends did the same thing. The drug was not cocaine or heroin, but Adderall, an amphetamine prescribed for attention deficit hyperactivity disorder that the boy said he and his friends routinely shared to study late into the night, focus during tests and ultimately get the grades worthy of their prestigious high school in an affluent suburb of New York City. The drug did more than just jolt them awake for the 8 a.m. SAT; it gave them a tunnel focus tailor-made for the marathon of tests long known to make or break college applications. “Everyone in school either has a prescription or has a friend who does,” the boy said. © 2012 The New York Times Company

Defining alcohol abuse sparks debate

Removing alcohol abuse from psychiatry's diagnostic bible is drawing fire. Proposed changes for the DSM-5 include merging alcohol dependence and abuse categories into a single diagnosis: substance abuse disorder. Doctors, insurers, scientists, and those in the legal system turn to the manual when drawing the line between what psychiatrists consider normal and not normal. June's issue of the Journal of Studies of Alcohol and Drugs includes a critique of the changes and a defence. "Our goal was to try to make the criteria easier for the usual clinician to use, and so we're no longer asking them to remember one criteria set for abuse and a separate set for dependence," said Dr. Marc Schuckit, the journal's editor. While Schuckit served on the DSM-5's substance use committee, he said the views in the editorial reflect his own opinions and experience with the group's consensus approach. Abolishing the abuse category was done because there wasn't enough data to support an inbetween state, Dr. Griffith Edwards of the National Addiction Centre in London, UK said in a critical letter appearing in the same issue. "This decision goes against clinical experience, which suggests that people can develop destructive and disruptive drinking behaviour without clinical symptoms of dependence," Edwards wrote. © CBC 2012

Health risks of cannabis 'underestimated', experts warn

Experts are warning that the public dangerously underestimates the health risks linked to smoking cannabis. The British Lung Foundation carried out a survey of 1,000 adults and found a third wrongly believed cannabis did not harm health. And 88% incorrectly thought tobacco cigarettes were more harmful than cannabis ones - when the risk of lung cancer is actually 20 times higher. The BLF said the lack of awareness was "alarming". Latest figures show that 30% of 16-59 year-olds in England and Wales have used cannabis in their lifetimes. A new report from the BLF says there are established scientific links between smoking cannabis and tuberculosis, acute bronchitis and lung cancer. Cannabis has also been shown to increase chances of developing mental health problems such as schizophrenia. Part of the reason for this, say the experts, is that people smoking cannabis take deeper puffs and hold them for longer than when smoking tobacco cigarettes. This means that someone smoking a cannabis cigarette inhales four times as much tar as from a tobacco cigarette, and five times as much carbon monoxide, the BLF says. Its survey found that young people are particularly unaware of the risks. BBC © 2012

Odds of quitting smoking affected by genetics

Genetics can help determine whether a person is likely to quit smoking on his or her own or need medication to improve the chances of success, according to research published in today's American Journal of Psychiatry. Researchers say the study moves health care providers a step closer to one day providing more individualized treatment plans to help patients quit smoking. The study was supported by multiple components of the National Institutes of Health, including the National Institute on Drug Abuse (NIDA), the National Human Genome Research Institute, the National Cancer Institute, and the Clinical and Translational Science Awards program, administered by the National Center for Advancing Translational Sciences. “This study builds on our knowledge of genetic vulnerability to nicotine dependence, and will help us tailor smoking cessation strategies accordingly,” said NIDA Director Nora D. Volkow, M.D. “It also highlights the potential value of genetic screening in helping to identify individuals early on and reduce their risk for tobacco addiction and its related negative health consequences.” Researchers focused on specific variations in a cluster of nicotinic receptor genes, CHRNA5-CHRNA3-CHRNB4, which prior studies have shown contribute to nicotine dependence and heavy smoking. Using data obtained from a previous study supported by the National Heart Lung and Blood Institute, researchers showed that individuals carrying the high-risk form of this gene cluster reported a 2-year delay in the median quit age compared to those with the low-risk genes. This delay was attributable to a pattern of heavier smoking among those with the high risk gene cluster.

Drunk birds had one-too-many berries to blame

by Jeff Hecht After overindulging in berries, flocks of cedar waxwings flew drunkenly to their doom. That's the conclusion of a new report in the Journal of Ornithology. Cedar waxwings have evolved to live on a diet that averages 84 per cent fruit. But those evolutionary innovations backfired on several occasions between 2005 and 2007 when flocks of them died after crashing into windows and fences in broad daylight in the Los Angeles area. Residents puzzled by the deaths sent the bodies to the California Animal Health and Food Safety Laboratory in San Bernardino. Necropsies performed by Hailu Kinde and colleagues at the lab showed the birds had been healthy when they gorged on berries from the Brazilian pepper tree, then died from ruptured livers or other traumas caused by the collisions. Flocking hell Cedar waxwings have the most fruit-rich diet of all North American birds, and dining on overripe berries can leave them visibly tipsy. Their short intestines can process large volumes of fruit, and their large livers – about 5 per cent of body mass – can break down toxic ethanol before it causes serious damage. Yet although earlier studies had found isolated birds that had died from collisions when flying drunk, no one had seen whole flocks careen to their doom. © Copyright Reed Business Information Ltd.

Related chapters from BP6e: Chapter 4: The Chemical Bases of Behavior: Neurotransmitters and Neuropharmacology; Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:Chapter 4: The Chemistry of Behavior: Neurotransmitters and Neuropharmacology
Link ID: 16846 - Posted: 05.26.2012

Drugs Help Tailor Alcoholism Treatment

By DOUGLAS QUENQUA If alcoholism is a disease, is there hope of finding the cure in a pill? Yes and no. Having mapped the physical changes the brain undergoes with years of habitual drinking, researchers in recent years have discovered a handful of promising — and some say underused — drugs that, combined with therapy, help alcoholics break the cycle of addiction. To those for whom such remedies work, they certainly can feel like a cure. “I felt like I had found something that finally helped me through the cravings,” said Patty Hendricks, 49, who used one such drug, naltrexone, to help control her drinking habit after four failed rehab attempts. “I don’t think I could have gotten sober without it.” The problem is that alcoholics, like cancer patients, are not a homogeneous group. People drink compulsively for any number of reasons, from genetics to anxiety to post-traumatic stress disorder. The pill that helped Ms. Hendricks get sober might do nothing for, say, a veteran who drinks to ward off nightmares. “Just as breast cancer isn’t just one type of breast cancer,” said Dr. Nora D. Volkow, director of the National Institute on Drug Abuse, “alcoholism is heterogeneous as a disorder, so there’s clearly not one drug that is going to work for everybody.” Instead, some addiction experts now envision a future — possibly no more than a decade away — in which treatment for alcoholism mirrors contemporary approaches to depression: Patients will choose from a range of drugs to find the one that best suits them, then couple it with therapy and other tools to achieve long-term recovery. © 2012 The New York Times Company

Coffee gives jolt to life span

By Nathan Seppa It’s the news that coffee addicts have been waiting for: Drinking several cups of coffee every day may help you live longer. A study of more than 400,000 people finds that drinking coffee reduces the risk of death from heart disease, stroke and even infections, researchers report in the May 17 New England Journal of Medicine. Scientists have long puzzled over the notion that a stimulant could provide a health benefit. “There’s been a concern for a long time” that coffee could even be detrimental, says study coauthor Neal Freedman, an epidemiologist at the National Cancer Institute in Bethesda, Md. “Our results might provide some reassurance for long-term coffee drinkers.” Since the study volunteers weren’t randomly assigned to drink coffee or not, the research has the limitations of being observational in nature. But with data from 402,260 participants, the results are “very powerful” and unlikely to be superseded by another coffee study anytime soon, says Roy Ziegelstein, a cardiologist at the Johns Hopkins Bayview Medical Center. “This might be as good as it gets,” he says. Freedman and his colleagues analyzed data provided by men and women who completed a detailed questionnaire that included information about coffee intake as part of a medical study in the mid-1990s. The researchers excluded people who had previously had cancer, heart disease or some other serious illness and recorded the remaining volunteers’ mortality status through 2008 by checking death records. © Society for Science & the Public 2000 - 2012

Do Psychedelics Expand the Mind by Reducing Brain Activity?

By Adam Halberstadt and Mark Geyer What would you see if you could look inside a hallucinating brain? Despite decades of scientific investigation, we still lack a clear understanding of how hallucinogenic drugs such as LSD (lysergic acid diethylamide), mescaline, and psilocybin (the main active ingredient in magic mushrooms) work in the brain. Modern science has demonstrated that hallucinogens activate receptors for serotonin, one of the brain’s key chemical messengers. Specifically, of the 15 different serotonin receptors, the 2A subtype (5-HT2A), seems to be the one that produces profound alterations of thought and perception. It is uncertain, however, why activation of the 5-HT2A receptor by hallucinogens produces psychedelic effects, but many scientists believe that the effects are linked to increases in brain activity. Although it is not known why this activation would lead to profound alterations of consciousness, one speculation is that an increase in the spontaneous firing of certain types of brain cells leads to altered sensory and perceptual processing, uncontrolled memory retrieval, and the projection of mental “noise” into the mind’s eye. The English author Aldous Huxley believed that the brain acts as a “reducing valve” that constrains conscious awareness, with mescaline and other hallucinogens inducing psychedelic effects by inhibiting this filtering mechanism. Huxley based this explanation entirely on his personal experiences with mescaline, which was given to him by Humphrey Osmond, the psychiatrist who coined the term psychedelic. Even though Huxley proposed this idea in 1954, decades before the advent of modern brain science, it turns out that he may have been correct. Although the prevailing view has been that hallucinogens work by activating the brain, rather than by inhibiting it as Huxley proposed, the results of a recent imaging study are challenging these conventional explanations. © 2012 Scientific American,

Addiction Diagnoses May Rise Under Guideline Changes

By IAN URBINA WASHINGTON — In what could prove to be one of their most far-reaching decisions, psychiatrists and other specialists who are rewriting the manual that serves as the nation’s arbiter of mental illness have agreed to revise the definition of addiction, which could result in millions more people being diagnosed as addicts and pose huge consequences for health insurers and taxpayers. The revision to the manual, known as the Diagnostic and Statistical Manual of Mental Disorders, or D.S.M., would expand the list of recognized symptoms for drug and alcohol addiction, while also reducing the number of symptoms required for a diagnosis, according to proposed changes posted on the Web site of the American Psychiatric Association, which produces the book. In addition, the manual for the first time would include gambling as an addiction, and it might introduce a catchall category — “behavioral addiction — not otherwise specified” — that some public health experts warn would be too readily used by doctors, despite a dearth of research, to diagnose addictions to shopping, sex, using the Internet or playing video games. Part medical guidebook, part legal reference, the manual has long been embraced by government and industry. It dictates whether insurers, including Medicare and Medicaid, will pay for treatment, and whether schools will expand financing for certain special-education services. Courts use it to assess whether a criminal defendant is mentally impaired, and pharmaceutical companies rely on it to guide their research. © 2012 The New York Times Company

This Is Your Brain on Drugs

By Christof Koch In the 1954 foundational text of the Age of Aquarius, The Doors of Perception, Aldous Huxley describes his encounters with mescaline, a psychoactive substance derived from the peyote cactus and traditionally used by Native Americans for religious purposes. Huxley’s experiences include profound changes in the visual world, colors that induce sound, the telescoping of time and space, the loss of the notion of self, and feelings of oneness, peacefulness and bliss more commonly associated with religious visions or an exultant state: “A moment later a clump of Red Hot Pokers, in full bloom, had exploded into my field of vision. So passionately alive that they seemed to be standing on the very brink of utterance, the flowers strained upwards into the blue.... I looked down at the leaves and discovered a cavernous intricacy of the most delicate green lights and shadows, pulsing with undecipherable mystery.” Yet remarkably these enhanced percepts are not grounded in larger but in reduced brain activity, as a recent experiment reports. More on that in a moment. Mescaline, together with psilocybin, another natural psychoactive compound produced by “magic” mushrooms, and lysergic acid diethylamide (LSD or, simply, acid), a potent synthetic psychedelic drug, became widely popular in the 1960s counterculture. The striking similarities between the reports of LSD users and symptoms of acute psychosis led researchers to postulate that serotonin, a chemical-signaling compound or neurotransmitter released by certain groups of neurons in the brain stem, helped to mediate both types of experiences. Indeed, it is now quite certain that the characteristic subjective and behavioral effects of psychedelics are initiated via stimulation of serotonin 2A receptors (known as 5-HT2A) on cortical neurons. © 2012 Scientific American

Drug withdrawal rate triples in newborns

The number of babies born in the United States with signs of drug withdrawal has tripled in a decade because more pregnant women are using narcotics, according to a new study. The rate of infants born with withdrawal symptoms reached about one every hour in 2009, researchers report in this week’s issue of the Journal of the American Medical Association. Aileen Dannelley and her baby, Savannah, of Oak Lawn, Ill., both fought addiction to prescription painkillers, an increasing issue in the U.S. Aileen Dannelley and her baby, Savannah, of Oak Lawn, Ill., both fought addiction to prescription painkillers, an increasing issue in the U.S. (Dannelley Family/Associated Press) "What we found was that from 2000 to 2009, the number of babies having drug withdrawal increased by three times," said the study’s lead author, Dr. Stephen Patrick of the University of Michigan's division of neonatal-perinatal medicine in Ann Arbor. For the study, Patrick and his co-authors reviewed hospital billing data from across the U.S. They looked at how many women were using opiates at the time of delivery as well as whether the newborns showed drug withdrawal symptoms. © CBC 2012

The Evolution of the Runner’s High

By GRETCHEN REYNOLDS Ferrets don’t often figure in studies of exercise, perhaps because they don’t exercise much. They slink like fog through tunnels, sprint briefly over open ground and spend much of their time sleeping. They are, in biological terms, what’s called a noncursorial species, meaning that they are reluctant and lousy distance runners. Which is why they were ideal subjects for a new experiment conducted at the University of Arizona in Tucson looking at whether humans and other species evolved to like running. Many anthropologists and distance runners believe that running guided the evolution of early humans. We ran in search of dinner and away from predators. But running is costly, metabolically. It incinerates energy. It can also cause injury. A twisted ankle would have removed your typical early human from the gene pool. So why did our ancestors continue to run over the millennia “and not evolve other strategies for survival?” asks David A. Raichlen, a professor of anthropology at the University of Arizona, who led the study, which was published in The Journal of Experimental Biology. “We wondered if natural selection might have used neurobiological mechanisms to encourage exercise activity,” he continues. Specifically, he and his colleagues became interested in the evolutionary role of the endocannabinoid system. As the name suggests, endocannabinoids are chemicals that, like cannabis in marijuana, alter and lighten moods. But the body produces endocannabinoids naturally. In other studies, endocannabinoid levels have been shown to increase after prolonged running and cycling, leading many scientists to conclude that endocannabinoids help to create runner’s high. Copyright 2012 The New York Times Company

Related chapters from BP6e: Chapter 4: The Chemical Bases of Behavior: Neurotransmitters and Neuropharmacology; Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 4: The Chemistry of Behavior: Neurotransmitters and Neuropharmacology; Chapter 5: The Sensorimotor System
Link ID: 16712 - Posted: 04.26.2012

Cocaine May Age the Brain

by Elizabeth Norton Add this to the list of reasons not to take cocaine: Chronic use of the drug may speed up the aging process. According to a new imaging study, cocaine abusers in their 30s and 40s show brain changes more commonly seen in people over 60. The finding also calls attention to the special medical needs of older drug users—a group that, until now, hasn't garnered much notice. "Drug abuse is typically considered a young people's problem," says behavioral neuroscientist Karen Ersche at the University of Cambridge in the United Kingdom. But baby boomers, many of whom began experimenting with drugs when they were young, are getting older. And according to Ersche's research, some of them may be getting older faster. Studies show that middle-aged drug abusers often have problems more commonly seen in the elderly, such as memory loss, increased susceptibility to infection, and higher rates of cardiovascular disease. Rates of premature death among drug abusers are up to eight times higher than in the general population, according to some estimates. People addicted to cocaine also perform poorly on tasks that involve an area of the brain called the prefrontal cortex, such as memory, attention, and reaction time. Because elderly people can have similar mental impairments, Ersche wondered if chronic exposure to cocaine accelerates these changes in the brain. To investigate, she and colleagues studied 120 people between the ages of 18 and 50. About half met criteria for cocaine addiction: They had used cocaine for an average of 10 years and had the drug in their systems on the day of the scan, according to urine tests. © 2010 American Association for the Advancement of Science.

Experimental Biology Blogging: Drug punishers to reduce drug reinforcement

By Scicurious Drug addiction is a vicious cycle, but the original high is not the problem. What is the problem are the changes in our brains and behavior that drive us to seek the next high, and the next. The relationship between drug-taking and the resulting high is what behavioral pharmacologists refer to as “reinforcement”. And if we are able to alter the reinforcing value of a drug, how much we desire to get that next hit, we might be able to help addicts overcome their addictions. There are various methods that pharmacologists have tried over the years to decrease the reinforcing value of drugs in experimental situations. You can accompany a drug with an antagonist that blocks the drug effects, like combining heroin with naltrexone so that an addict attempting to take the drug cannot get high. This blocks the high, but people can always try to take more drug to overcome the antagonist effects. Another method is using long-acting, low dose drugs as replacements, such as methadone, to block the withdrawal of from drugs such as heroin or morphine. But again, people can always take more drug on top of it. Finally, there is the idea of using drug punishment. In this paradigm, you use a drug that induces nasty effects, like nausea or pain, in conjunction with the abused drug, to make people stop taking the drug. We call this paradigm a “drug punisher”. This is the idea that Kevin Freeman, Brian McMaster, and William Woolverton, in their presentation at the Experimental Biology 2012 Behavioral Pharmacology meeting, have decided to work with in cocaine using rhesus monkeys. They trained the monkeys to self-administer cocaine by pressing a lever, which delivered a shot of cocaine into the monkey’s veins. © 2012 Scientific American

How Psychedelic Drugs Can Help Patients Face Death

By LAUREN SLATER Pam Sakuda was 55 when she found out she was dying. Shortly after having a tumor removed from her colon, she heard the doctor’s dreaded words: Stage 4; metastatic. Sakuda was given 6 to 14 months to live. Determined to slow her disease’s insidious course, she ran several miles every day, even during her grueling treatment regimens. By nature upbeat, articulate and dignified, Sakuda — who died in November 2006, outlasting everyone’s expectations by living for four years — was alarmed when anxiety and depression came to claim her after she passed the 14-month mark, her days darkening as she grew closer to her biological demise. Norbert Litzinger, Sakuda’s husband, explained it this way: “When you pass your own death sentence by, you start to wonder: When? When? It got to the point where we couldn’t make even the most mundane plans, because we didn’t know if Pam would still be alive at that time — a concert, dinner with friends; would she still be here for that?” When came to claim the couple’s life completely, their anxiety building as they waited for the final day. As her fears intensified, Sakuda learned of a study being conducted by Charles Grob, a psychiatrist and researcher at Harbor-U.C.L.A. Medical Center who was administering psilocybin — an active component of magic mushrooms — to end-stage cancer patients to see if it could reduce their fear of death. Twenty-two months before she died, Sakuda became one of Grob’s 12 subjects. When the research was completed in 2008 — (and published in the Archives of General Psychiatry last year) — the results showed that administering psilocybin to terminally ill subjects could be done safely while reducing the subjects’ anxiety and depression about their impending deaths. © 2012 The New York Times Company

Why Booze Makes Some People Belligerent

By Harvey Black Some people are friendly drunks, whereas others are hostile, potentially endangering themselves and others. The difference may lie in their ability to foresee the consequences of their actions, according to a recent study in the online Journal of Experimental Social Psychology. Brad Bushman, a psychologist at Ohio State University, and his colleagues asked nearly 500 volunteers to play a simple game. The subjects, an even mix of women and men, believed they were competing against an opponent to press a button as quickly as possible. In reality, they were simply using a computer program that randomly decided if they had won or lost. When they lost, they received a shock. When the “opponent” lost, the participant gave the shock and chose how long and intense it should be. Before playing, the participants completed a survey designed to measure their general concern for the future consequences of their actions. Half the participants then received enough alcohol mixed with orange juice to make them legally drunk, and the other half received a drink with a very tiny amount of alcohol in it. Subjects who expressed little interest in consequences were more likely to administer longer, more intense shocks. In the sober group, they were slightly more aggressive than people who cared about consequences. When drunk, however, their belligerence was off the charts. “They are by far the most aggressive people in the study,” Bushman says. © 2012 Scientific American

Related chapters from BP6e: Chapter 15: Emotions, Aggression, and Stress; Chapter 4: The Chemical Bases of Behavior: Neurotransmitters and Neuropharmacology
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress; Chapter 4: The Chemistry of Behavior: Neurotransmitters and Neuropharmacology
Link ID: 16686 - Posted: 04.21.2012

Small terms make a big difference: how the NY Times misinterpreted a new cocaine study

Dr. Becca, author of the blog ‘Fumbling Toward Tenure’. Last week, the New York Times’ “Well” section ran a piece titled, “How Exercise Can Prime the Brain for Addiction.” Scary, right? One minute you’re cruising along on the treadmill, and next thing you know, you’re ADDICTED TO COCAINE. Hovering over the web page tab header, however, reveals what may have been the original title—the more qualified, but less provocative “How Exercise May Make Addictions Better, or Worse.” Ironically, it’s the cutting-room-floor version of the title that more accurately (but only marginally so) reflects the findings of Mustroph et al (2012), an Illinois-based research group who studied the influence of exercise on the learning processes associated with drug use. In a nutshell, the researchers showed that the timing of exercise and drug exposure mattered: animals that exercised after getting a few injections of cocaine had an easier time “letting go” of their drug-associated cues than animals that exercised before cocaine exposure did. What Mustroph et al were not studying, though, was addiction—and this is only the beginning of where NYT writer Gretchen Reynolds does a disappointingly poor job of science reporting. This paper is about learning. With every experience we have, we learn something about the circumstances in which that experience occurred, and experience with drugs is no different. If you always do drugs in a certain room of your house, or at one particular club, you’re going to start associating those places with the drug, and, in all likelihood, with the way the drug makes you feel. You might even enjoy hanging out in those places when you’re not using the drug, because of the positive associations you’ve formed. © 2012 Scientific American

Related chapters from BP6e: Chapter 4: The Chemical Bases of Behavior: Neurotransmitters and Neuropharmacology; Chapter 17: Learning and Memory
Related chapters from MM:Chapter 4: The Chemistry of Behavior: Neurotransmitters and Neuropharmacology; Chapter 13: Memory, Learning, and Development
Link ID: 16668 - Posted: 04.19.2012

Memory 'trick' relieves drug cravings

Mo Costandi Researchers have come up with a way to help prevent recovering drug addicts from relapsing — without using other pharmaceuticals to help. The approach involves modifying addicts' behaviour by weakening their memory of drug taking, which relieves their cravings and might help to prevent relapse. Addicts tend to associate a drug's effects with drug-taking equipment and a certain environment, which can make them vulnerable to relapse if they encounter those conditions. The technique, studied by Lin Lu of the National Institute of Drug Dependence at Peking University in Beijing and his colleagues, aims to break that link by briefly reactivating the memory of drug taking and following it with an 'extinction session' of repeated exposure to the same memory cues. The short reminder of drug-taking seems to take the memory out of storage and make it easier to overwrite. Existing therapies try to help addicts to unlearn their habit by, for example, showing them videos of people injecting, and having them handle syringes while not under the influence of the drug. This reduces cravings in the clinic, but not when addicts return to their usual surroundings. Other approaches tested in rats involved using memory-blocking drugs to change memories of past drug use, but these are not approved for use in humans. To boost the technique's effectiveness, Lu and his team combined the approach with a process called memory reconsolidation. During reconsolidation, information is retrieved from long-term storage and reactivated to strengthen the memory. After retrieval, however, the information becomes temporarily unstable and thus prone to alteration. Their work is published today in Science1. © 2012 Nature Publishing Group

How Exercise Can Prime the Brain for Addiction

By GRETCHEN REYNOLDS, Columnist Statistically, people who exercise are much less likely than inactive people to abuse drugs or alcohol. But can exercise help curb addictions? Some research shows that exercise may stimulate reward centers in the brain, helping to ease cravings for drugs or other substances. But according to an eye-opening new study of cocaine-addicted mice, dedicated exercise may in some cases make it even harder to break an addiction. The study, conducted by researchers at the Beckman Institute for Advanced Science and Technology at the University of Illinois in Urbana-Champaign, began by dividing male mice into those that had or did not have running wheels in their cages. All of the mice were injected with a chemical that marks newly created brain cells. The animals then sat in their cages or ran at will for 30 days. Afterward, the mice were placed in small multiroom chambers in the lab and introduced to liquid cocaine. They liked it. Researchers frequently use a model known as “conditioned place preference” to study addiction in animals. If a rodent returns to and stubbornly plants itself in a particular place where it has received a drug or other pleasurable experience, then the researchers conclude that the animal has become habituated. It badly wants to repeat the experience that it associates with that place. All of the mice displayed a decided place preference for the spot within their chamber where they received cocaine. They had learned to associate that location with the pleasures of the drug. All of the mice had, essentially, become addicts. © 2012 The New York Times Company

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