Chapter 4. The Chemistry of Behavior: Neurotransmitters and Neuropharmacology

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Ian Sample Science editor Doctors have stumbled on an unlikely source for a drug to ward off brain damage caused by strokes: the venom of one of the deadliest spiders in the world. A bite from an Australian funnel web spider can kill a human in 15 minutes, but a harmless ingredient found in the venom can protect brain cells from being destroyed by a stroke, even when given hours after the event, scientists say. If the compound fares well in human trials, it could become the first drug that doctors have to protect against the devastating loss of neurons that strokes can cause. Researchers discovered the protective molecule by chance as they sequenced the DNA of toxins in the venom of the Darling Downs funnel web spider (Hadronyche infensa) that lives in Queensland and New South Wales. Venom from three spiders was gathered for the study after scientists trapped and “milked exhaustively” three spiders on Orchid beach, about 400km north of Brisbane. The molecule, called Hi1a, stood out because it looked like two copies of another brain cell-protecting chemical stitched together. It was so intriguing that scientists decided to synthesise the compound and test its powers. “It proved to be even more potent,” said Glenn King at the University of Queensland’s centre for pain research. Strokes occur when blood flow to the brain is interrupted and the brain is starved of oxygen. About 85% of strokes are caused by blockages in blood vessels in the brain, with the rest due to bleeds when vessels rupture. Approximately six million people a year die from stroke, making it the second largest cause of death worldwide after heart attacks. © 2017 Guardian News and Media Limited

Keyword: Stroke; Neurotoxins
Link ID: 23384 - Posted: 03.21.2017

Jon Hamilton Gerard Sanacora, a professor of psychiatry at Yale University, has treated hundreds of severely depressed patients with low doses of ketamine, an anesthetic and popular club drug that isn't approved for depression. This sort of "off-label" prescribing is legal. But Sanacora says other doctors sometimes ask him, "How can you be offering this to patients based on the limited amount of information that's out there and not knowing the potential long-term risk?" Sanacora has a simple answer. "If you have patients that are likely to seriously injure themselves or kill themselves within a short period of time, and they've tried the standard treatments, how do you not offer this treatment?" he says. Dozens of clinics now offer ketamine to patients with depression. And a survey of providers in the U.S. and Canada showed that "well over 3,000" patients have been treated so far, Sanacora says. A number of small studies have found that ketamine can do something no other drug can: it often relieves even suicidal depression in a matter of hours in patients who have not responded to other treatments. Ketamine's potential as an antidepressant was recognized more than a decade ago. And studies done since then provide "compelling evidence that the antidepressant effects of ketamine infusion are both rapid and robust, albeit transient," according to a consensus statement from a task force of the American Psychiatric Association. Sanacora is one of the task force members. © 2017 npr

Keyword: Depression; Drug Abuse
Link ID: 23382 - Posted: 03.21.2017

By THOMAS FULLER SANTA ROSA, Calif. — In the heart of Northern California’s wine country, a civil engineer turned marijuana entrepreneur is adding a new dimension to the art of matching fine wines with gourmet food: cannabis and wine pairing dinners. Sam Edwards, co-founder of the Sonoma Cannabis Company, charges diners $100 to $150 for a meal that experiments with everything from marijuana-leaf pesto sauce to sniffs of cannabis flowers paired with sips of a crisp Russian River chardonnay. “It accentuates the intensity of your palate,” Mr. Edwards, 30, said of the dinners, one of which was held recently at a winery with sweeping views of the Sonoma vineyards. “We are seeing what works and what flavors are coming out.” Sonoma County, known to the world for its wines, is these days a seedbed of cannabis experimentation. The approval of recreational cannabis use by California voters in November has spurred local officials here to embrace the pot industry and the tax income it may bring. “We’re making this happen,” said Julie Combs, a member of the Santa Rosa City Council, who is helping lead an effort to issue permits to cannabis companies. “This is an industry that can really help our region.” Of the many ways in which California is on a collision course with the Trump administration, from immigration to the environment, the state’s enthusiastic embrace of legalized and regulated marijuana may be one of the biggest tests of the federal government’s power. Attorney General Jeff Sessions has equated marijuana with heroin and, on Wednesday, mentioned cannabis in the context of the “scourge of drug abuse.” © 2017 The New York Times Compan

Keyword: Drug Abuse; Pain & Touch
Link ID: 23379 - Posted: 03.20.2017

By Daniel Barron It was 4 P.M., and Andrew* had just bought 10 bags of heroin. In his kitchen, he tugged one credit-card-sized bag from the rubber-banded bundle and laid it on the counter with sacramental reverence. Pain shot through his body as he pulled a cutting board from the cabinet. Slowly, deliberately, he tapped the bag's white contents onto the board and crushed it with the flat edge of a butter knife, forming a line of fine white powder. He snorted it in one pass and shuffled back to his armchair. It was bitter, but snorting heroin was safer than injecting, and he was desperate: his prescription pain medication was gone. I met Andrew the next day in the emergency room, where he told me about the previous day's act of desperation. I admitted him to control his swelling legs and joint pain. He was also detoxing from opioids. Andrew looked older than his 69 years. His face was wrinkled with exhaustion. A frayed, tangled mop of grizzled hair fell to his shoulders. Andrew had been a satellite network engineer, first for the military, more recently for a major telecommunications company. An articulate, soft-spoken fellow, he summed up his (rather impressive) career modestly: “Well, I'd just find where a problem was and then find a way to fix it.” Yet there was one problem he couldn't fix. “Doctor, I'm always in the most terrible pain,” he said, with closed eyes. “I had no other options. I started using heroin, bought it from my neighbor to help with the pain. I'm scared stiff.” © 2017 Scientific American

Keyword: Pain & Touch; Drug Abuse
Link ID: 23378 - Posted: 03.20.2017

By Jia Naqvi Sixty percent of the calls to poison control centers for help with prescription opioid exposure involved children younger than 5. (Rich Pedroncelli/Associated Press) The phone rings once approximately every 45 minutes — that is how often poison control centers in the United States receive calls about children being exposed to prescription opioids, according to a study published Monday. Over a span of 16 years, from January 2000 until December 2015, about 188,000 calls were placed to poison control centers regarding pediatric and teenage exposure to opioids, the study published in the journal Pediatrics found. Sixty percent of the children exposed to opioids were younger than 5, while teenagers accounted for 30 percent. Pediatric exposure to opioids increased by 86 percent from 2000 to 2009 but decreased overall for all ages under 20 from 2009 until 2015, the study found. Increasing awareness among people with prescription drugs, physicians putting more thought into prescribing opioids, and prescription drug monitoring programs implemented by many states and efforts by different organizations could have contributed to the decrease in exposure, said Marcel Casavant, study author, medical director of the Central Ohio Poison Center and chief toxicologist at Nationwide Children’s Hospital in Columbus. “We are not quite sure, and so it would be good to try to sort out of all the things that we are trying, which ones are the most effective and how can we spend more time doing that,” Casavant said. © 1996-2017 The Washington Post

Keyword: Pain & Touch; Drug Abuse
Link ID: 23377 - Posted: 03.20.2017

By Taylor Beck LSD, “magic” mushrooms and mescaline have been banned in the U.S. and many other countries since the 1970s, but psychedelic medicine is making a comeback as new therapies for depression, nicotine addiction and anxiety. The drugs have another scientific use, too: so-called psychotomimetics, or mimics of psychosis, may be useful tools for studying schizophrenia. By creating a brief bout of psychosis in a healthy brain, as indigenous healers have for millennia, scientists are seeking new ways to study—and perhaps treat—mental illness. “We think that schizophrenia is a group of psychoses, which may have different causes,” says Franz Vollenweider, a psychiatrist and neuroscientist at the University of Zurich. “The new approach is to try to understand specific symptoms: hearing voices, cognitive problems, or apathy and social disengagement. If you can identify the neural bases of these, you can tailor the pharmacology.” Vollenweider and his colleagues have found an existing drug for anxiety that blocks specific effects of psilocybin, the psychoactive ingredient in magic mushrooms. When healthy people were given the drug before tripping, they did not report visual hallucinations and other common effects, according to a study published in April 2016 in European Neuropsychopharmacology. The effort is part of a burgeoning movement in pharmacology that seeks to induce psychosis to learn how to treat it. And schizophrenia desperately needs new treatments. Seventy-five percent of afflicted patients have cognitive problems. And most commonly used drugs do not treat the disorder's “negative” symptoms—apathy, social withdrawal, negative thinking—nor the cognitive impairments, which best predict how well a patient will fare in the long term. © 2017 Scientific American

Keyword: Schizophrenia; Drug Abuse
Link ID: 23375 - Posted: 03.19.2017

Doctors who limit the supply of opioids they prescribe to three days or less may help patients avoid the dangers of dependence and addiction, a new study suggests. Among patients without cancer, a single day's supply of a narcotic painkiller can result in 6 per cent of patients being on an opioid a year later, the researchers said. The odds of long-term opioid use increased most sharply in the first days of therapy, particularly after five days of taking the drugs. The rate of long-term opioid use increased to about 13 per cent for patients who first took the drugs for eight days or more, according to the report. "Awareness among prescribers, pharmacists and persons managing pharmacy benefits that authorization of a second opioid prescription doubles the risk for opioid use one year later might deter overprescribing of opioids," said senior researcher Martin Bradley. He is from the division of pharmaceutical evaluation and policy at the University of Arkansas for Medical Sciences. "The chances of long-term opioid use, use that lasts one year or more, start increasing with each additional day supplied, starting after the third day, and increase substantially after someone is prescribed five or more days, and especially after someone is prescribed one month of opioid therapy," Bradley said. The odds of chronic opioid use also increase when a second prescription is given or refilled, he noted. ©2017 CBC/Radio-Canada.

Keyword: Drug Abuse; Pain & Touch
Link ID: 23373 - Posted: 03.19.2017

By MATT RICHTEL Amid an opioid epidemic, the rise of deadly synthetic drugs and the widening legalization of marijuana, a curious bright spot has emerged in the youth drug culture: American teenagers are growing less likely to try or regularly use drugs, including alcohol. With minor fits and starts, the trend has been building for a decade, with no clear understanding as to why. Some experts theorize that falling cigarette-smoking rates are cutting into a key gateway to drugs, or that antidrug education campaigns, long a largely failed enterprise, have finally taken hold. But researchers are starting to ponder an intriguing question: Are teenagers using drugs less in part because they are constantly stimulated and entertained by their computers and phones? The possibility is worth exploring, they say, because use of smartphones and tablets has exploded over the same period that drug use has declined. This correlation does not mean that one phenomenon is causing the other, but scientists say interactive media appears to play to similar impulses as drug experimentation, including sensation-seeking and the desire for independence. Or it might be that gadgets simply absorb a lot of time that could be used for other pursuits, including partying. Nora Volkow, director of the National Institute on Drug Abuse, says she plans to begin research on the topic in the next few months, and will convene a group of scholars in April to discuss it. The possibility that smartphones were contributing to a decline in drug use by teenagers, Dr. Volkow said, was the first question she asked when she saw the agency’s most recent survey results. The survey, “Monitoring the Future,” an annual government-funded report measuring drug use by teenagers, found that past-year use of illicit drugs other than marijuana was at the lowest level in the 40-year history of the project for eighth, 10th and 12th graders. © 2017 The New York Times Company

Keyword: Drug Abuse
Link ID: 23357 - Posted: 03.15.2017

Many epilepsy patients in Australia are turning to medicinal cannabis to manage their seizures, a survey has shown. The nationwide survey found 14% of people with epilepsy had used cannabis products to manage the condition. Of those, 90% of adults and 71% of children with epilepsy, according to their parents, reported success in managing seizures. GW Pharmaceuticals doubles in value after cannabis drug success in epilepsy trial Read more Published in the journal Epilepsy & Behaviour, the Epilepsy Action Australia study, in partnership with the Lambert Initiative at the University of Sydney, surveyed 976 respondents to examine cannabis use in people with epilepsy, reasons for use and any perceived benefits self-reported by consumers. The main reason given for trying cannabis products was to seek a treatment with “more favourable” side-effects compared with standard antiepileptic drugs. The lead author of the study, Anastatsia Suraeve from the Lambert Initiative, said researchers had gained further insight into the reasons that influence use. “Despite the limitations of a retrospective online survey, we cannot ignore that a significant proportion of adults and children with epilepsy are using cannabis-based products in Australia, and many are self-reporting considerable benefits to their condition,” Suraeve said. “More systematic clinical studies are urgently needed to help us better understand the role of cannabinoids in epilepsy,” she said. © 2017 Guardian News and Media Limited

Keyword: Epilepsy; Drug Abuse
Link ID: 23342 - Posted: 03.11.2017

Ian Sample Science editor Selling high calorie foods in plain packaging could help in the battle against obesity according to a leading researcher who has won a share of the most lucrative prize in neuroscience for his work on the brain’s reward system. The colourful wrapping and attractive advertising of calorie-rich foods encourage people to buy items that put them at risk of overeating and becoming obese in the future, said Wolfram Schultz, a professor of neuroscience at the University of Cambridge. “We should not advertise, propagate or encourage the unnecessary ingestion of calories,” Schultz said at a press conference held on Monday to announce the winners of the 2017 Brain Prize. “There should be some way of regulating the desire to get more calories. We don’t need these calories.” “Colourful wrapping of high energy foods of course makes you buy more of that stuff and once you have it in your fridge, it’s in front of you every time you open the fridge and ultimately you’re going to eat it and eat too much,” he added. Schultz shares the €1m prize from the Lundbeck Foundation in Denmark with professors Peter Dayan, director of the Gatsby Computational Neuroscience Unit at UCL, and Ray Dolan, director of the Max Planck UCL Centre for Computational Psychiatry and Ageing. Together, the scientists unravelled how the brain uses rewards to learn and shape behaviour.

Keyword: Drug Abuse; Obesity
Link ID: 23320 - Posted: 03.06.2017

By Alistair Steele, CBC News The opioid crisis that's claiming lives across the country has taken a particularly sinister turn in the nation's capital. Or so it appears. Much of the public discussion — and a good deal of the news coverage — surrounding the growing number of deaths by opioid overdose in Ottawa has concentrated on the cruel toll the drugs are taking on the city's teenagers, particularly those living in the western suburb of Kanata. The fake prescription pills they take recreationally are cheap and easy to find, but they can also be laced with potentially lethal doses of fentanyl. This tragic trend was given a fresh, young face when Grade 9 student Chloe Kotval, just 14, died from an overdose on Valentine's Day. Police later confirmed pills found near the girl's body contained fentanyl. In a statement released the day of their daughter's funeral, Kotval's parents wrote: "We are concerned about the epidemic nature of the use of high-grade pharmaceuticals amongst young people and their lack of knowledge about them — the consequences of using them are real and terrible." While families have every right to be concerned and to prepare for the worst, there's no evidence showing young people are any more susceptible to opioid overdoses than any other group of drug users in Ottawa. Sean O'Leary, whose own teenage daughter became addicted to counterfeit percocets, told CBC about coming home one night to find a 17-year-old boy who had overdosed in his garage. ©2017 CBC/Radio-Canada.

Keyword: Drug Abuse; Pain & Touch
Link ID: 23312 - Posted: 03.04.2017

Recently, an international team of researchers reported that the cerebellum may play a previously unforeseen role in brain alterations associated with the addictive consumption of drugs. Until now, the cerebellum—which has historically been viewed by most neuroscientists as primarily the seat of fine-tuned motor control and coordination—has gone under the radar of drug addiction specialists. The latest reports linking the cerebellum and drug addiction were based on a broad range of groundbreaking research published over the past two years. These findings were recently compiled and featured in two different journals: Neuroscience & Biobehavioral Reviews and the Journal of Neuroscience. Bringing all of this research together was the brainchild of Marta Miquel, professor in the research group Addiction and Neuroplasticity at the Universitat Jaume I (UJI) in Spain. Miguel spearheaded her own original research as well as the initiative to collect multidisciplinary research from a broad spectrum of international institutions and to present these cerebellar findings cohesively under one umbrella. (Cerebellar is the sister word to cerebral and means “relating to or located in the cerebellum.”) In addition to the UJI team, contributing research for this compilation of studies on the cerebellum and addiction came from the University of Cambridge and University of Leeds (United Kingdom); University of Turin (Italy); Universidad Veracruzana (Mexico); the University of Kentucky, Washington State University, and McLean Hospital Translational Neuroscience Laboratory and Mailman Research Center (USA). Psychology Today © 1991-2017 Sussex Publishers, LLC

Keyword: Drug Abuse
Link ID: 23301 - Posted: 03.02.2017

By Jessica Hamzelou Fancy a coffee after that cigarette? Smoking makes you drink more caffeinated drinks, possibly by changing your metabolism so that you break down caffeine quicker, pushing you to drink more to get the same hit. That’s according to Marcus Munafò at the University of Bristol, UK, and his colleagues who have looked into the smoking and drinking habits of about 250,000 people. It’s impossible to do a randomised controlled trial (the most rigorous kind of scientific trial) when it comes to smoking, because it would be unethical to ask a randomly selected group of people to smoke. The next best thing is to study huge biobanks of health data. These biobanks contain information about people’s genes, diets and lifestyles. To explore the relationship between smoking and caffeine, Munafo and his colleagues analysed data from biobanks in the UK, Norway and Denmark. They were particularly interested in people who had inherited a variant of a gene that has already been shown to increase cigarette smoking. The team found that people who had this gene variant also consumed more coffee – but only if they smoked. British people with the same variant also drank more tea, although their Danish and Norwegian counterparts didn’t. This is probably due to cultural differences, says Munafò. “People in Norway and Denmark don’t chain drink tea in the same way that people in the UK do,” he says. © Copyright Reed Business Information Ltd.

Keyword: Drug Abuse
Link ID: 23287 - Posted: 02.27.2017

Allison Aubrey If you drink more alcohol than you want to or should, you're not alone. A nationwide survey by the National Institutes of Health found that 28 percent of adults in the U.S. are heavy drinkers or drink more than is recommended. Yet, most heavy drinkers don't get the help they need. "The biggest problem we have in the field is that less than 10 percent of individuals with an alcohol use disorder get any treatment whatsoever," says George Koob, director of the National Institute on Alcohol Abuse and Alcoholism. Part of the challenge, researchers say, is that many drinkers don't realize that a medicine long used to help people addicted to opioids quit their drug habit can help alcoholics and other heavy drinkers cut back, too. "I thought my only option was AA," John tells NPR. We've agreed to use only his middle name; disclosing his trouble with alcohol publicly, he says, would jeopardize his business. He's a 47-year-old professional who says he started out as a social drinker — a few beers with his softball team after a game. But he sank into a deep depression after several deaths in his family, and sought "solace the bottle," he says. "I wanted to numb my thoughts," says John. He'd often start with hard liquor in the morning, John says, and it wasn't uncommon to have eight drinks or more before the end of the day. © 2017 npr

Keyword: Drug Abuse; Pain & Touch
Link ID: 23286 - Posted: 02.27.2017

By Christine Vestal NEW YORK — After a 12-year battle with debilitating abdominal conditions that forced her to stop working, marijuana has helped Lynn Sabulski feel well enough to look for a job. Sabulski is among nearly 14,000 patients in New York state who are certified to use medical marijuana for one of 10 ­conditions, including her ­primary diagnosis, inflammatory bowel disease. Marijuana doesn’t address her underlying disease, but it does relieve her painful symptoms. Nationwide, an estimated 1.4 million patients in 28 states and the District of Columbia use legal medical marijuana for a varying list of conditions. A much smaller number of patients in 16 states use limited extracts of the plant, primarily to treat seizure disorders. In the midst of an opioid crisis, some medical practitioners and researchers say they think that greater use of marijuana for pain relief could result in fewer people using the highly addictive prescription painkillers that led to the epidemic. A 2016 study by researchers at Johns Hopkins Bloomberg School of Public Health found that states with medical marijuana laws had 25 percent fewer opioid overdose deaths than states that do not have medical marijuana laws. And another study published in Health Affairs last year found that prescriptions for opioid painkillers such as OxyContin, Vicodin and Percocet paid for by Medicare dropped substantially in states that adopted medical marijuana laws. © 1996-2017 The Washington Post

Keyword: Drug Abuse; Pain & Touch
Link ID: 23285 - Posted: 02.27.2017

Geoff Brumfiel When the half-brother of North Korean leader Kim Jong Un collapsed at a Malaysian airport last week, poisoning was instantly suspected. But on Friday, Malaysian authorities revealed that an autopsy had turned up not just any poison, but a rare nerve agent known as VX. VX is among the deadliest chemical weapons ever devised. A colorless, odorless liquid, similar in consistency to motor oil, it kills in tiny quantities that can be absorbed through the skin. A relative of the nerve agent Sarin, VX disrupts communications between nerves and muscles. Victims of VX initially experience nausea and dizziness. Without an antidote, the chemical eventually paralyzes the diaphragm, causing suffocation. That may have been the fate of Kim Jong Nam, the estranged half-brother of North Korea's leader. Security footage showed that Kim was approached by two women who appeared to cover his face with a cloth. Moments later, he fell ill and sought help. He died before reaching a hospital. If the Malaysian analysis is correct and VX was the culprit, that would seem to suggest that the North Korean state itself is behind the killing. "Hardly anybody has it," says Dan Kaszeta, a chemical weapons expert and consultant based in London. The U.S. has destroyed nearly all of its stocks of VX in recent years. North Korea is among the few states in the world that have an active chemical weapons program. It is not a signatory to the Chemical Weapons Convention, which bans the use of such weapons. © 2017 npr

Keyword: Neurotoxins
Link ID: 23282 - Posted: 02.25.2017

By Alice Klein The proof is in the packaging. Making all cigarette packets look the same reduces the positive feelings smokers associate with specific brands and encourages quitting, Australian research shows. The findings come ahead of the UK and Ireland introducing plain tobacco packaging in May. Australia was the first nation to introduce such legislation in December 2012. Since then, all cigarettes have been sold in plain olive packets with standard fonts and graphic health warnings. The primary goal was to make cigarettes less appealing so that people would not take up smoking in the first place. But an added bonus has been the number of existing smokers who have ditched the habit. Between 2010 and 2013, the proportion of daily smokers in Australia dropped from 15.1 to 12.8 per cent – a record decline. The number of calls to quit helplines also increased by 78 per cent after the policy change. Brand betrayal This drop in smoking popularity can be partly explained by a loss of brand affinity, says Hugh Webb at the Australian National University in Canberra. People derive a sense of belonging and identity from brands, he says. For example, you may see yourself as a “Mac person” or a “PC person” and feel connected to other people who choose that brand. “Marketers are extremely savvy about cultivating these brand identities.” © Copyright Reed Business Information Ltd

Keyword: Drug Abuse; Attention
Link ID: 23271 - Posted: 02.24.2017

By WINNIE HU Ruth Brunn finally said yes to marijuana. She is 98. She pops a green pill filled with cannabis oil into her mouth with a sip of vitamin water. Then Ms. Brunn, who has neuropathy, settles back in her wheelchair and waits for the jabbing pain in her shoulders, arms and hands to ebb. “I don’t feel high or stoned,” she said. “All I know is I feel better when I take this.” Ms. Brunn will soon have company. The nursing home in New York City where she lives, the Hebrew Home at Riverdale, is taking the unusual step of helping its residents use medical marijuana under a new program to treat various illnesses with an alternative to prescription drugs. While the staff will not store or administer pot, residents are allowed to buy it from a dispensary, keep it in locked boxes in their rooms and take it on their own. From retirement communities to nursing homes, older Americans are increasingly turning to marijuana for relief from aches and pains. Many have embraced it as an alternative to powerful drugs like morphine, saying that marijuana is less addictive, with fewer side effects. For some people, it is a last resort when nothing else helps. Marijuana, which is banned by federal law, has been approved for medical use in 29 states, including New York, and the District of Columbia. Accumulating scientific evidence has shown its effectiveness in treating certain medical conditions. Among them: neuropathic pain, severe muscle spasms associated with multiple sclerosis, unintentional weight loss, and vomiting and nausea from chemotherapy. There have also been reports that pot has helped people with Alzheimer’s disease and other types of dementia as well as Parkinson’s disease. © 2017 The New York Times Company

Keyword: Drug Abuse; Alzheimers
Link ID: 23255 - Posted: 02.20.2017

Jon Hamilton Researchers have created mice that appear impervious to the lure of cocaine. Even after the genetically engineered animals were given the drug repeatedly, they did not appear to crave it the way typical mice do, a team reports in Nature Neuroscience. "They didn't keep going into the room where they received the cocaine and they seemed to be just as happy exploring all around the cage," says Shernaz Bamji, a professor in the Department of Cellular and Physiological Sciences at the University of British Columbia in Vancouver. "Addiction is a form of learning," Bamji says. And somehow, these mice never learned to associate the pleasurable feelings produced by cocaine with the place where they received the drug. The result was startling because the scientists thought these mice would be especially susceptible to addiction. "We repeated the experiment several times to see if we had made a mistake," Bamji says. The reason for the team's surprise had to do with proteins that affect learning. The animals had been genetically engineered to produce high levels of proteins called cadherins in the brain's "reward circuit," which plays an important role in addiction. And genetic studies have suggested that people with high levels of cadherins are more susceptible to drug addiction. Cadherins act a bit like glue, binding cells together. Usually this glue enhances learning by strengthening the connections, or synapses, between brain cells. © 2017 npr

Keyword: Drug Abuse; Learning & Memory
Link ID: 23228 - Posted: 02.14.2017

By BENEDICT CAREY The number of retirement-age Americans taking at least three psychiatric drugs more than doubled between 2004 and 2013, even though almost half of them had no mental health diagnosis on record, researchers reported on Monday. The new analysis, based on data from doctors’ office visits, suggests that inappropriate prescribing to older people is more common than previously thought. Office visits are a close, if not exact, estimate of underlying patient numbers. The paper appears in the journal JAMA Internal Medicine. Geriatric medical organizations have long warned against overprescribing to older people, who are more susceptible to common side effects of psychotropic drugs, such as dizziness and confusion. For more than 20 years, the American Geriatrics Society has published the so-called Beers Criteria for potentially inappropriate use, listing dozens of drugs and their mutual interactions. In that time, prescription rates of drugs like antidepressants, sleeping pills and painkillers nonetheless generally increased in older people, previous studies have found. The new report captures one important dimension, the rise in so-called polypharmacy — three drugs or more — in primary care, where most of the prescribing happens. Earlier research has found that elderly people are more likely to be on at least one psychiatric drug long term than younger adults, even though the incidence of most mental disorders declines later in life. “I was stunned to see this, that despite all the talk about how polypharmacy is bad for older people, this rate has doubled,” said Dr. Dilip Jeste, a professor of psychiatry and neurosciences at the University of California, San Diego, who was not involved in the new work. © 2017 The New York Times Company

Keyword: Depression; Drug Abuse
Link ID: 23225 - Posted: 02.14.2017