Chapter 4. The Chemistry of Behavior: Neurotransmitters and Neuropharmacology

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Links 1 - 20 of 1934

By ALAN SCHWARZ A sharp rise in visits to emergency rooms and calls to poison control centers nationwide has some health officials fearing that more potent and dangerous variations of a popular drug known as spice have reached the nation’s streets, resulting in several deaths. In the first three weeks of April, state poison control centers received about 1,000 reports of adverse reactions to spice — the street name for a family of synthetic substances that mimic the effects of marijuana — more than doubling the total from January through March, according to the American Association of Poison Control Centers. The cases, which can involve spice alone or in combination with other substances, have appeared four times as often this year as in 2014, the organization said. On Thursday alone there were 172 reports, by far the most in one day this year. Health departments in Alabama, Mississippi and New York have issued alerts this month about more spice users being rushed to hospitals experiencing extreme anxiety, violent behavior and delusions, with some of the cases resulting in death. Similar increases have occurred in Arizona, Florida, New Jersey and Texas. The total number of fatalities nationwide this year is not available, health officials said. One person in Louisiana died Wednesday and two others were in intensive care, said Mark Ryan, the director of the Louisiana Poison Center. “We had one hospital in the Baton Rouge area that saw over 110 cases in February. That’s a huge spike,” Dr. Ryan said. “There’s a large amount of use going on. When one of these new ingredients — something that’s more potent and gives a bigger high — is released and gets into distribution, it can cause these more extreme effects.” © 2015 The New York Times Compan

Keyword: Drug Abuse
Link ID: 20848 - Posted: 04.25.2015

|By Tara Haelle When it comes to treating attention-deficit hyperactivity disorder (ADHD) a lot of kids are getting the meds they need—but they may be missing out on other treatments. Despite clinical guidelines that urge that behavioral therapy always be used alongside medication, less than half of the children with ADHD received therapy as part of treatment in 2009 and 2010, according to the first nationally representative study of ADHD treatment in U.S. children. The findings, published online March 31 in The Journal of Pediatrics, come from data collected during that period on 9,459 children, aged four to 17, with diagnosed ADHD—just before the American Academy of Pediatrics (AAP) issued its clinical practice guidelines on treatments of the condition in 2011. They provide a baseline for comparison when the next report is issued in 2017. Medication alone was the most common treatment for children with ADHD: 74 percent had taken medication in the previous week whereas 44 percent had received behavioral therapy in the past year. Just under a third of children of all ages had received both medication and behavioral therapy, the AAP-recommended treatment for all ages. “It’s not at all surprising that medication is the most common treatment,” says Heidi Feldman, a professor of developmental and behavioral pediatrics at Stanford University School of Medicine who served on the AAP clinical practice guidelines committee. “It works very effectively to reduce the core symptoms of the condition,” she adds, “and stimulants are relatively safe if used properly. The limitation of stimulant medications for ADHD is that studies do not show a long-term functional benefit from medication use.” © 2015 Scientific American

Keyword: ADHD
Link ID: 20827 - Posted: 04.21.2015

By ALAN SCHWARZ Fading fast at 11 p.m., Elizabeth texted her dealer and waited just 30 minutes for him to reach her third-floor New York apartment. She handed him a wad of twenties and fifties, received a tattered envelope of pills, and returned to her computer. Her PowerPoint needed another four hours. Investors in her health-technology start-up wanted re-crunched numbers, a presentation begged for bullet points and emails from global developers would keep arriving well past midnight. She gulped down one pill — pale orange, like baby aspirin — and then, reconsidering, took one of the pinks, too. “O.K., now I can work,” Elizabeth exhaled. Several minutes later, she felt her brain snap to attention. She pushed her glasses up her nose and churned until 7 a.m. Only then did she sleep for 90 minutes, before arriving at her office at 9. The pills were versions of the drug Adderall, an amphetamine-based stimulant prescribed for attention deficit hyperactivity disorder that many college students have long used illicitly while studying. Now, experts say, stimulant abuse is graduating into the work force. But in interviews, dozens of people in a wide spectrum of professions said they and co-workers misused stimulants like Adderall, Vyvanse and Concerta to improve work performance. Most spoke on the condition of anonymity for fear of losing their jobs or access to the medication. Doctors and medical ethicists expressed concern for misusers’ health, as stimulants can cause anxiety, addiction and hallucinations when taken in high doses. But they also worried about added pressure in the workplace — where the use by some pressures more to join the trend. © 2015 The New York Times Company

Keyword: Drug Abuse; ADHD
Link ID: 20821 - Posted: 04.20.2015

By KATIE THOMAS Last fall, an article in the American Journal of Psychiatry caught the attention of specialists who treat borderline personality disorder, an intractable condition for which no approved drug treatment exists. The article seemed to offer a glimmer of hope: The antipsychotic drug Seroquel XR reduced some of the disorder’s worst symptoms in a significant number of patients. “It was an exciting development,” recalled Mark F. Lenzenweger, a professor at Binghamton University and Weill Cornell Medical College and an expert in borderline personality disorder. In the realm of clinical trials, however, reality is sometimes far messier than the tidy summaries in medical journals. A closer look at the Seroquel XR study shows just how complicated things can get when a clinical trial involves psychiatric disorders and has its roots in intersecting and sometimes competing interests: a drug company looking to hold onto sales of a best-selling drug, a prominent academic with strong ties to the pharmaceutical industry and a university under fire for failing to protect human study subjects. The trial was paid for by AstraZeneca, the maker of Seroquel XR, and was conducted by Dr. S. Charles Schulz, the head of psychiatry at the University of Minnesota. Two of the study participants were living in a residential treatment facility for sex offenders and may have lied about their diagnosis to qualify for the trial. One of those men slipped the drugs to unwitting treatment center residents and staff, an alarming development that nevertheless did not seem to ruffle the university oversight board that is charged with looking into such episodes. The University of Minnesota’s clinical trial practices are now under intense scrutiny. In February, a panel of outside experts excoriated the university for failing to properly oversee clinical trials and for paying inadequate attention to the protection of vulnerable subjects. The review, commissioned by the university after years of criticism of its research practices, singled out Dr. Schulz and his department of psychiatry, describing “a culture of fear” that pervaded the department. © 2015 The New York Times Company

Keyword: Schizophrenia
Link ID: 20814 - Posted: 04.18.2015

By SABRINA TAVERNISE E-cigarettes have arrived in the life of the American teenager. Use of the devices among middle- and high school students tripled from 2013 to 2014, according to federal data released on Thursday, bringing the share of high school students who use them to 13 percent — more than smoke traditional cigarettes. About a quarter of all high school students and 8 percent of middle school students — 4.6 million young people altogether — used tobacco in some form last year. The sharp rise of e-cigarettes, together with a substantial increase in the use of hookah pipes, led to 400,000 additional young people using a tobacco product in 2014, the first increase in years, though researchers pointed out the percentage of the rise fell within the report’s margin of error. But the report also told another story. From 2011 to 2014, the share of high school students who smoked traditional cigarettes declined substantially, to 9 percent from 16 percent, and use of cigars and pipes ebbed too. The shift suggested that some teenage smokers may be using e-cigarettes to quit. Smoking is still the single-biggest cause of preventable death in the United States, killing more than 480,000 Americans a year, and most scientists agree that e-cigarettes, which deliver the nicotine but not the dangerous tar and other chemicals, are likely to be far less harmful than traditional cigarettes. The numbers came as a surprise and seemed to put policy makers into uncharted territory. The Food and Drug Administration took its first tentative step toward regulating e-cigarettes last year, but the process is slow, and many experts worry that habits are forming far faster than rules are being written. Because e-cigarettes are so new, scientists are still gathering evidence on their long-term health effects, leaving regulators scrambling to gather data. © 2015 The New York Times Company

Keyword: Drug Abuse
Link ID: 20811 - Posted: 04.18.2015

by Beth Mole Small doses of lead may have big impacts on reading and math scores, scientists report April 7 in Environmental Health. Researchers looked at third grade test scores and levels of lead in blood samples from 58,650 students in Chicago public schools. As little as 2 micrograms of lead per deciliter of blood was associated with lower reading and math scores. The Centers for Disease Control and Prevention recommends that anything above 5 micrograms per deciliter is of concern. The researchers estimate that childhood lead levels at or above 5 micrograms per deciliter of blood accounted for as many as 25 percent of the children in the study failing reading and math standardized tests. The findings confirm that lead exposure, even at low doses, is associated with poor school performance. © Society for Science & the Public 2000 - 2015

Keyword: Development of the Brain; Neurotoxins
Link ID: 20809 - Posted: 04.18.2015

By Laura Sanders To drive a rat to drink, make it smoke first. Rats dependent on nicotine escalate their drinking more quickly than rats that haven’t been exposed to nicotine, researchers report in the April 15 Journal of Neuroscience. The results help explain why alcohol and tobacco addictions in people often go hand in hand. After nicotine injections, rats that had previously been exposed to alcohol dosed themselves with more alcohol than rats unexposed to nicotine did. Scientists were able to curb this booziness: Rats injected with a compound that made brain cells ignore nicotine did not boost their intake of alcohol. The double whammy of nicotine and alcohol dependence may be due to a select group of nerve cells throughout the rat brain that respond to this nicotine-aided drinking, Olivier George of the Scripps Research Institute in La Jolla, Calif., and colleagues found. If a similar response happens in humans, studying these particular nerve cells might ultimately lead to better ways to curb both alcohol and tobacco dependencies, the researchers write. R. Leão et al. Chronic nicotine activates stress/reward-related brain regions and facilitates the transition to compulsive alcohol drinking. Journal of Neuroscience. Vol. 35, April 15, 2015. doi:10.1523/JNEUROSCI.3302-14.2015. © Society for Science & the Public 2000 - 2015.

Keyword: Drug Abuse
Link ID: 20799 - Posted: 04.15.2015

By Lenny Bernstein Children with two of the most severe forms of epilepsy can suffer scores of seizures each day, as well as long-term physical and cognitive problems. The two conditions, Dravet and Lennox-Gastaut syndromes, are quite rare but unfortunately very resistant to treatment with current epilepsy drugs. Now a compound found in marijuana plants has shown promising results in a preliminary study, during which it sharply reduced the number of seizures suffered by these children. Some were even seizure-free after three months of taking the drug, cannabidiol, the research showed. "We're very encouraged by the data," said Orrin Devinsky, director of the NYU Langone Comprehensive Epilepsy Center and leader of the research. A more rigorous study of cannabidiol's impact has begun and will help determine how effective it really is, he said. In making cannabidiol, the marijuana plant's psychoactive material (THC) was removed. A 99 percent pure liquid version of the drug was given for three to six months to 137 people with the two syndromes. Most were children (the subjects ranged in age from 2 to 26), and before the experiment they suffered a disturbing average of 95.3 convulsive seizures every month. Convulsive seizures are the more severe, violent kind; people with epilepsy can experience a wide variety of seizures, including some mild enough that they appear to be merely staring into space for a few seconds. Some of the subjects had taken as many as 10 different epilepsy drugs, with little success.

Keyword: Epilepsy; Drug Abuse
Link ID: 20796 - Posted: 04.14.2015

by Bethany Brookshire In 2011, a group of scientists “turned mice gay.” The only issue is, of course, they didn’t. Rather, Yi Rao and colleagues at Peking University in Beijing, China, showed that male mice will cheerfully mount both male and female mice, as long as their brains are deficient in one chemical messenger: serotonin. The paper, published in Nature, received plenty of media coverage. Now, two other research groups report seemingly opposite findings: Male mice with no serotonin in their brains still prefer female mice to males. The researchers contend that serotonin is about social communication and impulsive behaviors, not sex. Mounting behavior aside, sexual preference in mice is not about “turning mice gay.” It never has been. Instead, it’s about the role that a single chemical can play in animal behavior. And it’s about what, exactly, those behaviors really mean. Serotonin serves as a messenger between cells. It plays important roles in mood. Serotonin-related drugs are used to treat some forms of migraine. And of course, serotonin plays a role in the psychedelic effects of recreational drugs such as hallucinogens. So when the Peking University group set out to show serotonin’s role in sexual preference, they attacked it from several angles. They used mice that had been genetically engineered to lack the brain cells that usually produce serotonin. They used a chemical to deplete serotonin in the brains of normal mice. And they created another strain of mice that lacked the enzyme that makes serotonin in the brain. © Society for Science & the Public 2000 - 2015

Keyword: Sexual Behavior
Link ID: 20787 - Posted: 04.11.2015

Leana Wen Every doctor and nurse in our hospital's emergency room knew Jerome. He was one of our regulars. In his 20s, he had back problems that led him to become addicted to prescription painkillers. That habit proved too expensive, and he switched to heroin. Jerome used to come to the ER nearly every week. Often, he just wanted a sandwich and someone to talk to. He had lost his job and his home. Several months ago, he decided he had to quit heroin. We helped him with health insurance so that he could find a primary care doctor. Our social worker connected him with addiction treatment, including medications and mental health counseling. He was also working on rekindling a relationship with his estranged family. One day, paramedics brought Jerome to the ER. They had found him in an abandoned building. He'd relapsed and was shooting heroin. A friend saw him unconscious and called for help. By the time paramedics arrived, he wasn't breathing and his heart had stopped beating. In the ER, we tried to resuscitate him for nearly an hour. We weren't successful. In Baltimore, where I serve as health commissioner, more people die from drug and alcohol overdoses than from homicide. In 2013, there were 246 deaths related to drugs and alcohol, compared with 235 homicides. © 2015 NPR

Keyword: Drug Abuse
Link ID: 20783 - Posted: 04.11.2015

Do Alcoholics Anonymous participants do better at abstinence than nonparticipants because they are more motivated? Or is it because of something inherent in the A.A. program? How researchers answered these questions in a recent study offers insight into challenges of evidence-based medicine and evidence-informed policy. The study, published in the journal Alcoholism: Clinical and Experimental Research, teased apart a treatment effect (improvement due to A.A. itself) and a selection effect (driven by the type of people who seek help). The investigators found that there is a genuine A.A. treatment effect. Going to an additional two A.A. meetings per week produced at least three more days of alcohol abstinence per month. Separating treatment from selection effects is a longstanding problem in social and medical science. Their entanglement is one of the fundamental ways in which evidence of correlation fails to be a sign of causation. For many years, researchers and clinicians have debated whether the association of A.A. with greater abstinence was caused by treatment or a correlation that arises from the type of people who seek it. Such confounding is often addressed with an experiment in which individuals are randomly assigned to either a treatment or a nontreatment (or control) group in order to remove the possibility of self-selection. The treatment effect is calculated by comparing outcomes obtained by participants in each group. Several studies of A.A. have applied this approach. For instance, Kimberly Walitzer, Kurt Dermen and Christopher Barrick randomized alcoholics to receive treatment that strongly encouraged and supported A.A. participation or a control group. The former exhibited a greater degree of abstinence. In an ideal randomized controlled trial (R.C.T.), everyone selected for treatment receives it and no one in the control group does. The difference in outcomes is the treatment effect, free of bias from selection. That’s the ideal. However, in practice, randomized controlled trials can still suffer selection problems. © 2015 The New York Times Company

Keyword: Drug Abuse
Link ID: 20767 - Posted: 04.08.2015

Arran Frood A psychedelic drink used for centuries in healing ceremonies is now attracting the attention of biomedical scientists as a possible treatment for depression. Researchers from Brazil last month published results from the first clinical test of a potential therapeutic benefit for ayahuasca, a South American plant-based brew1. Although the study included just six volunteers and no placebo group, the scientists say that the drink began to reduce depression in patients within hours, and the effect was still present after three weeks. They are now conducting larger studies that they hope will shore up their findings. The work forms part of a renaissance in studying the potential therapeutic benefits of psychedelic or recreational drugs — research that was largely banned or restricted worldwide half a century ago. Ketamine, which is used medically as an anaesthetic, has shown promise as a fast-acting antidepressant; psilocybin, a hallucinogen found in ‘magic mushrooms’, can help to alleviate anxiety in patients with advanced-stage cancer2; MDMA (ecstasy) can alleviate post-traumatic stress disorder; and patients who experience debilitating cluster headaches have reported that LSD eases their symptoms. Ayahuasca, a sacramental drink traditionally brewed from the bark of a jungle vine (Banisteriopsis caapi) and the leaves of a shrub (Psychotria viridis), contains ingredients that are illegal in most countries. But a booming ayahuasca industry has developed in South America, where its religious use is allowed, and where thousands of people each year head to rainforest retreats to sample its intense psychedelic insights. © 2015 Nature Publishing Group,

Keyword: Depression; Drug Abuse
Link ID: 20765 - Posted: 04.07.2015

by Bethany Brookshire A new round of dietary do’s and don’ts accompanied last month’s scientific report on the latest food research, summarizing everything from aspartame to saturated fats. The report puts eggs back on the menu. High dietary cholesterol is no longer linked to blood cholesterol in most healthy people. But what grabbed the headlines? Coffee, of course. Many of us are happy to raise a mug to our legal stimulant of choice, especially with the report’s suggestion that three to five cups of joe get a pass. But where do these numbers come from? What science do nutrition experts take into account to determine whether coffee is harmful or safe? And — perhaps the most important question — what does “three to five cups” really mean? The good news for coffee comes from the 2015 Dietary Guidelines Advisory Committee, a group of experts in nutrition and health appointed by the Department of Health and Human Services and the U.S. Department of Agriculture to review the science behind what Americans should eat. The report, released February 19, is not the be-all-end-all of what should be on our plates and in our cups. Instead, it’s a scientific report intended to help the HHS and USDA make policy decisions for the next edition of the Dietary Guidelines for Americans, due out later this year. This is the first time the U.S. Dietary Guidelines have addressed coffee at all. But now, there is enough science on coffee to make a closer look worthwhile, says Tom Brenna, a food scientist at Cornell University and a member of the Committee. “There was so much evidence out there,” he says. “Instead of just five or six papers on the subject, there’s a huge number.” © Society for Science & the Public 2000 - 2015

Keyword: Drug Abuse
Link ID: 20758 - Posted: 04.06.2015

By Shereen Lehman (Reuters Health) - Children exposed to tobacco smoke at home are up to three times more likely to have attention deficit hyperactive disorder (ADHD) as unexposed kids, according to a new study from Spain. The association was stronger for kids with one or more hours of secondhand smoke exposure every day, the authors found. And the results held when researchers accounted for parents' mental health and other factors. "We showed a significant and substantial dose-response association between (secondhand smoke) exposure in the home and a higher frequency of global mental problems," the authors write in Tobacco Control, online March 25. According to the Centers for Disease Control and Prevention, two of every five children in the US are exposed to secondhand smoke regularly. Alicia Padron of the University of Miami Miller School of Medicine in Florida and colleagues in Spain analyzed data from the 2011 to 2012 Spanish National Health Interview Survey, in which parents of 2,357 children ages four to 12 reported the amount of time their children were exposed to secondhand smoke every day. The parents also filled out questionnaires designed to evaluate their children's mental health. According to the results, about eight percent of the kids had a probable mental disorder. About 7% of the kids were exposed to secondhand smoke for less than one hour per day, and 4.5% were exposed for an hour or more each day. © 2015 Scientific American,

Keyword: ADHD; Drug Abuse
Link ID: 20753 - Posted: 04.04.2015

Founded by two men in Akron, Ohio, in 1935, Alcoholics Anonymous has since spread around the world as a leading community-based method of overcoming alcohol dependence and abuse. Many people swear by the 12-step method, which has become the basis of programs to treat the abuse of drugs, gambling, eating disorders and other compulsive behaviors. But not everyone's a fan. In a recent critique of AA, author Gabrielle Glaser writes in the April issue of The Atlantic that, "Nowhere in the field of medicine is treatment less grounded in modern science." Glaser, whose 2013 book, Her Best-Kept Secret, explores what she calls "the epidemic of female drinking" in the U.S., says recent research on the brain suggests that the abstinence advocated by AA isn't the only solution — or even the best for many people. Cognitive therapy combined with the medication naltrexone, Glaser says, can help ease cravings and has been shown in some studies to help some problem drinkers learn to drink moderately without quitting. Glaser's magazine story has drawn fire from defenders of AA, including Huffington Post writer Tommy Rosen, who calls himself "a person in long-term recovery (23 years) who overcame severe drug addiction and alcoholism in great part due to the 12 Steps." Glaser's article, Rosen writes, is "painfully one-sided." Therapist and psychology reporter Robi Ludwig told Glaser and the host of MSNBC's program All in With Chris Hayes last week that she thinks it's "very dangerous to put out the idea that AA doesn't work. Does it work for everybody? No. There's not going to be one form of treatment that works for everybody." © 2015 NPR

Keyword: Drug Abuse
Link ID: 20729 - Posted: 03.28.2015

Claudia Dreifus Twenty-three states and the District of Columbia have legalized medical marijuana, but scientific research into its appropriate uses has lagged. Dr. Mark Ware would like to change that. Dr. Ware, 50, is the director of the Canadian Consortium for the Investigation of Cannabinoids and the director of clinical research of the Alan Edwards Pain Management Unit of McGill University Health Center. Medical marijuana has been legal in Canada for 16 years, and Dr. Ware, a practicing physician, studies how his patients take the drug and under what conditions it is effective. We spoke for two hours at the recent meeting of the American Association for the Advancement of Science and later by telephone. Our interviews have been condensed and edited for space. Q. How did you become interested in the medical possibilities of cannabis? A. In the late 1990s, I was working in Kingston, Jamaica, at a clinic treating people with sickle cell anemia. My British father and Guyanese mother had raised me in Jamaica, and I’d attended medical school there. One day, an elderly Rastafarian came for his annual checkup. I asked him, “What are your choices of medicines?” He leaned over the table and said, “You must study the herb.” That night, I went back to my office and looked up “cannabis and pain.” What I found were countless anecdotes from patients who’d obtained marijuana either legally or not and who claimed good effect with a variety of pain-related conditions. There were also the eye-opening studies showing that the nervous system had specific receptors for cannabinoids and that these receptors were located in areas related to pain. Everything ended with, “More studies are needed.” So I thought, “This is what I should be doing; let’s go!” © 2015 The New York Times Company

Keyword: Drug Abuse; Pain & Touch
Link ID: 20713 - Posted: 03.24.2015

By Brian Handwerk In the U.S., legal hurdles have long hampered research into marijuana. But as more states approve medical and even recreational marijuana, scientific inquiries have spiked, especially studies aimed at finding out what exactly is in today's weed—and what it does to our bodies. In Colorado, which made marijuana legal in November 2012, the latest results show that the pot lining store shelves is much more potent than the weed of 30 years ago. But the boost in power comes at a cost—modern marijuana mostly lacks the components touted as beneficial by medical marijuana advocates, and it is often contaminated with fungi, pesticides and heavy metals. “There's a stereotype, a hippy kind of mentality, that leads people to assume that growers are using natural cultivation methods and growing organically," says Andy LaFrate, founder of Charas Scientific, one of eight Colorado labs certified to test cannabis. "That's not necessarily the case at all." LaFrate presented his results this week at a meeting of the American Chemical Society (ACS) in Denver. LaFrate says he's been surprised at just how strong most of today's marijuana has become. His group has tested more than 600 strains of marijuana from dozens of producers. Potency tests, the only ones Colorado currently requires, looked at tetrahydrocannabinol (THC), the psychoactive compound that produces the plant's famous high. They found that modern weed contains THC levels of 18 to 30 percent—double to triple the levels that were common in buds from the 1980s. That's because growers have cross-bred plants over the years to create more powerful strains, which today tout colorful names like Bruce Banner, Skunkberry and Blue Cookies.

Keyword: Drug Abuse
Link ID: 20712 - Posted: 03.24.2015

By Camilla Turner It is one of life’s most enduring mysteries. A question that music, poetry, myth and legend has, for thousands of years, tried but failed to answer. However, we may now be a step closer to discovering what love is, thanks to a scientific study that has obtained the first empirical evidence of love-related alterations in the brain. A team of researchers from universities in China and New York used MRI scans to track the physical effects of love on the brain and has pieced together a “love map” of the human mind. The study found that several areas of the brain showed increased activity in those who were in love, including in the parts of the brain linked to reward and motivation. The researchers said their results shed light on the “underlying mechanisms of romantic love” and would pave the way for a brain scan that could act as a “love test”. Scientists recruited 100 students from Southwest University in Chongqing, China, who were divided into three groups according to their relationship status: an “in-love” group, comprised of those who were in love at the time; an “ended-love” group, who had recently ended loving relationships; and a “single” group, who had never been in love. Participants were told not to think of anything while their brains were scanned, so that researchers could monitor the differences between the brains of students in all three groups. © Copyright of Telegraph Media Group Limited 2015

Keyword: Sexual Behavior
Link ID: 20692 - Posted: 03.17.2015

By John Horgan In 1990 The New York Times published a front-page article by Lawrence Altman, a reporter with a medical degree, announcing that scientists had discovered “a link between alcoholism and a specific gene.” The evidence for the "feel-good gene," which supposedly reduces anxiety, is flimsy, just like the evidence linking specific genes to high intelligence, violent aggression, homosexuality, bipolar disorder and countless other complex human traits and ailments. That was merely one in a string of reports in which the Times and other major media hyped what turned out to be erroneous claims linking complex traits and disorders—from homosexuality and high intelligence to schizophrenia and bipolar disorder—to specific genes. I thought those days were over, and that scientists and the media have learned to doubt extremely reductionist genetic accounts of complex traits and behaviors. I was wrong. Last Sunday, the “Opinion” section of the Times published an essay, “The Feel-Good Gene,” which states: “For the first time, scientists have demonstrated that a genetic variation in the brain makes some people inherently less anxious, and more able to forget fearful and unpleasant experiences. This lucky genetic mutation produces higher levels of anandamide–the so-called bliss molecule and our natural marijuana–in our brains. In short, some people are prone to be less anxious simply because they won the genetic sweepstakes and randomly got a genetic mutation that has nothing at all to do with strength of character.” This article, like the one touting the alcoholism gene 25 years ago, was written by a physician, Richard Friedman, professor of psychiatry at Weill Cornell Medical College. I emphasize this fact because scientific hype is often blamed on supposedly ignorant journalists like me rather than on physicians and other so-called experts. © 2015 Scientific American

Keyword: Drug Abuse; Genes & Behavior
Link ID: 20689 - Posted: 03.14.2015

By Maggie Fox Teenagers who use marijuana heavily grow up to have poor memories and also have brain abnormalities, a new study shows. The study cannot say which came first — the brain structure differences or the pot use. But it suggests there could be long-term effects of heavy marijuana use. A team at Northwestern University looked at 97 volunteers with and without mental illness. The dope smokers said they'd used marijuana daily starting at age 16 or 17, and said they had not used other drugs. The daily marijuana users had an abnormally shaped hippocampus and performed about 18 percent more poorly on long-term memory tasks, the researchers reported in the journal Hippocampus. The hippocampus is a part of the brain used in storing long-term memory. "The memory processes that appear to be affected by cannabis are ones that we use every day to solve common problems and to sustain our relationships with friends and family," said Dr. John Csernansky, who worked on the study. Previous research by the same Northwestern team showed heavy pot smokers had poor short-term and working memory and abnormally shaped brain structures including the striatum, globus pallidus and thalamus. "It is possible that the abnormal brain structures reveal a pre-existing vulnerability to marijuana abuse," Matthew Smith, who led the study, said in a statement.

Keyword: Drug Abuse; Learning & Memory
Link ID: 20687 - Posted: 03.14.2015