Chapter 4. The Chemistry of Behavior: Neurotransmitters and Neuropharmacology

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By Cathleen O’Grady People who take tiny amounts of LSD, “magic mushrooms,” and related drugs report a range of benefits, from more creativity to improved psychological well-being. But do these microdoses—typically less than 10% of the amount that causes a true psychedelic experience—actually benefit the mind? That’s been a hard question to answer. Placebo-controlled trials are tricky to pull off, because psychedelics are so tightly regulated. Now, researchers have come up with a creative workaround: They’ve enlisted microdosing enthusiasts to hide their drugs in gel capsules and mix them up with empty capsules. The upshot of this “self-blinding” study: Microdosing did lead to improvements in psychological well-being—but so did the placebo capsules. “The benefits are real,” says lead author Balázs Szigeti, a neuroscientist at Imperial College London. “But they are not caused by the pharmacological effects of microdosing.” The findings, however, are “the least interesting thing about this study,” says Noah Haber, a study design specialist at Stanford University. The “very, very clever” method of self-blinding pushes the boundaries of what can be investigated using randomized placebo controls, he says. Getting the new study off the ground wasn’t easy. Obtaining ethical approval to enroll psychedelic-taking volunteers was a “long and difficult process,” Szigeti says. And then he had to go out and find those volunteers, which he did by reaching out to microdosing communities, giving talks at psychedelic societies, and holding an “ask me anything” discussion on Reddit. Szigeti eventually garnered more than 1600 sign-ups, but once potential participants realized they’d have to procure their own psychedelics, interest ebbed, and only 246 ended up in the experiment. © 2021 American Association for the Advancement of Science.

Keyword: Depression; Drug Abuse
Link ID: 27721 - Posted: 03.06.2021

By Matt Richtel Texas has one of the most restrictive medical marijuana laws in the country, with sales allowed only by prescription for a handful of conditions. That hasn’t stopped Lukas Gilkey, chief executive of Hometown Hero CBD, based in Austin, Texas. His company sells joints, blunts, gummy bears, vaping devices and tinctures that offer a recreational high. In fact, business is booming online as well, where he sells to many people in other states with strict marijuana laws. But Mr. Gilkey says that he is no outlaw, and that he’s not selling marijuana, just a close relation. He’s offering products with a chemical compound — Delta-8-THC — extracted from hemp. It is only slightly chemically different from Delta 9, which is the main psychoactive ingredient in marijuana. And that small distinction, it turns out, may make a big difference in the eyes of the law. Under federal law, psychoactive Delta 9 is explicitly outlawed. But Delta-8-THC from hemp is not, a loophole that some entrepreneurs say allows them to sell it in many states where hemp possession is legal. The number of customers “coming into Delta 8 is staggering,” Mr. Gilkey said. “You have a drug that essentially gets you high, but is fully legal,” he added. “The whole thing is comical.” The rise of Delta 8 is a case study in how industrious cannabis entrepreneurs are pulling apart hemp and marijuana to create myriad new product lines with different marketing angles. They are building brands from a variety of potencies, flavors and strains of THC, the intoxicating substance in cannabis, and of CBD, the nonintoxicating compound that is often sold as a health product. With Delta 8, entrepreneurs also believe they have found a way to take advantage of the country’s fractured and convoluted laws on recreational marijuana use. It’s not quite that simple, though. Federal agencies, including the Drug Enforcement Administration, are still considering their options for enforcement and regulation. © 2021 The New York Times Company

Keyword: Drug Abuse
Link ID: 27714 - Posted: 02.28.2021

By Tom Bartlett The stimulant hexedrone — known more commonly as “bath salts” — is the kind of drug Carl Hart believes would be ideal to take right before a hellish academic reception or departmental holiday party. He’ll do cocaine and ecstasy from time to time and is a fan of the opioids oxycodone and morphine for the “pleasurable calmness” they induce. But after a long day, there are few things that Hart, a neuroscientist and psychology professor at Columbia University, enjoys more than a few lines of heroin by the fireplace. Hart has long pushed back against what he sees as the demonization of certain drugs and those who take them, particularly Black users, who are incarcerated at higher rates than white users. He has questioned the prevailing opinion that methamphetamine interferes with cognition and presented findings that suggest marijuana has minimal impact on the working memory of regular smokers. In his 2013 memoir, High Price: A Neuroscientist’s Journey of Self-Discovery That Challenges Everything You Know About Drugs and Society, Hart makes the case for decriminalizing narcotics and argues that “we’re too afraid of these drugs and of what we think they do.” In a 2014 talk at the TEDMed conference, he argued that “science should be driving our drug policy and our drug education, even if that makes you and me uncomfortable.” In his new book, Drug Use for Grown-Ups: Chasing Liberty in the Land of Fear, the former chairman of Columbia’s psychology department goes a step further, revealing that he has used — and continues to use — a number of illegal drugs. In fact, Hart recently said on a podcast that he was on methamphetamine when he delivered that TEDMed talk and that he’s given some of his best interviews the day after using heroin. Hart, who is 54, tried heroin for the first time in his 40s and has used it regularly — and responsibly, he contends — for years. “I am an unapologetic drug user,” he writes. “I take drugs as part of my pursuit of happiness, and they work. I am a happier and better person because of them.” He is not, he writes, an addict, and his book is not about addiction. Hart says that his stressful recent stint as department chairman was more damaging to his health than any substance he has ingested. © 2021 The Chronicle of Higher Education

Keyword: Drug Abuse
Link ID: 27709 - Posted: 02.28.2021

By Linda Searing People who smoke even occasionally are more likely than nonsmokers to have a serious type of stroke caused by a ruptured blood vessel — 27 percent more likely if they smoke up to 20 packs a year, according to research published in the journal Stroke. The average American smoker, according to the Centers for Disease Control and Prevention, smokes 14 cigarettes daily, which means about 255 packs a year. The type of stroke examined by the researchers, known as a subarachnoid hemorrhage, occurs when a weakened blood vessel ruptures and bleeds into the space between a person’s brain and skull. Most often, this results from an aneurysm, an abnormal bulge in a blood vessel. A subarachnoid hemorrhage is not as common as an ischemic stroke, which is caused by a blood clot, but it also can lead to neurological problems or be life-threatening without immediate treatment to stop the bleeding. To focus on the effect that smoking may have on people’s risk for this type of stroke, the researchers analyzed data on 408,609 adults, about a third of whom smoked regularly. During the study period, 904 participants had a subarachnoid hemorrhage. The more people smoked, the greater their risk for this type of stroke, prompting the American Stroke Association to note that the findings “provide evidence for a causal link” between smoking and subarachnoid hemorrhage. washingtonpost.com © 1996-2021

Keyword: Drug Abuse; Stroke
Link ID: 27707 - Posted: 02.28.2021

By Anahad O’Connor Five years ago, a group of nutrition scientists studied what Americans eat and reached a striking conclusion: More than half of all the calories that the average American consumes comes from ultra-processed foods, which they defined as “industrial formulations” that combine large amounts of sugar, salt, oils, fats and other additives. Highly processed foods continue to dominate the American diet, despite being linked to obesity, heart disease, Type 2 diabetes and other health problems. They are cheap and convenient, and engineered to taste good. They are aggressively marketed by the food industry. But a growing number of scientists say another reason these foods are so heavily consumed is that for many people they are not just tempting but addictive, a notion that has sparked controversy among researchers. Recently, the American Journal of Clinical Nutrition explored the science behind food addiction and whether ultra-processed foods might be contributing to overeating and obesity. It featured a debate between two of the leading experts on the subject, Ashley Gearhardt, associate professor in the psychology department at the University of Michigan, and Dr. Johannes Hebebrand, head of the department of child and adolescent psychiatry, psychosomatics and psychotherapy at the University of Duisburg-Essen in Germany. Dr. Gearhardt, a clinical psychologist, helped develop the Yale Food Addiction Scale, a survey that is used to determine whether a person shows signs of addictive behavior toward food. In one study involving more than 500 people, she and her colleagues found that certain foods were especially likely to elicit “addictive-like” eating behaviors, such as intense cravings, a loss of control, and an inability to cut back despite experiencing harmful consequences and a strong desire to stop eating them. At the top of the list were pizza, chocolate, potato chips, cookies, ice cream, French fries and cheeseburgers. © 2021 The New York Times Company

Keyword: Obesity; Drug Abuse
Link ID: 27706 - Posted: 02.23.2021

By Nicholas Bakalar A large analysis looked at hundreds of factors that may influence the risk of heart failure and found one dietary factor in particular that was associated with a lower risk: drinking coffee. Heart failure, sometimes called congestive heart failure, occurs when the heart muscle becomes weakened and can no longer pump blood efficiently. It can be caused by high blood pressure, heart valve disease, heart attack, diabetes and other diseases and conditions. The analysis included extensive, decades-long data from three large health studies with 21,361 participants, and used a method called machine learning that uses computers to find meaningful patterns in large amounts of data. “Usually, researchers pick things they suspect would be risk factors for heart failure — smoking, for example — and then look at smokers versus nonsmokers,” said the senior author, Dr. David P. Kao, an assistant professor of medicine at the University of Colorado. “But machine learning identifies variables that are predictive of either increased or decreased risk, but that you haven’t necessarily thought of.” Using this technique, Dr. Kao and his colleagues found 204 variables that are associated with the risk for heart failure. Then they looked at the 41 strongest factors, which included, among others, smoking, marital status, B.M.I., cholesterol, blood pressure and the consumption of various foods. The analysis is in Circulation: Heart Failure. In all three studies, coffee drinking was associated more strongly than any other dietary factor with a decreased long-term risk for heart failure. Drinking a cup a day or less had no effect, but two cups a day conferred a 31 percent reduced risk, and three cups or more reduced risk by 29 percent. There were not enough subjects who drank more than three cups daily to know if more coffee would decrease the risk further. © 2021 The New York Times Company

Keyword: Drug Abuse
Link ID: 27701 - Posted: 02.23.2021

By Warren Cornwall Prozac might need a new warning label: “Caution: This antidepressant may turn fish into zombies.” Researchers have found that long-term exposure to the drug makes guppies act more alike, wiping out some of the typical behavioral differences that distinguish them. That could be a big problem when the medication—technically named fluoxetine—washes into streams and rivers, potentially making fish populations more vulnerable to predators and other threats. In recent decades, scientists have uncovered a plethora of ways that pharmaceuticals affect animals in the lab and in the wild, such as by altering courtship, migration, and anxiety. The drugs find their way into the environment through water that pours from sewage treatment plants, which is rarely filtered to remove the chemicals. But the findings are usually based on an average taken from combining measurements of all the individual animals in a group. Giovanni Polverino, a behavioral ecologist at the University of Western Australia, Perth, and colleagues wondered whether this calculation obscured important but subtle insights about individual animals. Did the drug change behavior similarly in all the creatures in a group? Or were certain kinds of “personalities” affected more strongly? To find out, Polverino’s team captured 3600 guppies (Poecilia reticulata)—a common silvery fish often used in labs that grows to half the length of an average human’s pinkie—from a creek in northeastern Australia. In the laboratory, the fish and their offspring—as many as six generations—spent 2 years in tanks filled with either freshwater, water with fluoxetine at levels common in the wild, or a higher dose similar to places near sewage outflows. © 2021 American Association for the Advancement of Science.

Keyword: Depression; Neurotoxins
Link ID: 27685 - Posted: 02.13.2021

by Peter Hess A new engineered protein that glows in the presence of serotonin enables researchers to track the neurotransmitter’s levels and location in the brains of living mice, according to a new study. This ‘serotonin sensor’ could help elucidate serotonin’s role in autism, experts say. Serotonin helps regulate mood, circulation and digestion, among other functions. Some people with autism have elevated levels of serotonin in their blood. Other evidence links serotonin to social behavior in mice. “Serotonin is wildly important both for basic research and human health. And for the longest time, ways to measure it were very indirect,” says co-lead researcher Loren Looger, professor of neuroscience at the University of California, San Diego. “Only with sensors like this can one follow it in vivo, which is critical.” Unlike other tools for measuring serotonin, the sensor can also show changes in serotonin activity over time, making it an exciting tool for autism research, says Jeremy Veenstra-VanderWeele, professor of psychiatry at Columbia University, who was not involved in the study. “This tool will make it possible to understand the relationships between serotonin release and complex behaviors, including in different genetic mouse models related to autism,” he says. “I imagine that this tool will come into fairly broad use.” Programmable protein: The new sensor originated from one described last year that detects a different neurotransmitter, acetylcholine. Looger and his team used a computer algorithm to redesign the acetylcholine-binding portion of the sensor protein so that it could attach to serotonin instead. © 2021 Simons Foundation

Keyword: Depression; Obesity
Link ID: 27680 - Posted: 02.08.2021

Paul Tullis On a sunny day in London in 2015, Kirk Rutter rode the Tube to Hammersmith Hospital in hopes of finally putting an end to his depression. Rutter had lived with the condition off and on for years, but the burden had grown since the death of his mother in 2011, followed by a relationship break-up and a car accident the year after. It felt as if his brain was stuck on what he describes as “an automatic circuit”, repeating the same negative thoughts like a mantra: “‘Everything I do turns to crap.’ I actually believed that,” he recalls. The visit to Hammersmith was a preview. He would be returning the next day to participate in a study, taking a powerful hallucinogen under the guidance of Robin Carhart-Harris, a psychologist and neuroscientist at Imperial College London. Years of talking therapy and a variety of anti-anxiety medications had failed to improve Rutter’s condition, qualifying him for the trial. “Everyone was super nice, like really lovely, and especially Robin,” Rutter recalls. Carhart-Harris led him to a room with a magnetic resonance imaging (MRI) machine, so researchers could acquire a baseline of his brain activity. Then he showed Rutter where he would spend his time while on the drug. Carhart-Harris asked him to lie down and played him some of the music that would accompany the session. He explained that he would have on hand a drug that could neutralize the hallucinogen, if necessary. Then the two practised a grounding technique, to help calm Rutter in the event that he became overwhelmed. Without warning, Rutter burst into tears. “I think I knew this was going to be unpacking a lot — I was carrying a bit of a load at the time,” Rutter says. © 2021 Springer Nature Limited

Keyword: Depression; Drug Abuse
Link ID: 27670 - Posted: 01.30.2021

Research shows that hallucinogens can be highly effective treatments for anxiety, depression, addiction, and trauma. Here's everything you need to know: Aren't psychedelic drugs illegal? Under federal and most states' laws, they are, but a push to legalize or decriminalize the drugs is gaining momentum. On Election Day, Oregon voters made their state the first to legalize the active ingredient in "magic mushrooms" — psilocybin — for mental health therapy in a controlled setting with a therapist. Washington, D.C., voters passed Initiative 81, making the city at least the fifth to decriminalize magic mushrooms. Similar legislation has been proposed in California, Vermont, and Iowa. Last summer, Canada issued four terminally ill patients exemptions to take psilocybin for end-of-life anxiety and depression. British Columbia resident Mona Strelaeff, 67, got an exemption for treatment for trauma, addiction, depression, and anxiety. "All the unresolved trauma," Strelaeff said, "it came back and I was beyond terrified, shaking uncontrollably, and crying." She said that psilocybin therapy helped her conquer "those tough memories" and today she "ain't afraid of jack (s---)." How does psychedelic therapy work? Participants usually take psilocybin or LSD in a relaxing setting, lying down with blindfolds and headphones on, listening to music. Trained supervisors encourage them to "go inward and to kind of experience whatever is going to come up," said Alan Davis, who studies psychedelics at Johns Hopkins University. Bad psilocybin trips are rare — Johns Hopkins and NYU researchers conducted 500 sessions without observing any "serious adverse effects" — but they can occur. Advocates say careful dose control, supervision, and controlled settings are very important. Psilocybin sessions typically last between four and six hours, while LSD sessions go on for 12. Robin Carhart-Harris, who runs the Centre for Psychedelic Research at Imperial College in London, theorized that such sessions can "reboot" the brain in a way similar to a near-death or intense spiritual experience. ® 2021 The Week Publications Inc.,

Keyword: Depression; Drug Abuse
Link ID: 27667 - Posted: 01.27.2021

By Linda Searing A surge in the number of U.S. residents who have died of a drug overdose — 81,230 in the 12 months ending last May — set a record for the most such deaths in a one-year span, according to a report issued by the Centers for Disease Control and Prevention. Overall, drug overdose deaths jumped by 18 percent from the previous year, with increases recorded in 46 states (by more than 20 percent in 25 of those states) and just four states recording a decrease. Deaths attributed to synthetic opioids, mainly fentanyl, increased 38 percent nationwide, but 98 percent in 10 western states. Overdose deaths tied to cocaine use, often involving co-use or mixing with fentanyl or heroin, increased about 26 percent, and deaths linked to psychostimulants, such as methamphetamine, increased 35 percent. The CDC noted that the death rate from drug overdoses accelerated as the coronavirus pandemic set in, disrupting daily life and leading to isolation, depression, anxiety and economic distress for many, including people with a substance use disorder. In a health alert, the CDC urged broader distribution and use of naloxone, a medication that can block the effects of an overdose, as well as expanded prevention and treatment for those struggling with drug use. A free and confidential hotline, offering information and treatment referral, can be reached by calling the Substance Abuse and Mental Health Services Administration at 800-662-4357.

Keyword: Drug Abuse
Link ID: 27663 - Posted: 01.27.2021

By Katherine J. Wu For a lesson in euphoria, look no further than a house cat twined around a twig of silver vine. When offered a snipping of the plant, which contains chemicals similar to the ones found in catnip, most domesticated felines will purr, drool and smoosh their faces into its intoxicating leaves and stems, then zonk out in a state of catatonic bliss. But the ecstatic rush might not be the only reason felines flock to these plants, new research suggests. Compounds laced into plants like silver vine and catnip might also help cats ward off mosquitoes, equipping them with a DIY pest repellent that’s far more fun to apply than a greasy coat of DEET. Other papers have pointed to the insect-deterring effects of catnip and similar plants. But the new study, published Wednesday in the journal Science Advances, is the first to draw a direct link between the plants and their protective effects on cats. “It’s a really interesting observation, that such a well-known behavior could be having this unappreciated benefit for cats,” said Laura Duvall, a mosquito researcher at Columbia University in New York who wasn’t involved in the study. Botanically speaking, catnip and silver vine are distant cousins. But both contain iridoids, a suite of chemicals that seem to potently tickle pleasure circuits in cats. To pinpoint the evolutionary roots of this plant-feline connection, a team of researchers led by Masao Miyazaki, a biochemist and veterinary scientist at Iwate University in Japan, corralled a menagerie of cats — some domestic, some wild — and monitored their responses to an iridoid extracted from silver vine, which thrives in many mountainous parts of Asia. Presented with scraps of paper dosed with iridoid, most of the cats initiated a ritualized rolling and rubbing. Some cats were so eager to engage with the compounds that they climbed up the sides of their cages — some of which were nearly four feet tall — to anoint themselves with chemical-soaked paper secured to the ceiling. © 2021 The New York Times Company

Keyword: Drug Abuse
Link ID: 27662 - Posted: 01.23.2021

Kayt Sukel Psychedelic drugs conjure images of tie-dyed tee shirts, Woodstock, and Vietnam War protests. While early research into the properties of drugs like psilocybin (magic mushrooms) and lysergic acid diethylamide (LSD) during the middle of the 20th century suggested therapeutic potential for diverse mental health conditions, their role in the 1960s anti-war and counterculture movement made them suspect by law enforcement. Not long after American psychologist Timothy Leary called for people to “turn on, tune in, and drop out,” endorsing the regular use of psychedelic drugs for health and well-being, the federal Controlled Substances Act classified them as highly dangerous Schedule 1 compounds, or drugs with “no currently accepted medical use and a high potential for abuse.” “Initially, psychedelics showed quite a lot of promise for treating a wide range of mental health conditions—in particular, addiction and post-traumatic stress disorder (PTSD),” says Anil Seth, co-director of the Sackler Centre for Consciousness Science at the University of Sussex in the United Kingdom. “There’s long been a blame game going regarding what led to these drugs being outlawed, mostly focusing on people like Timothy Leary promoting indiscriminate use of what we know are quite powerful drugs. But the end result was that, despite their promise, it became nearly impossible for anyone to do any research at all on them.” Over the past decade, however, there has been a revival of psychopharmacology and neuroscience research into the effects of psychedelic drugs. In fact, despite continuing legal barriers and funding challenges involved with using these banned drugs in research studies—many researchers wait years for Food and Drug Administration approvals and require funding from non-governmental agencies to move forward—several unique research centers, including the Centre for Psychedelic Research at Imperial College London and Johns Hopkins University’s Center for Psychedelics and Consciousness Research, are now actively studying LSD, psilocybin, and dimethyltryptamine (DMT), from both basic science and clinical perspectives. © 2021 The Dana Foundation

Keyword: Depression; Drug Abuse
Link ID: 27646 - Posted: 01.15.2021

Jon Hamilton Root extracts from the African shrub iboga have long been used in traditional healing rituals and more recently as an experimental treatment for depression and to reduce drug cravings in addiction. Scientists now are working on a version of the extract that doesn't cause heart attacks or hallucinations as side effects. Steeve Jordan/AFP via Getty Images A chemically tweaked version of the psychedelic drug ibogaine appears to relieve depression and addiction symptoms without producing hallucinations or other dangerous side effects. The results of a study in rodents suggest it may be possible to make psychedelic drugs safe enough to become mainstream treatments for psychiatric disorders, the authors report Wednesday in the journal Nature. "What we need is a medicine that is so safe that you can take it home and put it in your medicine cabinet just like you would aspirin," says David Olson, the paper's senior author and an assistant professor at the University of California, Davis. "And that's really what we were trying to achieve." The success with ibogaine is "a promising first step," says Gabriela Manzano, a postdoctoral fellow at Weill Cornell Medicine in New York and a co-author of a commentary on the study. "This provides a road map on how we could start tweaking these chemical compounds to make them very useful in the clinic," she says. "Keep the good parts, get rid of the bad parts." For decades, psychedelic drugs, including ketamine and psilocybin, have shown promise in treating people with mental health problems including addiction, depression and post-traumatic stress disorder. But doctors and researchers have been wary of using the drugs because of their side effects. © 2020 npr

Keyword: Drug Abuse; Depression
Link ID: 27621 - Posted: 12.12.2020

by Josh Wilbur Jake Haendel was a hard-partying chef from a sleepy region of Massachusetts. When he was 28, his heroin addiction resulted in catastrophic brain damage and very nearly killed him. In a matter of months, Jake’s existence became reduced to a voice in his head. Jake’s parents had divorced when he was young. He grew up between their two homes in a couple of small towns just beyond reach of Boston, little more than strip malls, ailing churches and half-empty sports bars. His mother died of breast cancer when he was 19. By then, he had already been selling marijuana and abusing OxyContin, an opioid, for years. “Like a lot of kids at my school, I fell in love with oxy. If I was out to dinner with my family at a restaurant, I would go to the bathroom just to get a fix,” he said. He started culinary school, where he continued to experiment with opioids and cocaine. He hid his drug use from family and friends behind a sociable, fun-loving front. Inside, he felt anxious and empty. “I numbed myself with partying,” he said. After culinary school, he took a job as a chef at a local country club. At 25, Jake tried heroin for the first time, with a co-worker (narcotics are notoriously prevalent in American kitchens). By the summer of 2013, Jake was struggling to find prescription opioids. For months, he had been fending off the symptoms of opioid withdrawal, which he likened to “a severe case of the flu with an added feeling of impending doom”. Heroin offered a euphoric high, staving off the intense nausea and shaking chills of withdrawal. Despite his worsening addiction, Jake married his girlfriend, Ellen, in late 2016. Early in their relationship, Ellen had asked him if he was using heroin. He had lied without hesitation, but she soon found out the truth, and within months, the marriage was falling apart. “I was out of control, selling lots of heroin, using even more, spending a ridiculous amount of money on drugs and alcohol,” he said. In May 2017, Ellen noticed that he was talking funnily, his words slurred and off-pitch. “What’s up with your voice?” she asked him repeatedly.

Keyword: Consciousness; Drug Abuse
Link ID: 27595 - Posted: 11.27.2020

By Bethany Brookshire A hungry brain craves food. A lonely brain craves people. After spending a day completely isolated from anyone else, people’s brains perked up at the sight of social gatherings, like a hungry person’s brain seeing food, scientists report November 23 in Nature Neuroscience. Cognitive neuroscientist Livia Tomova, then at MIT, and her colleagues had 40 participants fast for 10 hours. At the end of the day, certain nerve cells in the midbrain fired up in response to pictures of pizza and chocolate cake. Those neurons — in the substantia nigra pars compacta and ventral tegmental area — produce dopamine, a chemical messenger associated with reward (SN: 8/27/15). On a different day, the same people underwent 10 hours of isolation (no friends, no Facebook and no Instagram). That evening, neurons in the same spot activated in response to pictures of people chatting or playing team sports. The more hunger or isolation the subject reported, the stronger the effect (SN: 10/4/17). In people who reported that they were generally more lonely, the social responses were blunted. “We don’t really know what causes that,” Tomova says. “Maybe being isolated doesn’t really affect them as much, because it’s something that is not that different, perhaps, from their everyday life.” The midbrain, which plays an important role in people’s motivation to seek food, friends, gambling or drugs, responds to food and social signals even when people aren’t hungry or lonely. After all, a person always could eat or hang out. But hunger and loneliness increased the reaction and made people’s responses specific to the thing they were missing. The findings “speak to our current state,” says Tomova, now at the University of Cambridge. COVID-19 has left many more socially isolated, putting mental as well as physical health at stake (SN: 3/29/20) and leaving people with cravings for more than food. “It’s important to look at the social dimension of this kind of crisis.” L. Tomova et al. Acute social isolation evokes midbrain craving responses similar to hunger. Nature Neuroscience. Published online November 23, 2020. doi: 10.1038/s41593-020-00742-z. = © Society for Science & the Public 2000–2020

Keyword: Stress; Obesity
Link ID: 27594 - Posted: 11.27.2020

By Katherine J. Wu For a rodent that resembles the love child of a skunk and a steel wool brush, the African crested rat carries itself with a surprising amount of swagger. The rats “very much have the personality of something that knows it’s poisonous,” says Sara Weinstein, a biologist at the University of Utah and the Smithsonian Conservation Biology Institute who studies them. In sharp contrast to most of their skittish rodent kin, Lophiomys imhausi lumber about with the languidness of porcupines. When cornered, they fluff up the fur along their backs into a tip-frosted mohawk, revealing rows of black-and-white bands that run like racing stripes down their flanks — and, at their center, a thicket of specialized brown hairs with a honeycomb-like texture. Those spongy hairs contain a poison powerful enough to bring an elephant to its knees, and are central to Dr. Weinstein’s recent research, which confirmed ideas about how this rat makes itself so deadly. Give them a chance and African crested rats will take nibbles from the branch of a poison arrow tree. It’s not for nutrition. Instead, they will chew chunks of the plants and spit them back out into their fur, anointing themselves with a form of chemical armor that most likely protects them from predators like hyenas and wild dogs. The ritual transforms the rats into the world’s only known toxic rodents, and ranks them among the few mammals that borrow poisons from plants. Dr. Weinstein’s research, which was published last week in the Journal of Mammalogy, is not the first to document the crested rats’ bizarre behavior. But the new paper adds weight to an idea described nearly a decade ago, and offers an early glimpse into the animals’ social lives. First documented in the scientific literature in 1867, the rarely-glimpsed African crested rat “has captured so much interest for so long,” said Kwasi Wrensford, a behavioral ecologist at the University of California, Berkeley who wasn’t involved in the study. “We’re now just starting to unpack what makes this animal tick.” © 2020 The New York Times Company

Keyword: Neurotoxins; Learning & Memory
Link ID: 27592 - Posted: 11.27.2020

By Abby Goodnough PHILADELPHIA — Steven Kelty had been addicted to crack cocaine for 32 years when he tried a different kind of treatment last year, one so basic in concept that he was skeptical. He would come to a clinic twice a week to provide a urine sample, and if it was free of drugs, he would get to draw a slip of paper out of a fishbowl. Half contained encouraging messages — typically, “Good job!” — but the other half were vouchers for prizes worth between $1 and $100. “I’ve been to a lot of rehabs, and there were no incentives except for the idea of being clean after you finished,” said Mr. Kelty, 61, of Winfield, Pa. “Some of us need something to motivate us — even if it’s a small thing — to live a better life.” The treatment is called contingency management, because the rewards are contingent on staying abstinent. A number of clinical trials have found it highly effective in getting people addicted to stimulants like cocaine and methamphetamine to stay in treatment and to stop using the drugs. But outside the research arena and the Department of Veterans Affairs, where Mr. Kelty is a patient, it is nearly impossible to find programs that offer such treatment — even as overdose deaths involving meth, in particular, have soared. There were more than 16,500 such deaths last year, according to preliminary data, more than twice as many as in 2016. Early data suggests that overdoses have increased even more during the coronavirus pandemic, which has forced most treatment programs to move online. Researchers say that one of the biggest obstacles to contingency management is a moral objection to the idea of rewarding someone for staying off drugs. That is one reason publicly funded programs like Medicaid, which provides health coverage for the poor, do not cover the treatment. Some treatment providers are also wary of giving prizes that they say patients could sell or trade for drugs. Greg Delaney, a pastor and the outreach coordinator at Woodhaven, a residential treatment center in Ohio, said, “Until you’re at the point where you can say, ‘I can make a good decision with this $50,’ it’s counterproductive.” © 2020 The New York Times Company

Keyword: Drug Abuse; Learning & Memory
Link ID: 27556 - Posted: 10.28.2020

R. Douglas Fields As I opened my copy of Science at home one night, an unfamiliar word in the title of a new study caught my eye: dopaminylation. The term refers to the brain chemical dopamine’s ability, in addition to transmitting signals across synapses, to enter a cell’s nucleus and control specific genes. As I read the paper, I realized that it completely upends our understanding of genetics and drug addiction. The intense craving for addictive drugs like alcohol and cocaine may be caused by dopamine controlling genes that alter the brain circuitry underlying addiction. Intriguingly, the results also suggest an answer to why drugs that treat major depression must typically be taken for weeks before they’re effective. I was shocked by the dramatic discovery, but to really understand it, I first had to unlearn some things. “Half of what you learned in college is wrong,” my biology professor, David Lange, once said. “Problem is, we don’t know which half.” How right he was. I was taught to scoff at Jean-Baptiste Lamarck and his theory that traits acquired through life experience could be passed on to the next generation. The silly traditional example is the mama giraffe stretching her neck to reach food high in trees, resulting in baby giraffes with extra-long necks. Then biologists discovered we really can inherit traits our parents acquired in life, without any change to the DNA sequence of our genes. It’s all thanks to a process called epigenetics — a form of gene expression that can be inherited but isn’t actually part of the genetic code. This is where it turns out that brain chemicals like dopamine play a role. All genetic information is encoded in the DNA sequence of our genes, and traits are passed on in the random swapping of genes between egg and sperm that sparks a new life. Genetic information and instructions are coded in a sequence of four different molecules (nucleotides abbreviated A, T, G and C) on the long double-helix strand of DNA. The linear code is quite lengthy (about 6 feet long per human cell), so it’s stored neatly wound around protein bobbins, similar to how magnetic tape is wound around spools in cassette tapes. All Rights Reserved © 2020

Keyword: Drug Abuse; Epigenetics
Link ID: 27555 - Posted: 10.28.2020

By Jane E. Brody Do you have the heart to safely smoke pot? Maybe not, a growing body of medical reports suggests. Currently, increased smoking of marijuana in public, even in cities like New York where recreational use remains illegal (though no longer prosecuted), has reinforced a popular belief that this practice is safe, even health-promoting. “Many people think that they have a free pass to smoke marijuana,” Dr. Salomeh Keyhani, professor of medicine at the University of California, San Francisco, told me. “I even heard a suggestion on public radio that tobacco companies should switch to marijuana because then they’d be selling life instead of selling death.” But if you already are a regular user of recreational marijuana or about to become one, it would be wise to consider medical evidence that contradicts this view, especially for people with underlying cardiovascular diseases. Well: Get the best of Well, with the latest on health, fitness and nutrition. Compared with tobacco, marijuana smoking causes a fivefold greater impairment of the blood’s oxygen-carrying capacity, Dr. Keyhani and colleagues reported. In a review of medical evidence, published in January in the Journal of the American College of Cardiology, researchers described a broad range of risks to the heart and blood vessels associated with the use of marijuana. The authors, led by Dr. Muthiah Vaduganathan, cardiologist at Brigham and Women’s Hospital in Boston, point out that “marijuana is becoming increasingly potent, and smoking marijuana carries many of the same cardiovascular health hazards as smoking tobacco.” Edible forms of marijuana have also been implicated as a possible cause of a heart attack, especially when high doses of the active ingredient THC are consumed. © 2020 The New York Times Company

Keyword: Drug Abuse
Link ID: 27550 - Posted: 10.26.2020