By Susan Gaidos Mention hypnosis, and the image that springs to mind is a caped magician swinging a pocket watch, seducing otherwise sensible people into barking like dogs. But hypnosis is more than a stage show act. For years, psychologists have used it to help patients calm preflight jitters, get a good night’s sleep or chuck a cigarette habit. Hypnosis even has uses in mainstream medicine for reducing the side effects of cancer treatments and helping patients cope with pain. Some physicians routinely employ hypnosis as an adjunct to mainstream anesthesia to help block pain during surgery or childbirth. Most recently, hypnosis has advanced from stage and clinic into the laboratory. It is now used as a research tool to temporarily create hallucinations, compulsions, delusions and certain types of seizures in the lab so that these phenomena can be investigated in detail. Such studies may lead to more effective treatments for a number of psychiatric and neurological disorders, assert psychologists Peter W. Halligan and David Oakley in the June issue of Trends in Cognitive Sciences. Other scientists, intrigued by the many practical uses of hypnosis, are striving to figure out how it works. Using the latest neuroimaging tools, these scientists are getting a look at what goes on in the hypnotized brain. The findings are mesmerizing. © Society for Science & the Public 2000 - 2009

Keyword: Pain & Touch; Attention
Link ID: 13296 - Posted: 06.24.2010

By Cassandra Willyard Each fall, hundreds of millions of newly hatched monarch butterflies flit from the fields and forests in eastern regions of Canada and the United States to the alpine fir forests of central Mexico, converging on the same spot to wait out the winter. Scientists don't know exactly how these insects find their way, but a new study shows that, to navigate, the butterflies rely on biological clocks. Oddly enough, the clocks are located in their antennae, not in their brains as previously thought. Migrating monarchs rely on the sun to maintain a constant heading. Because the sun drifts from east to west as the day wears on, the butterflies need a timekeeping device to help them compensate for its movement. Monarchs have a biological clock in their brains that relies on light cues to regulate their sleep-wake cycles and monitor day length. Scientists assumed they also used this clock to navigate. But the new study shows that the antennae possess a separate clock that controls time compensation. "That was a huge surprise," says Steven Reppert, a neurobiologist at the University of Massachusetts Medical School in Worcester and co-author of the new study. Reppert and his colleagues began studying antennae because they thought the appendages might assist migration in other ways--by allowing the butterflies to pick up certain scents, for example. They soon saw something surprising. When they clipped the antennae off about 30 migrating monarchs and put them in a flight simulator, which can track the direction they try to fly, the butterflies were disoriented. Whereas butterflies with antenna flew south to southeast, those with clipped antennae flew in random directions, although each individual hewed to its heading fairly consistently. © 2009 American Association for the Advancement of Science

Keyword: Biological Rhythms; Animal Migration
Link ID: 13295 - Posted: 06.24.2010

IT HAS long been a puzzle that girls who grow up without their fathers at home reach sexual maturity earlier than girls whose fathers live with them. For years, absent fathers have taken the blame for this, because growing up quickly has negative consequences for girls. For example, early-bloomers are more likely to suffer depression, hate their bodies, engage in risky sex and get pregnant in their teen years. It could be a simple matter of not having as many eyes, particularly suspicious fatherly ones, watching over daughters. Or it could be a complicated physiological response to stress, in which girls adapt their reproductive strategy to their circumstances. If life is harsh, the theory goes, maybe they need to get their babies into the world as quickly as possible. The animal world suggests that the effect is not restricted to humans. Young mice, pigs, goats and even a few primates get signals from their kin which inhibit sexual development; a strange male in their midst, by contrast, really speeds things up. Research in humans has shown that girls growing up with stepfathers mature even more quickly than fatherless girls and that stepbrothers have a measurable effect too. However, Jane Mendle of the University of Oregon and her colleagues have suggested another putative cause: genes. Specifically, the same genes that might make a dad more likely to leave his family could be behind early sexual development as well. The researchers came to their conclusion after analysing data collected through the American National Longitudinal Survey of Youth. Dr Mendle looked at 1,382 boys and girls, each of whom was related to at least one other subject through their mother. Most of the mothers were pairs of sisters, but some were identical twins or first cousins raised as sisters. © The Economist Newspaper Limited 2009.

Keyword: Sexual Behavior; Genes & Behavior
Link ID: 13294 - Posted: 06.24.2010

In 2006, concern over the welfare of his family caused Dario Ringach to stop using animals in his research. A neuroscientist at the University of California in Los Angeles (UCLA), Ringach had been receiving threats from animal-rights extremists over his experiments involving primates. Then, an undetonated firebomb was left next door to the house of a colleague, apparently because the activists had the wrong address. After three years of keeping a low profile, Ringach is now trying to raise public support for the use of animals in research. This month, he published a commentary on the subject in the Journal of Neuroscience1 and a letter to the editor in the Journal of Neurophysiology2 in which he calls on scientists to publicly support such research. His coauthor on both was David Jentsch, a neuropsychopharmacologist at UCLA whose work involves primates and whose car was firebombed earlier this year. Nature spoke with Ringach about his concerns. You say that animal-rights extremists are winning. Why? You can see this in a recent Pew research survey on public opinion on science. Only 52% of the broad public supports biomedical research involving animals. And over the years, this has consistently declined. What is behind this trend? A lot of organizations at different levels have had a tremendous impact — from work that the Humane Society of the United States [based in Washington DC] has been doing in exposing failures in the food industry, to work that PETA [People for the Ethical Treatment of Animals, based in London] is doing in trying to reach out to children very early. © 2009 Nature Publishing Group

Keyword: Animal Rights
Link ID: 13293 - Posted: 06.24.2010

By Katherine Ellison For decades, attention-deficit hyperactivity disorder has sparked debate. Is it a biological illness, the dangerous legacy of genes or environmental toxins, or a mere alibi for bratty kids, incompetent parents and a fraying social fabric? With 4.5 million U.S. children having received a diagnosis of the disorder -- and more than half of them taking prescription drugs to control it -- the question has divided doctors and patients, parents and teachers, and mothers and fathers. Scientists maintain that they've been narrowing in on the origins and mechanics of disabling distraction, while gathering increasing evidence that ADHD is as real as such less controversial disorders as Down syndrome and schizophrenia. Their most recent progress is described in a Sept. 9 report in the Journal of the American Medical Association, based on a new study that indicates a striking difference in the brain's motivational machinery in people with ADHD symptoms. "This is another big piece in the puzzle saying that there is something there, that this is not simply a matter of anxious parents," said James Swanson, a co-author of the report and a developmental psychologist based at the University of California at Irvine. The JAMA study said that, compared with a group of healthy subjects, brain scans of 53 adults with ADHD revealed a flaw in the way they process dopamine, which among other things, alerts people to new information and helps them anticipate pleasure and rewards. Swanson speculated that people with ADHD may even have a net deficit of dopamine. © 2009 The Washington Post Company

Keyword: ADHD; Brain imaging
Link ID: 13292 - Posted: 06.24.2010

By Katherine Harmon dementia alzheimer's money financial managementPaying bills or counting change may seem like basic life skills to most, but for those who are about to slip into older-age dementia, the tasks can become increasingly difficult. And as fiscal functionality begins to fail, Alzheimer's disease might be less than a year away, a new study suggests. "Impairments in financial skills and judgments are often the first functional changes demonstrated by patients with incipient dementia," wrote the authors of the paper, which was published online today in Neurology. Although the relationship between money management skills and dementia has been established for some time, the researchers' focus on declining skills as an early indicator showed that once these abilities start to slip, the diagnosable disease is likely not far behind. Researchers from the University of Alabama at Birmingham gave 163 older adults—76 of whom were deemed healthy and 87 of whom were diagnosed as being mildly cognitively impaired (MCI)—a financial exam, which included exercises such as paying for groceries and making investment decisions. They found that those subjects who were already slightly impaired performed more poorly on aspects of the test, such as checkbook use, than the control group. © 1996-2009 Scientific American Inc.

Keyword: Alzheimers
Link ID: 13291 - Posted: 06.24.2010

by Andy Coghlan Crazy as it sounds, alcohol may one day be given to people with brain injuries to help them recover. The idea has arisen from a study of 38,000 people with head injuries, which found that those with alcohol in their blood were more likely to survive. For every 100 people who died when stone-cold sober, only 88 died with ethanol – the kind of alcohol in drinks – in their veins. "The finding raises the intriguing possibility that administering ethanol to patients with brain injuries may improve outcome," conclude the investigators. Lead researcher Ali Salim of the Cedars-Sinai Medical Center in Los Angeles said he hoped a trial could be mounted, but more information is needed first. "We need a better understanding of the exact mechanism, the appropriate dose and specific timing of treatment before we can embark on clinical trials," he told New Scientist. Salim said that several previous studies have found similar beneficial effects – although others do not. Animal experiments, meanwhile, suggest that relatively low doses of alcohol protect the brain from injury, but high doses increase the risk of death. More research is also needed to establish how alcohol protects the brain, but Salim says it may work by blunting the amount of adrenalin reaching the brain, which reduces inflammation. © Copyright Reed Business Information Ltd

Keyword: Brain Injury/Concussion; Drug Abuse
Link ID: 13290 - Posted: 06.24.2010

By Greg Miller Boozing it up in adolescence contributes to risky behavior in adulthood, according to a new study with rats. Some researchers suspect that the same is true for people, but they've had a hard time establishing whether adolescent drinking makes people prone to risk-taking or whether risk-prone people are simply more likely to start drinking as teenagers. Although the new work doesn't settle the issue, it bolsters the case that early alcohol use can cause lasting changes in behavior. Some of the best data available show that people who start drinking as adolescents and drink more heavily then are more likely to have problems with alcohol and drug abuse later in life, says Ilene Bernstein, a neuroscientist at the University of Washington, Seattle, and the senior author of the new study. But those studies have fallen short of determining cause and effect, Bernstein says. To get around this pitfall, she and her colleagues turned to rats, assigning individuals from a genetically identical strain to either drinking or teetotaling groups. Although rats don't voluntarily like to drink alcohol, the researchers found they could entice the rodents with spiked gelatin--the murine equivalent of the Jell-O shots beloved by college students everywhere. Adolescent rats assigned to the drinking group had access to the stuff for 20 days. They consumed the equivalent of "multiple, multiple drinks" a day but spread their drinking over many hours and never appeared visibly drunk, Bernstein says. © 2009 American Association for the Advancement of Science.

Keyword: Drug Abuse; Development of the Brain
Link ID: 13289 - Posted: 06.24.2010

by Jessica Hamzelou It's a dieter's dream: imagine that your appetite simply reduced, making it easy for you to eat less, but your body continued to burn the amount of calories it burned when you were eating normally, allowing you to keep the weight off. That is what has happened to a group of mice genetically engineered to limit the action of a gene called Cpe. Their metabolism remained high despite being less hungry and not eating as much as normal mice. If the corresponding gene in humans could one day be targeted by drugs, it might allow dieters to keep burning calories at the same rate as they do when eating normally. Crash dieting causes the hypothalamus in the brain to slow the body's metabolism and store energy more efficiently. Not only does this make it tricky to shift the weight, but it also primes the body to start laying down fat. This process means that the pounds are piled back on as soon as normal eating resumes . Leona Plum of the Naomi Berrie Diabetes Center at Columbia University's Medical Center and her team identified a protein in this brain region in mice called Fox01, which controls a gene, Cpe, which is known to make mice susceptible to obesity. The team genetically engineered mice lacking this protein. "Interrupting the link between the protein and Cpe caused a different breakdown of neuropeptides – brain chemicals - in the hypothalamus, which made the mice less hungry," says Plum. © Copyright Reed Business Information Ltd.

Keyword: Obesity; Genes & Behavior
Link ID: 13288 - Posted: 06.24.2010

By NATASHA SINGER HOW can you get a faster high from sustained-release pain pills like OxyContin? Let me count some of the ways. People have crushed them using bookends, hammers, mortars and pestles, and then snorted the powder, according to doctors who study addiction. They’ve chewed and swallowed fistfuls of pills. They’ve minced the pills in blenders, pulverized them in coffee grinders, dissolved them in water and then injected the liquid. Even for those of us who don’t inhale, the misuse and abuse of prescription painkillers called opioids should matter because, putting moral and ethics aside for the moment, it’s costing us billions of dollars. In a 2008 federal survey, an estimated 4.7 million Americans were found to have used prescription pain relievers for nonmedical reasons in the previous month. The abuse of opioids now costs at least $11 billion annually in excess medical care including overdoses by adults and accidental ingestion by children, said Howard G. Birnbaum, a health economist with the Analysis Group in Boston. Corporate America loves a void, and now some pharmaceutical companies are developing innovative opioids intended to deter tampering and meet the market’s need. Some pills under development are rubberlike and harder to crush. Others contain ingredients that cause unpleasant reactions in the body, like flushing or itching, if the pill is adulterated. Taking a cue from exploding ink packets that can render stolen money unusable, some pills have an outer opioid layer and an inner core that, if tampered with, releases a drug that counters the high of the pain reliever. Copyright 2009 The New York Times Company

Keyword: Drug Abuse; Pain & Touch
Link ID: 13287 - Posted: 06.24.2010

By Carolyn Y. Johnson It started as a simple term project for an MIT class on ethics and law on the electronic frontier. Two students partnered up to take on the latest Internet fad: the online social networks that were exploding into the mainstream. With people signing up in droves to reconnect with classmates and old crushes from high school, and even becoming online “friends” with their family members, the two wondered what the online masses were unknowingly telling the world about themselves. The pair weren’t interested in the embarrassing photos or overripe profiles that attract so much consternation from parents and potential employers. Instead, they wondered whether the basic currency of interactions on a social network - the simple act of “friending” someone online - might reveal something a person might rather keep hidden. Using data from the social network Facebook, they made a striking discovery: just by looking at a person’s online friends, they could predict whether the person was gay. They did this with a software program that looked at the gender and sexuality of a person’s friends and, using statistical analysis, made a prediction. The two students had no way of checking all of their predictions, but based on their own knowledge outside the Facebook world, their computer program appeared quite accurate for men, they said. People may be effectively “outing” themselves just by the virtual company they keep. “When they first did it, it was absolutely striking - we said, ‘Oh my God - you can actually put some computation behind that,’ ” said Hal Abelson, a computer science professor at MIT who co-taught the course. © Copyright 2009 Globe Newspaper Company.

Keyword: Sexual Behavior
Link ID: 13286 - Posted: 06.24.2010

Patients with severe brain damage who do not appear to have signs of consciousness still seem able to learn, a Cambridge University study suggests. Researchers tested for Pavlovian-like responses in 22 people in a persistent vegetative state by playing a noise prior to a puff of air to the eye. Some subjects learnt to anticipate the puff of air causing the eye muscles to twitch, Nature Neuroscience reported. The team hopes it may lead to tests to determine which patients could recover. Study leader Dr Tristan Bekinschtein from the University of Cambridge said the consensus had been that learning to link one stimulus with another - in this case a noise and a puff of air - was dependent on explicit awareness of the association. But the study, where up to 70 puffs of air were delivered over a 25 minute period, showed that this sort of conditioning is possible even in patients who, by all other measures, are not conscious. Electrodes positioned by the eyes picked up whether the muscles began to respond or not. And a control experiment doing the same tests on people under general anaesthesia did not produce the same responses, suggesting that the learning does not happen when truly unconscious, and that some patients may have some level of consciousness not apparent on traditional tests. Dr Bekinschtein, who began the work as a PhD student in Argentina, said they also found that patients who started to anticipate the puff of air were more likely to show signs of recovery later on, in terms of increased ability to communicate. Although the results are reported in 22 patients, some of whom were in what is termed a "minimally conscious state", the team has since used the test in many more and is planning a large clinical trial with colleagues in the US and Belgium. (C)BBC

Keyword: Attention; Learning & Memory
Link ID: 13285 - Posted: 09.21.2009

Ian Sample, science correspondent People who are left wheelchair-bound by spinal cord injuries could regain some of their mobility through a rehabilitation programme being developed by scientists. Guardian neuroscience stories have found that a combination of drugs, muscle stimulation and treadmill exercises helps paralysed rats to recover the ability to walk normally. The animal tests pave the way for clinical trials in humans, which scientists hope to begin in the US and Switzerland within five years. The treatment, developed by neurologists at the University of Zurich and the University of California in Los Angeles, taps into neural circuits in the spinal cord that control the muscles used for walking. In able-bodied people, these "walking circuits" spring into action when they receive a signal from the brain, but if the spinal cord is damaged, the message from the brain never arrives. When contact with the brain is lost, the circuits shut down. "We've known for more than a century that there are networks of neurons in the spinal cord that generate the rhythmic activity needed for walking," said Grégoire Courtine at the Experimental Neurorehabilitation laboratory in Zurich. "Our study suggests that the brain mostly sends a go or no-go signal." A team led by Courtine used drugs known as serotonin agonists to awaken the walking circuits in paralysed rats whose spines had been severed. The researchers then used tiny electrodes to stimulate the animals' spinal circuitry, according to a report in the journal Nature Neuroscience. © Guardian News and Media Limited 2009

Keyword: Regeneration
Link ID: 13284 - Posted: 06.24.2010

By BILL FINLEY Martha Maxine might seem like an ill-fitting name for a 5-year-old male horse, but there is an explanation. He used to be a she. Martha Maxine will be a favorite in Saturday’s Tony Maurello Stakes. He won the filly division last year. Martha Maxine will be among the favorites Saturday in the $125,000 Tony Maurello Stakes at Balmoral Park outside Chicago, the same harness racing track where he won the filly division of the same race a year ago. He will make his fourth start since tests determined the horse was intersex, with male sex chromosomes. Complicated questions about possible intersex athletes have come up in human sports, including one recently in track and field, but those athletes typically have an opportunity to challenge any findings. In the case of Martha Maxine, the harness racing authorities took conclusive action. In June, the horse was reclassified as a male by the United States Trotting Association and barred from female-only races. The trainer and co-owner Erv Miller never suspected there was anything different about Martha Maxine; the horse had an uneventful but productive 2008 campaign. Still officially a female, Martha Maxine won 13 races last year, earning $193,891. “The only thing I ever noticed was that she was a very muscular mare,” Miller said. “She carried a lot of muscle tone, like a male does. Other than that, there was nothing different about her. When you think you’ve seen everything in this business, something else comes along. That’s what happened here.” Copyright 2009 The New York Times Company

Keyword: Sexual Behavior; Hormones & Behavior
Link ID: 13283 - Posted: 06.24.2010

By Alexis Madrigal Email Author Neuroscientist Craig Bennett purchased a whole Atlantic salmon, took it to a lab at Dartmouth, and put it into an fMRI machine used to study the brain. The beautiful fish was to be the lab’s test object as they worked out some new methods. So, as the fish sat in the scanner, they showed it “a series of photographs depicting human individuals in social situations.” To maintain the rigor of the protocol (and perhaps because it was hilarious), the salmon, just like a human test subject, “was asked to determine what emotion the individual in the photo must have been experiencing.” The salmon, as Bennett’s poster on the test dryly notes, “was not alive at the time of scanning.” methodsIf that were all that had occurred, the salmon scanning would simply live on in Dartmouth lore as a “crowning achievement in terms of ridiculous objects to scan.” But the fish had a surprise in store. When they got around to analyzing the voxel (think: 3-D or “volumetric” pixel) data, the voxels representing the area where the salmon’s tiny brain sat showed evidence of activity. In the fMRI scan, it looked like the dead salmon was actually thinking about the pictures it had been shown. “By complete, random chance, we found some voxels that were significant that just happened to be in the fish’s brain,” Bennett said. “And if I were a ridiculous researcher, I’d say, ‘A dead salmon perceiving humans can tell their emotional state.’” © 2009 Condé Nast Digital.

Keyword: Brain imaging
Link ID: 13282 - Posted: 06.24.2010

By Tina Hesman Saey Two male squirrel monkeys now see the world in a whole new way — in full color. Female squirrel monkeys can see in color, but male squirrel monkeys are normally red-green colorblind because they lack pigments in the retina that detect those wavelengths of light. Now, researchers have performed gene therapy that allowed two male squirrel monkeys named Sam and Dalton to produce proteins that detect red light. As soon as the red-light-harvesting protein was made in the monkeys’ eyes, the animals were able to discriminate between red and green spots in color vision tests, Jay Neitz of the University of Washington in Seattle and his collaborators report online September 17 in Nature. The experiment wasn’t supposed to work, Neitz says. People born with cataracts don’t develop nerve connections that help the brain make sense of messages sent by the eye. If the defect isn’t corrected early, these people remain essentially blind even if their eyes return to full function later. Because there was no reason to assume color vision was different from other types of vision, the team had assumed it would not be possible to reverse the deficit in an adult animal. Neitz polled experts in the vision field on whether they thought producing photoreceptors in colorblind adult monkeys could give color vision. “Every single person said, ‘absolutely not.’” But the researchers decided to move forward with the experiment to see if they could get the pigment protein to be made in the eye. © Society for Science & the Public 2000 - 2009

Keyword: Vision; Genes & Behavior
Link ID: 13281 - Posted: 06.24.2010

Young children's exposure to lead in the environment is harming their intellectual and emotional development, according to UK researchers. The researchers say the toxic effects of lead on the central nervous system are obvious even below the current so-called safe level of lead in the blood. They are recommending the threshold should be halved. A spokesman for the Health Protection Agency said levels of exposure should be kept to the minimum. Lead has been removed from paint and petrol by law in the UK, but it is still widespread in the environment. The study from the University of Bristol Centre for Child and Adolescent Health set out to see if there was any effect on the behaviour and intellectual development of children who had ingested just below the so-called safe level of 10 microgrammes per decilitre (or tenth of a litre) of blood. The study is published in the journal, Archives of Diseases in Childhood. The Bristol researchers took blood samples from 582 children at the age of 30 months. They found 27% of the children had lead levels above five microgrammes per decilitre. They followed the children's progress at regular intervals and then assessed their academic performance and behavioural patterns when they were seven to eight years old. After taking account of factors likely to influence the results, they found that blood lead levels at 30 months showed significant associations with educational achievement, antisocial behaviour and hyperactivity scores five years later. With lead levels up to five microgrammes per decilitre, there was no obvious effect. But lead levels between five and 10 microgrammes per decilitre were associated with significantly poorer scores for reading ( 49% lower) and writing (51% lower). A doubling in lead blood levels to 10 microgrammes per decilitre was associated with a drop of a third of a grade in their Scholastic Assessment Tests (SATs). And above 10 microgrammes per decilitre children were almost three times as likely to display antisocial behaviour patterns and be hyperactive than the children with the lower levels of lead in their blood. (C)BBC

Keyword: Development of the Brain; Neurotoxins
Link ID: 13280 - Posted: 09.17.2009

by Nora Schultz, Berlin NEUROSCIENCE could do for schools what biomedical research has done for healthcare. That's the conclusion of the Decade of the Mind (DOM) symposium last week in Berlin, Germany, to discuss how the latest findings could be used to improve education. "In medicine, we have an excellent system in place to go from basic research to clinical practice, while in neuroscience we have the basic understanding of how the brain learns but still need to figure out how to translate this into the classroom," says Manfred Spitzer of the University of Ulm in Germany, one of the conference organisers. With brain imaging and, increasingly, genetic studies now complementing psychology research, a host of new findings could inform teachers about the conditions in which our brains can be primed to learn best. One of the main themes emerging at the DOM meeting was that the foundation of successful learning is improving executive function - a collection of cognitive processes important for self-control and focusing on the task at hand. Brain-imaging studies have mapped executive function to several regions, including the anterior cingulate gyrus, which also lights up during error detection and when children learn numeracy and literacy. Various studies presented at the meeting showed that improving a child's executive function could be achieved with relatively small changes, for example, by altering the timetabling of exercise sessions or encouraging the learning of a musical instrument (see "Stretch and learn" and "The Stephen King effect") Improving a child's ability to focus on the task at hand can be achieved with relatively small changes © Copyright Reed Business Information Ltd

Keyword: Learning & Memory; Development of the Brain
Link ID: 13279 - Posted: 06.24.2010

By Jesse Bering It’s my impression that many straight people believe that there are two types of gay men in this world: those who like to give, and those who like to receive. No, I’m not referring to the relative generosity or gift-giving habits of homosexuals. Not exactly, anyway. Rather, the distinction concerns gay men’s sexual role preferences when it comes to the act of anal intercourse. But like most aspects of human sexuality , it’s not quite that simple. I’m very much aware that some readers may think that this type of article does not belong on this website. But the great thing about good science is that it’s amoral, objective and doesn’t cater to the court of public opinion. Data don’t cringe; people do. Whether we’re talking about a penis in a vagina or one in an anus, it’s human behavior all the same. The ubiquity of homosexual behavior alone makes it fascinating. What’s more, the study of self-labels in gay men has considerable applied value, such as its possible predictive capacity in tracking risky sexual behaviors and safe sex practices. People who derive more pleasure (or perhaps suffer less anxiety or discomfort) from acting as the insertive partner are referred to colloquially as “tops,” whereas those who have a clear preference for serving as the receptive partner are commonly known as “bottoms.” There are plenty of other descriptive slang terms for this gay male dichotomy as well, some repeatable (“pitchers vs. catchers,” “active vs. passive,” “dominant vs. submissive”) and others not—well, not for Scientific American , anyway. © 1996-2009 Scientific American Inc.

Keyword: Sexual Behavior
Link ID: 13278 - Posted: 06.24.2010

By C. CLAIBORNE RAY Q. Is addiction to nicotine stronger than addiction to cocaine? A. The two addictions are believed to involve similar brain pathways, and craving for both drugs has been found in one study to be reduced by mecamylamine, a drug used to block the rewarding effects of nicotine. But a 2006 study in the journal Addiction by Jack E. Henningfield, a researcher for the National Institute on Drug Abuse, examined the strength of the addictions on several measures and concluded that nicotine addiction could not be considered stronger than cocaine addiction. All drugs of abuse stimulate the release of the neurotransmitter dopamine. This is believed to be involved in producing feelings of pleasure and reward, and eventually in cravings for the drug when it is withdrawn. Nicotine, like cocaine, activates nerve cells in the brain’s mesolimbic system that contain dopamine. In the study comparing addictions to the two, the researchers considered several lines of evidence — including patterns of use, mortality and potential for physical dependence — and found that while both are highly addicting drugs, current evidence does not show nicotine to be more addicting than cocaine. For both, the study said, patterns of use and dependence are strongly influenced by factors like availability, price, regulations and social pressures, as well as pharmacological characteristics. Copyright 2009 The New York Times Company

Keyword: Drug Abuse
Link ID: 13277 - Posted: 06.24.2010