Genetics researchers have confirmed that people with a different form of a certain gene are more susceptible to drug and alcohol addiction. They hope the finding will help predict who might get hooked and what treatments will help those who do. Researchers led by Wolfgang Sadee, a scientist at the Ohio State University, have figured out how differences in one gene can make the brain more sensitive to alcohol, narcotics, or nicotine. The gene Sadee's team looked at has long been known to code for a kind of brain protein called an opioid receptor, which acts like a switch, turning on pleasure and blocking pain when triggered by certain addictive drugs. The surfaces of our brain cells are covered by different kinds of receptor proteins. These receptors act as chemical docking stations that allow individual brain cells to communicate with each other by sending and receiving small bursts of chemicals. Each type of receptor can only be activated by a certain class of chemicals, which makes the communication between brain cells specific and meaningful. However receptors can also respond to chemicals in the brain environment not sent by other cells, like things that we've ingested such as alcohol or particles from cigarette smoke. The mu-opioid receptor that Sadee's team looked at is the primary target for morphine, but it also plays a large part in responses to alcohol, nicotine, and narcotics such as cocaine. © ScienCentral, 2000-2007.

Keyword: Drug Abuse; Genes & Behavior
Link ID: 10328 - Posted: 06.24.2010

Linda Geddes Could magnets make the mind grow stronger? In mice at least, stimulating the brain with a magnetic coil appears to promote the growth of new neurons in areas associated with learning and memory. If the effect is confirmed in humans, it might open up new ways of treating age-related memory decline and diseases like Alzheimer's. Transcranial magnetic stimulation (TMS) has been used experimentally to treat a range of brain disorders, including depression and schizophrenia, and to rehabilitate people after a stroke. TMS uses a magnetic coil to induce electric fields in the brain tissue - activating or deactivating groups of neurons, although the exact mechanism has remained unknown. One theory was that it aided learning and memory by strengthening brain circuits through a process called long-term potentiation (LTP). To investigate, Fortunato Battaglia at the City University of New York and his colleagues gave mice TMS for five days, then analysed their brains for evidence of LTP or cell proliferation. They confirmed that TMS enhanced LTP in all areas of the brain tested, by modifying key glutamate receptors so that they stayed active for longer. The team also saw large increases in the proliferation of stem cells in the dentate gyrus hippocampus. These cells divide throughout life and are now believed to play a crucial role in memory and mood regulation (See "Memories are made of this?"). © Copyright Reed Business Information Ltd.

Keyword: Learning & Memory
Link ID: 10327 - Posted: 06.24.2010

It's a scenario straight out of Gray's Anatomy – a paramedic or doctor plops a mask over the face of a person struggling to breathe and begins dispensing pure oxygen. Yet growing research suggests that inhaling straight oxygen can actually harm the brain. For the first time, a new UCLA brain-imaging study reveals why. Published in the May 22 edition of Public Library of Science (PLoS) Medicine, the findings fly in the face of national guidelines for medical practice and recommend a new approach adding carbon dioxide to the gas mix to preserve brain function in patients. "For decades, the medical community has championed 100 percent oxygen as the gold standard for resuscitation. But no one has reported what happens inside our brains when we inhale pure oxygen," explained Ronald Harper, distinguished professor of neurobiology at the David Geffen School of Medicine at UCLA. "What we discovered adds to a compelling body of evidence for modifying a widely practiced standard of care in the United States." Harper's team used functional magnetic resonance imaging (fMRI) to capture detailed pictures of what occurs inside the human brain during two different breathing scenarios. The technique detects subtle increases in blood flow triggered by the activation of different parts of the brain, causing these regions to glow or "light up" on the color scan.

Keyword: Stroke
Link ID: 10326 - Posted: 06.24.2010

COLUMBUS, Ohio – Imagine if a naturally occurring chemical in your body could help make you feel more calm and relaxed – but it would only work during the long days of summer. The same chemical would, instead, make you aggressive and nasty when you were exposed to less daylight during the winter. That's exactly what occurs for a specific species of mouse, according to a new study at Ohio State University, published online this week in the Proceedings of the National Academy of Sciences. Researchers found that the class of hormones called estrogens acts to increase aggression in the Oldfield Mouse (Peromyscus polionotus) during the short days of winter. However, when daylight increases in the summer, estrogen decreases aggression among male Oldfield mice, a species commonly found in the southeastern United States. The finding is significant because it is one of the first studies to show how a very simple environmental factor – in this case, the length of daylight – can have a powerful effect on how genes influence behavior, at least in some species. "We found that estrogen has totally opposite effects on behavior in these mice depending only on how much light they got each day," said Brian Trainor, co-author of the study and postdoctoral fellow in psychology and neuroscience at Ohio State University.

Keyword: Aggression; Genes & Behavior
Link ID: 10325 - Posted: 06.24.2010

Roxanne Khamsi A drug which reduces the desire for marijuana and blocks its effect on the brain has been successfully tested in rats. Scientists say the findings may translate into better therapies for cannabis addiction in humans. Rodents given a compound derived from a plant in the buttercup family lose their hankering for a synthetic version of tetrahydrocannabinol (THC) - the active compound in marijuana. The treatment also blocked a reward response in the animals' brains when they did receive synthetic THC. In the first part of the experiment, Steven Goldberg at the National Institute on Drug Abuse in Maryland, US, and his colleagues placed rats in a cage with a lever the animals could push. Each time the rats leaned on the lever, they received a dose of the synthetic THC through a small tube running into their body. Over a period of three weeks the rats learned to enjoy the effects of synthetic THC and frequently self-administered the drug. By comparison, rats that received saline solution did not press the lever often. Goldberg's team then injected the rats with a compound derived from the seeds of the Delphinium brownii plant, which is in the buttercup family. The compound, known as methyllycaconitine (MLA), had a dramatic effect on the animals' behaviour. Journal reference: Journal of Neuroscience (DOI: 10.1523/JNEUROSCI.0027-07.2007) © Copyright Reed Business Information Ltd.

Keyword: Drug Abuse
Link ID: 10324 - Posted: 06.24.2010

Catherine Brahic And then there were four... Here's the scenario: three sharks are in a tank, all three are female and all were captured when they were sexually immature babies. They spend three years in the tank together without ever coming in contact with a male. Then, one day, a baby shark pops up. The sharks are hammerheads, living in an aquarium at Omaha's Henry Doorly Zoo, in the US. The pup was born on 14 December 2001, and triggered a great deal of confusion, which has only now finally been cleared up: the pup was the result of a "virgin birth". For many years, different theories were argued over. Perhaps one of the females had been inseminated by a shark from another species? Or maybe she had been inseminated before she was captured? Female sharks do have an organ that allows them to store sperm, but a three-year storage would have been unprecedented. What is more, sex between sharks tends to be rather rough and females are usually left with marks as a result of this. But none of the three females from Florida Keys had any marks on them when they were captured. Still, the insemination theory was considered "because it was even more difficult to imagine asexual reproduction in a shark," says Paulo Prodöhl of Queen's University Belfast in Northern Ireland. Journal reference: Biology Letters (DOI: 10.1098/rsbl.2007.0189) © Copyright Reed Business Information Ltd.

Keyword: Sexual Behavior
Link ID: 10323 - Posted: 06.24.2010

NEW YORK (Reuters Health) - In older people with mild cognitive impairment, having a drink now and then -- up to an average of one drink of alcohol each day -- may delay progression to dementia, new research suggests. "While many studies have assessed alcohol consumption and cognitive function in the elderly, this is the first study to look at how alcohol consumption affects the rate of progression of mild cognitive impairment to dementia," study authors Dr. Vincenzo Solfrizzi and Dr. Francesco Panza, from the University of Bari in Italy, said in a statement. In the study, reported in the medical journal Neurology, the researchers assessed the occurrence of mild cognitive impairment in 1445 subjects and the progression to dementia in 121 patients with mild cognitive impairment. The participants were between 65 and 84 years of age at the start of the study, and they were followed for 3.5 years. Alcohol use was assessed starting the year before the survey. Drinking was not associated the development of mild cognitive impairment, according to the report. However, once mild impairment occurred, subjects who had up to one drink per day of alcohol had an 85 percent reduced risk of dementia compared with those who abstained. SOURCE: Neurology, May 22, 2007. © 1996-2007 Scientific American, Inc.

Keyword: Alzheimers; Drug Abuse
Link ID: 10322 - Posted: 06.24.2010

By Laura Sessions Stepp This just in, from a global study on sexual well-being released last month: More than half of Americans are unhappy with their sex lives. Or are they? Last year, another international survey reported that more than two out of three are quite satisfied. So it goes in the relatively new world of research on sexual satisfaction. For all that we know now about the problems associated with sex -- HIV/AIDS, erectile dysfunction and unwanted pregnancies, to name three -- we understand very little about how sex contributes to our quality of life. What is the connection between sex and emotions? How important is sex to happiness? Sixty years after Indiana University professor Alfred Kinsey made sexuality a topic for serious study, we are still groping in the dark when it comes to how much we enjoy it. There are reasons for this. Religious leaders who founded this country viewed sex primarily as a means of procreation, not pleasure, and wanted it confined it to marriage -- the latter belief still championed in some quarters. © 2007 The Washington Post Company

Keyword: Sexual Behavior
Link ID: 10321 - Posted: 06.24.2010

Jerry Fodor Consciousness is all the rage just now. It boasts new journals of its very own, from which learned articles overflow. Neuropsychologists snap its picture (in colour) with fMRI machines, and probe with needles for its seat in the brain. At all seasons, and on many continents, interdisciplinary conferences about consciousness draw together bizarre motleys that include philosophers, psychologists, phenomenologists, brain scientists, MDs, computer scientists, the Dalai Lama, novelists, neurologists, graphic artists, priests, gurus and (always) people who used to do physics. Institutes of consciousness studies are bountifully subsidised. Meticulous distinctions are drawn between the merely conscious and the consciously available; and between each of these and the preconscious, the unconscious, the subconscious, the informationally encapsulated and the introspectable. There is no end of consciousness gossip on Tuesdays in the science section of the New York Times. Periodically, Nobel laureates pronounce on the connections between consciousness and evolution, quantum mechanics, information theory, complexity theory, chaos theory and the activity of neural nets. Everybody gives lectures about consciousness to everybody else. But for all that, nothing has been ascertained with respect to the problem that everybody worries about most: what philosophers have come to call ‘the hard problem’. The hard problem is this: it is widely supposed that the world is made entirely of mere matter, but how could mere matter be conscious? How, in particular, could a couple of pounds of grey tissue have experiences? © LRB Ltd, 1997-2007

Keyword: Miscellaneous
Link ID: 10320 - Posted: 06.24.2010

By JANE E. BRODY Anyone who has flown across several time zones for business or pleasure has no doubt experienced jet lag — that days-long feeling that all body functions are out of sync with the new environment. And as soon as you become adjusted, you return home and have to go through it again. It’s enough to prompt some people to stay home. Fighting Jet Lab This is especially true for older people, who may finally have the time and money to travel far and wide but find themselves even more bothered by jet lag than when they were young. I just went through the jet lag experience twice, when I flew from New York to Australia and back to New York three weeks later. And I’m writing this column the morning after arriving in California for a grandson’s birthday. Though I was sleepy by 8 p.m., I went to bed on California time, 11 p.m., but awoke at 2:30 a.m., which in New York is 5:30 a.m., when I normally wake up at home. I forced myself to go back to sleep for another hour and a half, but then my unadjusted body clock beckoned me to get up and start my day. Sleep is not the only function affected by jet lag. The digestive tract is off schedule, too. You become hungry at all the wrong times and may have trouble with waste disposal. Less obvious are the disrupted daily shifts in core body temperature and hormone secretions, which are no longer in tune with the day and night in the new environment. Copyright 2007 The New York Times Company

Keyword: Biological Rhythms
Link ID: 10319 - Posted: 06.24.2010

By Erik Stokstad All across the world, people are polluting waterways with estrogen. Excreted in urine, the hormone passes through most wastewater plants and ends up in streams and lakes, where some studies suggest it is feminizing male fish. Now a large experiment has shown that even a very low level of estrogen in a lake can cause enough reproductive harm to wipe out an entire population of minnows in 2 years. Extra estrogen isn't good for male fish. Laboratory studies have shown that chronic exposure to low doses causes males to produce eggs in their testes and takes away their secondary sex characteristics, such as darker coloration and tubercules on their noses. The big question was what those levels mean for populations in the wild. To find out, researchers led by Karen Kidd of the University of New Brunswick, Canada, performed an experiment in a lake in western Ontario. Each summer for 3 years, they spiked the lake with a few parts per trillion of 17á-ethynylestradiol--the active ingredient in birth-control pills--in concentrations like those found in streams and lakes elsewhere. The experiment took place in a remote area set aside for research. Within weeks of the first doses, male minnows started making vitellogenin, a protein that helps eggs mature in females. They wound up with levels 8000 to 10,000 times normal. (Females increased production to 8 to 80 times their usual levels, and the estrogen somehow slowed egg development.) Sexual development was delayed in the males, and fewer and fewer fish were found; apparently, the fish had stopped reproducing. After the second year, the researchers couldn't find any fathead minnow nests. "We didn't expect to see such a dramatic and quick response," Kidd says. It took more than 2 years after researchers stopped adding estrogen for the population to begin to recover. © 2007 American Association for the Advancement of Science.

Keyword: Sexual Behavior; Hormones & Behavior
Link ID: 10318 - Posted: 06.24.2010

Michael Reilly A new way of monitoring brain activity can help predict a clinically depressed patient's response to a drug, leading to more effective treatment. Drug treatments for the disease take an average of six to eight weeks to start working. But side effects like headache, dizziness and nausea often begin immediately, making patients feel worse long before they begin feeling better. For this reason some quit their medication within three to four weeks. Now a team of researchers has shown that a technique called frontal quantitative electroencephalography (fqEEG) can help predict whether a drug will work. The test can be used effectively just a week after a patient begins taking the medication. The researchers used an array of five electrodes placed across the forehead to measure the electrical activity in the frontal lobes of 111 patients who had been on the antidepressant drug Lexapro (escitalopram) for a week. Patients displaying low levels of activity were considered likely to respond to the drug and were kept on Lexapro for six more weeks. Those with higher levels of activity were thought unlikely to respond, and were chosen at random to either switch to Wellbutrin (bupropion), or stay on Lexapro despite the fqEEG's readings. © Copyright Reed Business Information Ltd.

Keyword: Depression
Link ID: 10317 - Posted: 06.24.2010

Heidi Ledford It's a safe bet that most people who take sildenafil — better known under its commercial name, Viagra — aren't looking for a good night's rest. But it turns out that the 'little blue pill' commonly used to treat erectile dysfunction is also good for relieving some forms of jetlag. Well, at least in hamsters. Diego Golombek and his colleagues at the National University of Quilmes in Buenos Aires, Argentina, injected hamsters with sildenafil and then pushed the animals' light/dark schedule ahead by six hours, roughly the equivalent of putting them on a plane from New York to Paris. Hamsters who'd had a dose of sildenafil adjusted their busy wheel-running schedules to the new light regime 50% faster, the team reports in Proceedings of the National Academy of Sciences1. Although the results seem to provide relief to jetsetting hamsters, whether sildenafil will have the same effect in humans remains to be seen. If the drug does work in humans, it could be easier to use than melatonin, a hormone used to overcome jetlag that requires several doses to have a significant effect. Golombek's hamsters only needed a single dose of sildenafil to accelerate their adjustment to new time zones. But the drug was administered by injection and it isn't yet known whether taking one of those little blue pills will have the same effect. ©2007 Nature Publishing Group

Keyword: Biological Rhythms; Sexual Behavior
Link ID: 10316 - Posted: 06.24.2010

Jennifer Viegas, Discovery News — With the male grunting and the female emitting loud and long operatic calls, mating chacma baboons produce an incredible amount of noise. And a new study has found that other males take advantage of the din by eavesdropping on mating couples to determine the status of relationships. If the couple quarrels or parts, for even just a brief moment, the snooping male then takes advantage of the situation by mating with the female, himself. "For male baboons, copulation calls are the most interesting vocalizations because they are only given by females and are clearly associated with females mating," lead author Catherine Crockford told Discovery News. Crockford, a researcher in the University of Pennsylvania’s Department of Psychology, explained that eavesdropping sometimes provides low-status male baboons with such mating opportunities, since higher-ranked, more dominant males otherwise monopolize high-ranked females. High-status baboons form what are known as consortships, which can last for a few hours up to a week. During this mini marriage-like period, the male follows a female closely and guards her against other approaching males. © 2007 Discovery Communications Inc.

Keyword: Sexual Behavior
Link ID: 10315 - Posted: 06.24.2010

Steroid use may be more than twice as common as official figures suggest, a leading expert has told the BBC. According to the British Crime Survey there are 42,000 regular anabolic steroid users in the UK. Drugs expert Jim McVeigh said there could be as many as 100,000. "Basically we're looking at numbers being on a par with heroin users," he added. One treatment centre in Merseyside reports that steroid use has rocketed in the last three years. Staff now treat four new steroid users for every new heroin user - a reversal of the situation in 2004. There is a particular problem with users aged under 25. Nurse Deborah Jones, who works at the harm reduction centre in Wirral, says steroid use has increased particularly among the under 25s. Mr McVeigh, of Liverpool John Moores University, insists the problem is hidden because people do not admit to using steroids. "At any one time in Liverpool there are approximately 1,000 anabolic steroid users - nationally we're looking at over 100,000," he told BBC Radio Five Live. Every month, the Wirral centre sees about 21 users aged under 25, and the youngest patient is just 16. Ms Jones says the use among younger people is growing as more and more strive for the "perfect body". "It's all about being big, muscular, toned, and they can gain that much quicker using steroids than they ever can working out," she says. "It does take over. They want to have the rippling six pack with the golden body, but most of them end up as the Arnold Schwarzenegger - that's what they see as success." (C)BBC

Keyword: Drug Abuse; Hormones & Behavior
Link ID: 10314 - Posted: 05.22.2007

How much money would it take to get you to stick a pin into your palm? How much to stick a pin into the palm of a child you don’t know? How much to slap a friend in the face (with his or her permission) as part of a comedy skit? Well, what about slapping you father (with his permission) as part of a skit? How you answer questions such as these may reveal something about your morality, and even your politics—conservatives, for example, tend to care more about issues of hierarchy and respect, while liberals concentrate on caring and fairness. (You can take a short test of your moral intuitions by visiting www.yourmorals.org). In a review to be published in the May 18 issue of the journal Science, Jonathan Haidt, associate professor of psychology at the University of Virginia, discusses a new consensus scientists are reaching on the origins and mechanisms of morality. Haidt shows how evolutionary, neurological and social-psychological insights are being synthesized in support of three principles: 1) Intuitive primacy, which says that human emotions and gut feelings generally drive our moral judgments; 2) Moral thinking if for social doing, which says that we engage in moral reasoning not to figure out the truth, but to persuade other people of our virtue or to influence them to support us; and 3) Morality binds and builds, which says that morality and gossip were crucial for the evolution of human ultrasociality, which allows humans – but no other primates – to live in large and highly cooperative groups.

Keyword: Emotions
Link ID: 10313 - Posted: 06.24.2010

Bruce Bower Flies aren't deep thinkers. Yet these humble creatures display a penchant for spontaneous behavior that represents an evolutionary building block of voluntary choice, also known as free will, a controversial new study suggests. By mathematically analyzing flight maneuvers, a team of scientists showed for the first time that fruit flies move in a way that is neither wholly random nor predetermined. An evolved brain mechanism in the fly must generate spontaneous, unpredictable flight shifts to aid in vital tasks such as avoiding predators and tracking potential mates, conclude neuroscientist Björn Brembs of the Free University of Berlin and his colleagues. "Our results provide strong evidence that the exact prediction of an individual [fly]'s behavior is impossible," Brembs says. This finding dovetails with other evidence that people must have a neural ability to generate spontaneous behavior. Without such an ability, "it's hard to imagine people having access to free will," he adds. The researchers reject the traditional assumption that flies and other animals search for food and engage in other critical behaviors primarily by using their senses to glean clues from their surroundings. Instead, the new results suggest that circuitous foraging routes and other behavioral signatures of flies arise spontaneously, although sensory clues may also play a role. Brembs' team describes its findings in the May PLoS ONE. ©2007 Science Service

Keyword: Miscellaneous
Link ID: 10312 - Posted: 06.24.2010

Lauran Neergaard, Associated Press — Can you get smarter than a fifth-grader? Of course, but new research suggests some of the brain's basic building blocks for learning are nearing adult levels by age 11 or 12. It is the first finding from a study of how children's brains grow. The most interesting results are yet to come. About 500 super-healthy newborns to teenagers, recruited from super-healthy families, are having periodic MRI scans of their brains as they grow up. They also get a battery of age-appropriate tests of such abilities as IQ, language skills and memory. The project, funded by the National Institutes of Health, is tricky work. Move during an MRI, and the image blurs. Because scientists cannot sedate healthy children, they are having to get crafty to keep their subjects still. Tired toddlers are put in the scanners at naptime; mom squeezes in for a cuddle and earplugs help block the machines' noisy banging. Six-year-olds wear earphones and watch favorite videos beamed into the scanner. The MRI images measure how different parts of the brain grow and reorganize throughout childhood. © 2007 Discovery Communications Inc.

Keyword: Development of the Brain
Link ID: 10311 - Posted: 06.24.2010

Roxanne Khamsi Disney's Nemo spoke in English, but real clownfish also communicate in a unique way, research reveals. High-speed video imaging and X-ray technology show that clownfish clack their jaws together to produce warning sounds before they attack. This is the first time that fish have been shown to communicate in this way, the researchers say. Scientists have known for nearly 80 years that clownfish produced a swift succession of clacking noises when they spot an intruder in their territory or want to attract a potential mate (listen to the clownfish warning noise). "It is like someone knocking on a door," describes Eric Parmentier at the University of Liege in Belgium, who studies fish behaviour. Clownfish generate about five clicking sounds per second when communicating, but exactly how they produce the noises has been a mystery. Parmentier and colleagues used high-speed video to record and analyse the body movements of Amphiprion clarkii clownfish. © Copyright Reed Business Information Ltd.

Keyword: Animal Communication; Aggression
Link ID: 10310 - Posted: 06.24.2010

Alan I. Leshner People are fascinated by the brain, in large part because of a great interest in understanding their own minds and mental health. Over a century of neuroscience and psychological research has convinced most people that "Descartes died," leaving the old mind/brain dualism behind. The reality that we don't have a mind separate from the rest of our body has been brought home in many experimental ways, perhaps especially by modern neuroimaging techniques that allow investigators to look into the brains of living, awake, and behaving human beings--watching minds in action. That the brain is the seat of the mind does not necessarily mean that a purely reductionist approach will, in the long run, fully explain the workings of the mind. In fact, there is no evidence that we will be able to understand all aspects of the mind simply in molecular neurobiological terms. At the same time, a purely "up-uctionist" approach won't meet the need either. We can't understand the mind through working only at the behavioral level. Instead, we will need both biological and behavioral research, separately and in combination. Great progress has been made in the past decade in neuroscience, behavioral science, and behavioral neuroscience, and we now have the scientific sophistication to make even more rapid advances in understanding the brain and mind. Neuroscience is among the fastest-growing disciplines of biology and has shown extraordinary recent productivity. Indeed, we have probably learned more about the brain in the past 20 years than in all of recorded history. © 2007 American Association for the Advancement of Science

Keyword: Miscellaneous
Link ID: 10309 - Posted: 06.24.2010