By RICHARD A. FRIEDMAN, M.D. “I’ve grown up on medication,” my patient Julie told me recently. “I don’t have a sense of who I really am without it.” At 31, she had been on one antidepressant or another nearly continuously since she was 14. There was little question that she had very serious depression and had survived several suicide attempts. In fact, she credited the medication with saving her life. But now she was raising an equally fundamental question: how the drugs might have affected her psychological development and core identity. It was not an issue I had seriously considered before. Most of my patients, who are adults, developed their psychiatric problems after they had a pretty clear idea of who they were as individuals. During treatment, most of them could tell me whether they were back to their normal baseline. Julie could certainly remember what depression felt like, but she could not recall feeling well except during her long treatment with antidepressant medications. And since she had not grown up before getting depressed, she could not gauge the hypothetical effects of antidepressants on her emotional and psychological development. Copyright 2008 The New York Times Company

Keyword: Depression; Development of the Brain
Link ID: 11525 - Posted: 06.24.2010

Using a rodent model of epilepsy, researchers found one of the body’s own neurotransmitters released during seizures, glutamate, turns on a signaling pathway in the brain that increases production of a protein that could reduce medication entry into the brain. Researchers say this may explain why approximately 30 percent of patients with epilepsy do not respond to antiepileptic medications. The study, conducted by researchers at the National Institute of Environmental Health Sciences (NIEHS), part of the National Institutes of Health, and the University of Minnesota College of Pharmacy and Medical School, in collaboration with Heidrun Potschka’s laboratory at Ludwig-Maximilians-University in Munich, Germany, is available online and will appear in the May 2008, issue of Molecular Pharmacology. "Our work identifies the mechanism by which seizures increase production of a drug transport protein in the blood brain barrier, known as P-glycoprotein, and suggests new therapeutic targets that could reduce resistance," said David Miller, Ph.D., a principal investigator in the NIEHS Laboratory of Pharmacology and co-author on the paper. The blood-brain barrier (BBB), which resides in brain capillaries, is a limiting factor in treatment of many central nervous system disorders. It is altered in epilepsy so that it no longer permits free passage of administered antiepileptic drugs into the brain. Miller explained that P-glycoprotein forms a functional barrier in the BBB that protects the brain by limiting access of foreign chemicals.

Keyword: Epilepsy
Link ID: 11524 - Posted: 06.24.2010

Jennifer Viegas -- Female Barbary macaques emit ear-piercing calls when mating, and now researchers have determined other males listen to these sounds with apparent interest. Since the female calls vary, depending on whether or not the male partner has successfully mated, it's believed the eavesdropping males use the sounds to figure out what's going on "in the bedroom" and may even rate the happenings. "The fact that copulation calls are loud and distinctive gives other males of the group the chance to listen in and 'judge' copulations," lead author Dana Pfefferle told Discovery News. Pfefferle, a primatologist at the German Primate Center in Gottingen, and her colleagues previously discovered that female Barbary macaques act a bit like cheerleaders when mating, using their vocalizations to cheer on and stimulate their mates, causing their partners to increase their thrusting rates. The scientists documented two basic types of female mating calls: those linked to partner ejaculation and those linked to no ejaculation. "The peak frequency is higher and the interval between the single units of the call is shorter in ejaculatory compared to non-ejaculatory calls," explained Pfefferle. © 2008 Discovery Communications,

Keyword: Sexual Behavior; Animal Communication
Link ID: 11523 - Posted: 06.24.2010

By Greg Miller SAN FRANCISCO, CALIFORNIA--Imagine not being able to tell your son's voice from that of a complete stranger. Welcome to the life of a 60-year-old British woman known as KH. Although a handful of people have reportedly lost the ability to recognize voices after a stroke or other brain damage, researchers believe KH is the first documented case of someone who never developed this ability in the first place. The case came to light a few years ago when KH read an article in New Scientist magazine about people who can't recognize individuals by face. The article struck a chord, and she contacted the magazine, explaining that she had an analogous voice-recognition problem. For as long as she could remember, the voices of even her closest relatives were indistinguishable. New Scientist contacted Bradley Duchaine, a cognitive neuroscientist featured in the article, and Duchaine invited KH to visit his lab at University College London. A successful management consultant, KH scored average or above on a variety of memory and reasoning tests. Her hearing was normal and a magnetic resonance imaging (MRI) scan of her brain revealed no obvious defects. She told the researchers her problem was limited to recognizing people's voices, explaining that she sometimes introduced herself to business clients by different names so that when they called she could identify them according to who they asked for. © 2008 American Association for the Advancement of Science.

Keyword: Hearing; Language
Link ID: 11522 - Posted: 06.24.2010

Geoff Brumfiel Books and films often dramatize financial-market traders as macho gamblers. Now there may be scientific evidence to back up that pop-culture image: two researchers have linked testosterone levels to the success of traders in one London market. John Coates, a trader-turned-neuroscientist at Cambridge University, UK, started the study after what he saw during his time working the markets: floor traders became frenzied during big winnings, then deeply depressed during downturns. "It was sort of classic manic behaviour," he says. He says that he began to suspect that hormones, specifically testosterone, might be involved because the few female traders appeared to him to be "relatively unaffected". To find out, Coates and his Cambridge colleague Joe Herbert followed 17 male traders for 8 consecutive business days at a firm in London. The researchers took saliva samples from the group before and after the bulk of the day's trading. They analysed the levels of two hormones: testosterone and cortisol, a hormone that is produced in response to uncertainty. © 2008 Nature Publishing Group

Keyword: Hormones & Behavior; Aggression
Link ID: 11521 - Posted: 06.24.2010

There’s no question that the case of 9-year-old Hannah Poling of Athens, Ga., has fueled the controversy about childhood vaccines. But what’s less clear is whether it will help unlock the mysteries of autism. Hannah was 19 months old and developing normally until 2000, when she received five shots against nine infectious diseases. She became sick and later was given a diagnosis of autism. Late last year government lawyers agreed to compensate the Poling family on the theory that vaccines may have aggravated an underlying disorder affecting her mitochondria, the energy centers of cells. (To read more about the decision, click here.) Vaccine critics say the Hannah Poling settlement shows the government has finally conceded that vaccines cause autism. But government officials say Hannah’s case involved a rare medical condition, and there is still no evidence of a link between vaccines and autism. Hannah’s father, Dr. Jon S. Poling, a practicing neurologist in Athens and clinical assistant professor at the Medical College of Georgia, says the case has shifted the autism debate forever and points to a promising new area of research. Writing in The Atlanta Journal-Constitution on Friday, Dr. Poling says there is compelling evidence that mitochondrial disorders, like the one his daughter has, are strongly associated with autism. Copyright 2008 The New York Times Company

Keyword: Autism
Link ID: 11520 - Posted: 06.24.2010

Low doses of a commonly-used anaesthetic could prevent the formation of painful memories, say researchers. The University of California scientists found that sevoflurane gas stopped patients remembering "emotive" images, New Scientist magazine reported. Scans showed it interfered with signals between two key areas of the brain. It is hoped the work could eventually help eradicate rare instances of anaesthetised patients remembering the full horrors of their surgery. While anaesthetic drugs are mainly used to make patients fall unconscious before operations, their effects on the body are frequently far more complex. The Californian researchers, writing in the journal Proceedings of the National Academy of Sciences, were investigating the outcome of much lower doses of the gas than those used prior to surgery. They treated their volunteers either with the anaesthetic, or a placebo gas, and then showed them a series of photographs. Some of these had everyday content, such as a cup of coffee, while others had images designed to provoke a far more powerful emotional response, such as a bloody severed human hand. One week later, the volunteers were asked to recall as many of the images as they could. (C)BBC

Keyword: Learning & Memory
Link ID: 11519 - Posted: 04.14.2008

CHICAGO - U.S. researchers have found a genetic link between autism and a muscle-weakening disorder known as mitochondrial disease, they said on Sunday, in a finding that may open new avenues of research into the causes of autism. “Recent studies have suggested that as many 20 percent of patients with autism have markers for mitochondrial disease,” said Dr. John Shoffner, a neurologist and geneticist at Medical Neurogenetics in Atlanta, who presented his findings at the American Academy of Neurology meeting in Chicago. “There has really not been much work done so far to push that issue,” Shoffner said in a telephone interview. Mitochondrial diseases are a set of genetic disorders in which energy-producing structures in cells are impaired. The disease is often triggered by an illness, such as a high fever, which can result in severe muscle weakening. Shoffner wanted to see if he could identify the underlying genetic mechanisms that might explain this link. He evaluated genetic samples and clinical information gathered on 37 children diagnosed with autism who had been evaluated at his clinic for mitochondrial disease. Copyright 2008 Reuters.

Keyword: Autism; Muscles
Link ID: 11518 - Posted: 06.24.2010

Pascal Belin The use of vocalizations, such as grunts, songs or barks, is extremely common throughout the animal kingdom. Nevertheless, humans are the only species in which these vocalizations have attained the sophistication and communicative effectiveness of speech. How did our ancestors become the only speaking animals, some tens of thousand years ago? Did this change happen abruptly, involving the sudden appearance of a new cerebral region or pattern of cerebral connections? Or did it happen through a more gradual evolutionary process, in which brain structures already present to some extent in other animals were put to a different and more complex use in the human brain? A recent study yields critical new information, uncovering what could constitute the "missing link" between the brain of vocalizing, non-human species and the human brain: evidence that a cerebral region specialized for processing voice, known to exist in the human brain, has a counterpart in the brain of macaques. Neuroscientist Chris Petkov of the Max Planck Institute and his colleagues used functional magnetic resonance imaging (fMRI) to explore the macaque brain. They measured cerebral activity of awake macaque monkeys who were listening to different categories of natural sounds, including macaque vocalizations. They found evidence for a "voice area" in the auditory cortex of these macaques: a discrete region of the anterior temporal lobe in which brain activity was greater for macaque vocalizations than for other sound categories such as natural sounds. This region was observed in several different individuals, even under condition of total anaesthesia. Even more remarkably, the region showed repetition-induced reduction of activity--or neuronal adaptation--in response to different calls coming from a same individual. This finding suggests that this brain region is processing information about the identity of the speaker, a phenomenon that is also observed in the human voice area. © 1995-2007 Scientific American Inc.

Keyword: Language; Evolution
Link ID: 11517 - Posted: 06.24.2010

By GARY MARCUS How much would you pay to have a small memory chip implanted in your brain if that chip would double the capacity of your short-term memory? Or guarantee that you would never again forget a face or a name? There’s good reason to consider such offers. Although our memories are sometimes spectacular — we are very good at recognizing photos, for example — our memory capacities are often disappointing. Faulty memories have been known to lead to erroneous eyewitness testimony (and false imprisonment), to marital friction (in the form of overlooked anniversaries) and even death (sky divers have been known to forget to pull their ripcords — accounting, by one estimate, for approximately 6 percent of sky-diving fatalities). The dubious dynamics of memory leave us vulnerable to the predations of spin doctors (because a phrase like “death tax” automatically brings to mind a different set of associations than “estate tax”), the pitfalls of stereotyping (in which easily accessible memories wash out less common counterexamples) and what the psychologist Timothy Wilson calls “mental contamination.” To the extent that we frequently can’t separate relevant information from irrelevant information, memory is often the culprit. All this becomes even more poignant when you compare our memories to those of the average laptop. Whereas it takes the average human child weeks or even months or years to memorize something as simple as a multiplication table, any modern computer can memorize any table in an instant — and never forget it. Why can’t we do the same? Copyright 2008 The New York Times Company

Keyword: Learning & Memory
Link ID: 11516 - Posted: 06.24.2010

Ewen Callaway Long before you decided to read this story, your brain may have already said "click that link". By scanning the brains of test subjects as they pressed one button or another – though not a computer mouse – researchers pinpointed a signal that divulged the decision about seven seconds before people ever realised their choice. The discovery has implications for mind-reading, and the nature of free will. "Our decisions are predetermined unconsciously a long time before our consciousness kicks in," says John-Dylan Haynes, a neuroscientist at the Bernstein Center for Computational Neuroscience in Berlin, who led the study. It definitely throws our concept of free will into doubt, he adds. This is by no means the first time scientists have cast doubt on conscious free will. In the early 1980s, the late neuroscientist Benjamin Libet uncovered a spark of brain activity three tenths of a second before subjects opted to lift a finger. The activity flickered in a region of the brain involved in planning body movement. But this region might perform only the final mental calculations to move, not the initial decision to lift a finger, Haynes says. © Copyright Reed Business Information Ltd.

Keyword: Attention
Link ID: 11515 - Posted: 06.24.2010

By Brandon Keim You may think you decided to read this story -- but in fact, your brain made the decision long before you knew about it. In a study published Sunday in Nature Neuroscience, researchers using brain scanners could predict people's decisions seven seconds before the test subjects were even aware of making them. The decision studied -- whether to hit a button with one's left or right hand -- may not be representative of complicated choices that are more integrally tied to our sense of self-direction. Regardless, the findings raise profound questions about the nature of self and autonomy: How free is our will? Is conscious choice just an illusion? "Your decisions are strongly prepared by brain activity. By the time consciousness kicks in, most of the work has already been done," said study co-author John-Dylan Haynes, a Max Planck Institute neuroscientist. Haynes updated a classic experiment by the late Benjamin Libet, who showed that a brain region involved in coordinating motor activity fired a fraction of a second before test subjects chose to push a button. Later studies supported Libet's theory that subconscious activity preceded and determined conscious choice -- but none found such a vast gap between a decision and the experience of making it as Haynes' study has. © 2008 CondéNet, Inc.

Keyword: Attention
Link ID: 11514 - Posted: 06.24.2010

Carla K. Johnson A new Harvard study finds that babies and toddlers who sleep fewer than 12 hours daily are at greater risk for being overweight in preschool, startling evidence that the link between sleep and obesity may affect even very young children. TV viewing heightened the effect. The children who slept the least and watched the most television had the greatest chance of becoming obese. "The two (behaviors) are acting independently. In combination, they are particularly risky," said the study's lead author, Dr. Elsie Taveras of Harvard Medical School. The findings, published in April's Archives of Pediatrics & Adolescent Medicine, are based on mothers' reports of their babies' sleep habits and TV viewing, and direct measures of the children's height, weight and skin-fold thickness. Starting when the babies were 6 months old, mothers were asked how long their children napped during the day and how long they slept at night. Moms were asked again when the children were 1 and 2 years old. They were asked about TV time when the children reached age 2. The researchers combined the sleep answers to find an average pattern for each child during the first two years of life. They found 586 of the children slept an average of 12 or more hours a day, and 329 of the children slept less than that. © 2008 Hearst Communications Inc.

Keyword: Sleep; Obesity
Link ID: 11513 - Posted: 06.24.2010

By Alan Mozes -- Construction foreman Jim Mueller was in his early 30s when his memory started to go. He'd forget things: his schedule, his equipment, where he was, and where he was going. Sometimes even the names of his daughters and his wife. But nothing prepared the Mueller family for the doctor's verdict. "When they said Jim had Alzheimer's, I was in shock," Jim's wife, Michelle, quietly recalls. "I mean, I had heard of Alzheimer's because of President Reagan. And I had worked at one time when I was younger to care for someone with Alzheimer's (but) I thought that was for people when they got older. And I really didn't believe it." Jim Mueller, now 39, is, in fact, just one of an estimated 500,000 Americans currently battling the daily ravages of early-onset Alzheimer's (sometimes called young-onset Alzheimer's) -- a form of the incurable and devastating neurodegenerative disease that strikes those in their mid-30s to mid-60s. For the Mueller family, the unexpected havoc wrought by Jim's Alzheimer's diagnosis at the age of 36 has turned every facet of their lives completely upside down. "It was a shock to me, too," Jim confirms. "I thought Alzheimer's, I thought gray hair. And we were just starting to get our feet wet. Just starting our family. Now we've lost everything." © 2008 Scout News LLC.

Keyword: Alzheimers
Link ID: 11512 - Posted: 06.24.2010

By SANDRA BLAKESLEE If Rod Serling were alive and writing episodes for “The Twilight Zone,” odds are he would have leaped on the true story of Anne Adams, a Canadian scientist turned artist who died of a rare brain disease last year. Trained in mathematics, chemistry and biology, Dr. Adams left her career as a teacher and bench scientist in 1986 to take care of a son who had been seriously injured in a car accident and was not expected to live. But the young man made a miraculous recovery. After seven weeks, he threw away his crutches and went back to school. According her husband, Robert, Dr. Adams then decided to abandon science and take up art. She had dabbled with drawing when young, he said in a recent telephone interview, but now she had an intense all-or-nothing drive to paint. “Anne spent every day from 9 to 5 in her art studio,” said Robert Adams, a retired mathematician. Early on, she painted architectural portraits of houses in the West Vancouver, British Columbia, neighborhood where they lived. In 1994, Dr. Adams became fascinated with the music of the composer Maurice Ravel, her husband recalled. At age 53, she painted “Unravelling Bolero” a work that translated the famous musical score into visual form. Copyright 2008 The New York Times Company

Keyword: Alzheimers
Link ID: 11511 - Posted: 06.24.2010

by Molly C. Chalfin, Katrina A. Karkazis, Emily R. Murphy 2008. The American Journal of Bioethics 8(1):1 How and why women and men are different is a topic of enduring scientific and public interest. Over the past decade, the number of neuroscience studies documenting sex differences in brain anatomy, chemistry, and function, and involving cognitive domains such as emotion, memory, and learning, has exploded (Cahill 2006). Although scholars in the field of neuroethics have explored advances in neuroscience from many angles, few, if any, have paid attention to neuroscientific work on sex differences or to gender as a primary category of analysis. Why should we pay special attention to the neuroscience of sex differences? Perhaps the most important reason is that this work will prove important for contested ideas about the so-called nature of human nature. One only need look to the Larry Summers debacle in 2005 to see how contentious the topic is and how far-reaching its effects may be. Although the question of how and why women and men are different is an old one, neuroscience's use of cutting-edge technology - coupled with a growing reliance on science to shed light on complex human behavior - increases the likelihood that this work will leap to the forefront of public discussion and debate about social equality. While neuroscience is concerned with elucidating the origin and extent of behavioral and cognitive differences between women and men, the questions that predominate for us are of a different nature: How ought we disseminate this information into a sensitive social environment that has a history of bias and discrimination against women? What are the implications of this work for our understandings of what makes us women and men? How should this research be applied in educational, medical, and legal contexts, if at all? ©2000-5 Taylor & Francis Group & bioethics education network

Keyword: Sexual Behavior
Link ID: 11510 - Posted: 06.24.2010

From The Economist print edition FASHION is a strange thing, and many fields are susceptible to it—not least, medicine. There has, for example, been a vogue (among commentators, if not among doctors) to ascribe the rising number of cases of autism diagnosed over the past couple of decades to childhood vaccinations against measles, mumps and rubella. That this is fashion rather than reality is suggested by the fact that the explanation proffered in Britain has been that such vaccines provoke an immune response that damages the nervous system, whereas Americans have blamed residual mercury in the same vaccines. It is now pretty well established that vaccination does not create autism. But the rise in the number of recorded cases is real enough. In Britain, for example, the rate of diagnosis has risen from 50 per 100,000 in 1990 to 400 per 100,000 today. That must have a cause. And one popular hypothesis is that this cause, too, is fashion—but among doctors rather than columnists. Demonstrating that has been difficult. But a paper in this month's Developmental Medicine & Child Neurology, by Dorothy Bishop and her colleagues at Oxford University, goes a long way towards doing so. Dr Bishop reasoned it was unlikely that people now labelled autistic would, in the past, have been thought healthy, but that it was quite plausible they might have been given some other diagnosis. With this in mind, she looked at a group who had been diagnosed as children with a particular condition that was not autism, and rediagnosed them using present-day criteria. © The Economist Newspaper Limited 2008

Keyword: Autism
Link ID: 11509 - Posted: 06.24.2010

By Nikhil Swaminathan Scientists for the first time have identified long-term changes in mice brains that may shed light on why addicts get hooked on drugs—in this case methamphetamines—and have such a tough time kicking the habit. The findings, reported in the journal Neuron, could set the stage for new ways to block cravings—and help addicts dry out. Researchers, using fluorescent tracer dye, discovered that mice given methamphetamines for 10 days (roughly equivalent to a human using it for two years) had suppressed activity in a certain area of their brains. Much to their surprise, normal function did not return even when the drug was stopped, but did when they administered a single dose of it again after the mice had been in withdrawal. Study co-author Nigel Bamford, a pediatric neurologist at the University of Washington School of Medicine, says that if similar changes occur in humans, it will indicate that an effective way to fight addiction may be to design therapies that target the affected area—the striatum, a forebrain region that controls movement but also has been linked to habit-forming behavior. Previous research has shown that the drug stimulates nerve cells in the midbrain to release dopamine into the synapses (connections between neurons) in the striatum. Dopamine (which is connected to reward processing, motivation and attention) is one of the brain's primary neurotransmitters, the chemical messengers by which one neuron triggers its neighbor to fire a nerve impulse. © 1996-2008 Scientific American Inc.

Keyword: Drug Abuse
Link ID: 11508 - Posted: 06.24.2010

By Constance Holden Reprogrammed body cells continue to show promise as a treatment for disease. Last year, scientists used the cells, called induced pluripotent stem (iPS) cells, to successfully treat sickle cell disease in mice (ScienceNOW, 6 December 2007). Now, investigators have shown that neurons derived from iPS cells alleviate a Parkinson's-like movement disorder in rats. A team led by Marius Wernig, a postdoc in the lab of stem cell researcher Rudolf Jaenisch at the Massachusetts Institute of Technology in Cambridge generated iPS cells from mouse tail cells by adding four genes. The researchers then differentiated the cells into neural progenitor cells using the same techniques that guide the differentiation of embryonic stem cells. When the cells were injected into the brains of fetal mice, they developed into several types of brain cells and formed connections in a half-dozen brain regions. To see whether the iPS cells could be grown into dopamine-producing neurons that could be used to treat disease, the researchers gave adult rats a Parkinson's-like movement disorder. They did this by injecting a substance that killed dopamine neurons on one side of the brain, causing the rats to move in circles. Batches of dopamine neurons grown from the mouse iPS cells were then injected into the brain area--the striatum--most stricken by Parkinson's in five rats. Within 8 weeks, four of the five treated rats showed significant recovery of function and stopped going in circles, the researchers report online today in Proceedings of the National Academy of Sciences. © 2008 American Association for the Advancement of Science.

Keyword: Parkinsons; Stem Cells
Link ID: 11506 - Posted: 06.24.2010

Randolph E. Schmid -- Dyslexia affects different parts of children's brains depending on whether they are raised reading English or Chinese. That finding, reported in Monday's online edition of Proceedings of the National Academy of Sciences, means that therapists may need to seek different methods of assisting dyslexic children from different cultures. "This finding was very surprising to us. We had not ever thought that dyslexics' brains are different for children who read in English and Chinese," said lead author Li-Hai Tan, a professor of linguistics and brain and cognitive sciences at the University of Hong Kong. "Our finding yields neurobiological clues to the cause of dyslexia." Millions of children worldwide are affected by dyslexia, a language-based learning disability that can include problems in reading, spelling, writing and pronouncing words. The International Dyslexia Association says there is no consensus on the exact number because not all children are screened, but estimates range from 8 percent to 15 percent of students. Reading an alphabetic language like English requires different skills than reading Chinese, which relies less on sound representation, instead using symbols to represent words. Past studies have suggested that the brain may use different networks of neurons in different languages, but none has suggested a difference in the structural parts of the brain involved, Tan explained. © 2008 Discovery Communications

Keyword: Dyslexia; Language
Link ID: 11505 - Posted: 06.24.2010