Biological Psychology Links

By TARA PARKER-POPE For kids around the country it’s back-to-school time. But for many of them, it’s also the return of headache season. Doctors say frequent headaches and migraines are among the most common childhood health complaints, yet the problem gets surprisingly little attention from the medical community. Many pediatricians and parents view migraines as an adult condition. And because many children complain of headaches more often during the school year than the summer, parents often think a child is exaggerating symptoms to get out of schoolwork. Often the real issue, say doctors, is that changes in a child’s sleep schedule, including getting up early for school and staying up late to study, as well as skipping breakfast, not drinking enough water and weather changes can all trigger migraines when the school year starts. “In many areas people just don’t think kids can get migraines,” says Dr. Andrew Hershey, professor of pediatrics and neurology and director of the headache center at Cincinnati Children’s Hospital Medical Center. “But kids shouldn’t be missing activities and having trouble at school because they’re having headaches. If it happens, it shouldn’t be ignored.” Migraine is an inherited neurological condition characterized by severe, often disabling headache pain. During a migraine attack, a number of changes occur throughout the brain causing dilation of blood vessels; severe pain; increased sensitivity to lights, sounds and smells; nausea and vomiting; and other symptoms. It’s estimated that about 10 percent of young children and up to 28 percent of older teenagers suffer from migraines. (Hormonal changes during puberty can also be a trigger.) Copyright 2010 The New York Times Company

By GINA KOLATA BETHESDA, Md. — The scene was a kind of science court. On trial was the question “Can anything — running on a treadmill, eating more spinach, learning Arabic — prevent Alzheimer’s disease or delay its progression?” To try to answer that question, the National Institutes of Health sponsored the court, appointing a jury of 15 medical scientists with no vested interests in Alzheimer’s research. They would hear the evidence and reach a judgment on what the data showed. For a day and a half last spring, researchers presented their cases, describing studies and explaining what they had hoped to show. The jury also heard from scientists from Duke University who had been commissioned to look at the body of evidence — hundreds of research papers — and weigh it. And the jury members had read the papers themselves, preparing for this day. The studies included research on nearly everything proposed to prevent the disease: exercise, mental stimulation, healthy diet, social engagement, nutritional supplements, anti-inflammatory drugs or those that lower cholesterol or blood pressure, even the idea that people who marry or stay trim might be saved from dementia. And they included research on traits that might hasten Alzheimer’s onset, like not having much of an education or being a loner. It is an issue that has taken on intense importance because scientists recently reported compelling evidence that two types of tests, PET scans of Alzheimer’s plaque in the brain and tests of spinal fluid, can find signs of the disease years before people have symptoms. That gives rise to the question: What, if anything, can people do to prevent it? Copyright 2010 The New York Times Company

By John Biemer, Special to the Chicago Tribune Catholic nuns are known for their acts of charity, but Sister Adrienne Schmidt has found a way to give beyond the grave: She will donate her brain to science. First, though, she is exercising it in an annual battery of memory tests administered by researchers at Chicago's Rush University. Schmidt, 82, repeats two-digit numbers, then three, four, five, six and seven digits. She names as many animals as she can in a minute. She listens to a 30-second story about a school cafeteria cook who is robbed of $56. Half an hour later, she must repeat as many details as she can. The yearly tests are designed to provide a history of how her brain is aging. When the time comes, Schmidt's brain will join hundreds of others in 38 cooling units in a laboratory at the school's medical center. Schmidt is one of the original participants in Rush University's Religious Orders Study, which began in 1993. It is one of a handful of studies nationwide that uses donated brains with a rich and detailed clinical history gleaned from years of memory tests and physical exams. Funding for the study is slated to run out next year, but researchers are preparing a federal grant proposal in hopes of extending the study five years, because it continues to yield a bounty of results. Copyright © 2010, Los Angeles Times

By Emily Sohn Chemicals on our produce may contribute to behavior problems in our kids, suggest three new studies. The studies, which looked at a class of pesticides called organophosphates (OP), linked exposure to the chemicals with attention disorders in children, with perhaps the most dramatic impacts to kids who are exposed in the womb and those who are genetically most susceptible. Because pesticide residues linger on fruits and vegetables, the findings suggest that people either buy organic or take the time to wash their produce well. "We don't want women to not eat fruits and vegetables because it's very important to eat them during pregnancy," said Brenda Eskenazi, an epidemiologist and neuropsychologist at the University of California, Berkeley. "I just let water run really thoroughly over fruits, and I rub them so they're clean." Organophosphates are a set of common pesticides that work by attacking the nervous systems of insects. When people are exposed to high levels of the chemicals, they can develop anxiety, confusion impaired concentration, and other serious symptoms. More recently, scientists have started to wonder how chronic exposure at low levels might be affecting people, especially kids, whose nervous systems are still developing. To find out, Eskenazi and colleagues followed up on a long-term study that has tracked more than 300 Mexican-American women in an agriculturally intensive region of California since they first became pregnant in 1999 or 2000. When the women were pregnant, the researchers measured levels of pesticide breakdown products in their urine. More recently, they collected urine samples from the kids and evaluated measures of attention. © 2010 Discovery Communications, LLC.

By Katherine Harmon Children with autism often focus intently on a single activity or feature of their environment. New research might help to explain this behavioral trend, providing evidence that the brains of young people with autism are slower to integrate input coming from more than one sense at the same time. During study of the disorder decades ago, research into these basic tendencies was common. But in subsequent years, scientists have tended to focus more on complex issues, ranging from communication troubles to underlying genetic patterns. Recently, however, more studies have set their sights back on some of the simple processes that most people take for granted, such as sensory intake, as a way to better understand more high-level manifestations, such as social interaction issues. "We believe that these things interact in very significant ways," says Sophie Molholm, an associate professor of neuroscience at Albert Einstein College of Medicine and co-author of a new study about multi-sensory processing. The research, published online August 19 in Autism Research, used electroencephalograms (EEGs) to measure electrical activity in the brain through the scalp of subjects as they encountered various stimuli. Seventeen children (ages six to 16 years) with autism—and 17 age- and IQ-matched normally developing kids—watched a silent video of their choice throughout the testing. Meanwhile, tones and vibrations were administered in random order, sometimes separately, sometimes at the same time. The EEG readings were time-stamped to the stimuli and compared across all of the children to assess brain activity trends during single- and multi-sensory stimulation. Although the video presented visual stimuli, Molholm points out that because it was a consistent exposure throughout the experiments and the EEG readings were set to pick up on the sound and somatosensory stimuli and averaged out over so many tests, it becomes akin to "background brain activity that will sum to zero," she notes. "It's really just something to keep them busy." © 2010 Scientific American,

By Karen Weintraub It was the week the medication didn’t work that convinced Melissa Zolecki. She thinks her son Matthew got a bottle of inactive dummy pills that week by accident. And the change in his behavior was striking. The MIND Institute at the University of California Davis is testing an antibiotic called minocycline against a placebo in 60 children with Fragile X. The Fragile X Research Foundation of Canada is studying the benefits of the same drug in 20 teenagers and young adults. Seaside Therapeutics is testing the drug arbaclofen , which it is calling STX209, against a placebo in 60 children and adults, to determine its safety and an appropriate dose. Some of those study participants will continue on the drug past the initial four-week trial. Roche is testing a similar drug it is calling RO4917523 against a placebo in 60 adults with Fragile X. Novartis recently completed testing the safety and dosing of a drug called AFQ056 against a placebo in 30 adults with Fragile X. Stanford University researchers are testing the drug donepezil, a medication that enhances the function of the brain chemical acetylcholine. This trial includes 50 patients ages 12 to 21. © 2010 NY Times Co.

by Jon Cohen Thirty-five years ago, researchers studying chimpanzees in the wild noticed that neighboring communities had distinct grooming behaviors that could not be explained by differences in their environments. They contended that these behavioral idiosyncrasies were learned, or "cultural," and other scientists soon began noting group-specific tool uses and courting behaviors that also didn't appear to be environmental. But in a new study, researchers say some of these behaviors may be genetic after all. Before that 1975 revelation, few researchers had observed different communities of wild chimpanzees, and no one had even recognized that these behavioral differences existed. Investigators have been arguing about whether chimps truly have culture ever since. Proponents of culture published a landmark Nature paper in 1999 documenting 39 behaviors that were frequently observed in some communities and never seen in others. In the article's wake, a flood of reports began to appear about culture in other species, and the debates roiled on, with endless discussions about the meaning of the word itself. The new study, published online tomorrow in the Proceedings of the Royal Society B, examines partial sequences of the mitochondrial DNA (mtDNA) from wild chimpanzees in nine different groups. This DNA is handy because it's inherited only from mothers, and only chimp females typically move to new communities. Team members examined the links between the groups and 38 of the 39 supposed cultural variants documented in the earlier report. The study does not link behaviors to specific genes or even conclude that there is a genetic explanation. Rather, it assesses whether genetic differences can be excluded as an explanation for each behavior; it finds that they cannot more than half the time. © 2010 American Association for the Advancement of Science.

By GINA KOLATA The failure of a promising Alzheimer’s drug in clinical trials highlights the gap between diagnosis — where real progress has recently been made — and treatment of the disease. It was not just that the drug, made by Eli Lilly, did not work — maybe that could be explained by saying the patients’ illness was too far advanced when they received it. It was that the drug actually made them worse, the company said. And the larger the dose they took, the worse were patients’ symptoms of memory loss and inability to care for themselves. Not only that, the drug also increased the risk of skin cancer. So when Lilly announced on Tuesday that it was ending its large clinical trials of that drug, semagacestat, researchers were dismayed. “Obviously, this is disappointing news, to say the least,” said Dr. Steven Paul, an Alzheimer’s researcher and a recently retired executive vice president at Lilly. Beyond the setback for Lilly, the study raises questions about a leading hypothesis of the cause of Alzheimer’s and how to treat it. The idea, known as the amyloid hypothesis, says the disease occurs when a toxic protein, beta amyloid, accumulates in the brain. The idea is that if beta amyloid levels are reduced, the disease might be slowed, halted or even prevented if treatment starts early enough. The Lilly drug, like most of the more than 100 Alzheimer’s drugs under development, blocks an enzyme, gamma secretase, needed to make beta amyloid. It was among the first shown to breach the blood-brain barrier and reduce levels of beta amyloid in the brain. And, company studies showed, it did reduce amyloid production. Copyright 2010 The New York Times Company

By CHARLES Q. CHOI The infants and toddlers resemble cyborgs as they waddle and crawl around the playroom with backpacks carrying wireless transmitters and cameras strapped to their heads. Each has one camera aimed at the right eye and another at the field of view, and both send video to monitors nearby. When the video feeds are combined, the result is a recording in which red cross hairs mark the target of a child’s gaze. Scientists are using the eye-tracking setup to learn how children look at the world as they figure out how to interact with it. In the lab, children 5 months and older crawl and walk up, down and over an obstacle course of adjustable wooden slopes, cliffs, gaps and steps. And to add to the challenge, the subjects are sometimes outfitted with Teflon-coated shoes or lead-weighted vests. It may seem like the set for a new reality television show, but there are no prizes, except perhaps for the researchers. They hope to understand what prompts one child to respond to another, how infants coordinate their gaze with their hands and feet to navigate around obstructions or handle objects, and how these very young children adapt to changes, like those brought on by slippery footwear. The findings provided by these eye-trackers so far (the first light enough for children to wear) suggest that infants may be more capable of understanding and acting on what they see than had been thought. “Quick gazes at obstacles in front of them or at their mothers’ faces may be all they need to get the information they want. They seem to be surprisingly efficient,” said John Franchak, a doctoral candidate in developmental psychology at New York University. Copyright 2010 The New York Times Company

By John von Radowitz, Mid-life stress can increase the risk of women developing Alzheimer's disease, a study has shown. Women who reported repeated episodes of stress and anxiety in middle age were up to twice as likely to develop dementia than those who did not, a team of Swedish scientists found. The majority of those affected were diagnosed with Alzheimer's, the most common form of dementia. Researchers followed the progress of 1,415 women between 1968 and 2000. Three surveys in 1968, 1974 and 1980 were carried out to assess levels of psychological stress experienced by the women, who were aged between 38 and 60 at the start of the study. Stress was defined as a "sense of irritation, tension, nervousness, anxiety, fear or sleeping problems" lasting a month or more. During the course of the study, 161 of the women taking part developed dementia, mainly in the form of Alzheimer's disease. Dementia risk was 65% higher in women who suffered frequent stress in middle age. ©independent.co.uk

By GINA KOLATA In 2003, a group of scientists and executives from the National Institutes of Health, the Food and Drug Administration, the drug and medical-imaging industries, universities and nonprofit groups joined in a project that experts say had no precedent: a collaborative effort to find the biological markers that show the progression of Alzheimer’s disease in the human brain. Now, the effort is bearing fruit with a wealth of recent scientific papers on the early diagnosis of Alzheimer’s using methods like PET scans and tests of spinal fluid. More than 100 studies are under way to test drugs that might slow or stop the disease. And the collaboration is already serving as a model for similar efforts against Parkinson’s disease. A $40 million project to look for biomarkers for Parkinson’s, sponsored by the Michael J. Fox Foundation, plans to enroll 600 study subjects in the United States and Europe. The work on Alzheimer’s “is the precedent,” said Holly Barkhymer, a spokeswoman for the foundation. “We’re really excited.” The key to the Alzheimer’s project was an agreement as ambitious as its goal: not just to raise money, not just to do research on a vast scale, but also to share all the data, making every single finding public immediately, available to anyone with a computer anywhere in the world. Copyright 2010 The New York Times Company

By LARA SALAHI Researchers claimed to have identified markers for early Alzheimer's disease in some patients by analyzing results of a spinal tap, according to an article published Monday in the Archives of Neurology. Their results, they claim, are nearly 100 percent accurate in predicting Alzheimer's in some patients. But many experts are quick to question how reliable these results may be. "The test is an advance and has tremendous research potential. This is sure," said Karl Herrup, chair of Cell Biology and Neuroscience at Rutgers University in Piscataway, N.J. But, he added, "a dangerous, though unintended, consequence of the '100 percent accuracy' descriptor is that people who may not be on the fast track to Alzheimer's will end up frightened unnecessarily from a positive test result." "[T]he fear of [Alzheimer's disease] is so strong in our population that feeding it any way seems not in our best overall interest." And ABC News Senior Health and Medical Editor Dr. Richard Besser said the test is not yet ready for prime time. "This test isn't ready to be used on healthy, normal people," Besser said on "Good Morning America. It will be useful for research, doing drug trials in a group of people who may be at high likelihood to go on for Alzheimer's disease." © 2010 ABC News

By Jason Palmer The brain appears to be a vastly interconnected network much like the Internet, according to new research. That runs counter to the 19th-Century "top-down" view of brain structure. A novel technique to track signals across tiny brain regions has revealed connections between regions associated with stress, depression and appetite. The research, which has been published in Proceedings of the National Academy of Sciences journal, may lead to a full map of the nervous system. Larry Swanson and Richard Thompson from the University of Southern California in Los Angeles, US, isolated a small section of a rat's brain in the nucleus accumbens - a brain region long associated with pleasure and reward. Their technique hinges on the injection of "tracers" at precise points in the brain tissue. These are molecules that do not interfere with the movement of signals across the tissue, but can be illuminated and identified using a microscope. What is new is that the researchers injected two tracers at the same point at the same time: one that showed where signals were going, and one that showed where they were coming from. The approach can show up to four levels of connection. If the brain has a hierarchichal structure like a large company, as neurology has long held, the "to" and "from" diagram would show straight lines from independent regions up towards a central processing unit: the company's boss. (C)BBC

by Greg Miller In children, an anxious temperament can be a warning sign. Kids who are painfully shy and nervous are more prone to anxiety disorders and depression later in life, and they're more likely to self-medicate with alcohol and other drugs. But what causes a child to have an anxious temperament in the first place? A new study with monkeys finds that an anxious temperament is partly heritable and that it's tied to a particular brain region involved in emotion. Children with an anxious temperament often freeze up when they meet a stranger or encounter a social situation they perceive as threatening, says Ned Kalin, a psychiatrist and neuroscientist at the University of Wisconsin, Madison. Kalin and his colleagues have found that some young monkeys do much the same thing. When a human "intruder" enters the room and approaches their cage without making eye contact, these anxious youngsters freeze in place and grow quiet. Their stress hormone levels spike, too. In the new study, published in the 12 August issue of Nature, Kalin and colleagues studied 238 young rhesus monkeys from a family of more than 1500 lab-raised monkeys with well-documented pedigrees. By analyzing the family connections among the young monkeys, which ranged from siblings to distant cousins, the researchers found that an anxious temperament was partly heritable, accounting for about 36% of the variability in individual monkeys' responses on the human intruder test (as measured by the reduction in movement and vocalization and increase in stress hormone levels). © 2010 American Association for the Advancement of Science.

Regions of the brain are known to differ in people with autism. Red and orange show areas that are thicker or larger, while the blue shows a reduction in size compared with a non-autistic brain. Regions of the brain are known to differ in people with autism. Red and orange show areas that are thicker or larger, while the blue shows a reduction in size compared with a non-autistic brain. (MRC) Autism in adults can be diagnosed using MRI brain scans, British scientists have found. The 15-minute scans were used to identify autism spectrum disorder (ASD) with an accuracy of 90 per cent in 20 people who were previously diagnosed. "Our study offers a 'proof of concept' for describing the complex multidimensional grey matter differences in ASD," Dr. Christine Ecker, a lecturer in forensic and neurodevelopmental sciences at London's Institute of Psychiatry and her co-authors concluded in Wednesday's issue of the Journal of Neuroscience. In the experiment, magnetic resonance imaging scans were reconstructed into 3-D images and analyzed using computer software programmed to spot structural changes in the brain's grey matter by measuring areas that relate to behaviour, language and vision. Changes in shape and thickness point to the disorder. A capability to diagnose ASD based on objective biological tests rather than the current method of relying on personality traits could help identify patients more quickly who need treatment, Ecker said. © CBC 2010

By GINA KOLATA Researchers report that a spinal fluid test can be 100 percent accurate in identifying patients with significant memory loss who are on their way to developing Alzheimer’s disease. Although there has been increasing evidence of the value of this and other tests in finding signs of Alzheimer’s, the study, which will appear Tuesday in the Archives of Neurology, shows how accurate they can be. The new result is one of a number of remarkable recent findings about Alzheimer’s. After decades when nothing much seemed to be happening, when this progressive brain disease seemed untreatable and when its diagnosis could be confirmed only at autopsy, the field has suddenly woken up. Alzheimer’s, medical experts now agree, starts a decade or more before people have symptoms. And by the time there are symptoms, it may be too late to save the brain. So the hope is to find good ways to identify people who are getting the disease, and use those people as subjects in studies to see how long it takes for symptoms to occur and in studies of drugs that may slow or stop the disease. Researchers are finding simple and accurate ways to detect Alzheimer’s long before there are definite symptoms. In addition to spinal fluid tests they also have new PET scans of the brain that show the telltale amyloid plaques that are a unique feature of the disease. And they are testing hundreds of new drugs that, they hope, might change the course of the relentless brain cell death that robs people of their memories and abilities to think and reason. Copyright 2010 The New York Times Company

By NICHOLAS WADE Two research reports published Friday offer novel approaches to the age-old dream of regenerating the body from its own cells. Animals like newts and zebra fish can regenerate limbs, fins, even part of the heart. If only people could do the same, amputees might grow new limbs and stricken hearts be coaxed to repair themselves. But humans have very little regenerative capacity, probably because of an evolutionary trade-off: suppressing cell growth reduced the risk of cancer, enabling humans to live longer. A person can renew his liver to some extent, and regrow a fingertip while very young, but not much more. In the first of the two new approaches, a research group at Stanford University led by Helen M. Blau, Jason H. Pomerantz and Kostandin V. Pajcini has taken a possible first step toward unlocking the human ability to regenerate. By inactivating two genes that work to suppress tumors, they got mouse muscle cells to revert to a younger state, start dividing and help repair tissue. What is true of mice is often true of humans, and although scientists are a long way from being able to cause limbs to regenerate, the research is attracting attention. Jeremy Brockes, a leading expert on regeneration at University College London, said the report was “an excellent paper.” Though there is a lot still to learn about the process, “it is hard to imagine that it will not be informative for regenerative medicine in the future,” he said. Copyright 2010 The New York Times Company

By Katherine Harmon More than 26 percent of American adults were obese as of 2009—compared with less than 20 percent in 2000, according to a new report from the U.S. Centers for Disease Control and Prevention. And the number of U.S. states with more than 30 percent of their population topping a body mass index (BMI) of 30 tripled between 2007 and 2009. With this accelerating epidemic, researchers are looking for clues beyond daily diet and exercise to explain our propensity for extra poundage—and many are finding evidence in the very first stages of life. A growing number of analyses have found a convincing link among a heavier mother-to-be, increases in her baby's birth weight, and the child's later risk of obesity. In many past observational studies, however, basic genetics or environmental factors could be blamed for this association. A new study of 513,501 mothers and 1,164,750 of their children born across 15 years aimed to take genetics out of the equation by assessing maternal and infant weight only for those women who had more than one child. "By making comparisons of two or more infants born to the same mother, we were able to factor out the role of genetics," says David Ludwig, an associate professor of pediatrics, director of the Obesity Program at Children's Hospital Boston and co-author of the new study. Women who gained more than 24 kilograms during a pregnancy (which occurred in about 12 percent of pregnancies) added an average of 147.4 additional grams to their baby's birth weight than those who gained about 7.5 to 10 kilograms. © 2010 Scientific American,

By Emily Anthes One of the first things that anatomy students learn is that the brain is divided down the center. In most people, one half, or hemisphere, plays a dominant role. Handedness has long been a crude measure of hemispheric dominance, because each side of the brain controls the opposite side of the body. Right-handers, for instance, are likely to have dominant left hemispheres. Today researchers are realizing that studying ambidextrous children (who have no dominant hand) could yield insights into the consequences of an unusually symmetrical brain. A team of European researchers recently assessed nearly 8,000 Finnish children and showed that mixed-handed children are at increased risk for linguistic, scholastic and attention-related difficulties. At age eight, mixed-handed kids were about twice as likely to have language and academic difficulties as their peers. By the time the children were 16, they also were twice as likely to have symptoms of ADHD—and their symptoms were more severe than those of right- or left-handed students. Ambidexterity is not causing these problems. Rather “handedness is really a very crude measure of how the brain is working,” says Alina Rodriguez, a clinical psychologist at King’s College London and the study’s lead author. In typical brains, language is rooted in the left hemisphere, and networks that control attention are anchored in the right—but brains without a dominant hemisphere may be working and communicating differently. © 2010 Scientific American,

By GINA KOLATA Will Alzheimer’s disease, a terrible degenerative brain disease with no treatments and no clear guidelines for diagnosis before its end stages, become like heart disease? That might mean early markers of risk, analogous to high cholesterol levels, that predict who is likely to get it. And it might mean drugs that actually prevent it. That is the hope behind new diagnostic guidelines being proposed by the National Institute on Aging and the Alzheimer’s Association. In July, when the groups first announced their proposed guidelines, they were met with some skepticism and anger. Why suggest ways of diagnosing the disease before a person even has symptoms? Why tell people they are doomed? And are those early diagnosis guidelines just a sop to pharmaceutical companies so they can start marketing expensive, and perhaps not very effective, new drugs? So the Alzheimer’s Association, with participation from the National Institute on Aging, held a conference call on Wednesday to clarify their position. They wanted, in particular, to explain why they advocated using so-called biomarkers, like scans for amyloid plaque in the brain, a unique feature of Alzheimer’s, and tests of cerebrospinal fluid. Such brain scans are still experimental. Copyright 2010 The New York Times Company

Chapter 7. Life-Span Development of the Brain and Behavior