Jon Hamilton A brain system involved in everything from addiction to autism appears to have evolved differently in people than in great apes, a team reports Thursday in the journal Science. The system controls the production of dopamine, a chemical messenger that plays a major role in pleasure and rewards. "Humans have evolved a dopamine system that is different than the one in chimpanzees," says Nenad Sestan, an author of the study and a professor of neuroscience at Yale. That could help explain why human behavior is so different from our nearest relatives even though our brains are remarkably similar, he says. It might also shed light on why people are vulnerable to mental disorders such as autism. The finding came from a massive, multicenter effort to compare the brains of several species. Researchers looked at 247 samples of brain tissue from five macaque monkeys, five chimpanzees and six people. They looked at which genes were turned on or off in 16 regions of the brain. And in most places, the differences among species were subtle. But there was a striking difference in the neocortex, an area of the brain that is much more developed in people than in chimpanzees. The team found that a gene called TH, which is involved in the production of dopamine, was expressed in the neocortex of people, but not chimpanzees. "That caught our attention," says Andre Miguel Sousa, another author of the study who works in Sestan's lab at Yale. Dopamine is best known for its role in the brain's reward system, which responds to everything from sex and food to addictive drugs. But dopamine also helps regulate emotional responses, memory and movement. And abnormal dopamine levels have been linked to disorders including Parkinson's, schizophrenia and autism. © 2017 npr

Keyword: Drug Abuse; Evolution
Link ID: 24353 - Posted: 11.24.2017

By Diana Kwon | Most of us are familiar with the role of smell in our dining habits—that basket of freshly baked cookies is usually much harder to resist than a plate of odorless carrot sticks, and the taste of food is strongly tied to its aroma. But animals’ sense of smell is even more intricately linked with eating and metabolism. Prior studies have shown that, in humans, fasting enhances olfactory sensitivity, while satiety reduces it. And a new study, published today (July 5) in Cell Metabolism, suggests that, at least in mice, this link may go even further—animals engineered to lack a sense of smell gained less weight and burned more fat than their unaltered counterparts. This difference in weight gain was almost entirely due to alterations in body fat composition. “The major thing was that [the mice lacking smell] weren’t gaining fat,” coauthor Andrew Dillin, a biology professor at the University of California, Berkeley, tells The Scientist. “Somehow, the olfactory system is engaging the major control circuit in the brain that controls peripheral metabolism . . . and that is turning on a program to burn fat.” Dillin says his team was interested in knowing whether simply eating fattening food led to weight gain, or if it was how the olfactory system “perceived” those calories that matters. To assess this link between olfaction and metabolism, scientists genetically engineered mice that expressed a gene for a diphtheria toxin receptor on olfactory sensory neurons. Once the animals were around seven weeks old, the researchers injected the toxin to kill off these nerve cells and found that these animals had lost their sense of smell. Control animals generated without this receptor retained all their smell neurons after receiving the toxin. © 1986-2017 The Scientist

Keyword: Obesity; Chemical Senses (Smell & Taste)
Link ID: 24352 - Posted: 11.24.2017

By Abby Olena Two people with a rare genetic disorder have helped shed light on the fundamental neuroscience of appetite and, scientists say, opened up a new target for potential obesity treatments. Neonatal progeroid syndrome (NPS) affects only a handful of people worldwide. The most telling features of the condition are an aged appearance due to an absence of the fat layer under the skin and extreme thinness. Researchers report in in Nature Medicine today (November 6) that a glucose-releasing hormone involved in the disease crosses the blood-brain barrier and homes in on neurons that regulate appetite in mice. The study suggests it might be possible to target the hormone, asprosin, in the treatment of diabetes and obesity. “Rare diseases with extreme phenotypes like this are very valuable to learn important things that then apply to more common diseases,” says coauthor and medical geneticist Atul Chopra of Baylor College of Medicine in Houston, Texas. Chopra and colleagues showed in a previous study that patients with NPS have mutations near the end of a gene called FBN1, which encodes profibrillin. It was already known that profibrillin is processed to form fibrillin 1, an extracellular matrix protein. The 140-amino-acid chunk cleaved from the end of profibrillin, which Chopra’s group named asprosin, is secreted by adipose tissue and functions as a hormone that causes the liver to make glucose. They determined that two individuals with NPS are heterozygous for FBN1 mutations and have greatly reduced levels of circulating asprosin. © 1986-2017 The Scientist

Keyword: Obesity
Link ID: 24351 - Posted: 11.24.2017

By Bob Grant In 1971, a 27-year-old, 456-pound man went to the University of Dundee’s department of medicine in Scotland looking for help. Patient A.B., as doctors referred to him, needed to lose weight. His physicians recommended a short but drastic course of action: stop eating altogether. The patient responded so well to a brief stint without food that he decided to prolong the deprivation—for more than a year. “[H]is fast was continued into what is presently the longest recorded fast (Guinness Book of Records, 1971),” the clinicians wrote in a 1973 case report, claiming A.B. suffered little or no untoward effects on his health.1 And at the end of his 382-day dietary abstinence, during which he had ingested only vitamin supplements, yeast, and noncaloric fluids, A.B. had lost a remarkable 276 pounds. When doctors checked back in on A.B. five years later, their patient reported gaining back only about 15 pounds. Although aspects of this published report seem almost unbelievable, and the period of fasting is obviously extreme, the case highlights some of the metabolic dynamics that result when bodies are deprived of food. For example, when external calories stop fueling an animal’s metabolism, stores of triglycerides in fat cells are mobilized, and levels of ketones—chemicals that result from the burning of fat for fuel—rise. Decreases in body weight follow. © 1986-2017 The Scientist

Keyword: Obesity
Link ID: 24350 - Posted: 11.24.2017

By Philippa Roxby Confronting an avatar on a computer screen helped patients hearing voices to cope better with hallucinations, a UK trial has found. Patients who received this therapy became less distressed and heard voices less often compared with those who had counselling instead. Experts said the therapy could add an important new approach to treating schizophrenia hallucinations. The trial, on 150 people, is published in The Lancet Psychiatry journal. It follows a much smaller pilot study in 2013. Hallucinations are common in people with schizophrenia and can be threatening and insulting. One in four patients continues to experience voices despite being treated with drugs and cognitive behavioural therapy. In this study, run by King's College London and University College London, 75 patients who had continued to hear voices for more than a year, were given six sessions of avatar therapy while another 75 received the same amount of counselling. In the avatar sessions, patients created a computer simulation to represent the voice they heard and wanted to control, including how it sounded and how it might look. Image copyright King's College London Image caption Three avatars created by people taking part in the therapy The therapist then voiced the avatar while also speaking as themselves in a three-way conversation to help the patient gain the upper hand. Prof Tom Craig, study author from King's College London, said getting patients to learn to stand up to the avatar was found to be safe, easy to deliver and twice as effective as counselling at reducing how often voices were heard. "After 12 weeks there was dramatic improvement compared to the other therapy," he said. "With a talking head, patients are learning to confront and get replies from it. "This shifts the idea that the voice is all-controlling," he said. © 2017 BBC.

Keyword: Schizophrenia
Link ID: 24349 - Posted: 11.24.2017

By Mary Beth Aberlin Like the entomologist in search of colorful butterflies, my attention has chased in the gardens of the grey matter cells with delicate and elegant shapes, the mysterious butterflies of the soul, whose beating of wings may one day reveal to us the secrets of the mind. —Santiago Ramón y Cajal, Recollections of My Life Based on this quote, I am pretty certain that Santiago Ramón y Cajal, a founding father of modern neuroscience, would approve of this month’s cover. The Spaniard had wanted to become an artist, but, goaded by his domineering father into the study of medicine, Ramón y Cajal concentrated on brain anatomy, using his artistic talent to render stunningly beautiful and detailed maps of neuron placement throughout the brain. Based on his meticulous anatomical studies of individual neurons, he proposed that nerve cells did not form a mesh—the going theory at the time—but were separated from each other by microscopic gaps now called synapses. Fast-forward from the early 20th century to the present day, when technical advances in imaging have revealed any number of the brain’s secrets. Ramón y Cajal would no doubt have marveled at the technicolor neuron maps revealed by the Brainbow labeling technique. (Compare Ramón y Cajal’s drawings of black-stained Purkinje neurons to a Brainbow micrograph of the type of neuron.) But the technical marvels have gotten even more revelatory. © 1986-2017 The Scientist

Keyword: Brain imaging; Development of the Brain
Link ID: 24348 - Posted: 11.24.2017

By Stephani Sutherland When we experience something painful, our brain produces natural painkillers that are chemically similar to potent drugs such as morphine. Now research suggests these endogenous opioids also play another role: helping regulate the body's energy balance. Lauri Nummenmaa, a brain-imaging scientist at the University of Turku in Finland, and his colleagues measured endogenous opioid release in the brains of 10 healthy men. The subjects were injected with a radioactive substance that binds to opioid receptors, making it possible to visualize the receptors' activity using positron-emission tomography. The study found evidence of natural painkillers in the men's brains after they ate a palatable meal of pizza. Surprisingly, their brains released even more of the endogenous opioids after they ate a far less enticing—but nutritionally similar—liquid meal of what Nummenmaa called “nutritional goo.” Although the subjects rated the pizza as tastier than the goo, opioid release did not appear to relate to their enjoyment of the meal, the researchers reported earlier this year in the Journal of Neuroscience. Advertisement “I would've expected the opposite result,” says Paul Burghardt, an investigator at Wayne State University, who was not involved in the work. After all, previous human and animal studies led researchers to believe that endogenous opioids helped to convey the pleasure of eating. Nummenmaa, too, was surprised. His group's earlier research showed that obese people's brains had fewer opioid receptors—but that receptor levels recover with weight loss. “Maybe when people overeat, endogenous opioids released in the brain constantly bombard the receptors, so they [decrease in number],” he says. © 2017 Scientific American

Keyword: Obesity; Attention
Link ID: 24347 - Posted: 11.22.2017

By STEPH YIN Violins, cameras, school desks, computer mouses, can openers — these are just a few items that demonstrate how routinely disadvantaged left-handers are in this world. One notable exception may be sports. Whether it’s Lou Gehrig in baseball, Wayne Gretzky in ice hockey, Martina Navratilova in tennis or Oscar De La Hoya in boxing, some of the best athletes in history have been portsiders. But even in this realm, the southpaw advantage may vary, being more pronounced in sports where a player has less time to react to an opponent, like table tennis, according to Florian Loffing, a sports scientist at the University of Oldenburg in Germany and author of a study published Wednesday in Biology Letters. In such games, he found a higher proportion of lefties than in those with longer intervals between players’ actions. Including an analysis of the pressures of time shows “that there is an additional effect” in left-sider sports dynamics, said Kirsten Legerlotz, a professor of sport sciences at the Humboldt University of Berlin who was not involved in the research. Dr. Loffing’s “conclusion appears convincing,” she added, although it would need to be examined in other sports and verified with lab experiments. Dr. Loffing chose to analyze baseball, cricket, table tennis, badminton, tennis and squash, because they lent themselves to a standardized measure of time pressure, he said. For baseball and cricket, this involved the average time that elapsed between ball release and bat-ball contact in professional games. For the racket sports, he considered the intervals between racket-ball contact made by players in professional matches. He then tallied the number of lefties among each sport’s top 100 players, or pitchers and bowlers in the case of baseball and cricket, from 2009 to 2014. Comparing all six sports against one another, he found the proportion of southpaws increased as the time available for players to act decreased. Nine percent of the top players were left-dominant in the slowest contest, squash, while 30 percent of the best pitchers were lefties in the fastest, baseball. Over all, left-handedness was 2.6 times more likely in the sports with higher time constraints (baseball, cricket and table tennis) than in ones with lower time pressure (badminton, tennis and squash). © 2017 The New York Times Company

Keyword: Laterality
Link ID: 24346 - Posted: 11.22.2017

(Reuters) - Cytokinetics Inc will stop developing one of its treatments for ALS, which afflicts Stephen Hawking, after the drug failed in a late-stage trial, the company said on Tuesday, sending its shares tumbling about 35 percent. The drugmaker said two of the three doses it was testing failed to show a statistically significant difference compared to a placebo when measured by their ability to lower the lungs’ ‘slow vital capacity’, a measure of respiratory function. Amyotrophic lateral sclerosis (ALS), or Lou Gehrig’s disease, is a fatal neuro-degenerative condition that affects nerve cells in the brain and the spinal cord. Deaths and disability in ALS patients are strongly related to respiratory failure, according to Cytokinetics. More than 6,000 people are diagnosed with the disease in the United States every year, according to the ALS Association. ALS garnered international attention in 2014 with the “Ice Bucket Challenge”, which involved people pouring ice-cold water on themselves, posting a video on social media, and donating funds for research on the disease. After the failure of its drug tirasemtiv, Cytokinetics said it will focus on its other ALS treatment, CK-2127107, that it is developing in collaboration with Japan’s Astellas Pharma Inc. Cytokinetics’ chief executive, Robert Blum, said he believes that the limitations of tirasemtiv will be addressed in the development of CK-2127107. © 2017 Business Insider Inc.

Keyword: ALS-Lou Gehrig's Disease
Link ID: 24345 - Posted: 11.22.2017

By JAMES GORMAN and CHRISTOPHER WHITWORTH Cockatoos are smart birds, and the Goffin’s cockatoos in a Vienna lab are among the smartest. In an experiment reported about a year ago, they turned out to be real stars at making tools from a variety of materials in order to get a treat. In a new study, researchers tested the birds’ ability to match shapes using an apparatus reminiscent of a child’s toy. The birds had to put a square tile into a square hole and more complicated, asymmetrical shapes into matching holes. If they were successful, they got a treat. Cornelia Habl, a master’s student at the University of Vienna, and Alice M. I. Auersperg, a researcher at the University of Veterinary Medicine in Vienna, ran several experiments. They reported in the journal PLOS One that the cockatoos were not only able to match the shapes to the holes, but did much better than monkeys or chimpanzees. “It was thought to be an exclusively human ability for a long time,” Ms. Habl said. Tests of matching shapes are used to mark milestones in child development. Babies can put a sphere into the right hole at age 1, but they can’t place a cube until age 2. From there, they continue to improve. Some primates can do similar tasks, although they need a lot of basic training to get up to speed before they can use the experimental apparatus, called a key box. The birds jumped right in without any training and excelled. “Compared to primates, the cockatoos performed very well,” Ms. Habl said. Why are they so good? In the wild, they haven’t been observed using tools. But they are generalists, foragers who take whatever food they can find. They are adaptable enough to do well in some urban areas in Australia, Ms. Habl said. To succeed in a variety of environments eating a variety of foods, “they have to be very, very flexible.” © 2017 The New York Times Company

Keyword: Evolution; Intelligence
Link ID: 24344 - Posted: 11.21.2017

Laura Sanders Around the six-month mark, babies start to get really fun. They’re not walking or talking, but they are probably babbling, grabbing and gumming, and teaching us about their likes and dislikes. I remember this as the time when my girls’ personalities really started making themselves known, which, really, is one of the best parts of raising a kid. After months of staring at those beautiful, bald heads, you start to get a glimpse of what’s going on inside them. When it comes to learning language, it turns out that a lot has already happened inside those baby domes by age 6 months. A new study finds that babies this age understand quite a bit about words — in particular, the relationships between nouns. Work in toddlers, and even adults, reveals that people can struggle with word meanings under difficult circumstances. We might briefly falter with “shoe” when an image of a shoe is shown next to a boot, for instance, but not when the shoe appears next to a hat. But researchers wanted to know how early these sorts of word relationships form. Psychologists Elika Bergelson of Duke University and Richard Aslin, formerly of the University of Rochester in New York and now at Haskins Laboratories in New Haven, Conn., put 51 6-month-olds to a similar test. Outfitted with eye-tracking gear, the babies sat on a parent’s lap and looked at a video screen that showed pairs of common objects. Sometimes the images were closely related: mouth and nose, for instance, or bottle and spoon. Other pairs were unrelated: blanket and dog, or juice and car. © Society for Science and the Public

Keyword: Language; Development of the Brain
Link ID: 24343 - Posted: 11.21.2017

Tania Lombrozo In The Devil's Dictionary, Ambrose Bierce describes the mind as "a mysterious form of matter secreted by the brain," engaged in a futile attempt to understand itself "with nothing but itself to know itself with." Questions about the limits of self-understanding have persisted long after Bierce's 1911 publication. One user on Quora asks: "Is the human brain intelligent enough to fully understand itself?" A satirical headline at The Onion reports that psychology has come to a halt as "weary researchers say the mind cannot possibly study itself." Despite such doubts, the science of the mind has made enormous advances over the last century. Yet many questions remain, along with the more foundational worry that motivated Bierce. Are there fundamental limits to what science can explain about the human mind? Can science truly explain consciousness and love, morality and religious belief? And why do topics like these seem especially ineffable — further beyond the scope of scientific explanation than more mundane psychological phenomena, such as forgetting a name or recognizing a face? Psychology PhD student Sara Gottlieb and I decided to find out. In a series of studies forthcoming in the journal Psychological Science, we asked hundreds of participants to tell us whether they thought it was possible for science to one day fully explain various aspects of the human mind, from depth perception and memory loss to spirituality and romantic love. © 2017 npr

Keyword: Miscellaneous
Link ID: 24342 - Posted: 11.21.2017

Sara Reardon When it comes to lab mice and antidepressants, it's complicated. Mouse experiments with the popular club drug ketamine may be skewed by the sex of the researcher performing them, a study suggests. The findings, presented on 14 November at the Society for Neuroscience (SfN) meeting in Washington DC, only deepen the mystery of how ketamine, which has powerful mood-lifting properties, interacts with the brain. They also raise questions about the reproducibility of behavioural experiments in mice. Ketamine is best known as a psychoactive recreational drug. But it has caught psychiatrists’ interest because of its potential to treat depression within hours. It’s unclear exactly how the drug works, however, and many researchers are using animal models to suss out the mechanism. Polymnia Georgiou, a neuroscientist at the University of Maryland in Baltimore, is one of them. In 2015, a male colleague asked her to run some experiments for him while he was out of town, including a standard way of testing antidepressants called the forced-swim test. In this assay, researchers inject healthy mice with a drug, place them into a tank of water and measure how long they swim before they give up and wait for someone to rescue them. Antidepressants can cause healthy mice to swim for longer than their untreated counterparts, which is what Georgiou’s male colleague found during his experiments using ketamine. © 2017 Macmillan Publishers Limited

Keyword: Sexual Behavior; Depression
Link ID: 24341 - Posted: 11.20.2017

By Bahar Gholipour, The same techniques that generate images of smoke, clouds and fantastic beasts in movies can render neurons and brain structures in fine-grained detail. Two projects presented yesterday at the 2017 Society for Neuroscience annual meeting in Washington, D.C., gave attendees a sampling of what these powerful technologies can do. “These are the same rendering techniques that are used to make graphics for ‘Harry Potter’ movies,” says Tyler Ard, a neuroscientist in Arthur Toga’s lab at the University of Southern California in Los Angeles. Ard presented the results of applying these techniques to magnetic resonance imaging (MRI) scans. The methods can turn massive amounts of data into images, making them ideally suited to generate brain scans. Ard and his colleagues develop code that enables them to easily enter data into the software. They plan to make the code freely available to other researchers. The team is also combining the visualization software with virtual reality to enable scientists to explore the brain in three dimensions, and even perform virtual dissections of the brain. In one demo, the user can pick at a colored, segmented brain that can be pulled apart like pieces of Lego. “This can be useful when learning neuroanatomy,” Ard says. “The way that I learned it, we had to look at slices, and that’s real hard. This is a way that allows you to understand 3-D structure better.” The team plans to release the program, called Neuro Imaging in Virtual Reality, online next year. © 2017 Scientific American

Keyword: Brain imaging
Link ID: 24340 - Posted: 11.20.2017

In the fight against brain damage caused by stroke, researchers have turned to an unlikely source of inspiration: hibernating ground squirrels. While the animals’ brains experience dramatically reduced blood flow during hibernation, just like human patients after a certain type of stroke, the squirrels emerge from their extended naps suffering no ill effects. Now, a team of NIH-funded scientists has identified a potential drug that could grant the same resilience to the brains of ischemic stroke patients by mimicking the cellular changes that protect the brains of those animals. The study was published in The FASEB Journal, the official journal of the Foundation of American Societies for Experimental Biology. “For decades scientists have been searching for an effective brain-protecting stroke therapy to no avail. If the compound identified in this study successfully reduces tissue death and improves recovery in further experiments, it could lead to new approaches for preserving brain cells after an ischemic stroke,” said Francesca Bosetti, Ph.D., Pharm.D., program director at the NIH’s National Institute of Neurological Disorders and Stroke (NINDS). An ischemic stroke occurs when a clot cuts off blood flow to part of the brain, depriving those cells of oxygen and nutrients like the blood sugar glucose that they need to survive. Nearly 800,000 Americans experience a stroke every year and 87 percent of those are ischemic strokes. Currently, the only way to minimize stroke-induced cell death is to remove the clot as soon as possible. A treatment to help brain cells survive a stroke-induced lack of oxygen and glucose could dramatically improve patient outcomes, but no such neuroprotective agents for stroke patients exist.

Keyword: Stroke
Link ID: 24339 - Posted: 11.20.2017

By NIRAJ CHOKSHI The Rev. Jesse L. Jackson, the longtime civil rights leader and former Democratic presidential candidate, said Friday he has Parkinson’s disease. In a letter posted on Twitter on Friday afternoon, Mr. Jackson, 76, shared the news and his struggle to accept it. “Recognition of the effects of this disease on me has been painful, and I have been slow to grasp the gravity of it,” he wrote. “For me, a Parkinson’s diagnosis is not a stop sign but rather a signal that I must make lifestyle changes and dedicate myself to physical therapy in hopes of slowing the disease’s progression.” Parkinson’s is a movement disorder. Its symptoms include muscle tremors and stiffness and poor balance and coordination. It typically begins after age 50 and can cause difficulty sleeping, chewing, swallowing or speaking. Mr. Jackson has been a civil rights advocate for 50 years and sought the Democratic presidential nominations in 1984 and 1988. He was also a close associate of the Rev. Dr. Martin Luther King Jr. Mr. Jackson wrote that he and his family about three years ago began to notice he was having increasing difficulty performing routine tasks and was initially reluctant to see doctors. He said he saw the diagnosis as “an opportunity” to use his platform to advocate a cure and said that he would not let it disrupt his other advocacy. “I will continue to try to instill hope in the hopeless, expand our democracy to the disenfranchised and free innocent prisoners around the world,” he wrote. © 2017 The New York Times Company

Keyword: Parkinsons
Link ID: 24338 - Posted: 11.20.2017

By Meredith Wadman When people die from overdoses of opioids, whether prescription pain medications or street drugs, it is the suppression of breathing that almost always kills them. The drugs act on neuronal receptors to dull pain, but those in the brain stem also control breathing. When activated, they can signal respiration to slow, and then stop. The results are well-known: an epidemic of deaths—about 64,000 people in the United States alone last year. Countering this lethal side effect without losing opioids' potent pain relief is a challenge that has enticed drug developers for years. Now, for the first time, the U.S. Food and Drug Administration (FDA) in Silver Spring, Maryland, is considering whether to approve an opioid that is as effective as morphine at relieving pain and poses less risk of depressing breathing. Trevena, a firm based in Chesterbrook, Pennsylvania, announced on 2 November that it has submitted oliceridine, an intravenous opioid meant for use in hospitalized patients, to FDA for marketing approval. The drug, which would be marketed under the name Olinvo, is the most advanced of what scientists predict will be a growing crop of pain-relieving "biased agonists"—so called because, in binding a key opioid receptor in the central nervous system, they nudge it into a conformation that promotes a signaling cascade that kills pain over one that suppresses breathing. And in a paper out this week in Cell, a veteran opioid researcher and her colleagues unveil new biased opioid agonists that could surpass oliceridine, though they haven't been tested in people yet. "There are many groups creating [such] biased agonists. And one of them is going to get it right," says Bryan Roth, a molecular pharmacologist at the University of North Carolina in Chapel Hill. "To have a drug you can't die of an overdose with would be a huge lifesaver for tens of thousands of people every year." © 2017 American Association for the Advancement of Science.

Keyword: Drug Abuse; Pain & Touch
Link ID: 24337 - Posted: 11.17.2017

By Jennifer Couzin-Frankel Rachel Loewy was an undergraduate in 1995 when she answered a flyer seeking students to assist with a research study. A couple of floors up in a psychology department building, Loewy sat, clipboard in hand, interviewing teenagers whose brain health was beginning to falter. Some heard whispers. Others imagined that their teachers could read their minds, or that fellow students stared at them and wished them harm as they walked down the halls. The teenagers had been diagnosed with schizotypal personality disorder, a condition that can precede schizophrenia. Among the most debilitating and stigmatized psychiatric diseases, schizophrenia can rob sufferers of their self and their future, often in early adulthood. Although these teens didn't have schizophrenia, the researchers believed that some would later deteriorate and be diagnosed with the disorder. But when Loewy met them they were lucid and self-aware. And they were frightened that their mind sometimes spun out of control. Doctors routinely assess a patient's risk of heart attack, various cancers, and diabetes, often intervening to slow or stop disease before it strikes. But preventing psychiatric conditions, from anxiety to depression to schizophrenia, has received scant attention. © 2017 American Association for the Advancement of Science

Keyword: Schizophrenia
Link ID: 24336 - Posted: 11.17.2017

By RONI CARYN RABIN A. Parkinsonism refers to a group of movement abnormalities — such as stiffness, slowness, shuffling of the feet and often tremor — that are classic features of Parkinson’s disease but that can also be caused by medications and other disorders with overlapping symptoms, said Dr. Michael S. Okun, a neurologist and the national medical director of the Parkinson’s Foundation. He said that he makes no assumptions about the cause of parkinsonism “until I see the patient and pinpoint the diagnosis.” Determining the cause of parkinsonism involves asking a series of questions, starting with, “Do we think this is regular Parkinson’s disease?” said Dr. Okun, who is also co-director of the Center for Movement Disorders and Neurorestoration at the University of Florida College of Medicine in Gainesville. Though a diagnosis of Parkinson’s disease strikes fear in patients, Dr. Okun said that the illness, a neurodegenerative brain disorder caused by the loss of dopamine-containing neurons and other cells, progresses slowly in many people and generally responds well to drugs that replenish dopamine in the brain. Some patients whose parkinsonism is not caused by Parkinson’s disease also respond to these drugs, but the medications are most effective for people with Parkinson’s disease, Dr. Okun said. It’s important to rule out other potential causes of parkinsonism, he said. The condition can be triggered by antipsychotic medications that affect dopamine levels in the brain, as well as by other drugs, including stimulants like amphetamines and cocaine. Discontinuing the drugs may stop the symptoms over time, though not always. Parkinsonism may also be caused by repeated injuries to the head, exposure to various toxins or brain lesions. Once doctors rule out Parkinson’s disease, they must consider several other serious neurological disorders. The three most common ones are multiple system atrophy, a degenerative disorder also referred to as Shy-Drager syndrome, which may or may not respond well to Parkinson’s medications; progressive supranuclear palsy, or PSP, which also may respond to high doses of drugs that replace dopamine in the brain; and corticobasal degeneration (CBD). Patients with a form of dementia called Lewy body dementia may also exhibit symptoms of parkinsonism, which may or may not respond to dopamine. Various other movement disorders, called ataxias or dystonias, also may display features of parkinsonism. © 2017 The New York Times Company

Keyword: Parkinsons
Link ID: 24335 - Posted: 11.17.2017

Laura Sanders In stark contrast to earlier findings, adults do not produce new nerve cells in a brain area important to memory and navigation, scientists conclude after scrutinizing 54 human brains spanning the age spectrum. The finding is preliminary. But if confirmed, it would overturn the widely accepted and potentially powerful idea that in people, the memory-related hippocampus constantly churns out new neurons in adulthood. Adult brains showed no signs of such turnover in that region, researchers reported November 13 at a meeting of the Society for Neuroscience in Washington, D.C. Previous studies in animals have hinted that boosting the birthrate of new neurons, a process called neurogenesis, in the hippocampus might enhance memory or learning abilities, combat depression and even stave off the mental decline that comes with dementia and old age (SN: 9/27/08, p. 5). In rodents, exercise, enriched environments and other tweaks can boost hippocampal neurogenesis — and more excitingly, memory performance. But the new study may temper those ambitions, at least for people. Researchers studied 54 human brain samples that ranged from fetal stages to age 77, acquired either postmortem or during brain surgery. These samples were cut into thin slices and probed with molecular tools that can signal dividing or young cells, both of which are signs that nerve cells are being born. As expected, fetal and infant samples showed evidence of both dividing cells that give rise to new neurons and young neurons themselves in the hippocampus. But with age, these numbers declined. In brain tissue from a 13-year-old, the researchers spotted only a handful of young neurons. And in adults, there were none. |© Society for Science & the Public 2000 - 2017.

Keyword: Neurogenesis
Link ID: 24334 - Posted: 11.16.2017