Chapter 16. None

Follow us on Facebook and Twitter, or subscribe to our mailing list, to receive news updates. Learn more.


Links 61 - 80 of 2203

By LISA FELDMAN BARRETT OUR senses appear to show us the world the way it truly is, but they are easily deceived. For example, if you listen to a recorded symphony through stereo speakers that are placed exactly right, the orchestra will sound like it’s inside your head. Obviously that isn’t the case. But suppose you completely trusted your senses. You might find yourself asking well-meaning but preposterous scientific questions like “Where in the brain is the woodwinds section located?” A more reasonable approach is not to ask a where question but a how question: How does the brain construct this experience of hearing the orchestra in your head? I have just set the stage to dispel a major misconception about emotions. Most people, including many scientists, believe that emotions are distinct, locatable entities inside us — but they’re not. Searching for emotions in this form is as misguided as looking for cerebral clarinets and oboes. Of course, we experience anger, happiness, surprise and other emotions as clear and identifiable states of being. This seems to imply that each emotion has an underlying property or “essence” in the brain or body. Perhaps an annoying co-worker triggers your “anger neurons,” so your blood pressure rises; you scowl, yell and feel the heat of fury. Or the loss of a loved one triggers your “sadness neurons,” so your stomach aches; you pout, feel despair and cry. Or an alarming news story triggers your “fear neurons,” so your heart races; you freeze and feel a flash of dread. Such characteristics are thought to be the unique biological “fingerprints” of each emotion. Scientists and technology companies spend enormous amounts of time and money trying to locate these fingerprints. They hope someday to identify your emotions from your facial muscle movements, your body changes and your brain’s electrical signals. © 2015 The New York Times Company

Keyword: Emotions
Link ID: 21254 - Posted: 08.02.2015

Teresa Shipley Feldhausen Move over, umami. Fat is the newest member of the pantheon of basic tastes, joining salty, sweet, sour, bitter and savory, or umami. Researchers at Purdue University in West Lafayette, Ind., conducted taste tests pitting a variety of fats against flavors in the other taste categories, such as monosodium glutamate for umami. The result: People recognize some fats as separate from the other five taste categories, even with plugged noses. The researchers dub this sixth sense oleogustus. For instance, nearly two-thirds of tasters identified one type of fat — linoleic acid, found in vegetable and nut oils — as a distinct flavor. Texture wasn’t a factor; the researchers whipped up tasting samples that gave the same mouthfeel. Pure oleogustus doesn’t invoke notes of olive oil or fresh butter. It’s unpleasant, the researchers report online July 3 in Chemical Senses. Mix oleogustus with some of the other five flavors, however, and you could end up with doughnuts or potato chips. Citations C.A. Running, B.A. Craig and R.D. Mattes. Oleogustus: The unique taste of fat. Chemical Senses. Published online July 3, 2015. doi: 10.1093/chemse/bjv036. © Society for Science & the Public 2000 - 2015.

Keyword: Chemical Senses (Smell & Taste)
Link ID: 21252 - Posted: 08.02.2015

By Gary Stix A decline in hearing acuity is not only an occurrence that happens in the aged. An article in the August Scientific American by M. Charles Liberman, a professor of otology and laryngology at Harvard Medical School and director of the Eaton-Peabody Laboratories at Massachusetts Eye and Ear, focuses on relatively recent discoveries that show the din of a concert or high-decibel machine noise is enough to cause some level of hearing damage. After reading the article check out this video by medical illustrator Brandon Pletsch and its narrated animation explaining how the sensory system that detects sound functions. © 2015 Scientific American

Keyword: Hearing
Link ID: 21250 - Posted: 08.02.2015

Alison Abbott Six years might seem like a long time to spend piecing together the structure of a scrap of tissue vastly smaller than a bead of sweat. But that is how long it has taken a team led by cell biologist Jeff Lichtman from Harvard University in Cambridge, Massachusetts, to digitally reconstruct a tiny cube of mouse brain tissue. The resulting three-dimensional map1 is the first complete reconstruction of a piece of tissue in the mammalian neocortex, the most recently evolved region of the brain. Covering just 1,500 cubic microns, it is still a far cry from reconstructing all 100 billion or so cells that make up the entire human brain. But Christof Koch, president of the Allen Institute for Brain Science in Seattle, Washington, notes that the various technologies involved will speed up “tremendously” over the next decade: “I would call this a very exciting promissory note,” he says. Lichtman’s team already has its eyes on a much bigger challenge: reconstructing a cubic millimetre of rodent neocortex — a piece of tissue around 600,000 times larger than the present achievement. The researchers will be doing this as part of a consortium that earlier this month received preliminary approval for major funding by the US government agency IARPA (Intelligence Advanced Research Projects Activity), which promotes high-risk, high pay-off research. The goal of the consortium, based at Harvard and at the Massachusetts Institute of Technology (MIT) in Cambridge, is to map the function as well as the anatomy of this tiny brain volume, while also working out how it computes information as an animal learns. © 2015 Nature Publishing Group,

Keyword: Brain imaging
Link ID: 21249 - Posted: 08.01.2015

Kill, Fido! Docile ants become aggressive guard dogs after a secret signal from their caterpillar overlord. The idea turns on its head the assumption that the two species exchange favours in an even-handed relationship. The caterpillars of the Japanese oakblue butterfly (Narathura japonica) grow up wrapped inside leaves on oak trees. To protect themselves against predators like spiders and wasps, they attract ant bodyguards, Pristomyrmex punctatus, with an offering of sugar droplets. The relationships was thought to be a fair exchange of services in which both parties benefit. But Masaru Hojo from Kobe University in Japan noticed something peculiar: the caterpillars were always attended by the same ant individuals. “It also seemed that the ants never moved away or returned to their nests,” he says. They seemed to abandon searching for food, and were just standing around guarding the caterpillar. Intrigued, Hojo and his colleagues conducted lab experiments in which they allowed some ants to interact with the caterpillars and feed on the secretions, and kept others separate. Ants that ate the caterpillar’s secretions remained close to the caterpillar. They didn’t return to their nest. And whenever the caterpillar everted its tentacles – flipped them so they turned inside out – the ants moved around rapidly, acting aggressively. © Copyright Reed Business Information Ltd.

Keyword: Evolution; Drug Abuse
Link ID: 21244 - Posted: 08.01.2015

Five men with complete motor paralysis were able to voluntarily generate step-like movements thanks to a new strategy that non-invasively delivers electrical stimulation to their spinal cords, according to a new study funded in part by the National Institutes of Health. The strategy, called transcutaneous stimulation, delivers electrical current to the spinal cord by way of electrodes strategically placed on the skin of the lower back. This expands to nine the number of completely paralyzed individuals who have achieved voluntary movement while receiving spinal stimulation, though this is the first time the stimulation was delivered non-invasively. Previously it was delivered via an electrical stimulation device surgically implanted on the spinal cord. In the study, the men’s movements occurred while their legs were suspended in braces that hung from the ceiling, allowing them to move freely without resistance from gravity. Movement in this environment is not comparable to walking; nevertheless, the results signal significant progress towards the eventual goal of developing a therapy for a wide range of individuals with spinal cord injury. “These encouraging results provide continued evidence that spinal cord injury may no longer mean a life-long sentence of paralysis and support the need for more research,” said Roderic Pettigrew, Ph.D., M.D., director of the National Institute of Biomedical Imaging and Bioengineering at NIH. “The potential to offer a life-changing therapy to patients without requiring surgery would be a major advance; it could greatly expand the number of individuals who might benefit from spinal stimulation. It’s a wonderful example of the power that comes from combining advances in basic biological research with technological innovation.”

Keyword: Robotics
Link ID: 21242 - Posted: 08.01.2015

By JESSE McKINLEY ALBANY — In a case watched by animal rights activists and courtroom curiosity seekers, a State Supreme Court judge in Manhattan on Thursday denied a request to free a pair of chimpanzees, Hercules and Leo, being held at a state university on Long Island. The unorthodox petition — which sought a writ of habeas corpus, an age-old method of challenging unlawful imprisonment — was the latest attempt by the nonprofit Nonhuman Rights Project to establish that apes are “legal persons.” The group argues that chimps are self-aware and autonomous, a contention it has supported by submitting affidavits attesting to the animals’ intelligence, language skills and personalities, among other traits, in several cases filed in New York on behalf of various imprisoned primates. In what the group hoped was a positive sign, Justice Barbara Jaffe of State Supreme Court in April ordered a hearing on whether Hercules and Leo, 8-year-old apes living as research subjects at the State University of New York at Stony Brook, could be released and transferred to an animal sanctuary in Florida. Arguments were heard in late May. But while Justice Jaffe took the case seriously — her 33-page decision cited the long history of habeas corpus and included references to discrimination against women and African-American slaves — she could not quite see Hercules and Leo as people in the eyes of the law. “For the purpose of establishing rights, the law presently categorizes entities in a simple, binary, ‘all or nothing,’ fashion,” the justice wrote, noting: “Persons have rights, duties, and obligations. Things do not.” “Animals, including chimpanzees and other highly intelligent mammals, are considered property under the law,” she continued. “They are accorded no legal rights,” beyond being free from mistreatment or abuse. © 2015 The New York Times Company

Keyword: Animal Rights
Link ID: 21241 - Posted: 07.31.2015

Ewen Callaway Our ancestors were not a picky bunch. Overwhelming genetic evidence shows that Homo sapiens had sex with Neander­thals, Denisovans and other archaic relatives. Now researchers are using large genomics studies to unravel the decidedly mixed contributions that these ancient romps made to human biology — from the ability of H. sapiens to cope with environments outside Africa, to the tendency of modern humans to get asthma, skin diseases and maybe even depression. The proportion of the human genome that comes from archaic relatives is small. The genomes of most Europeans and Asians are 2–4% Neanderthal1, with Denisovan DNA making up about 5% of the genomes of Mela­nesians2 and Aboriginal Australians3. DNA slivers from other distant relatives probably pepper a variety of human genomes4. But these sequences may have had an outsize effect on human biology. In some cases, they are very different from the corresponding H. sapiens DNA, notes population geneticist David Reich of Harvard Medical School in Boston, Massachusetts — which makes it more likely that they could introduce useful traits. “Even though it’s only a couple or a few per cent of ancestry, that ancestry was sufficiently distant that it punched above its weight,” he says. Last year, Reich co-led one of two teams that catalogued the Neanderthal DNA living on in modern-day humans5, 6. The studies hinted that Neanderthal versions of some genes may have helped Eurasians to reduce heat loss or grow thicker hair. But the evidence that these genes were beneficial was fairly weak. To get a better handle on how Neanderthal DNA shapes human biology, Corinne Simonti and Tony Capra, evolutionary geneticists at Vanderbilt University in Nashville, Tennessee, turned to genome-wide association studies (GWAS) that had already compared thousands of DNA variants in people with and without a certain disease or condition. © 2015 Nature Publishing Group,

Keyword: Evolution
Link ID: 21240 - Posted: 07.30.2015

By Katie Free Shouting during a nightmare. Struggling to balance a checkbook. A weakened sense of smell. Hallucinations. Chronic constipation. This bizarre mix of symptoms often stumps doctors, but they are some of the telltale signs of Lewy body dementia—the second most common type (after Alzheimer's disease), affecting an estimated 1.4 million Americans. Lewy bodies are protein clumps that kill neurons. Depending on where they cluster in the brain, they can cause either Parkinson's disease or Lewy body dementia, although the two conditions tend to overlap as they progress. Lewy body dementia is more difficult to diagnose and treat, in part because the earliest warning signs have remained unknown. Now a new study finds that certain sensory and motor symptoms can help predict who will acquire the disease, paving the way for targeted studies. Researchers at the Center for Advanced Research in Sleep Medicine (which is associated with the University of Montreal) and at McGill University followed 89 patients with a history of acting out their dreams—not sleepwalking but moving or vocalizing in bed during rapid eye movement (REM) sleep. The failure to suppress such nighttime activity can be an early sign that something is going wrong in the brain; past studies have shown that up to 80 percent of patients who act out their dreams will eventually develop some form of neurodegeneration. Over 10 years the McGill researchers carefully tracked the patients' other potential symptoms of neural disease, such as mild cognitive impairment, depression and movement problems. They found a cluster of symptoms—abnormal color vision, loss of smell and motor dysfunction—that doubled the chance that a person with the REM sleep disorder would develop Parkinson's or Lewy body dementia within three years, according to the study published in February in Neurology. © 2015 Scientific American

Keyword: Alzheimers
Link ID: 21237 - Posted: 07.30.2015

By Sophia Kercher As Kathleen Emmets was undergoing cancer treatment in New York over the past few years, her weight began to drop. Even though she was often nauseated and paralyzed by chemotherapy-induced neuropathy, she joked that thinness was the “bonus of cancer,” and found herself looking in the mirror and admiring her deep and hollow collarbone. Ms. Emmets, now 39, filled her closet with extra-small size clothes. At night she pressed her fingers against her protruding bones, saying to herself, “I’m finally skinny.” But it was only when her cancer treatment changed that it became clear that the body-image issues she had been grappling with since her early 20s — when she would eat next to nothing and walk for six hours a day to deal with stress — had begun to resurface. When the new treatment didn’t make her sick, her appetite returned, and she began to gain weight. But instead of celebrating this sign of improving health, Ms. Emmets says she missed her size 2 jeans and was appalled by her round belly and full breasts. Her husband watched with concern as her body appeared stronger but she began imposing her own food restrictions and started shrinking again. “During your cancer treatment, you have no control over your body — you give up your body to your doctor,” said Ms. Emmets, who wrote about her experiences on the website The Manifest-Station. “You are willing to do it because you want to live. Food restriction is the one thing that you can do to have some sense of control when everything is chaotic.” While it isn’t known how often cancer triggers or reawakens an eating disorder, doctors and nutrition experts who work with cancer patients share anecdotal reports of patients who emerge from a difficult round of cancer treatment and weight loss only to begin struggling with a serious eating disorder that threatens their postcancer health. © 2015 The New York Times Company

Keyword: Anorexia & Bulimia
Link ID: 21236 - Posted: 07.30.2015

by Anil Ananthaswamy Science journalist Anil Ananthaswamy thinks a lot about "self" — not necessarily himself, but the role the brain plays in our notions of self and existence. In his new book, The Man Who Wasn't There, Ananthaswamy examines the ways people think of themselves and how those perceptions can be distorted by brain conditions, such as Alzheimer's disease, Cotard's syndrome and body integrity identity disorder, or BIID, a psychological condition in which a patient perceives that a body part is not his own. Ananthaswamy tells Fresh Air's Terry Gross about a patient with BIID who became so convinced that a healthy leg wasn't his own that he eventually underwent an amputation of the limb. "Within 12 hours, this patient that I saw, he was sitting up and there was no regret. He really seemed fine with having given up his leg," Ananthaswamy says. Ultimately, Ananthaswamy says, our sense of self is a layered one, which pulls information from varying parts of the brain to create a sense of narrative self, bodily self and spiritual self: "What it comes down to is this sense we have of being someone or something to which things are happening. It's there when we wake up in the morning, it kind of disappears when we go to sleep, it reappears in our dreams, and it's also this sense we have of being an entity that spans time." Interview Highlights On how to define "self" When you ask someone, "Who are you?" you're most likely to get a kind of narrative answer, "I am so-and-so, I'm a father, I'm son." They are going to tell you a kind of story they have in their heads about themselves, the story that they tell to themselves and to others, and in some sense that's what can be called the narrative self. ... © 2015 NPR

Keyword: Attention
Link ID: 21235 - Posted: 07.29.2015

By Emily Underwood My childhood hamster, Hamlet, seemed pretty depressed. He didn’t seem to enjoy his colorful cage, complete with a tunnel, wheel, and ramp. The only thing he did with zest was gnaw at the plastic, trying to escape, which he eventually did. A few days later, my mother found him lying on the bathroom floor, dead. I have wondered ever since: Was Hamlet suicidal? Or was he simply displaying normal hamster behavior? Now, a new study suggests a scientific method for gauging hamsters’ emotional states. Hamster emotions don’t just baffle pet owners; they also bedevil scientists who use the fluffballs as subjects in their experiments. One of the most frustrating things about trying to study animal emotion in general is that you can’t take behaviors at face value. If a hamster runs madly on its wheel all night, for example, how do you know if it is running out of joy, or boredom? (Or just for the heck of it.) To bypass that problem, the researchers decided to measure something called judgment bias—essentially, the way that mood affects behavior and decision-making. As humans, our decisions are influenced by our emotions all the time—witness stress-eating, or revenge-shopping. Similar biases have been found in primates, rats, mice, and many other animals, but never before in hamsters. In the experiment, researchers split 30 Syrian hamsters into two groups. One group lived the high life, in cages bedecked with extra toys, ramps, bedding, and hammocks. The second group had the minimum in hamster hospitality, with some light bedding and a wheel. © 2015 American Association for the Advancement of Science.

Keyword: Emotions
Link ID: 21234 - Posted: 07.29.2015

The eyes may be windows to the mind, but for children with autism, the body is the better communicator. They are just as good at reading emotions in body language as those without autism. The finding challenges the commonly held notion that children with autism have difficulty reading emotions. This may have arisen from studies focusing on whether people with the condition can interpret emotions from just the face or eyes, says Candida Peterson at the University of Queensland in Australia. “Looking at a face is in itself a problem,” says Peterson. “Autistic children and adults don’t like making eye contact,” she adds, as this requires a close encounter with another person. Reading body language, by contrast, can be done from a distance. In the study, children aged 5 to 12 were shown photos of adults with blurred faces posing in ways to convey happiness, sadness, anger, fear, disgust and surprise. Those with autism were just as good as those without at recognising the emotions. But this is only part of the picture. People with autism also have difficulty changing their behaviour in response to others’ emotions, says Julie Grezes at INSERM’s Laboratory of Cognitive Neurosciences in Paris, France. When most people recognise that someone is experiencing a certain emotion, they are able to put themselves in their place to understand why they might be feeling that way. People with autism are known to struggle with this. Now we know that they can read body language, says Peterson, we can look for ways to help them link certain cues to what the other person might be thinking and feeling. She and her colleagues now plan to test how good children with autism are at reading body language cues in real-life interactions, in particular when they are faced with individuals in extremely emotional states. Journal reference: Journal of Experimental Child Psychology, doi.org/6dp © Copyright Reed Business Information Ltd.

Keyword: Autism
Link ID: 21225 - Posted: 07.27.2015

By Karen Weintraub Can I ever re-pay my sleep debt? (I estimate it at 15 years of poor sleep.) It is unclear whether you can make up a long-term sleep debt, because most studies have looked at the effects of sleep loss and recovery only over a few nights or weeks, said Dr. Matt T. Bianchi, the chief of the division of sleep medicine at Massachusetts General Hospital and an assistant professor of neurology at Harvard Medical School. Simulated driving performance and reaction times are affected by just one sleepless night, research has shown. There’s no doubt that sleeping just four hours a night catches up to people within a few nights, leading to impairments of attention, learning and memory and worse performance in school and at work. And making up for lost sleep over the weekend doesn’t work. Five brief nights quickly add up to a shortfall of 20 hours, but people don’t sleep more than five to 10 extra hours to compensate, Dr. Bianchi said. “The interpretation has been you can’t pay off your sleep debt, you just carry it with you,” though it’s also possible that people don’t sleep an extra 20 hours because they don’t need it, Dr. Bianchi said. He cited research by Jim Horne of Loughborough University in Britain showing that a timely nap of less than 20 minutes can equate to an extra hour of nighttime sleep. Different people need somewhat different amounts of sleep, but anything less than six hours a night is definitely not enough, said Dr. Charles Czeisler, a professor of sleep medicine at Harvard. In one sleep study, people were brought into a lab and required to stay in bed for 14 hours a day. They slept 10 to 12 hours a night at first, Dr. Czeisler said. Then they gradually slept less over the next few weeks until they stabilized at about 8.4 hours per night. © 2015 The New York Times Company

Keyword: Sleep
Link ID: 21223 - Posted: 07.27.2015

By Claire Asher City folk have a reputation for being less friendly than their rural counterparts, and the same appears to be true for garden birds. Urban song sparrows (Melospiza melodia, pictured) are more aggressive toward their neighbors than are sparrows out in the country, researchers report this month in Behavioral Ecology. But whereras the temperament of human city-dwellers is often attributed to the sheer density of people, this isn’t the case for sparrows. The team measured birds’ responses to recordings of another male’s song, noting how often males approached or attacked the speakers, and found that aggression depended not on the density of sparrows, but on the availability of food in the environment. Counterintuitively, male sparrows responded more aggressively in the city, where there tends to be more food, and rural birds became more aggressive when provided with food supplements. The authors explain that the sparrows defend food-rich, high-quality territories more aggressively, but it isn’t clear whether this is an offensive or a defensive strategy; city birds may be more aggressive because a territory with more food is more valuable to them, or because their abundant resources attract more thieves. © 2015 American Association for the Advancement of Science.

Keyword: Aggression
Link ID: 21221 - Posted: 07.27.2015

Alison Abbott Neuroscientists have identified an area of the brain that might give the human mind its unique abilities, including language. The area lit up in human, but not monkey, brains when they were presented with different types of abstract information. The idea that integrating abstract information drives many of the human brain's unique abilities has been around for decades. But a paper published1 in Current Biology, which directly compares activity in human and macaque monkey brains as they listen to simple auditory patterns, provides the first physical evidence that a specific area for such integration may exist in humans. Other studies that compare monkeys and humans have revealed differences in the brain’s anatomy, for example, but not differences that could explain where humans’ abstract abilities come from, say neuroscientists. “This gives us a powerful clue about what is special about our minds,” says psychologist Gary Marcus at New York University. “Nothing is more important than understanding how we got to be how we are.” A team of researchers headed by Stanislas Dehaene at the INSERM Cognitive Neuroimaging Unit at Gif-sur-Yvette near Paris, looked at changing patterns of activation in the brain as untrained monkeys and human adults listened to a simple sequence of tones, for example three identical tones followed by a different tone (like the famous four-note opening of Beethoven’s fifth symphony: da-da-da-DAH). The researchers played several different sequences with this structure — known as AAAB — and other sequences to the subjects while they lay in a functional magnetic resonance imaging (fMRI) scanner. The fMRI technique picks up changes in blood flow in the brain that correlate with regional brain activity. © 2015 Nature Publishing Group,

Keyword: Attention; Evolution
Link ID: 21220 - Posted: 07.25.2015

A panel of independent experts has decided that a clot-busting drug often used to treat strokes is "safe and effective". The UK medicines watchdog wanted the benefits and risks of alteplase to be analysed after concerns were raised about its safety. The panel concluded that the best time to use the drug is up to four and a half hours after the start of symptoms. But some other doctors are still not convinced by the evidence. Most strokes are caused by a clot blocking the flow of blood to the brain. Many patients are given the drug alteplase to break down and disperse the clot - a treatment known as thrombolysis. The independent expert panel, chaired by Prof Sir Ian Weller, said it had looked at all available data on alteplase and decided that the earlier the drug was given to patients, the greater the chance of a good outcome. Used up to four and a half hours after the onset of symptoms, the benefits of the drug were found to outweigh the risks. But it added that the benefits of using alteplase to treat strokes were "highly time-dependent" and, in a small number of people, there was a risk of haemorrhage. Prof Weller explained: "The evidence shows that for every 100 patients treated with alteplase, whilst there is an early risk of a fatal bleed in two patients, after three to six months, around 10 more in every 100 are disability-free when treated within three hours." © 2015 BBC.

Keyword: Stroke
Link ID: 21218 - Posted: 07.25.2015

By Karen Weintraub Can I ever re-pay my sleep debt? (I estimate it at 15 years of poor sleep.) It is unclear whether you can make up a long-term sleep debt, because most studies have looked at the effects of sleep loss and recovery only over a few nights or weeks, said Dr. Matt T. Bianchi, the chief of the division of sleep medicine at Massachusetts General Hospital and an assistant professor of neurology at Harvard Medical School. Simulated driving performance and reaction times are affected by just one sleepless night, research has shown. There’s no doubt that sleeping just four hours a night catches up to people within a few nights, leading to impairments of attention, learning and memory and worse performance in school and at work. And making up for lost sleep over the weekend doesn’t work. Five brief nights quickly add up to a shortfall of 20 hours, but people don’t sleep more than five to 10 extra hours to compensate, Dr. Bianchi said. “The interpretation has been you can’t pay off your sleep debt, you just carry it with you,” though it’s also possible that people don’t sleep an extra 20 hours because they don’t need it, Dr. Bianchi said. He cited research by Jim Horne of Loughborough University in Britain showing that a timely nap of less than 20 minutes can equate to an extra hour of nighttime sleep. Different people need somewhat different amounts of sleep, but anything less than six hours a night is definitely not enough, said Dr. Charles Czeisler, a professor of sleep medicine at Harvard. © 2015 The New York Times Company

Keyword: Sleep
Link ID: 21214 - Posted: 07.25.2015

By Annick Laurent Can you tell a pygmy blue whale from an Antarctic blue whale? If not, you aren’t alone. Marine biologists have had trouble distinguishing these enormous mammals with mottled skin patterns ever since they began studying them—and that has complicated efforts to figure out where they breed and how to best protect them. Now, researchers have caught a break thanks to a pygmy whale named Isabela. Researchers first photographed the whale and collected her DNA in 1998 in the waters off the Galapagos Islands. Then, in 2006, another team photographed and collected samples from a similar looking whale off Chile (both photos above). Now, in a study published online before print in Marine Mammal Science, scientists compared those samples and photographs, and discovered that they both belonged to the same whale. That means Isabela (named after the lead author’s daughter to represent hope for future preservation efforts) migrated a minimum of 5200 km, the longest recorded latitudinal migration made by any Southern Hemisphere blue whale on record. The findings suggest Chile's and the Galapagos’ blue whale aggregations are connected, meaning those feeding in the Gulf of Corcovado off Chile may be breeding in the Tropical Eastern Pacific. Knowing where this species migrates—including its feeding and breeding grounds—can help conservationists and governments better establish marine protected areas, the team says. © 2015 American Association for the Advancement of Science

Keyword: Animal Migration
Link ID: 21213 - Posted: 07.25.2015

Jon Hamilton The face of Alzheimer's isn't always old. Sometimes it belongs to someone like Giedre Cohen, who is 37, yet struggles to remember her own name. Until about a year ago, Giedre was a "young, healthy, beautiful" woman just starting her life, says her husband, Tal Cohen, a real estate developer in Los Angeles. Now, he says, "her mind is slowly wasting away." People like Giedre have a rare gene mutation that causes symptoms of Alzheimer's to appear before they turn 60. Until recently, people who inherited this gene had no hope of avoiding dementia and an early death. Now there is a glimmer of hope, thanks to a project called DIAN TU that is allowing them to take part in a study of experimental Alzheimer's drugs. The project also could have a huge payoff for society, says Dr. Randall Bateman, a professor of neurology at Washington University in St. Louis. "It's highly likely," he says, that the first drug able to prevent or delay Alzheimer's will emerge from studies of people genetically destined to get the disease. Giedre Cohen enrolled in the DIAN TU study in 2013, when she still had no symptoms of Alzheimer's, her husband says. Their story began more than a decade earlier. In 2002, Tal Cohen was on a trip to Miami to attend a wedding. He met Giedre, who was born in Lithuania, and the two fell in love. © 2015 NPR

Keyword: Alzheimers
Link ID: 21211 - Posted: 07.23.2015