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SAN DIEGO, CALIFORNIA—The nine-banded armadillo (Dasypus novemcinctus) has many hidden skills—it can sniff out insects buried 20 cm underground, for example, and jump more than a meter into the air when startled. Seeing, however, is not one of its natural talents. Because its eyes lack light-detecting cells called cones, it has fuzzy, colorless vision. The light-receptive cells that an armadillo does have, called rods, are so sensitive that daylight renders the nocturnal animals practically blind. But the deficit may have a silver lining for humans. To study diseases that cause blindness in people, scientists typically genetically “knock out” cone-related genes in animals like mice. Such studies are limited, because they examine only one gene at a time, when a number of different genes contribute to cone dysfunction, researchers say. By comparing the armadillo gene to other closely related mammals, a team of scientists has now identified several cone-related genes in the armadillo genome that became nonfunctional millions of years ago, they report today at the Society for Neuroscience conference in San Diego, California. This makes the animals "excellent candidates" for gene therapy experiments that could restore color vision and point the way to potential human treatments, they say. © 2013 American Association for the Advancement of Science.

Keyword: Vision; Genes & Behavior
Link ID: 18923 - Posted: 11.14.2013

Helen Shen Long used to treat movement disorders, deep-brain stimulation (DBS) is rapidly emerging as an experimental therapy for neuropsychiatric conditions including depression, Tourette’s syndrome, obsessive–compulsive disorder and even Alzheimer’s disease. But despite some encouraging results in patients, it remains largely unknown how the electrical pulses delivered by implants deep within the brain affect neural circuits and change behaviour. Now there is a prototype DBS device that could provide some answers, researchers reported on 10 November at the Society for Neuroscience’s annual meeting in San Diego, California. Called Harmoni, the device is the first DBS implant to monitor electrical and chemical responses in the brain while delivering electrical stimulation. “That’s new data that we haven’t really had access to in humans before,” says Cameron McIntyre, a biomedical engineer at Case Western Reserve University in Cleveland, Ohio, who is not involved in the work. Researchers hope that the device will identify the electrical and chemical signals in the brain that correlate in real time with the presence and severity of symptoms, including the tremors experienced by people with Parkinson’s disease. This information could help to uncover where and how DBS exerts its therapeutic effects on the brain, and why it sometimes fails, says Kendall Lee, a neurosurgeon at the Mayo Clinic in Rochester, Minnesota, who is leading the project. The results come at a time of great excitement in the DBS field. Last month, the US government's Defense Advanced Research Projects Agency (DARPA) announced a 5-year, US$70-million initiative to support development of the next generation of therapeutic brain-stimulating technologies. © 2013 Nature Publishing Group,

Keyword: Parkinsons
Link ID: 18922 - Posted: 11.13.2013

Heavy smokers who regularly puffed more than a packet of cigarettes a day cut down or quit for six months after their brains were stimulated with magnets, researchers say. The apparent success of the simple procedure has led the scientists to organise a large-scale trial which will launch early next year at 15 medical centres worldwide. Smokers in the pilot study had already tried anti-smoking drugs, nicotine gum and patches or psychotherapy to no avail, raising hopes that magnetic stimulation might offer an effective alternative for those who want to give up but have so far failed. Nearly half of the smokers in one group, who received high-frequency magnetic pulses, quit after a three-week course of stimulation, with more than a third still abstaining six months on. "This is a new approach to the problem," said neuroscientist Abraham Zangen of Ben-Gurion University in Israel. "These are heavy smokers who could not stop smoking before." More trials will be needed to prove the value of the procedure, which scientists say should only be offered within a psychotherapy-based programme designed specifically for smokers. For the pilot study, Zangen recruited 115 people aged 21-70 who smoked at least 20 a day. Only those who had tried to give up before using at least two methods were allowed to take part in the programme. The smokers were divided into three groups. The first had 15 minutes of high-frequency magnetic stimulation every weekday for two weeks, followed by three sessions in the third week. © 2013 Guardian News and Media Limited

Keyword: Drug Abuse
Link ID: 18921 - Posted: 11.13.2013

Sedentary adults may improve their memory as soon as six weeks after taking up aerobic exercise, a small brain imaging study suggests. Cardiovascular fitness and cognitive performance such as attention seem to improve after six months or more of aerobic exercise in previous aging studies. Now researchers in Texas have found signs of increased regional blood flow in the brain of 37 sedentary adults with an average age of 64 who were randomized to physical training or a control group who had the training after a waiting period. They found a higher resting cerebral blood flow in the brain's anterior cingulate region in the physical training group compared with controls. The anterior cingulate region is associated with better memory functions. The size of this brain region was also larger in another study of "successful cognitive agers" over the age of 80 compared to middle-aged or elderly controls. "A relatively rapid health benefit across brain, memory and fitness in sedentary adults soon after starting to exercise, some gains starting as early as six weeks, could motivate adults to start exercising regularly," the study's lead author, Sandra Bond Champman of the Center for BrainHealth in Dallas and her co-authors concluded in Monday's issue of the journal Frontiers in Aging Neuroscience. "The current findings shed new light on ways exercise promotes cognitive/brain health in aging." The participants all had a physical exam and screening for dementia, early cognitive impairment, depression and IQ before the study began. A noninvasive type of MRI was used to measure brain blood flow before, half way through the 6-week training sessions and at 12 weeks. © CBC 2013

Keyword: Learning & Memory
Link ID: 18920 - Posted: 11.13.2013

By Julianne Chiaet Kate wanted to die. She remembers the moment the psychiatrist said “the antidepressant isn’t going to work right away. Can you promise to be here next week and not kill yourself?” “I told her no,” Kate says. “I couldn’t promise my doctor I’d make it a week. That’s how bad my life had to be before I got help. When you’re struggling to stay alive every single day, and then your doctor tells you it’s going to take two to six weeks before the medications they give you are going to work, it’s devastating.” To make matters worse, after those weeks, the drug didn’t work. Kate went through five different anti-depressants over the course of six months before confirming that none of them worked. The debilitating disorder kept her out of school for extended periods of time. The National Center for Health Statistics estimates more than 1 in 10 Americans over the age of 12 took antidepressants between 2005 and 2008, the last time period for which the data are available. The rate of antidepressant use increased 400 percent from 1998 to 2008. Traditional antidepressants go after serotonin neurotransmitters, which sit in the membrane of the brain. Some antidepressants also target norepinephrine and dopamine. The drug keeps the transmitters from performing their normal function of transporting serotonin from the outside to the inside of the brain cells. People with depression have a normal amount of serotonin inside of their brain cells, however they have an insufficient amount on the outside of their cells. Thus by inhibiting the transmitter, the drug blocks the transportation of serotonin being taken into the cell, thus building up the serotonin outside of the cell. © 2013 Scientific American

Keyword: Depression
Link ID: 18919 - Posted: 11.13.2013

by Jennifer Viegas Music skills evolved at least 30 million years ago in the common ancestor of humans and monkeys, according to a new study that could help explain why chimpanzees drum on tree roots and monkey calls sound like singing. The study, published in the latest issue of Biology Letters, also suggests an answer to this chicken-and-egg question: Which came first, language or music? The answer appears to be music. "Musical behaviors would constitute a first step towards phonological patterning, and therefore language," lead author Andrea Ravignani told Discovery News. For the study, Ravignani, a doctoral candidate at the University of Vienna's Department of Cognitive Biology, and his colleagues focused on an ability known as "dependency detection." This has to do with recognizing relationships between syllables, words and musical notes. For example, once we hear a certain pattern like Do-Re-Mi, we listen for it again. Hearing something like Do-Re-Fa sounds wrong because it violates the expected pattern. Normally monkeys don't respond the same way, but this research grabbed their attention since it used sounds within their frequency ranges. In the study, squirrel monkeys sat in a sound booth and listened to a set of three novel patterns. (The researchers fed the monkeys insects between playbacks, so the monkeys quickly got to like this activity.) Whenever a pattern changed, similar to our hearing Do-Re-Fa, the monkeys stared longer, as if to say, "Huh?" © 2013 Discovery Communications, LLC.

Keyword: Hearing; Language
Link ID: 18918 - Posted: 11.13.2013

SAN DIEGO, CALIFORNIA—Why do teens—especially adolescent males—commit crimes more frequently than adults? One explanation may be that as a group, teenagers react more impulsively to threatening situations than do children or adults, likely because their brains have to work harder to reign in their behavior, a research team reported here yesterday at the Society for Neuroscience meeting. Whether it's driving too fast on a slick road or experimenting with drugs, teenagers have a reputation for courting danger that is often attributed to immaturity or poor decision-making. If immaturity or lack of judgment were the only problem, however, one would expect that children, whose brains are at an even earlier stage of development, would have an equal or greater penchant for risk-taking, says Kristina Caudle, a neuroscientist at the Weill Cornell Medical College in New York City who led the study. But younger children tend to be more cautious than teenagers, suggesting that there is something unique about adolescent brain development that lures them to danger, she says. It's hard to generalize about teenage impulsivity, because some adolescents clearly have more self-control than many adults, says principal investigator B. J. Casey, a neuroscientist. Still, a growing body of evidence suggests that, in general, teens specifically struggle to keep their cool in social situations, she says. Because many crimes committed during adolescence involve emotionally fraught social situations, such as conflict, Caudle and colleagues decided to test whether teens perform badly on a common impulsivity task when faced with social cues of threat. They recruited 83 people, ranging in age from 6 to 29, to perform a simple "Go/No-Go" task, in which they watched a series of faces making neutral or threatening facial expressions flicker past on a computer screen. Each time the participants saw a neutral face, they were instructed to hit a button. They were also told to hold back from pressing the button when they saw a threatening face. As the participants performed the task, the researchers monitored their brain activity with functional magnetic resonance imaging. © 2013 American Association for the Advancement of Science.

Keyword: Development of the Brain; Attention
Link ID: 18917 - Posted: 11.12.2013

Babies born to women who exercised during pregnancy have enhanced brain development compared with babies born to moms who didn’t exercise while they were pregnant, a new Canadian study suggests. The babies of 10 women who did as little as 20 minutes of moderate exercise three times a week during pregnancy showed more advanced brain activity when they were tested at eight to 12 days old than the babies of eight women who did not exercise during pregnancy, reported University of Montreal researcher David Ellemberg and his colleagues at the Neuroscience 2013 conference in San Diego on Sunday. “We are optimistic that this will encourage women to change their health habits, given that the simple act of exercising during pregnancy could make a difference for their child's future,” Ellemberg said in a statement. The women in the study were randomly assigned to an exercise group or a sedentary group at the beginning of their second trimester. Those in the exercise group had to spend at least 20 minutes three times a week doing exercise intense enough to lead to at least a slight shortness of breath. After their babies were born, the researchers tested them by placing a cap of electrodes on the babies' heads and then playing novel sounds while they slept. They measured the electrical response of the babies' brains to see how well they could distinguish between different sounds. The researchers found that the babies in the exercise group produced signals associated with more mature brains. The researchers said they plan to test the children’s cognitive, motor and language development at age one to see if there are lasting effects. © CBC 2013

Keyword: Development of the Brain
Link ID: 18916 - Posted: 11.12.2013

Brian Owens The hordes of microbes that inhabit every nook and cranny of every animal are not just passive hitchhikers: they actively shape their hosts’ well-being and even behaviour. Now, researchers have found evidence that bacteria living in the scent glands of hyenas help to produce the smells that the animals use to identify group members and tell when females are ready to mate. Kevin Theis, a microbial ecologist at Michigan State University in East Lansing, had been studying hyena scent communication for several years when, after he gave a talk on the subject, someone asked him what part the bacteria might play. “I just said, ‘I don’t know’,” he says. He started investigating. He found that for 40 years, scientists had wondered whether smelly bacteria were involved in animals' chemical communication. But experiments to determine which bacteria were present had been inconclusive, because the microbes had to be grown in culture, which is not possible with all bacteria. However, next-generation genetic sequencing would enable Theis to identify the microbes in a sample without having to grow them in a dish. Using this technique, Theis and his colleagues last year published a study1 that identified more types of bacterium living in the hyenas’ scent glands than the 15 previous studies of mammal scent glands combined. In both spotted hyenas (Crocuta crocuta) and striped hyenas (Hyaena hyaena), most of the bacteria were of a kind that ferments nutrients exuded by the skin and produces odours. “The diversity of the bacteria is enough to potentially explain the origin of these signals,” says Theis. Now, they have found that the structure of the bacterial communities varied depending on the scent profiles of the sour, musky-smelling 'pastes' that the animals left on grass stalks to communicate with members of their clan. In addition, in the spotted hyenas, both the bacterial and scent profiles varied between males and females, and with the reproductive state of females — all attributes that hyenas are known to be able to infer from scent pastes. The work is published this week in Proceedings of the National Academy of Sciences. © 2013 Nature Publishing Group

Keyword: Chemical Senses (Smell & Taste); Sexual Behavior
Link ID: 18915 - Posted: 11.12.2013

By PAM BELLUCK It is probably no accident that the pivotal object in Martin Cruz Smith’s newest detective thriller, “Tatiana,” is a notebook nobody can read. Early on, Mr. Smith worried that his novel, being published Tuesday by Simon & Schuster, would be unreadable too — or wouldn’t be written at all. Author of the 1981 blockbuster “Gorky Park” and many acclaimed books since, Mr. Smith writes about people who uncover and keep secrets. But for 18 years, he has had a secret of his own. In 1995, he received a diagnosis of Parkinson’s disease. But he kept it hidden, not only from the public, but from his publisher and editors. He concealed it, although for years, tremors and stiffness have kept him from taking detailed notes and sketching people, places and objects for his research — and even as he became unable to type the words he needed to finish his 2010 best seller “Three Stations.” “I didn’t want to be judged by that,” Mr. Smith, 71, explained recently in his light-filled Victorian home north of San Francisco. “Either I’m a good writer or I’m not. ‘He’s our pre-eminent Parkinson’s writer.’ Who needs that?” In talking about his Parkinson’s odyssey, including a relatively new but promising treatment, Mr. Smith is opening a window on the still incurable disorder affecting four million people worldwide, a disease that is becoming increasingly prevalent as baby boomers age. His experience reflects a common desire to conceal often-stigmatizing symptoms, like shaking, slowness, and rigidity. (He mostly didn’t mind his Parkinsonian hallucinations: a black cat in his lap, whirlwinds spiraling from computer keys, a butler, a British military officer in full regalia. “Having hallucinations for a fiction writer is redundant,” he said.) Copyright 2013 The New York Times Company

Keyword: Parkinsons
Link ID: 18914 - Posted: 11.12.2013

By Michelle Roberts Health editor, BBC News online Depression can make us physically older by speeding up the ageing process in our cells, according to a study. Lab tests showed cells looked biologically older in people who were severely depressed or who had been in the past. These visible differences in a measure of cell ageing called telomere length couldn't be explained by other factors, such as whether a person smoked. The findings, in more than 2,000 people, appear in Molecular Psychiatry. Experts already know that people with major depression are at increased risk of age-related diseases such as cancer, diabetes, obesity and heart disease. This might be partly down to unhealthy lifestyle behaviours such as alcohol use and physical inactivity. But scientists suspect depression takes its own toll on our cells. To investigate, Josine Verhoeven from the VU University Medical Centre in the Netherlands, along with colleagues from the US, recruited 2,407 people to take part in the study. More than one third of the volunteers were currently depressed, a third had experienced major depression in the past and the rest had never been depressed. The volunteers were asked to give a blood sample for the researchers to analyse in the lab for signs of cellular ageing. The researchers were looking for changes in structures deep inside cells called telomeres. BBC © 2013

Keyword: Depression
Link ID: 18913 - Posted: 11.12.2013

By PAULA SPAN Jim Cooke blames his hearing loss on the constant roar of C-119 aircraft engines he experienced in the Air Force. He didn’t wear protective gear because, like most 20-year-olds, “you think you’re indestructible,” he said. By the time he was 45, he needed hearing aids for both ears. Still, he had a long career as a telephone company executive while he and his wife, Jean, raised two children in Broadview Heights, Ohio. Only after retirement, he told me in an interview, did he start having trouble communicating. Jean and Jim Cooke Jean and Jim Cooke Mr. Cooke had to relinquish a couple of part-time jobs he enjoyed because “I felt insecure about dealing with people on the phone,” he said. He withdrew from a church organization he led because he couldn’t grasp what members were saying at meetings. “He didn’t want to be in social situations,” Mrs. Cooke said. “It gave him a feeling of inadequacy, and anger at times.” Two years ago, when their grandchildren began saying that Granddad needed to replace his hearing aid batteries — although the batteries were fine — the Cookes went to the Cleveland Clinic, where an audiologist there, Dr. Sarah Sydlowski, told Jim that at 76, he might consider a cochlear implant. Perhaps the heart-tugging YouTube videos of deaf toddlers suddenly hearing sounds have led us to think of cochlear implants as primarily for children. Or perhaps, said Dr. Frank R. Lin, a Johns Hopkins University epidemiologist, we consider late-life hearing loss normal (which it is), “an unfortunate but inconsequential aspect of aging,” and don’t explore treatment beyond hearing aids. In any case, the idea of older adults having a complex electronic device surgically implanted has been slow to catch on, even though by far the greatest number of people with severe hearing loss are seniors. © 2013 The New York Times Company

Keyword: Hearing; Robotics
Link ID: 18912 - Posted: 11.12.2013

by Ashley Yeager The compound that gives mold its musty smell can cause changes in fruit flies’ brains that mimic those of patients with Parkinson’s disease. Scientists do not know the exact cause of Parkinson’s disease, but studies have shown that exposure to human-made chemicals may be a risk factor for developing the movement disorder. Now researchers have found that the chemical 1-octen-3-ol, which mold naturally emits, kills flies’ brain cells that transmit dopamine, a compound involved in controlling movement. The mold molecule also reduces dopamine levels in the flies’ brains. In experiments with human cells, the mold chemical also blocked the cells from taking in dopamine, researchers report November 11 in the Proceedings of the National Academy of Sciences. The results offer insight into cases of movement problems that doctors have associated with fungi exposure, the scientists say. © Society for Science & the Public 2000 - 2013

Keyword: Movement Disorders; Neurotoxins
Link ID: 18911 - Posted: 11.12.2013

SAN DIEGO, CALIFORNIA—How do we recognize emotions in the facial expressions of others? A small, almond-shaped structure called the amygdala, located deep within the brain (yellow in image above), plays a key role, but exactly what it responds to is unclear. To learn more, neuroscientists implanted electrodes into the amygdalae of seven epileptic patients who were about to undergo brain surgery for their condition. They recorded the activity of 200 single amygdala neurons and determined how they responded while the patients viewed photographs of happy and fearful faces. The team found a subset of cells that distinguish between what the patients thought to be happy and fearful faces, even when they perceived ambiguous facial expressions incorrectly. (The team carefully manipulated some of the photos of fearful faces, so that some of the subjects perceived them as being neutral.) The findings, presented here yesterday at the 43rd annual meeting of the Society for Neuroscience, suggest that amygdala neurons respond to the subjective judgement of emotions in facial expressions, rather than the visual characteristics of faces that convey emotions. The scientists also found that the cellular responses persisted long after each of the photographs disappeared, further suggesting that the amygdala cooperates with other brain regions to create awareness of the emotional content of faces. Thus, when it comes to recognizing the facial expressions of others, what we think we see seems to be more important than what we actually see. © 2013 American Association for the Advancement of Science.

Keyword: Vision; Emotions
Link ID: 18910 - Posted: 11.12.2013

Ian Sample, science correspondent in San Diego Criminal courts in the United States are facing a surge in the number of defendants arguing that their brains were to blame for their crimes and relying on questionable scans and other controversial, unproven neuroscience, a legal expert who has advised the president has warned. Nita Farahany, a professor of law who sits on Barack Obama's bioethics advisory panel, told a Society for Neuroscience meeting in San Diego that those on trial were mounting ever more sophisticated defences that drew on neurological evidence in an effort to show they were not fully responsible for murderous or other criminal actions. Lawyers typically drew on brain scans and neuropsychological tests to reduce defendants' sentences, but in a substantial number of cases the evidence was used to try to clear defendants of all culpability. "What is novel is the use by criminal defendants to say, essentially, that my brain made me do it," Farahany said following an analysis of more than 1,500 judicial opinions from 2005 to 2012. The rise of so-called neurolaw cases has caused serious concerns in the country where brain science first appeared in murder cases. The supreme court has begun a review of how such evidence can be used in criminal cases. But legal and scientific experts nevertheless foresee the trend spreading to other countries, including the UK, and Farahany said she was expanding her work abroad. The survey even found cases where defendants had used neuroscience to argue that their confessions should be struck out because they were not competent to provide them. "When people introduce this evidence for competency, it has actually been relatively successful," Farahany said. © 2013 Guardian News and Media Limited

Keyword: Brain imaging; Aggression
Link ID: 18909 - Posted: 11.11.2013

Jessica Wright A new test of mouse intelligence closely mimics the types of assays used with people and detects a subtle learning deficit reminiscent of one seen in teenagers with autism, according to findings presented Saturday at the2013 Society for Neuroscience annual meeting in San Diego. Another behavioral test, also presented Saturday, uncovers an unexpected social deficit in an autism mouse model. The test in the first study could be used to screen for drugs that improve cognitive deficits associated with autism, says Jill Silverman, a postdoctoral associate in Jacqueline Crawley’s lab at the University of California, Davis MIND Institute. Silverman presented the work at a poster session. To measure learning in mice, researchers typically place them in a water maze, or see if they learn to anticipate an electric shock. “But you don’t shock people or put them in a pool to swim,” notes Silverman. Silverman instead trained the mice in a human activity: using a touchscreen. In the most basic form of the test, the mice see two graphic images (such as a plane and a spider) and learn that they get “yummy” strawberry milkshake if they touch the spider, Silverman says. (She says she uses milkshakes because the mice work hard for them, even if they aren’t hungry.) BTBR mice, which have many autism-like features, learn to go for the spider just as readily as control mice do. So Silverman made things much more complicated. The complex test follows the logic of transitive properties. For example, if John is taller than Anne and Anne is taller than Jane, we are able to infer that John is taller than Jane. © Copyright 2013 Simons Foundation

Keyword: Autism; Learning & Memory
Link ID: 18908 - Posted: 11.11.2013

The long-term impact of roadside bombings on the brains of Canadian soldiers in Afghanistan is the focus of two research projects underway in Western Canada. "In recent years, encounters with improvised explosive devices or IEDs in Afghanistan have inflicted traumatic brain injury on a number of Canadian soldiers," said Dr. Robert Thirsk, a former Canadian astronaut who is now a vice-president with the Canadian Institute of Health Research. "The impact of these blasts may not be immediately apparent. Months after the event the soldiers can suffer from the neurological problems and the mental disorders like anxiety that we're reading about in the newspapers. These weapons may be improvised, but our response to them needs to be strategic." Dr. Yu Tian Wang of the Brain Research Center at the University of British Columbia is looking at the biological changes that occur in the brain at the cellular level following an injury by an explosive device. Wang is studying whether a drug can reduce the death and dysfunction of brain cells following injury. "We know that during traumatic brain injuries some synaptic connections become weakened and the information from one neuron to another is slowed down," Wang said. "Now we know the underlying reason is due to a particular memory surface protein being reduced." Wang said an injection of peptides could provide protection to brain cells before a blast and possibly help repair damage if given immediately after an explosion. © CBC 2013

Keyword: Brain Injury/Concussion
Link ID: 18907 - Posted: 11.11.2013

Sarah DeWeerdt Parts of the brain that process vision and control movements are poorly connected in children with autism, according to results presented Saturday at the 2013 Society for Neuroscience annual meeting in San Diego. In addition to the social deficits that are a core feature of autism, children with the disorder often have clumsy movements. Studies have also found that people with autism have trouble imitating others. The new study uncovers patterns of brain activity suggesting all three of these deficits may be related. The researchers used functional magnetic resonance imaging (fMRI) to measure resting-state activation — brain activity that occurs while individuals are resting quietly in the scanner — in 45 children with autism and 45 controls. Parts of the brain that tend to activate and deactivate together during this procedure are said to be functionally connected. The researchers zeroed in on two sets of brain structures involved in motor activity. One of them, the ventral motor component, includes parts of the cortex, the thalamus and lobule 6 of the cerebellum. They also focused on three areas of the brain involved in visual processing. The most interesting is a region at the back of the brain responsible for complex interpretation of visual information. © Copyright 2013 Simons Foundation

Keyword: Autism; Vision
Link ID: 18906 - Posted: 11.11.2013

By SENDHIL MULLAINATHAN Why is obesity soaring? The answer seems pretty clear. In 1955, a standard soda at McDonald’s was only seven ounces. Today, a medium is three times as large, and even a child’s-size version is 12 ounces. It’s a widely held view that obesity is a consequence of our behaviors, and that behavioral economics thus plays a central role in understanding it — with markets, preferences and choices taking center stage. As a behavioral economist, I subscribed to that view — until recently, when I began to question my thinking. For many health problems, of course, behavior plays some role but biology is often a major villain. “Biology” here is my catchall term for the myriad bodily mechanics that are only weakly connected to our choices. A few studies have led me to wonder whether the same is true with obesity. Have I been the proverbial owner of a (behavioral) hammer, looking for (behavioral) nails everywhere? Have I failed to appreciate the role of biology? A first warning sign comes from looking at other animals. Our pets have been getting fatter along with us. In 2012, some 58.3 percent of cats were, literally, fat cats. That is taken from a survey by the Association for Pet Obesity Prevention. (The very existence of this organization is telling.) Pet obesity, however, can easily be tied to human behavior: a culture that eats more probably feeds its animals more, too. And yet, a study by a group of biostatisticians in the Proceedings of the Royal Society challenges this interpretation. They collected data from animals raised in captivity: macaques, marmosets, chimpanzees, vervets, lab rats and mice. The data came from labs and centers and spanned several decades. These captive animals are also becoming fatter: weight gain for female lab mice, for example, came out to 11.8 percent a decade from 1982 to 2003. But this weight gain is harder to explain. Captive animals are fed carefully controlled diets, which the researchers argue have not changed for decades. Animal obesity cannot be explained through eating behavior alone. We must look to some other — biological — driver. © 2013 The New York Times Company

Keyword: Obesity
Link ID: 18905 - Posted: 11.10.2013

Anjan Chatterjee Before I realized what was happening, the patient reached down between my legs and grabbed my genitals. It was 1985, in the middle of the night during my medicine internship. I was working about 110 hours a week. Every third night I was on call and felt lucky if I got a couple of hours of sleep. That night, I was taking care of this patient for another intern. On my endless “to do” list was the task of placing an intravenous line. When I got to her room it was dark. I didn’t know what her medical condition was. I was focused on starting her IV and then moving on to my next task. I turned on the soft light over her hospital bed and gently woke her. She seemed calm. I loosened her restrained arm to look for a good vein. That was when she grabbed me. Even in my sleep-, food-, and sex-deprived state, I recognized that my charms were not the reason for her attention. She acted indiscriminately. She grabbed nurse’s breasts and students’ buttocks with the same enthusiasm. I had not yet started my neurology residency and did not know that she was suffering from a human version of Klüver-Bucy syndrome. The syndrome is named after Heinrich Klüver, a psychologist, and Paul Bucy, a neurosurgeon, who observed that rhesus monkeys changed profoundly when their anterior-medial temporal lobes were removed. They became placid. They were no longer fearful of objects they would normally avoid. They became “hyper-oral,” meaning they would put anything and everything in their mouth. They also became hypersexual. A similar syndrome occurs in humans. The patient I encountered that night had an infection affecting parts of her brain analogous to those parts in monkeys that Paul Bucy removed. All the cultural and neural machinery that puts a check on such behavior was dissolved by her infection. She displayed sexual desire, the deep-rooted instinct that ensures the survival of our species, in its most uninhibited form. © 2013 Salon Media Group, Inc.

Keyword: Sexual Behavior
Link ID: 18904 - Posted: 11.10.2013