By Carrie Arnold Mike (not his real name) had always been an unusual child. Even as a toddler, he had ­difficulties relating to others and making friends, and he seemed strikingly ­suspicious of other people. After he entered high school, Mike became increasingly angry, paranoid and detached. He worried that people were searching his room and his locker when he was not around. His grades plum­meted as he turned ­inward during class, sketch­ing outlandish scenes in his note­books and muttering to himself rather than listening to the instructor. Paranoia and difficulties connecting with others are signs of psychosis, a mental illness in which people lose touch with reality. Psychotic individuals usually have problems forming rational, coherent thoughts. They also may hear voices or hallucinate while believing that what they perceive is real. Often such delusions result in bizarre behavior and, in severe cases, an inability to ­manage every­day life. But a psychiatrist deemed Mike’s symptoms too mild to qualify him as psychotic. Mike obviously needed some kind of professional intervention, so he bounced among psychiatrists who could not figure out how to help him. Cases such as Mike’s have prompted some practitioners to propose the inclusion of a new psychosis risk diagnosis to the forthcoming fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM), the “bible” of mental health diagnoses. To receive this diagnosis, a patient would first need to report, for example, having delusions or hallucinations about once a week (as opposed to most of the time for at least one month for clinical psychosis). In addition, either the patient or a loved one must be significantly distressed by those symptoms. The idea of including such a diagnosis in the DSM is highly controversial, but supporters argue that patients such as Mike not only need immediate help, they are at increased risk for developing full-blown psychosis, an outcome doctors might be able to prevent with early intervention. © 2011 Scientific American,

Keyword: Schizophrenia; Stress
Link ID: 15912 - Posted: 10.15.2011

by Chelsea Whyte Meat lovers, rejoice. The long-held notion that protein-rich diets are more filling appears to be true, which means that hitting the right balance between protein, carbohydrates and fat can curb overeating. Researchers from the University of Sydney, Australia, tested three diets on 22 male and female participants. All three diets were made up of the same meals and optional snacks, but modified to contain 10, 15 or 25 per cent protein. Each subject spent four days on each one. When on the 10 per cent protein diet, participants reported feeling hungrier in the 2 hours following breakfast than they were on both higher-protein diets. The menu with the least protein also caused the volunteers to snack more. From the first day to the last, participants ate a 12 per cent greater volume of food overall on this diet. "When protein in the diet is diluted by extra fat and carbohydrate, even by a small amount – something that has happened over recent decades in westernised countries – we keep eating in an attempt to attain our target level of protein," says Stephen Simpson, co-author of the study. Proteins are made up of amino acids, and circulating free amino acids are known to be important in the control of appetite, says Simpson. "There are amino-acid receptors in many places within the body, including parts of the brain known to be involved in control of feeding and hunger." Exactly how these amino acids act on the brain to suppress appetite needs investigating further, he adds. © Copyright Reed Business Information Ltd.

Keyword: Obesity
Link ID: 15911 - Posted: 10.13.2011

Melissae Fellet, reporter A paralysed man has high-fived his girlfriend using a robotic arm controlled only by his thoughts (see video above). Tim Hemmes, who was paralysed in a motorcycle accident seven years ago, is the first participant in a clinical trial testing a brain implant that directs movement of an external device. Neurosurgeons at the University of Pittsburgh School of Medicine in Pennsylvania implanted a grid of electrodes, about the size of a large postage stamp, on top of Hemmes's brain over an area of neurons that fire when he imagines moving his right arm. They threaded wires from the implant underneath the skin of his neck and pulled the ends out of his body near his chest. The team then connected the implant to a computer that converts specific brainwaves into particular actions. As shown in this video, Hemmes first practices controlling a dot on a TV screen with his mind. The dot moves right when he imagines bending his elbow. Thinking about wiggling his thumb makes the dot slide left. With practice, Hemmes learned to move the cursor just by visualizing the motion, rather than concentrating on specific arm movements, says neurosurgeon Elizabeth Tyler-Kabara of the University of Pittsburgh in Pennsylvania, who implanted the electrodes. © Copyright Reed Business Information Ltd.

Keyword: Robotics
Link ID: 15910 - Posted: 10.13.2011

by Jessica Hamzelou HUMAN minds wander when they have nothing else to do. This is when people start to introspect, using a specific network of brain structures. The same network has now been identified in monkeys and rats, suggesting that "zoning out" might serve a key function in our survival. The findings raise questions over whether lower animals might also be capable of something akin to introspection. The default mode network (DMN) is one of about 10 networks of brain regions that are active when a person is at rest. What makes the DMN interesting is that it becomes active when a person is asked to let their mind wander, but the network's activity drops away completely as soon as that person is given an external task. This suggests that, in humans at least, the DMN is involved in self-reflection and introspective thought processing. Building on recent evidence that anaesthetised monkeys might have a similar network, Wim Vanduffel and his colleagues at the Catholic University of Leuven (KUL) in Belgium collected a host of data from 15 studies which imaged the brain activity of 10 awake monkeys. By looking at the baseline brain activity measured in each project, the group was able to spot a network of brain structures that were active when the monkeys were not engaged in a task. This network looked strikingly similar to the human DMN (Journal of Neuroscience, DOI: 10.1523/jneurosci.2318-11.2011). © Copyright Reed Business Information Ltd.

Keyword: Attention
Link ID: 15909 - Posted: 10.13.2011

By BENEDICT CAREY Techniques being used to treat psychological lapses from traumatic brain injuries, the signature wounds suffered by troops in Iraq and Afghanistan, appear to be helpful, but lack rigorous scientific support, a government-appointed panel reported Tuesday after completing the most comprehensive analysis of the evidence to date. The report, completed by the Institute of Medicine at the request of the Defense Department, concluded that some specific methods — the use of special daily diaries, for instance, to improve memory — were backed by more evidence than others. But it concluded that the evidence base over all was too thin to support any guidelines for which therapies to provide to whom. Since 2009, the Pentagon has provided more than 71,000 hours of so-called cognitive rehabilitation, and its insurer, Tricare, has covered an additional 54,000 hours in private clinics for active duty, National Guard and retired service members, according to Cynthia O. Smith, a Department of Defense spokeswoman. Such rehabilitation methods have come under intense scrutiny from family members of veterans who suffered traumatic brain injuries, including those caused by nonpenetrating blasts, as well as wounds from bombs, bullets or blows to the head. Some 20 percent of service members wounded in Iraq and Afghanistan have suffered blows to the face, neck or head, and the number of brain injuries has nearly tripled in the past decade, to more than 30,000 from 11,000. © 2011 The New York Times Company

Keyword: Brain Injury/Concussion
Link ID: 15908 - Posted: 10.13.2011

A University of Northern B.C. professor who is studying the impact of the clinician-patient relationship on how health professionals rate pain suggests it decreases if the clinician doesn't like the patient. Pain sufferers often take issue with their treatment, which is why the research is so important, said psychology professor and pain expert Ken Prkachin. "A specific complaint being 'Nobody believes me, no one is taking me seriously,"' Prkachin described in an interview. "You really get that sense when you talk to patients, maybe people are being downgraded because they're also disliked." It means people with invisible pain — such as bad backs, as opposed to broken legs — may not get adequate treatment for the problem if the doctor disregards their feelings, he said. "A good case can be made … that is going to demoralize patients and contribute to very testy patient-professional relationships," Prkachin said. Study participants consistently rated the pain of patients associated with the negative traits, such as egotism and hostility, lower than the likeable patients. "What we're trying to do is understand what's going on there and how to change that." © CBC 2011

Keyword: Pain & Touch
Link ID: 15907 - Posted: 10.13.2011

By Piercarlo Valdesolo Recent reports of a mountain lion or cougar stalking the campus of the University of Iowa prompted campus jokesters to tweet their surprise that Michelle Bachman​ was in town. A cougar, colloquially, is an attractive older woman who seeks out trysts with younger men, and to some, it seems that Bachmann fits the bill. This emphasis on appearance is nothing new for high-profile women who are anything but homely, and feminist scholars are quick to point out its potential detrimental effects on perceptions of female competence. Of course, we don’t need to consider reactions to political candidates to understand this idea. There is a well-known tension between seeing someone as, and appreciating them for, a body as opposed to a mind. At least, that’s what parents tell their daughters when their school clothes veer too far towards the revealing. Science has backed parents up on this. A recent study found that showing men pictures of sexualized women evokes less activity in areas of the brain responsible for mental state attribution—that is, the area of the brain that becomes active when we think we are looking at an entity capable of thought and planned action. Other studies have found similar results. When men see body shots of women as compared with face shots, they judge women to be less intelligent, likeable, ambitious and competent. A new study by Kurt Gray and colleagues in the Journal of Personality and Social Psychology, however, suggests that this kind of objectification might not cause perceivers to see women as mindless bodies but instead cause a transformation in the kind of minds that they perceive. © 2011 Scientific American

Keyword: Sexual Behavior; Attention
Link ID: 15906 - Posted: 10.13.2011

By Rachael Rettner How fast a baby's brain grows, rather than how large it is, predicts the child's mental abilities later in life, a new study of preterm infants suggests. The faster the brain's cerebral cortex grew during the first months of life, the higher the children scored at age 6 on intelligence tests designed to measure their abilities to think, speak, plan and pay attention, the researchers found. The cerebral cortex is an outer layer of the brain that is critical for language, memory, attention and thought. The study found no relationship between the size of a baby's brain and the child's later test scores. While it's not clear whether the results would also apply to babies born full-term, researchers said the findings are helping them understand what might go wrong in the brains of preterm babies that causes many of those infants to experience cognitive problems later in life. "It points us to the fact that the period before normal birth is a critical time for brain growth," said study researcher David Edwards, a professor of neonatal medicine at Imperial College in London. Anything that disrupts this growth, including preterm birth or certain illnesses, may reduces cognitive abilities, Edwards said. © 2011 msnbc.com

Keyword: Development of the Brain; Intelligence
Link ID: 15905 - Posted: 10.13.2011

by Virginia Morell It's a scene that occurs daily among nesting colonies of Nazca boobies: A young adult bird struts over to a neighbor's chick and begins biting and pecking it, sometimes causing injuries that lead to the nestling's death. But if the chick survives, it's likely to become just like its tormentor, attacking other nestlings when it reaches maturity and perpetuating this "cycle of violence," researchers report. It's one of the first times that the cycle, which is normally used to explain child abuse in humans, has been discovered in a population of wild animals. The study appears in the October issue of The Auk. It's well known that children who suffer attacks by adults often grow up to abuse their own kids. But it's been difficult to study this cycle outside of humans or captive species, such as rhesus monkeys, that may exhibit some similar behaviors—because it is apparently rare, or at least seldom witnessed. On Española Island in the Galápagos, however, adult Nazca boobies attack chicks at an alarming rate, and the researchers say the birds' behavior offers a somewhat parallel model to that of humans. The birds are indifferent to human observers, so it's easy to spot and record the entire sequence of events, the researchers say. The sea birds' chick abuse is "one of the first things you notice; it's that obvious and disturbing," says David Anderson, an evolutionary ecologist at Wake Forest University in Winston-Salem, North Carolina, and one of the study's co-authors, who has been observing the boobies since 1984. The behavior is also surprising. "You don't expect to see animals wasting time, bothering with a neighbor's chick, when it could be doing something that benefits its fitness, like finding a mate." © 2010 American Association for the Advancement of Science

Keyword: Sexual Behavior; Aggression
Link ID: 15904 - Posted: 10.13.2011

By GRETCHEN REYNOLDS Scientific discoveries can be serendipitous, and so it was when Jay L. Alberts, then a Parkinson’s disease researcher at Emory University in Atlanta, mounted a tandem bike with Cathy Frazier, a Parkinson’s patient. The two were riding the 2003 RAGBRAI bicycle tour across Iowa, hoping to raise awareness of the neurodegenerative disease and “show people with Parkinson’s that you don’t have to sit back and let the disease take over your life,” Dr. Alberts says. But something unexpected happened after the first day’s riding. One of Ms. Frazier’s symptoms was myographia, a condition in which her handwriting, legible at first, would quickly become smaller, more spidery and unreadable as she continued to write. After a day of pedaling, though, she signed a birthday card with no difficulty, her signature “beautifully written,” Dr. Alberts says. She also told him that she felt as if she didn’t have Parkinson’s. Impressed, Dr. Alberts, who now holds an endowed research chair at the Cleveland Clinic in Ohio, embarked on a series of experiments in which he had people with Parkinson’s disease ride tandem bicycles. The preliminary results are raising fascinating questions not only about whether exercise can help to combat the disease but also — and of broader import — whether intense, essentially forced workouts affect brains differently than gentler activity, even in those of us who are healthy. Scientists have known for some time that, in lab animals, forced and voluntary exercise can lead to different outcomes. Generally, mice and rats enjoy running, so if you put a running wheel in a rodent’s cage, it will hop aboard and run. © 2011 The New York Times Company

Keyword: Parkinsons
Link ID: 15903 - Posted: 10.13.2011

By PERRI KLASS, M.D. Once, experts feared that young children exposed to more than one language would suffer “language confusion,” which might delay their speech development. Today, parents often are urged to capitalize on that early knack for acquiring language. Upscale schools market themselves with promises of deep immersion in Spanish — or Mandarin — for everyone, starting in kindergarten or even before. Yet while many parents recognize the utility of a second language, families bringing up children in non-English-speaking households, or trying to juggle two languages at home, are often desperate for information. And while the study of bilingual development has refuted those early fears about confusion and delay, there aren’t many research-based guidelines about the very early years and the best strategies for producing a happily bilingual child. But there is more and more research to draw on, reaching back to infancy and even to the womb. As the relatively new science of bilingualism pushes back to the origins of speech and language, scientists are teasing out the earliest differences between brains exposed to one language and brains exposed to two. Researchers have found ways to analyze infant behavior — where babies turn their gazes, how long they pay attention — to help figure out infant perceptions of sounds and words and languages, of what is familiar and what is unfamiliar to them. Now, analyzing the neurologic activity of babies’ brains as they hear language, and then comparing those early responses with the words that those children learn as they get older, is helping explain not just how the early brain listens to language, but how listening shapes the early brain. © 2011 The New York Times Company

Keyword: Language; Development of the Brain
Link ID: 15902 - Posted: 10.11.2011

By NICHOLAS BAKALAR The stress of living in a neonatal intensive care unit results in decreased brain size and abnormal neurological findings for very preterm babies, a small study suggests, and the more the stress, the greater the effect. Scientists at Washington University in St. Louis studied 44 infants born before 30 weeks of gestation. The researchers recorded the number of stressors the babies underwent, using a list of 36 procedures of varying invasiveness, from diaper changes to the insertion of intravenous lines. When the babies reached term-equivalent age, 36 to 44 weeks, they underwent M.R.I.’s and behavioral tests. The study was published online last week in The Annals of Neurology. After controlling for immaturity at birth and severity of illness, a higher score on the stress scale was associated with reduced brain size and poorer results on the examinations. There was no relation between number of stressors and brain injury. “We have to move away from a focus on just pain medications and acute medical interventions toward a more developmental approach,” said the study’s senior author, Dr. Terrie Inder, a professor of pediatrics. These babies, she added, “need the opportunity to rest, recover, be nurtured and be able to grow.” © 2011 The New York Times Company

Keyword: Stress; Development of the Brain
Link ID: 15901 - Posted: 10.11.2011

By RITCHIE S. KING A group of Japanese neuroscientists is trying to peer into the mind — literally. They have devised a way to turn the brain’s opaque gray matter into a glassy, see-through substance. The group, based at the government-financed Riken Brain Science Institute in Wako, Japan, has created an inexpensive chemical cocktail that transforms dead biological tissue from a colored mass into what looks like translucent jelly. Soaking brain tissue in the solution makes it easier for neuroscientists to see what’s inside, a step they hope will uncover the physical basis of personality traits, memories and even consciousness. “I’m very excited about the potential,” said Dr. Atsushi Miyawaki, a researcher on the team, which published its discovery in the journal Nature Neuroscience. The chemical solution — patented under the name Scale, a phonetic approximation of the Japanese word for “transparent” — could help neuroscientists map the brain’s underlying architecture, though that goal is still a distant one. At the moment, researchers are working to build such a map, called a “connectome,” of mouse brains, which are far less complex than human ones. Ultimately, this mapping could be conducted on brains of different ages, Dr. Miyawaki said, providing a glimpse into how the organ develops and even how genetic differences might affect that development. © 2011 The New York Times Company

Keyword: Brain imaging
Link ID: 15900 - Posted: 10.11.2011

by Linda Geddes MONKSEATON High School in Tyneside, UK, has seen some amazing improvements in the past year. Absenteeism is down, punctuality is up and exam results have gone through the roof. Head teacher Paul Kelley cannot attribute these successes to better teaching or stricter discipline. Instead, he simply started opening the school at 10 am instead of 9 am. The change was designed to synchronise the school day with pupils' body clocks. Teenagers are notoriously owlish, preferring to stay up into the small hours and sleep in till lunchtime. This isn't entirely their own fault: natural delays in secretion of the sleep hormone melatonin causes their body clocks to be shifted several hours backwards (New Scientist, 2 September 2006, p 40). By aligning the school day with these biological rhythms, Monkseaton school avoids teaching teenagers when their brains are still half asleep. In the modern world our lives are largely dictated by time. But even in the absence of clocks, schedules and calendars, our bodies still march to the beat of internal timekeepers called circadian rhythms. Over each 24-hour period we experience cycles of physical and mental changes that are thought to prepare our brains and bodies for the tasks we're likely to encounter at certain times of the day. The most obvious is the sleep-wake cycle, but there are many others. Circadian rhythms affect everything from how we perform on physical and mental tasks to when drugs are more likely to be effective. "We're not the same organism at midday and midnight," says Russell Foster, who researches circadian rhythms at the University of Oxford. © Copyright Reed Business Information Ltd.

Keyword: Attention
Link ID: 15899 - Posted: 10.11.2011

by Linda Geddes The life-saving treatment of therapeutic hypothermia is calling into question the guidelines doctors use to determine brain death IT'S a nightmarish scenario: a 55-year-old man, pronounced dead after a cardiac arrest, is minutes away from organ donation when he begins to show signs of life. "On being moved to the operating room table, the anaesthetist noticed that he was coughing," says neurologist Adam Webb of Emory University School of Medicine in Atlanta, Georgia, who initially pronounced the man brain dead. It transpired that the man had also regained corneal reflexes and was breathing - both signs of a functioning brainstem. Although the man later died, his case has reignited a debate about whether clearer guidelines are needed to determine brain death (Critical Care Medicine, DOI: 10.1097/CCM.0b013e3182186687). At issue is a treatment called therapeutic hypothermia, which Webb's patient had. It involves cooling the body to about 33 °C to minimise damage to tissues and brain cells caused by oxygen deprivation after a cardiac arrest. Since the publication of two landmark papers in 2002 in The New England Journal of Medicine, increasing numbers of hospitals are using therapeutic hypothermia. It saves lives, but the technique muddies the waters when it comes to determining brain death. It is also making it harder to predict who is likely to recover from a coma. © Copyright Reed Business Information Ltd.

Keyword: Stroke
Link ID: 15898 - Posted: 10.11.2011

By Linda Searing, THE QUESTION:Does Vitamin B12, known for its aid in making red blood cells and DNA, play a role in memory and cognition skills in older people? THIS STUDY: Analyzed data on 112 men and women 65 and older (average age, 79) who were given a battery of 17 tests of their memory and other cognitive skills; had blood drawn and were tested for five markers that reflect the presence of Vitamin B12; and were given an MRI scan to assess their brain volume, or size. Those whose blood indicated a Vitamin B12 deficiency, based on high levels of four of the five markers, also had lower scores on the memory and cognitive tests and smaller brain volumes. WHO MAY BE AFFECTED? Older people, who sometimes become deficient in Vitamin B12 because their stomachs can no longer absorb the nutrient as it occurs naturally in foods. To counter this, health experts suggest that they eat fortified foods (such as cereals) or take a dietary supplement because the stomach generally can still absorb the vitamin in those forms. Most people younger than 50 get plenty of B12 from their diets. It’s present in meat, fish, poultry, eggs and dairy products; beef liver and clams are considered the best sources of Vitamin B12. CAVEATS: The study involved a fairly small number of people. It did not test whether increasing Vitamin B12 levels would improve people’s memory and cognitive ability. FIND THIS STUDY: Sept. 27 issue of Neurology (www.neurology.org). © 1996-2011 The Washington Post

Keyword: Learning & Memory; Alzheimers
Link ID: 15897 - Posted: 10.11.2011

By James Gallagher Health reporter, BBC News One reason optimists retain a positive outlook even in the face of evidence to the contrary has been discovered, say researchers. A study, published in Nature Neuroscience, suggests the brain is very good at processing good news about the future. However, in some people, anything negative is practically ignored - with them retaining a positive world view. The authors said optimism did have important health benefits. Scientists at University College London said about 80% of people were optimists, even if they would not label themselves as such. They rated 14 people for their level of optimism and tested them in a brain scanner. Each was asked how likely 80 different "bad events" - including a divorce or having cancer - were to happen. They were then told how likely this was in reality. At the end of the session, the participants were asked to rate the probabilities again. There was a marked difference in the updated scores of optimists depending on whether the reality was good or bad news. BBC © 2011

Keyword: Emotions
Link ID: 15896 - Posted: 10.10.2011

By Richard Ridderinkhof How much can the brain recover from years of excessive alcohol consumption? —Paul Howlen, London Evidence shows that heavy alcohol use modifies the structure and physiology of the brain, although the extent of recovery after years of abstinence is unclear. Recent neuroimaging studies have revealed that chronic alcoholism can damage the cerebellum, which plays an important role in regulating motor control, attention and language. It can also cause the prefrontal cortex to shrink and degrade, potentially impairing decision-making skills and social behavior. Studies have also found damage in the white matter of the brain, which connects these regions. The question remains, however, whether such extensive damage can be reversed after abstaining from alcohol. Researchers have studied the effects of abstinence on the brains of alcohol-dependent individuals by comparing subjects recovering from years of alcohol abuse with those who do not drink or drink minimally. Scientists have also investigated changes in brain volume in initial versus sustained abstinence in one set of subjects. Several of these studies have shown that years of abstaining from booze can allow brain regions to return to their original volume and can repair neural connections across different regions. Much of this restoration occurs in the system most adversely affected by chronic alcoholism—the frontocerebellar circuitry, which regulates decision making, reasoning and problem solving. © 2011 Scientific American

Keyword: Drug Abuse; Brain imaging
Link ID: 15895 - Posted: 10.10.2011

By JANE ROSETT “WANT a piece of gum, Jane?” asked my friend Andrée. “What?” I asked her. “Gum!” I didn’t know what she was talking about. “It’s Trident.” It was delicious. That evening, I told my friend David about my day’s big discovery. “It’s called gum and you chew it and it’s fun and there’s this one kind that will let me blow bubbles!” “Yes, it’s called bubble gum, Jane,” he told me, patiently. Fifty-nine months ago, I was wearing my seat belt and my car was stopped when another vehicle hit me, causing my head to fracture the windshield. That damaged my right temporal lobe, one of my neurologists explained when he told me I had a traumatic brain injury. I lost my long-term memory, and have been a brain injury patient within Harvard Medical School’s teaching hospitals ever since. At 45, I was jolted into an entirely new existence. Memories that connected different parts of my life fragmented and vanished. It took 26 months before I was able to thread my way back unattended to the house I had lived in for 17 years. © 2011 The New York Times Company

Keyword: Brain Injury/Concussion; Learning & Memory
Link ID: 15894 - Posted: 10.10.2011

By ALEXANDRA HOROWITZ and AMMON SHEA SHAKESPEARE may have written “O, how bitter a thing it is to look into happiness through another man’s eyes,” but he apparently never met many psychologists, a good number of whom have been attempting to do exactly this for some time. Psychology and its social-science cousin, behavioral economics, seem to have a lock on “happiness studies,” tackling vexing questions about our positive and negative moods and our feelings of satisfaction and well-being. Recently, we wondered what other approaches were being taken to this venerable subject. Here are a few recent findings from less expected sources — bee and sheep scientists, linguists and artificial intelligence experts. In describing nonhuman animal populations, scientists are disinclined to use the word “happiness” (or especially “unhappiness”) to describe their charges. But there have been a few papers testing a related disposition: an animal’s “pessimism” or “optimism.” Consider “Release from Restraint Generates a Positive Judgment Bias in Sheep” (Applied Animal Behavior Science, 2010). In this study, 20 young merino ewes were trained to distinguish between two buckets, one of which led to food and another to the appearance of a dog — a highly unpleasant sight for a young ewe. Half of the animals were then bound at their legs and isolated from the other animals for six hours, three days in a row. On release from their imprisonment, this experimental group was shown a new, “ambiguous” bucket, which did not clearly lead to either food or dog. The previously imprisoned animals, despite their elevated stress levels, were much more likely to approach the ambiguous bucket than were a control group of ewes. Against all odds, they were, in a word, optimistic that the bucket might lead to something good. © 2011 The New York Times Company

Keyword: Emotions; Evolution
Link ID: 15893 - Posted: 10.10.2011