Igor Stravinsky once characterized his music as being "best understood by children and animals." Though some people might not agree with it, Stravinsky's claim highlights an intriguing evolutionary question: Is our appreciation for music innate? And, if so, would that appreciation be shared by our evolutionary ancestors? A new study slated for publication in the journal Cognition reports that our ancestors may not, in fact, be audiophiles. Non-human primates appear to prefer silence to music, suggesting that musical appreciation may be uniquely human. "We're really in the first stages of looking into these things," said Josh McDermott, a perceptual scientist at MIT and coauthor of the study. "But everything we've done suggests fairly striking differences in the way that humans hear music and the way that animals do." McDermott and Harvard evolutionary psychologist Marc D. Hauser found in earlier studies that tamarin and marmoset monkeys have the ability to discriminate between different types of music to the point of noticing pieces written by different composers. © Copyright 2006 Seed Media Group, LLC.

Keyword: Hearing
Link ID: 9387 - Posted: 06.24.2010

By Jane Elliott When Owain Morgan needed to come up with a design to help people who had suffered a stroke, he turned to his own family for inspiration. His grandmother and uncle had both had strokes and talking to them he realised something as simple as a device to help them tear toilet and kitchen paper with one hand could make a big difference to their lives. "It didn't really occur to me before talking to them that this might be a problem for people - that something so simple could help," said 18-year-old Owain, an apprentice from South Wales. There are more than 450,000 people living in the UK who, as a result of a stroke, need to rely on others to help with simple everyday tasks like these. In a bid to raise awareness of the problem and do something to help those who have had a stroke, the UK defence and aerospace group, BAE Systems set their apprentices the challenge of designing devices to make lives easier. The teams had either to develop a mechanical aid to help people who had paralysis of a limb to do everyday activities, or design an electrical aid to help those with speech problems (dysphasia) communicate in everyday situations. (C)BBC

Keyword: Stroke
Link ID: 9386 - Posted: 09.25.2006

By Shankar Vedantam Whenever my editor approaches me, I quickly size up his body language before he has said a word. If he looks genial and relaxed, he probably liked my story. If his face looks set and determined, I know a wrangle over copy is probably ahead. Human beings are exquisitely attuned to social cues and the behavior of others. Such signals tell us what is ahead and give us time to prepare. They tell us about many things that are never explicitly articulated in everyday life. Much of the time, in fact, we do not appreciate how skilled we are at reading social situations. We only realize how ingrained our ability to read social cues is when we see people with serious deficits in social awareness, such as people with autism or schizophrenia. One of the most intriguing theories to emerge in recent years about how our brains perform these feats -- far beyond the ability of the most powerful supercomputers -- is that we have neurons in our brains that essentially act as mirrors of people around us. When we see someone scratch his head or furrow her brow, we instantly have a sense of their mental state, because those actions trigger an equivalent pattern of neural activity in our own minds and allow our brains to quickly deduce the other person's mental state. "These mirror systems give us a fast and intuitive idea of what is going on," said neuroscientist Christian Keysers at the University of Groningen in the Netherlands. © 2006 The Washington Post Company

Keyword: Vision
Link ID: 9385 - Posted: 06.24.2010

By ELIZABETH WEIL When Brian Sullivan — the baby who would before age 2 become Bonnie Sullivan and 36 years later become Cheryl Chase — was born in New Jersey on Aug. 14, 1956, doctors kept his mother, a Catholic housewife, sedated for three days until they could decide what to tell her. Sullivan was born with ambiguous genitals, or as Chase now describes them, with genitals that looked “like a little parkerhouse roll with a cleft in the middle and a little nubbin forward.” Sullivan lived as a boy for 18 months, until doctors at Columbia-Presbyterian Medical Center in Manhattan performed exploratory surgery, found a uterus and ovotestes (gonads containing both ovarian and testicular tissue) and told the Sullivans they’d made a mistake: Brian, a true hermaphrodite in the medical terminology of the day, was actually a girl. Brian was renamed Bonnie, her “nubbin” (which was either a small penis or a large clitoris) was entirely removed and doctors counseled the family to throw away all pictures of Brian, move to a new town and get on with their lives. The Sullivans did that as best they could. They eventually relocated, had three more children and didn’t speak of the circumstances around their eldest child’s birth for many years. As Chase told me recently, “The doctors promised my parents if they did that” — shielded her from her medical history — “that I’d grow up normal, happy, heterosexual and give them grandchildren.” Sullivan spent most of her childhood and young-adult life extremely unhappy, feeling different from her peers though unsure how. Around age 10, her parents told her that she had had an operation to remove a very large clitoris. They didn’t tell her what a clitoris was but said that now things were fine. Copyright 2006 The New York Times Company

Keyword: Sexual Behavior
Link ID: 9384 - Posted: 06.24.2010

The human brain must constantly screen incoming stimuli for relevance. Without such screening, the brain would quickly be overwhelmed by the sheer number of stimuli we experience every day. Some of the most profound stimuli--such as other people's faces--trigger an emotional response, but there are times when fear or even happiness must be kept at bay as the brain works to solve a problem. New research has shown how the brain goes about accomplishing this task. The brain structure known as the amygdala plays a key role in generating and perpetuating emotions such as fear by sending signals into the hypothalamus, which controls the sympathetic nervous system. The amygdala's neighbors in the brain include the anterior cingulate cortex, which neuroscientists think controls various so-called executive processes, such as deciding where attention should be focused. The rostral region of this portion of the cortex (the area on the bottom toward the front) connects directly with the amygdala, and some had speculated that the former might play a role in monitoring emotional states, allowing them to flourish when appropriate but suppressing them when not. Designing a test of this hypothesis, however, had proved challenging. Amit Etkin of Stanford University and his colleagues turned to a classic study of conflict in the brain--the Stroop task--in which the name of a color and the color of the letters in that name either match or not. They tweaked it to create an emotional conflict: pairing faces displaying particular emotional states with words written across them that either identified that state or not, such as “fear” displayed on a smiling face. While being scanned by functional magnetic resonance imaging (fMRI), 19 subjects stared at 148 versions of these pairings, clicking a button to indicate whether that person was happy or afraid. © 1996-2006 Scientific American, Inc.

Keyword: Emotions
Link ID: 9383 - Posted: 06.24.2010

By Andreas K. Engel, Stefan Debener and Cornelia Kranczioch As cognitive neuroscientists, we would like to know what is behind such phenomena: What happens in our brains when we deliberately concentrate on something? Does some mechanism inside our heads decide which information reaches our consciousness--and which does not? And do our intentions, needs and expectations influence what we perceive? Recent research offers some fascinating insights. Psychologists began seeking answers to such questions as long ago as 1890, when American philosopher and psychologist William James wrote about important characteristics of attention in The Principles of Psychology. James concluded that the capacity of consciousness is limited, which is why we cannot pay attention to everything at once. Attention is much more selective: it impels consciousness to concentrate on certain stimuli to process them especially effectively. James and others also distinguished between types of attention. Some of them are "self-created": a penetrating odor, a loud siren, a woman in a bright red dress amid people clad in black. (Many researchers now call this process "bottom-up," because the stimuli battle their way into our consciousness automatically because they are so striking.) Alternatively, we can actively and deliberately control our focus (called "top-down," because higher brain regions are involved at the outset). For example, at a noisy party, we can tune out background noise to listen to the conversation at the next table. © 1996-2006 Scientific American, Inc.

Keyword: Attention
Link ID: 9382 - Posted: 06.24.2010

By Diane Garcia Healthy males often take chances when they're looking for mates, putting on cocky displays, for example. It makes sense that these exploits would tend to attract predators as well, thereby raising the risk of death. But there have been few data to support this theory until a new study of Utah prairie dogs published in next month's issue of the American Naturalist. Utah prairie dogs (Cynomys parvidens) were once an abundant source of food for many grassland predators, including American badgers, coyotes, and golden eagles. But disease, poisoning, and habitat destruction have driven the prairie dogs to the edge of extinction. Behavioral ecologist John Hoogland of the University of Maryland Center for Environmental Science in Frostburg and colleagues have been assessing the impact of predation on prairie dog survival for 11 years. They have observed a 200-member colony in Bryce Canyon National Park, where the team spends each spring perched in 4-meter-high observation towers from dawn to dusk. After marking the prairie dogs with black dye and ear tags, the researchers track their status and behaviors via binoculars and person-to-person radio communication. © 2006 American Association for the Advancement of Science.

Keyword: Sexual Behavior
Link ID: 9381 - Posted: 06.24.2010

By Greg Miller Almost all animals that communicate vocally do it by instinct. The zebra finch is one exception: Young males learn their love songs from their fathers. Now a research team reports the identification of 33 genes related to singing in this songbird. Experts say the work harbingers a new era of using powerful genomic tools to probe the biology of vocal learning--and perhaps reveal the secret of why so few animals do it. Many researchers see parallels between the way birds learn songs and humans learn language. Over the years, they've identified the regions of the zebra finch brain that are involved in song learning and examined the electrical activity of the neurons therein. These studies have yielded many insights into the biological mechanisms of vocal learning, but not at the molecular level. Hoping to take the next step, a team of 20 researchers led by Kazuhiro Wada and Erich Jarvis at Duke University in Durham, North Carolina, cataloged more than 4000 genes expressed in the zebra finch brain. By attaching snippets of these genes to glass slides, they created DNA microarrays that allowed them to compare gene activity in the brains of zebra finches that sang shortly before being killed with gene activity in zebra finches that weren't singing. © 2006 American Association for the Advancement of Science.

Keyword: Language; Genes & Behavior
Link ID: 9380 - Posted: 06.24.2010

Bruce Bower As fossil hunters crossed a dusty slope of Ethiopia's Dikika region on Dec. 10, 2000, one noticed a child's face bones poking out of the ground. Now, after years of painstaking work to remove the ancient individual's skull and some of the other bones from sandstone, researchers have announced that this discovery represents the oldest and most complete fossil child in our evolutionary family. The nearly complete skeleton, missing only the pelvis and a few other bones, comes from a 3-year-old Australopithecus afarensis female who died about 3.3 million years ago, say Zeresenay Alemseged of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, and his colleagues. "This [new fossil] is something you find once in a lifetime," says Zeresenay. The Dikika child's skeleton has not yet been entirely removed from the surrounding rock. Zeresenay's team plans to compare it with Lucy, the 3.2-million-year-old partial skeleton of an adult female A. afarensis, which was unearthed in 1974. The researchers found the child's skeleton between previously dated volcanic-ash layers. A flood apparently covered the child's body in sand and pebbles, protecting it during fossilization. Comparisons of the youngster's teeth with those of people and chimpanzees yielded the estimate of age. ©2006 Science Service.

Keyword: Evolution
Link ID: 9379 - Posted: 06.24.2010

Mt. Sinai School of Medicine epidemiologist Avi Reichenberg and his colleagues compared more than 300,000 parent-child records, and found that men older than 40 were nearly six times more likely to have children with autism than fathers under 30 years old. For men over 40, this translates to a risk of 32 autistic children out of 10,000. For fathers under 30, the risk is 6 out of 10,000, and overall risk was 8.3 cases out of 10,000. Reichenberg stresses that these results show only an increased risk and not a guarantee of autism in children. Reichenberg says that they did not find any link between mothers' ages and autism in their children. Autism is a developmental disorder where children have trouble communicating, find it difficult to socialize with peers, and exhibit repetitious behaviors. According to the Autism Society of America, the disorder is known to affect as many as 1.5 million Americans. Previous research has shown increasing rates of autism, and in his study Reichenberg notes that part of this may be due to improved awareness and detection of the syndrome and part may be a real increase in the autism cases. Some research has looked into a possible link between autism and childhood vaccinations, but a 2004 report from the Institute of Medicine (IOM) of the National Academy of Sciences showed no such link. Recent research has focused on the genetic causes of autism and trying to pinpoint the specific location for the gene. © ScienCentral, 2000-2006.

Keyword: Autism
Link ID: 9378 - Posted: 06.24.2010

By Gretchen Vogel Sociable fruit flies apparently need more sleep than their isolated siblings. The find, reported tomorrow in Science, provides clues about why flies and other animals sleep and what our brains do while we are in dreamland. Although animals of all sorts need sleep to survive, it is still a mystery why we require regular shut-eye. Studies in humans, rats, and other animals have suggested that sleep plays a role in learning and memory--students who have a full night's sleep between training sessions for a new skill learn faster than those who don't, for example (ScienceNOW 14 April, 1998). To see if they could find a link between sleep and nervous-system stimulation, neuroscientist Indrani Ganguly-Fitzgerald of the Neurosciences Institute in San Diego, California, and her colleagues compared the sleep habits of flies housed in groups of 30 or more to those of flies kept in isolation. Despite their simple appearance, flies have rich social lives, she says: "They mate, they fight. They form memories about the interactions they've had, and they make decisions." And, the researchers found, the socialized flies slept significantly more during the day than their isolated counterparts. In fact, the bigger the group, the more sleep the flies needed. Ganguly-Fitzgerald argues that the difference is due to the flies' social life. All that extra stimulation requires extra down-time to process, she says. When the scientists tested flies that couldn't see or smell--and therefore received less sensory input in the socialized conditions--there was no difference between socialized and isolated insects. © 2006 American Association for the Advancement of Science.

Keyword: Sleep
Link ID: 9377 - Posted: 06.24.2010

Roxanne Khamsi Proteins taken from the brains of Alzheimer’s patients and injected into the brains of genetically engineered mice trigger Alzheimer’s-like lesions in the mouse brains, researchers report. The findings suggest that the malformed protein clumps associated with Alzheimer’s disease can “seed” themselves in a way reminiscent of the missfolded proteins in prion diseases such as “mad cow” disease. The exact causes of Alzheimer’s remain a mystery, but it appears that beta-amyloid proteins contribute to the formation of disruptive plaques in the brain. The neurological damage accumulates over years, causing loss of memory, language and other crucial mental skills. Experts studying how beta amyloid might promote plaque formation have speculated that this might happen in a process similar to that in prion diseases. Prion illnesses, such as mad cow disease, are special in that proteins apparently act as the infectious agents, rather than genetic material or a microorganism. In laboratory tests, animals that receive prion proteins develop brain plaques and eventually die as a result. © Copyright Reed Business Information Ltd.

Keyword: Alzheimers; Prions
Link ID: 9376 - Posted: 06.24.2010

Scientists have shown how it may be possible to use the body's own natural stress hormone to soothe the agonies of post-traumatic stress disorder. A team at the University of Texas discovered mice were less agitated by the memory of an electric shock after being given shots of corticosterone. The researchers believe the hormone works by creating new memories to compete with those causing anxiety. Tests are now underway to see if similar hormone shots can help humans. The research appears online in the Journal of Neuroscience. Days after experiencing a traumatic event - a mild electrical shock - mice in the study still showed a fearful response when re-exposed to the place where it happened, a condition that could be a model for post-traumatic stress disorder in humans. But mice receiving the corticosterone shot at the time they "relived" the event experienced a significant drop in that fear. Lead researcher Dr Craig Powell said: "Corticosterone appears to enhance new memories that compete with the fearful memory, thereby decreasing its negative emotional significance." His colleague, Dr Jacqueline Blundell, said: "The natural release of stress hormones during recall of a fearful memory may be a natural mechanism to decrease the negative emotional aspects of the memory. Conversely, patients with post-traumatic stress disorder have blunted stress hormone responses and thus may not decrease fearful memories normally over time." (C)BBC

Keyword: Stress; Learning & Memory
Link ID: 9375 - Posted: 09.21.2006

By Rick Weiss Researchers will report today that cells grown from human embryonic stem cells slowed vision loss when injected into the eyes of rats with a disease similar to macular degeneration, the leading cause of blindness in people older than 55. The experiments do not prove that the cells, obtained through the destruction of human embryos, will work in people. But by showing that the cells have the potential to fill in for failing cells in the retina, experts said, the work may help justify trying the technique in humans. Raymond D. Lund, then at the University of Utah's John A. Moran Eye Center in Salt Lake City, and Robert Lanza of Advanced Cell Technology Inc. (ACT) in Worcester, Mass., started by developing a reliable method for turning embryonic stem cells into retinal pigment epithelium cells, which nourish the light-sensitive "photoreceptor" cells in the eye. In macular degeneration, the pigment cells gradually disappear. The researchers achieved the transformation in all 18 stem cell lines they worked with -- including some provided by the National Institutes of Health and others developed privately at Harvard University and at ACT -- proving that their approach can consistently produce the crucial pigment cells. Then they injected the cells, about 20,000 per eye, into the retinas of 14 rats with a genetic disease similar to macular degeneration. Eight control rats received eye injections without any cells. © 2006 The Washington Post Company

Keyword: Vision; Stem Cells
Link ID: 9374 - Posted: 06.24.2010

Even the tiny, mild-mannered fruit fly can be a little mean sometimes – especially when there’s a choice bit of rotten fruit to fight over. And, like people, some flies have shorter tempers than others. Researchers in the North Carolina Sate University genetics department have identified a suite of genes that affect aggression in the fruit fly Drosophila melanogaster, pointing to new mechanisms that could contribute to abnormal aggression in humans and other animals. The study, led by doctoral student Alexis Edwards in the laboratory of Dr. Trudy Mackay, William Neal Reynolds Professor of Genetics, appears online in PloS Genetics. Feisty flies themselves may not be very scary, but their genes and biochemistry have more in common with those of humans than the casual observer might suspect, and geneticists can subject flies to experiments that simply can’t be done on higher organisms. To measure aggression, the researchers starved male flies for an hour and a half, then gave them a small food droplet and watched them duke it out, counting the number of times a focal fly would chase, kick, box, or flick his wings at other flies.

Keyword: Aggression; Genes & Behavior
Link ID: 9373 - Posted: 06.24.2010

An enzyme found naturally in the brain snips apart the protein that forms the sludge called amyloid plaque that is one of the hallmarks of Alzheimer's disease (AD), researchers have found. They said their findings in mice suggest that the protein, called Cathepsin B (CatB), is a key part of a protective mechanism that may fail in some forms of AD. Also, they said their findings suggest that drugs to enhance CatB activity could break down amyloid deposits, counteracting one of the central pathologies of AD. Li Gan and colleagues published their findings in the September 21, 2006, issue of the journal Neuron, published by Cell Press. Their experiments were prompted by previous studies showing that the cysteine protease CatB--an enzyme that snips apart proteins--closely associated with the amyloid-ß (Aß) protein that forms the amyloid plaques, a hallmark of AD. However, those studies had not determined whether CatB was "good" or "bad"--that is, whether it acted to produce Aß from a longer protein, called amyloid precursor protein (APP), or whether it broke down Aß. In their experiments, Gan and colleagues determined that CatB was the latter--breaking down Aß, apparently to enable other enzymes to further degrade the protein for the cell's protein "garbage deposal" system.

Keyword: Alzheimers
Link ID: 9372 - Posted: 09.21.2006

Daily life requires that people cope with distracting emotions--from the basketball player who must make a crucial shot amidst a screaming crowd, to a salesman under pressure delivering an important pitch to a client. Researchers have now discovered that the brain is able to prevent emotions from interfering with mental functioning by having a specific "executive processing" area of the cortex inhibit activity of the emotion-processing region. The findings also offer insight into how sufferers of post-traumatic stress disorder (PTSD) or depression are unable to control emotional intrusion into their thoughts, said the researchers, Amit Etkin, Joy Hirsch, and colleagues, who reported the discovery. They published their findings in the September 21, 2006, issue of the journal Neuron, published by Cell Press. Their studies were based on previous findings that specific parts of an area of the brain called the anterior cingulate cortex (ACC)--a center for so-called "executive" control of neural processing--are connected to the amygdala. The amygdala is the brain's major center for processing emotional events. The experimental challenge for Etkin, Hirsch, and colleagues was to determine whether this region of the ACC was responsible merely for "monitoring" conflict between cognitive and emotional processing or for actively "resolving" that conflict.

Keyword: Emotions
Link ID: 9371 - Posted: 09.21.2006

Rex Dalton The 3.3-million-year-old bones of a female toddler from Ethiopia are telling scientists a story about the route human ancestors took from the trees to the ground. In today's issue of Nature, an Ethiopian-led international team reports the discovery of a juvenile skeleton of the species commonly known as 'Lucy', or Australopithecus afarensis.1,2 The researchers have named her Selam, after an Ethiopian word for 'peace'. The specimen, which is the oldest and most complete juvenile of a human relative ever found, has features that stand as striking examples of part-way evolution between primitive apes and modern humans. Although many other samples of A. afarensis have been found before, this is the first one reported to come complete with a whole shoulder-blade bone (scapula). In modern humans the scapula has a ridge running horizontally across the top of the bone; in apes the scapula's ridge reaches further down the back, where it can help to throw more muscle into arm action, as would be needed to swing from trees. In the young A. afarensis, the scapula looks to be part-way between. "The animal was losing its capacity to be arboreal — heading right toward being human," says anthropologist Owen Lovejoy of Kent State University in Ohio. ©2006 Nature Publishing Group

Keyword: Evolution
Link ID: 9370 - Posted: 06.24.2010

NORTH GRAFTON, MASS., – In the October 2006 issue of the journal Endocrinology, a collaborative research study by scientists at Cummings School of Veterinary Medicine at Tufts University and the University of Otago Medical School in Dunedin, New Zealand, shows that pregnancy and lactation in rodents produce long-term changes in hormone receptor actions in a mother's brain that may affect maternal behavior as well as her response to stress. "It appears that hormonal changes occurring in rats after they nurse their pups may bring about endocrine and neuroendocrine changes that help produce better mothering skills with each pregnancy and reduce the mother's anxiety levels as she matures," said Robert S. Bridges, PhD, the senior author of this paper and head of the reproductive biology section at Tufts' Cummings School of Veterinary Medicine. In this study, female rats that had undergone a single pregnancy and nursed their offspring displayed higher levels of prolactin hormone receptor activity in the brain, as well as a greater receptor response when treated with prolactin weeks following the last contact with their young. Prolactin is produced by the pituitary gland and plays an established role in a range of reproductive functions, including milk production. The present study is the first to demonstrate long-term changes in the prolactin neural system, a system that Bridges' research group previously identified as crucial for stimulating the establishment of maternal behavior.

Keyword: Sexual Behavior; Hormones & Behavior
Link ID: 9369 - Posted: 06.24.2010

Michael Hopkin Simple stimulation of the brain can cause the mind to play complex and creepy tricks on itself, neurologists have discovered. They found that, by inserting electrodes into a specific part of the brain, they could induce a patient to sense that an illusory 'shadow person' was lurking behind her and mimicking her movements. Doctors treating the patient, a 22-year-old woman with epilepsy, found that when they stimulated a brain region called the left temporoparietal junction, the patient sensed the presence of a sinister figure behind her who copied her actions. They suspect that the effect is due to the mind projecting its own movements onto a phantom figure conjured up by the brain, an effect that is seen in some patients with serious psychiatric conditions. "It was quite astonishing — she definitely realized the 'person' was taking the same posture as she did, but she didn't make the connection," says Olaf Blanke of the École Polytechnique Fédérale de Lausanne in Switzerland, who led the research. "To her it remained a different person, an alien — exactly what you find in schizophrenics." The patient had no history of psychiatric problems. So the results suggest that this type of illusion, despite being an apparently complex psychiatric symptom, can be caused by a very simple switch in the brain. The mechanism might help to explain schizophrenic feelings such as paranoia, alien control, and the notion that parts of one's body belong to somebody else. ©2006 Nature Publishing Group

Keyword: Emotions; Epilepsy
Link ID: 9368 - Posted: 06.24.2010