Scientists at the University of Liverpool have discovered that the human brain favours familiar-looking faces when choosing a potential partner. The research team found that people find familiar faces more attractive than unfamiliar ones. They also found that the human brain holds separate images of both male and female faces and reacts to them differently depending on how familiar it is with their facial features. Dr Anthony Little, from the University's School of Biological Sciences, examined whether early visual experience of male and female faces affected later preferences. The research team asked over 200 participants to view a number of human faces that had been digitally manipulated to change their facial characteristics. Dr Little said: "We found that participants preferred the face that they were most visually familiar with. In one of the tests we showed participants a block of faces with wide-spaced eyes and then asked them to compare these with a face that had narrow-spaced eyes. We found that participants preferred the face with wide-spaced eyes, suggesting that the brain connects familiarity with attraction." The team also asked participants to judge the same preferred facial features in those of the opposite sex. Participants who were shown male faces with wide-spaced eyes preferred this trait in subsequent male faces but not in female faces.

Keyword: Sexual Behavior
Link ID: 7830 - Posted: 09.01.2005

Just as travelers figure out which restaurant is good by the numbers of cars in the parking lot, bumblebees decide which flowers to visit by seeing which ones already have bee visitors. Bumblebees that watched other bees forage on green artificial flowers were twice as likely to choose the green flowers over orange flowers when it was their turn to forage, according to new research. The finding is the first demonstration that insects can learn by just watching the behavior of other insects. "Studying a variety of different animals -- everything from chimpanzees to bees -- that show some kind of social learning, will give us a better understanding of how social learning occurs," said behavioral ecologist Bradley D. Worden of The University of Arizona in Tucson. "One of the cool things we're finding out from bees is that complex behavior and advanced forms of learning can come from small brains." Worden, a postdoctoral research associate in UA's department of ecology and evolutionary biology, conducted his work on the brainy bees with Daniel R. Papaj, a UA professor of ecology and evolutionary biology. The team's report has been released online and will be published in an upcoming issue of Biology Letters of the Royal Society. The National Science Foundation funded the research. Charles Darwin was one inspiration for the study because he wrote about the possibility that honeybees were watching and learning from bumblebees, Worden said.

Keyword: Learning & Memory
Link ID: 7829 - Posted: 09.01.2005

One of the neural oddities of "declarative" memory--the recall of past things and events--is that some experiments have shown that recognizing a familiar object is accompanied by a reduction in activity of the brain's memory centers in the medial temporal lobe. Such a reduction seems counterintuitive, since remembering seems to be a positive event. Now, researchers led by Anthony D. Wagner, Brian D. Gonsalves, and Itamar Kahn of Stanford University have documented this reduced activity in humans and have demonstrated that the magnitude of the dip corresponds with the familiarity of the objects. In their experiments reported in the September 1, 2005, issue of Neuron, the researchers asked volunteers to look at series of faces as the subjects' brains were scanned using either of two techniques. One was functional magnetic resonance imaging (fMRI), which gives information on the location and amount of activation of brain regions, and the other was magnetoencephalography (MEG), which reports the precise timing of brain responses. The technique of fMRI uses harmless magnetic fields and radio waves to map blood flow in the brain, which reflects brain activity, and MEG detects the infinitesimal magnetic fields generated by brain electrical activity. The researchers asked the subjects to rate their familiarity with each face as "remembering" if they strongly recalled the face, "knowing" if they had a feeling of recognizing the face, or "new" if they didn't recall seeing the face before.

Keyword: Learning & Memory
Link ID: 7828 - Posted: 09.01.2005

Roxanne Khamsi Deciding between a risky financial investment and a safe one sets two parts of the brain into competition, say researchers in California. As centres for pleasure and anxiety battle it out, a simple brain scan of the two can actually predict what a person will chose to do a few seconds before they do it: when joy beats worry in our brain, a risky decision is made. Studies of how the mind handles risky behaviour have highlighted a number of neural hotspots. One is a peanut-sized region of the brain called the nucleus accumbens, which is loaded with the molecule dopamine and becomes active in anticipation of pleasure. The nucleus accumbens is known to play a role in the addictive affect of drugs. Another region, known as the anterior insula, is stimulated in anticipation of a bad sensation. This area lights up in those predicting the onset of physical pain, and in generally anxious individuals. Neuroscientist Brian Knutson of Stanford University and his colleague Camelia Kuhnen sought to compare how these two brain regions interact by asking 20 volunteers to play an investment game for a cash reward. ©2005 Nature Publishing Group

Keyword: Emotions; Drug Abuse
Link ID: 7827 - Posted: 06.24.2010

Michael Hopkin Good news for lovers of extra-virgin olive oil: besides being delicious on salads, it also contains a compound that mimics the effects of ibuprofen. So a Mediterranean-style diet might give you the supposed long-term benefits of that drug, such as a reduced cancer risk. A daily dose of 50 g or 4 tablespoons of olive oil confers the equivalent of around 10% of the recommended ibuprofen dose for adult pain relief, say researchers led by Paul Breslin of the Monell Chemical Senses Center at the University of the Sciences in Philadelphia, who discovered the effect. So although it won't cure a headache, it may give you some of the long-term benefits of repeated ibuprofen use, including helping to ward off Alzheimer's. The compound, called oleocanthal, acts in the same way as ibuprofen to stifle components of a pain pathway called the prostaglandin system. This is in spite of the two chemicals' very different structures, the team reports in Nature1. The compound should be present in any extra-virgin oil, Breslin says. But concentrations will vary depending on a range of factors, such as the variety of olive, and the age of the olives at pressing. ©2005 Nature Publishing Group

Keyword: Pain & Touch
Link ID: 7826 - Posted: 06.24.2010

WASHINGTON, - The first comprehensive comparison of the genetic blueprints of humans and chimpanzees shows our closest living relatives share perfect identity with 96 percent of our DNA sequence, an international research consortium reported today. In a paper published in the Sept. 1 issue of the journal Nature, the Chimpanzee Sequencing and Analysis Consortium, which is supported in part by the National Human Genome Research Institute (NHGRI), one of the National Institutes of Health (NIH), describes its landmark analysis comparing the genome of the chimp (Pan troglodytes) with that of human (Homo sapiens). "The sequencing of the chimp genome is a historic achievement that is destined to lead to many more exciting discoveries with implications for human health," said NHGRI Director Francis S. Collins, M.D., Ph.D. "As we build upon the foundation laid by the Human Genome Project, it’s become clear that comparing the human genome with the genomes of other organisms is an enormously powerful tool for understanding our own biology." The chimp sequence draft represents the first non-human primate genome and the fourth mammalian genome described in a major scientific publication. A draft of the human genome sequence was published in February 2001, a draft of the mouse genome sequence was published in December 2002 and a draft of the rat sequence was published in March 2004. The essentially complete human sequence was published in October 2004.

Keyword: Genes & Behavior; Evolution
Link ID: 7825 - Posted: 06.24.2010

By Robert C. Cowen When an inert placebo acts like a drug, is it just a psychological illusion? Or is it a real biological effect? Research reported last week suggests that it's both. The mere belief that they had received a pain killer was enough to release the brain's natural painkilling endorphins in the patients tested, scientists say. This opens a new line of research into the placebo puzzle. The effect has been demonstrated often enough to show that some patients appear to benefit from such belief. But there hasn't been enough evidence to convince skeptics that anything more than the so-called power of suggestion is at work. That's changing. "The findings of this study are counter to the common thought that the placebo effect is purely psychological due to suggestion and that it does not represent a real physical change." says University of Michigan neuroscientist Jon-Kar Zubieta. He is principal author of the study published Aug. 24 in The Journal of Neuroscience. Some mind/body effects are well known. Adrenaline flows when firefighters go into action. The sight of a lion induces physical changes that prepare a zebra to flee. Humans often experience a similar fight-or-flight reaction to a perceived threat. But it's been too much of a stretch for many neuroscientists to accept that belief in fake medication can produce medical benefits that can be objectively verified. Copyright © 2005 The Christian Science Monitor.

Keyword: Pain & Touch
Link ID: 7824 - Posted: 06.24.2010

By Jonathan Picker, Ph.D. Schizophrenia appears to be a disorder of development that results from a series of neurological insults from fetal life onward (Rapoport et al., 2005). Whether or not schizophrenia manifests appears to be the result of a conglomeration of these factors, both genetic and environmental in origin (Sullivan et al., 2003), as shown in the Figure. No one factor appears to be most significant in the genesis of schizophrenia. This is evident despite the very significant resources that have been expended in the search to understand the patho-etiology of schizophrenia. This may be because there are multiple factors involved; multiple different disorders with varied pathologies present with the schizophrenia phenotype; or a combination of both. The search to uncover the pathological basis to schizophrenia has, however, provided broad generalizations that have yielded more specific etiological candidates as a result of newer, more powerful methodologies, particularly those resulting from the Human Genome Project. Interestingly, some of the genetic candidates identified providing explanatory models that may incorporate identified environmental risk factors. Risk for schizophrenia appears to begin as early as the first trimester in pregnancy, with exposure to influenza associated with increased risk of later developing schizophrenia (Brown et al., 2004). Other prenatal factors are also implicated in the second and third trimesters. © 2005 Psychiatric Times. All rights reserved.

Keyword: Schizophrenia
Link ID: 7823 - Posted: 06.24.2010

By Stephen V. Faraone, Ph.D., and Philip Asherson, MRCPsych, Ph.D. Although attention-deficit/hyperactivity disorder is frequently misunderstood as caused by normal childhood energy, boring classrooms, or overstressed parents and teachers, several decades of research show ADHD to be a valid disorder with a neurobiological basis (Faraone, in press). Genetic studies have played a leading role in clarifying the biological basis of the disorder. Family studies have documented familial transmission; adoption studies show this transmission occurs through biological, not adoptive relationships; and twin studies show that ADHD is highly heritable such that genes account for about 75% of the disorder's variability in the population (Faraone et al., in press). With a prevalence of 8% to 12% (Faraone et al., 2003), it is among the most common of psychiatric disorders. Given this strong evidence from epidemiologic studies, molecular genetic studies have begun the search for genes that increase susceptibility to ADHD. Two general approaches have been used. Genome scan linkage studies scan the entire genome in search of regions that might harbor susceptibility genes. They do not require a prior hypothesis about which genes cause the disorder. In contrast, candidate gene studies nominate specific genes based on a biological theory about their putative role. They use the method of association to test these prior hypotheses. © 2005 Psychiatric Times. All rights reserved.

Keyword: ADHD; Genes & Behavior
Link ID: 7822 - Posted: 06.24.2010

DALLAS – – Vagus nerve stimulation (VNS) therapy, a treatment recently approved by the Food and Drug Administration for treatment-resistant depression, produced a positive response in more than 25 percent of patients in a national, yearlong study led by UT Southwestern Medical Center psychiatrists. Sixteen percent to 20 percent of the study group experienced total remission. Results of the study, led by Dr. A. John Rush, vice chairman for research in psychiatry at UT Southwestern, appear in the September issue of Biological Psychiatry. Findings from two additional related studies also are included in the issue. VNS therapy, which the FDA approved for treatment of epileptic seizures in 1997 and for depression in July, has been studied in clinical trials for treatment-resistant depression since 1998. VNS therapy includes surgical implantation of a small battery-operated pulse generator – similar to a pacemaker – in a patient's left upper chest. Thin, flexible wires from the device are tunneled into the neck and send mild, intermittent pulses to the neck's left vagus nerve. The vagus nerve in turn delivers these pulses about every five minutes to the areas of the brain involved in the regulation of mood, motivation, sleep, appetite and other symptoms relevant to depression.

Keyword: Depression
Link ID: 7821 - Posted: 06.24.2010

By Tracy Staedter, Discovery News — Bats are one of the few terrestrial animals able to navigate through the air using sound. Now a bionic head that mimics a bat's sensory talent is not only helping scientists understand how the animals maneuver but could also lead to much more advanced sonar-based navigation methods for land-based robots. "There are some niches for using in-air sonar and bats have found one niche," said Herbert Peremans, head of the Active Perception Lab of the University of Antwerp and coordinator for the EU-financed CIRCE (Chiroptera Inspired Robotic Cephaloid) bat head project. In the world of robotics, though, sonar has been largely relegated to underwater vehicles. That's because sound travels much further underwater than light or radio waves and is not limited by the murky darkness of deep water. On land, however, sound waves peter out after traveling only 10 or 15 meters and the results returned by commercially available sonar sensors cannot compare to vision- or laser-based systems. But more than 700 species of bats build their survival success on sonar and Peremans and his colleagues think that if they can find out how, they could apply that knowledge to land-based robots. Copyright © 2005 Discovery Communications Inc.

Keyword: Hearing
Link ID: 7820 - Posted: 06.24.2010

US scientists say they have hard evidence to show that certain emotions can cause flare ups of asthma. The University of Wisconsin-Madison team discovered activity in brain areas linking the two in asthmatics who read emotive words. One brain region has a role in obtaining information about disease symptoms while another processes emotions. Their findings appear in Proceedings of the National Academy of Sciences. Dr Richard Davidson and his team asked six patients with mild asthma to take part in their experiments. Each was shown three different categories of words - asthma-related words such as "wheeze", negative but non-asthma-related words such as "loneliness" and neutral words such as "curtains". At the same time, the volunteers were given known triggers of asthma to inhale, such as ragweed or dust-mite extract. Meanwhile, their brain responses were monitored using functional magnetic resonance imaging. Two brain regions - the anterior cingulate cortex and the insula - showed increased activity when the asthma-related words were heard compared with the other word types. Furthermore, the increased brain activity was linked to body function signals from the inhaled allergens. (C)BBC

Keyword: Emotions; Neuroimmunology
Link ID: 7819 - Posted: 08.30.2005

By Marc Siegel America has its killer bugs, but Americans don't, as a rule, express great concern about them: Pneumonia, which killed 63,000 Americans in 2000, draws little public comment. Until 2003, when the flu deaths of 20 U.S. children early in the season were widely publicized, Americans didn't worry much about influenza either, despite the tens of thousands of deaths attributed to that disease each year. In comparison, relatively minor threats are widely feared. First publicized in 2002, West Nile virus was perceived as a great threat, though it killed only 284 people in the United States. In 2003, when severe acute respiratory syndrome, or SARS, emerged in Asia, there were only 7,000 cases in the world and fewer than 100 in the United States. No one in the United States died of SARS, but a lot of people worried. Many patients called my internal medicine practice in New York convinced that the slightest cough was SARS. People were afraid to sit next to an Asian person or to eat in a Chinese restaurant. The connection between excess worry and increased disease risk is not just hypothetical. Numerous studies have shown a link between ill health and stress reported by patients. Each terror alert, too, triggers a wave of often unjustified fear. Anthrax infected 22 people through the U.S. mail in the fall of 2001, killing five. Yet 30,000 people began taking the powerful antibiotic Cipro, many indiscriminately and without a doctor's prescription. © 2005 The Washington Post Company

Keyword: Stress; Neuroimmunology
Link ID: 7818 - Posted: 06.24.2010

US scientists are developing a "glowing" dye to help spot signs in the brain of early dementia. The dye works by binding to the brain areas damaged in Alzheimer's disease and giving off a fluorescent glow that can be seen with a brain scan. The Massachusetts Institute of Technology team have made a prototype that they hope will soon be ready to use clinically. Their findings appear in the journal Angewandte Chemie. Currently, doctors make a diagnosis of Alzheimer's based on a patient's symptoms, but these normally occur much later when the condition has been present for some time. The only way to say for sure that the cause is actually Alzheimer's is after the patient has died, by doing a post-mortem and looking for the characteristic signs the disease leaves in the brain - deposits or plaques made of the protein amyloid. This makes it difficult for doctors looking for a cure for Alzheimer's because they cannot monitor whether candidate drugs are having a direct effect on disease progression in the brain. This prompted Professor Timothy Swager and his team, along with colleagues from the University of Pittsburgh, to make their prototype. When they tested their dye, called NIAD-4, in living mice they found it was able to bind to and "light up" brain amyloid plaques, similar to those seen in people with Alzheimer's. (C)BBC

Keyword: Alzheimers; Brain imaging
Link ID: 7817 - Posted: 08.30.2005

Berkeley - Though humans may never match the tracking ability of dogs, we apparently have the ability to sniff out and locate odors, according to a new study by scientists from the University of California, Berkeley. Student volunteers presented with odors to one nostril or the other could reliably discern where the odor was coming from, and functional magnetic resonance images of their brains showed that the brain is set up to pay attention to the difference between what the left and right nostrils sense, much the way it can localize sounds by contrasting input from the ears. "It has been very controversial whether humans can do egocentric localization, that is, keep their head motionless and say where the spatial source of an odor is," said study coauthor Noam Sobel, associate professor of psychology at UC Berkeley and a member of the campus's Helen Wills Neuroscience Institute. "It seems that we have this ability and that, with practice, you could become really good at it." In future experiments, UC Berkeley biophysics graduate student Jess Porter and Sobel plan to train volunteers to track odors in the field and test the limits of odor localization in humans. Porter, Sobel and their colleagues reported the results in the August 18 issue of the journal Neuron.

Keyword: Chemical Senses (Smell & Taste)
Link ID: 7816 - Posted: 08.30.2005

Waltham, Mass. – In a new study, Brandeis University researchers conclude that older adults with mild-to-moderate hearing loss may expend so much cognitive energy on hearing accurately that their ability to remember spoken language suffers as a result. The study, published in Current Directions in Psychological Science, showed that even when older adults could hear words well enough to repeat them, their ability to memorize and remember these words was poorer in comparison to other individuals of the same age with good hearing. "There are subtle effects of hearing loss on memory and cognitive function in older adults," said lead author Arthur Wingfield, Nancy Lurie Marks Professor of Neuroscience at the Volen National Center for Complex Systems at Brandeis University. "The effect of expending extra effort comprehending words means there are fewer cognitive resources for higher level comprehension." "This extra effort in the initial stages of speech perception uses processing resources that would otherwise be available for downstream operations, such as encoding the material in memory or performing higher-level comprehension operations," explained co-authors Patricia A. Tun and Sandra L. McCoy.

Keyword: Hearing; Language
Link ID: 7815 - Posted: 06.24.2010

OAK BROOK, Ill.--The amount of blood flowing into the brain may play a larger role in the development of dementia than previously believed, according to a study in the September issue of the journal Radiology. Researchers from Leiden University Medical Center in the Netherlands used magnetic resonance imaging (MRI) to examine the brains of elderly patients with and without dementia related to Alzheimer's or Parkinson's disease. As expected, MR images showed that the patients with late-onset dementia had more brain damage compared with young adults and with seniors who had optimal cognitive function. But researchers found that the late-onset dementia group also had a much lower rate of blood flow to the brain than the other two groups. "Our findings not only support the hypothesis that vascular factors contribute to dementia in the elderly, they are highly suggestive that a diminished cerebral blood flow indeed causes brain damage," said Aart Spilt, M.D., a Leiden radiology resident and lead author of the study. "This gives us a clue to the genesis of dementia." Dementia is a loss of cognitive functions, such as thinking, remembering and reasoning, that interferes with normal activities. Although many conditions can produce these symptoms, Alzheimer's disease is the most common cause of dementia. Some patients with Parkinson's disease also develop dementia.

Keyword: Alzheimers
Link ID: 7814 - Posted: 08.30.2005

WASHINGTON - A new study has found that opiate drugs such as morphine leave animals more vulnerable to stress. This means that stress and opiates are in a vicious cycle: Not only does stress trigger drug use, but in return the drug leaves animals more vulnerable to stress. The study, conducted at the University of New South Wales, helps to explain why people who use opiates such as heroin have very high rates of anxiety problems, including post-traumatic stress disorder, even after they stop using. That emotional fragility can also make them more likely to start using again. The study appears in the current issue of the journal Behavioral Neuroscience, which is published by the American Psychological Association (APA). Understanding how opiate users respond to and cope with stress may lead to better treatment and help prevent relapses. Co-author Gavan McNally, PhD, notes that heroin is the most commonly used illicit opiate, followed perhaps by morphine. In medical settings, pethidine, fentanyl, morphine and codeine are typically used. McNally and his colleagues conducted four experiments with rats, injecting them with either morphine or saline solution every day for 10 days. Then, either one or seven days after the final injection, they gently restrained each rat for 30 minutes as a form of stress. The team then measured the rats' biological responses to the restraint stress. They also studied behaviors that reflect anxiety, checking the rats' levels of social interaction and general activity. The researchers tested anxiety responses for three different dose levels and different durations of exposure (0, 1, 5 or 10 days).

Keyword: Stress; Drug Abuse
Link ID: 7813 - Posted: 08.29.2005

While their friends enjoy the latest hit tunes, people who are tone deaf – in scientific terms, suffering from amusia – are excluded from the fun, unable to tell one note from another. The disorder can be congenital, present from birth, or acquired following injury to the brain. In an article published online August 29, 2005, in the Annals of Neurology (www.interscience.wiley.com/journal/ana), researchers now report the first objective measurement of the brain deficit in congenital amusia. The findings may have implications both for amusia and for speech learning disabilities, according to lead study author Isabelle Peretz, Ph.D., of the University of Montreal. Peretz and collaborators at the University of Helsinki assessed brain cell responses to tones across different brain areas using electroencephalography (EEG). Compared to control subjects, people with congenital amusia show abnormal brain activity in the right half of the brain, consistent with earlier findings by Peretz's group and others. It may be possible to compensate for amusia by training pitch discrimination abilities. "However, it is likely that the intervention will only be effective in a 'plastic' brain, in children. We see no sign of improvement in adults," said Peretz.

Keyword: Hearing
Link ID: 7812 - Posted: 06.24.2010

MADISON -- The mere mention of a stressful word like "wheeze" can activate two brain regions in asthmatics during an attack, and this brain activity may be associated with more severe asthma symptoms, according to a study by University of Wisconsin-Madison researchers and collaborators. The study, which appears in the Proceedings of the National Academy of Sciences (Online, August 29, 2005), reveals a functional link between emotion processing centers in the brain and certain physiological processes relevant to disease. UW-Madison psychology professor Richard Davidson, an expert on emotions; and UW-Madison medicine professor William Busse, an expert on asthma; are senior co-authors on the study. Melissa Rosenkranz, a graduate student at the UW-Madison Laboratory for Affective Neuroscience, is the lead author. "While this study was small, it shows how important specific brain circuits can be in modulating inflammation," says Davidson, director of the affective neuroscience laboratory and the Waisman Laboratory for Functional Brain Imaging and Behavior. "The data suggest potential future targets for the development of drugs and behavioral interventions to control asthma and other stress-responsive disorders."

Keyword: Neuroimmunology; Emotions
Link ID: 7811 - Posted: 08.29.2005