3/31/2012

Genes for learning, remembering and forgetting


Certain genes and proteins that promote growth and development of embryos also play a surprising role in sending chemical signals that help adults learn, remember, forget and perhaps become addicted, University of Utah biologists have discovered. 


"We found that these molecules and signaling pathways [named Wnt] do not retire after development of the organism, but have a new and surprising role in the adult. They are called back to action to change the properties of the nervous system in response to experience," says biology Professor Andres Villu Maricq, senior author of the new study in the March 30 issue of the journal Cell. 

The study was performed in C. elegans -- the millimeter-long roundworm or nematode -- which has a nervous system that serves as a model for those of vertebrate animals, including humans. 

Because other Wnt pathways in worms are known to work in humans too, the researchers believe that Wnt genes, the Wnt proteins they produce and so-called "Wnt signaling" also are involved in human learning, memory and forgetting. 

"Almost certainly what we have discovered is going on in our brain as well," Maricq says. And because a worm nerve-signal "receptor" in the study is analogous to a human nicotine receptor involved in addiction, schizophrenia and some other mental disorders, some of the genes identified in the worm study "represent possible new targets for treatment of schizophrenia and perhaps addiction," he adds. 

Wnt genes and their proteins already were known to "pattern the development and distribution of organs in the body" during embryo development, and to be responsible for various cancers and developmental defects when mutated, he says. 

Maricq conducted the study with these Utah biologists: doctoral students Michael Jensen and Dane Maxfield; postdoctoral researchers Michael M. Francis, Frederic Hoerndli and Rui Wang; undergraduate Erica Johnson; Penelope Brockie, a research associate professor; and David M. Madsen, a senior research specialist. 

Synapse Plasticity is the Basis of Learning and Memory 

Synapses are the connections between nerve cells (neurons). Nerve signals are transmitted through synapses. Learning and memory concern how these connections are made, broken, strengthened or weakened. Proteins known as receptors are delivered to the synapses or removed from them to strengthen or weaken the connection. 

In the new study, Maricq and colleagues identified a "Wnt signaling pathway" -- a series of genes and the proteins they produce -- that controls the strength of nerve signal transmission from one neuron through a synapse to the next neuron. This allows "plasticity" of synapses -- a key factor in learning, retaining memories and forgetting. 

"The adult nervous system is not a stagnant tissue, but rather dynamic and plastic, with the strength of synapses -- specialized neuron-to-neuron connections -- changing with experience, learning and memory," Maricq says. "It's not a fixed thing, like when you're done making the heart, you're done." 

When synapses and thus incoming nerve signals are strengthened by adding receptors, an organism learns and remembers; when the opposite occurs, the organism forgets, he adds. 

How is that connection strengthened or weakened? When one neuron sends a nerve signal to another neuron, the first neuron releases a chemical known as a neurotransmitter, which moves through the synapse connecting the two cells and attaches or binds to receptors on the surface of the second neuron. 

"You can think of the receptors like amplifiers, like hearing aids," Maricq says. 

The volume of the received nerve signal depends on the number of receptors, which are stored in a supply depot just below the nerve cell's surface. 

The Wnt signaling identified in the new study "tells the depot to put more receptors into the synapse -- or not," says Maricq. 

He emphasizes that the Wnt chemical signal is different than the actual nerve signal carried by a neurotransmitter chemical, which in the new study was acetylcholine. The Wnt signal "is a secondary signal that controls the volume of the neurotransmitter signal," Maricq says. 

Worms Reveal Details of Nerve Signal Volume Control 

By crippling various genes in the worms, the researchers identified the "signaling pathway" by which a Wnt protein in one nerve cell sends a chemical signal to another cell telling it to increase the number of receptors on its surface, thus increasing the strength or volume of nerve signals between the cells. 

This is a microscope image of the roundworm or nematode C. elegans with its nervous system glowing green due to labeling with a green jellyfish protein [Credit: Penelope Brockie, University of Utah]
The type of nerve-signal receptor in the study is an acetylcholine receptor named ACR-16. When researchers crippled the gene that makes the ACR-16 receptor protein, there were not enough receptors, so nerve signals were disrupted and the worms "had uncoordinated movement," Maricq says. "They were semi-paralyzed." 

The scientists found mutations of other genes that also resulted in inadequate ACR-16 receptors and impaired the worms' movement. They discovered such genes belong to the "Wnt signaling pathway" that puts enough receptors on the cell surface so signals can be received. 

Besides ACR-16, genes in that pathway produced proteins named CWN-2 -- which is a Wnt protein -- LIN-17, CAM-1 and DSH-1. 

Here is how that pathway controls the volume of incoming nerve signals: 

1. A neuron releases CWN-2, which binds onto a receptor protein on the signal-receiving cell. That protein is a newly discovered combination of the LIN-17 and CAM-1 proteins. 

2. The LIN-17/CAM-1 protein sends a signal to a protein called disheveled, or DSH-1. 

3. "DSH-1 somehow sends the volume-control signal" that dispatches more ACR-16 receptors from depots inside the second neuron to that cell's surface, thus boosting the volume of the received nerve signal, Maricq says. 

The researchers used a green jellyfish protein to mark the ACR-16 receptors so they were visible under a microscope. When any of the genes in the Wnt signaling pathway were mutant, the scientists could see the green-labeled receptors accumulate under the surfaces of nerve cells instead of moving to the surface. 

Another experiment recorded electrical currents in worm nerve synapses and found it was smaller when any of the Wnt pathway genes were mutated. The smaller current -- reflecting impaired nerve-signal transmission -- explains why the mutant worms were partially paralyzed. 

Human Version of Worm Receptor Tied to Mental Disorders 

The ACR-16 acetylcholine receptor is the worm version of the alpha-7 nicotinic acetylcholine receptor in humans and other vertebrates. Both are similar in structure and function in animals from worms to fruit flies, mice and people. 

The alpha-7 receptor "is important in schizophrenia and a number of different mental disorders, and may have a role in addiction, but we don't understand how it's regulated," Maricq says. 

Many existing psychiatric drugs modify synapse strength. The new study suggests research should be done to show if the same Wnt signaling genes in worms also control alpha-7 receptor levels on human brain cells. If so, new drugs might be developed to target those genes as a way to treat mental disorders, including addiction. 

"Addiction is like learning at a primitive level," Maricq says. "Addiction means that somewhere in your brain, synapses are too strong. So you want more." 

The study was funded by the National Institutes of Health and the American Heart Association. 

Source: University of Utah [March 29, 2012]

3/30/2012

'Backpacking' bacteria help ferry nano-medicines inside humans


To the ranks of horses, donkeys, camels and other animals that have served humanity as pack animals or beasts of burden, scientists are now enlisting bacteria to ferry nano-medicine cargos throughout the human body. They reported on progress in developing these "backpacking" bacteria -- so small that a million would fit on the head of a pin -- in San Diego on March 29 at the 243rd National Meeting & Exposition of the American Chemical Society (ACS). 

Bacterial cells could deliver diagnostics, therapeutics or sensors to where they are needed most in the body ]Credit:Sean Parsons, ACS]
"Cargo-carrying bacteria may be an answer to a major roadblock in using nano-medicine to prevent, diagnose and treat disease," David H. Gracias, Ph.D., leader of the research team said. Gracias explained that nanotechnology is the engineering of ultra-small machines and other devices. These devices generally lack practical self-sustaining motors to move particles of medication, sensors and other material to diseased parts of the body. So why not attach such cargo to bacteria, which have self-propulsion systems, and have them hike around the human body? 

"Currently, it is hard to engineer microparticles or nanoparticles capable of self-propelled motion in well-defined trajectories under biologically relevant conditions," Gracias said. He is with Johns Hopkins University in Baltimore, Maryland. "Bacteria can do this easily, and we have established that bacteria can carry cargo." 

In addition, bacteria can respond to specific biochemical signals in ways that make it possible to steer them to desired parts of the body. Once there, bacteria can settle down, deposit their cargo and grow naturally. Bacteria already live all over the body, particularly in the large intestine, with bacterial cells outnumbering human cells 10-to-1. Despite their popular reputation as disease-causers, there are bacteria in the human body, especially in the intestinal tract, that are not harmful, and the backpackers fall into that category. 

Gracias' bacteria don't really carry little nylon or canvas backpacks. Their "backpacks" are micro- or nano-sized molecules or devices that have useful optical, electrical, magnetic, electrical or medicinal properties. The cargos that the team tested also varied in size, shape and material. So far, the team has loaded beads, nanowires and lithographically fabricated nanostructures onto bacteria. 

Other scientists are seeking to enlist bacteria in transporting nano-cargo. They already have established, for instance, that large numbers of bacteria -- so-called "bacterial carpets" -- can move tiny objects. Gracias' research focuses on attaching one piece of cargo to an individual bacterium, rather than many bacteria to much larger cargo. The bacteria, termed "biohybrid devices," can still move freely, even with the cargo stuck to them. 

"This is very early-stage exploratory research to try and enable new functionalities for medicine at the micro- and nanoscale by leveraging traits from bacteria," explained Gracias. "Our next steps would be to test the feasibility of the backpacking bacteria for diagnosing and treating disease in laboratory experiments. If that proves possible, we would move on to tests in laboratory mice. This could take a few years to complete." 

Source: American Chemical Society [March 29, 2012]

Genetic regulators hijacked by avian and swine flu viruses identified


Researchers at the University of British Columbia have identified a number of tiny but powerful "genetic regulators" that are hijacked by avian and swine flu viruses during human infection. 

This is an illustration showing the influenza A virus, host cell, and cellular microRNAs [Credit: Professor Francois Jean, University of British Columbia]
The discovery, published this week in the Journal of Virology, could reveal new targets for broad-spectrum antivirals to combat current – and perhaps future – strains of influenza A viruses. 

The study is the first to compare the role played by human microRNAs – small molecules that control the expression of multiple genes – in the life cycle of two viruses of continued concern to public health officials around the world. 

"We know that microRNAs are implicated in many types of cancers and other human diseases, but focusing on microRNA signatures in viral infection breaks new ground," says François Jean, Associate Professor in the Department of Microbiology and Immunology and Scientific Director of the Facility for Infectious Disease and Epidemic Research (FINDER) at UBC. 

The study discovered two largely distinct sets of microRNAs involved in pandemic (2009) swine-origin H1N1 virus and the highly pathogenic avian-origin H7N7 strain, with only a small subset of microRNAs involved in the regulation of both infections. 

"Host-virus interplays are certainly complex, but our discovery points to a new level of cross-communication between viruses and the human cells in which they reproduce," notes Jean. "The finding that a significant number of these microRNAs are transported in microparticles – known as exosomes –involved in intercellular communication is also very exciting. It raises the question as to what role these exosome-associated regulators may play in the onset and spread of the flu virus." 

Jean believes that the discovery of the unique microRNA signatures associated with pandemic and deadly flu viruses will assist in developing antiviral treatments that don't run the risk of increasing drug resistance. "Future research on microRNAs could help us develop novel antiviral treatments, adding desperately needed drugs to our current therapeutic repertoire against upcoming flu pandemics." 

Source: University of British Columbia [March 29, 2012]

3/29/2012

With you in the room bacteria counts spike by about 37 million bacteria per hour


A person's mere presence in a room can add 37 million bacteria to the air every hour -- material largely left behind by previous occupants and stirred up from the floor -- according to new research by Yale University engineers. 

Rendering of bacteria. A person's mere presence in a room can add 37 million bacteria to the air every hour -- material largely left behind by previous occupants and stirred up from the floor -- according to new research by Yale University engineers [Credit: © Jezper/Fotolia]
"We live in this microbial soup, and a big ingredient is our own microorganisms," said Jordan Peccia, associate professor of environmental engineering at Yale and the principal investigator of a study recently published online in the journal Indoor Air. "Mostly people are re-suspending what's been deposited before. The floor dust turns out to be the major source of the bacteria that we breathe." 

Many previous studies have surveyed the variety of germs present in everyday spaces. But this is the first study that quantifies how much a lone human presence affects the level of indoor biological aerosols. 

Peccia and his research team measured and analyzed biological particles in a single, ground-floor university classroom over a period of eight days -- four days when the room was periodically occupied, and four days when the room was continuously vacant. At all times the windows and doors were kept closed. The HVAC system was operated at normal levels. Researchers sorted the particles by size. 

Overall, they found that "human occupancy was associated with substantially increased airborne concentrations" of bacteria and fungi of various sizes. Occupancy resulted in especially large spikes for larger-sized fungal particles and medium-sized bacterial particles. The size of bacteria- and fungi-bearing particles is important, because size affects the degree to which they are likely to be filtered from the air or linger and recirculate, the researchers note. 

"Size is the master variable," Peccia said. 

Researchers found that about 18 percent of all bacterial emissions in the room -- including both fresh and previously deposited bacteria -- came from humans, as opposed to plants and other sources. Of the 15 most abundant varieties of bacteria identified in the room studied, four are directly associated with humans, including the most abundant, Propionibacterineae, common on human skin. 

Peccia said carpeted rooms appear to retain especially high amounts of microorganisms, but noted that this does not necessarily mean rugs and carpets should be removed. Extremely few of the microorganisms commonly found indoors -- less than 0.1 percent -- are infectious, he said. 

Still, understanding the content and dynamics of indoor biological aerosols is helpful for devising new ways of improving air quality when necessary, he said. 

"All those infectious diseases we get, we get indoors," he said, adding that Americans spend more than 90 percent of their time inside. 

The researchers have begun a series of similar studies outside the United States. 

The paper's lead author is J. Qian of Yale. Other contributors are D. Hospodsky and N. Yamamoto, both of Yale, and W.W. Nazaroff of the University of California-Berkeley. 

The research was supported by the Alfred P. Sloan Foundation. 

Author: Eric Gershon | Source: Yale University [March 28, 2012]

Placenta on toast? Could we derive benefits from ingesting afterbirth?


Almost all non-human mammals eat placenta for good reasons. Are we missing something? A paper by neuroscientists at the University at Buffalo and Buffalo State College suggests that ingestion of components of afterbirth or placenta -- placentophagia -- may offer benefits to human mothers and perhaps to non-mothers and males. 


They say this possibility does not warrant the wholesale ingestion of afterbirth, for some very good reasons, but that it deserves further study. 

Mark Kristal, PhD, professor of psychology and neuroscience at UB, directs the graduate program in behavioral neuroscience, and has studied placentophagia for more than 40 years. He is recognized as a principle expert in the field. 

Kristal's article "Placentophagia in Human and Nonhuman Mammals: Causes and Consequences," will be published in the March 30 issue of the journal Ecology of Food and Nutrition, which will be devoted to the subject of placentophagia. 

Kristal's co-authors are Jean M. DiPirro, PhD, associate professor, Department of Psychology, Buffalo State College, and Alexis C. Thompson, PhD, research associate professor, UB Department of Psychology and a research scientist in the UB Research Institute on Addictions. 

They point out that the benefits of placenta ingestion (as well as the ingestion of amniotic fluid) by non-human mammalian mothers are significant. It provokes an increase in mother-infant interaction, for instance, and increases the effects of pregnancy-mediated analgesia in the delivering mother. It also potentiates opioid circuits in the maternal brain that facilitate the onset of caretaking behavior, and suppresses postpartum pseudopregnancy, thereby increasing the possibilities for fertilization. 

"Human childbirth is fraught with additional problems for which there are no practical nonhuman animal models," says Kristal, citing postpartum depression, failure to bond and maternal hostility toward the infant. 

He says ingested afterbirth may contain components that ameliorate these problems, but although there have been many anecdotal claims made for human placentophagia, the issue has not been tested empirically. 

"If such studies are undertaken," he says, "the results, if positive, will be medically relevant. If the results are negative, speculations and recommendations will persist, as it is not possible to prove the negative." 

Kristal says there is a current fad of ingesting encapsulated placenta, which mirrors unverified reports in the 1960s and 1970s of people in back-to-nature communes cooking and eating human placentas. The upsurge in recent anecdotal reports of the benefits of taking placenta by new mothers, irrespective of dose, method of preparation, or time course, suggests more of a placebo effect than a medicinal effect. 

"People will do anything," Kristal says, "but we shouldn't read too much significance into reports of such exceptions, even if they are accurate, because they are neither reliable nor valid studies. My own studies found no evidence of the routine practice of placentophagia in other cultures, findings supported by a recent extensive study by anthropologists at the University of Nevada, Las Vegas. 

"The more challenging anthropological question is," he says, "'Why don't humans engage in placentophagia as a biological imperative as so many other mammals apparently do?' because we clearly do not do this as a matter of course today and apparently never have. Perhaps for humans, there is a greater adaptive advantage to not eating the placenta." The paper discusses some possibilities in this regard. 

"Whether or not we learn why humans do not do this, it is important for us to search for the medicinal or behavioral benefits of components of afterbirth for the same reasons that we search for plant-based medicinal substances," Kristal says. 

"The outcome of such a quest need not be an exhortation for women to eat afterbirth, but for scientists to isolate and identify the molecule or molecules that produce the beneficial effect and use it to design pharmacological tools," he says. 

He adds, "In the case of Placental Opioid-Enhancing Factor or POEF and enhanced opioid-mediated analgesia, for instance, we have determined through earlier studies that not only is the effect nonspecific in regard to species, but it is also nonspecific in regard to sex. 

"That means that although males, who in all probability do not make the molecule, have the ability to respond to it," Kristal says. 

Source: University at Buffalo [March 27, 2012]

3/28/2012

Study shows people know more than they think they do


The process of melding individuals into effective, problem-solving groups should involve empowering individuals to realize they have important ideas to share. 

Group of Utah business students involved in problem solving exercise [Credit: David Eccles School of Business]
Dr. Bryan Bonner, an associate professor at the University of Utah's David Eccles School of Business, believes the first step to building successful organizations is deceptively simple: self-realization by each participant of his or her unique knowledge and experience. 

Bonner co-authored "Leveraging Member Expertise to Improve Knowledge Transfer and Demonstrability in Groups" with Dr. Michael Baumann, an associate professor of Psychology at the University of Texas in San Antonio. The study, published in February's edition of the Journal of Personality and Social Psychology, concludes that "for groups to be successful, they must exploit the knowledge of their (individual) members effectively." 

"It doesn't take much. All you have to do is have people sit there for a while and think, 'What is it I already know about this, and how can that help find the solution?'" Bonner says. "People find they often know more than they think they do; they realize that they might not know the whole answer to the problem, but there are a couple things they do know that might help the group come to a solution." 

The researchers used 540 University of Utah undergraduate students, assigning half to three-member groups on one hand, with the remaining 270 participants working as individuals. Their task: arriving at estimates closest to the correct answers to such questions as the elevation of Utah's King's Peak; the weight of the heaviest man in history; the population of Utah; and the minimum driving distance between Salt Lake City and New York City. 

"We solve problems by using the many examples, good and bad, we've gathered through hard-won experience throughout our lives. The problem is that we're not nearly as good at applying old knowledge to new problems as you'd think," Bonner says. "Research over more than a century has tried, without much success, to figure out how we can do a better job." 

Bonner and Baumann, however, are convinced their study shows that "although the sheer amount of brainpower it takes to consistently and effectively transfer learning from old to new is beyond many individuals, groups of people working together can actually be very good at it." 

Source: University of Utah [March 27, 2012]

Dare you protest against God?


Is it OK to protest God's actions—or inactions? This was the key question behind recent studies led by Case Western Reserve University psychologist Julie Exline. 


Many people report having a relationship with God, similar to those relationships in marriage, parenting or friendship. Exline and colleagues found that being assertive with God could actually strengthen that perceived bond and one's faith. 

They report their findings in the journal Psychology of Religion and Spirituality's article, "Anger, Exit and Assertion: Do People See Protest toward God as Morally Acceptable?" 

Using Internet surveys, the research focused on two groups: 358 undergraduates at a research university and 471 participants from a broad-based group of adults. Although a variety of faiths were represented, the analyses focused only on people with some belief in God. 

The researchers discovered if a person views God as cruel, then protest toward God is seen as more acceptable. 

"If God seems like a bully or a tyrant, standing up to God could be seen as an act of courage or even heroism," says Exline. 

But when people see God as a kind and loving authority figure, then protest seems less acceptable. "In this case, protest could appear disrespectful to a good and fair leader," says Exline. 

Exline suggests that it's important to analyze different types of protest. 

The researchers found that many believers think that it's morally OK to be assertive by asking God questions or complaining. But they're less sure about whether anger toward God is acceptable. 

"The larger step of leaving the relationship is clearly seen as wrong by most people of faith," Exline says. "Exiting the relationship can entail outright rejection of God, holding onto anger, questioning God's authority, rebelling, or withdrawing from the relationship." 

"We can think about the parallel to a human relationship," says Exline. "Good relationships usually leave room for honest communications, including some complaint and disagreement. People tend to feel most close and happy with their partners when they have some sense of 'voice' in a relationship. This doesn't mean yelling or screaming, but showing respect and honesty with each other about their feelings—including those of anger and frustration." 

A related question was addressed in the recent Journal of Psychology and Theology's article, "If I Tell Others about My Anger Toward God, How Will They Respond?" Drawing from the same Internet survey of adult believers, she focused only on those who felt some anger toward God. 

If people felt that it was morally OK to feel angry with God, they were more likely to reveal their feelings to others. 

Most people reported supportive responses, Exline says, but it was also common for people to receive unsupportive responses that made them feel judged, ashamed or guilty about their feelings. 

"When people saw others as supportive, they were more likely to report that they had approached God with their feelings—and they were more likely to report strengthened faith in response to the incident," said Exline. "On the other hand, people who reported unsupportive responses from others were more likely to suppress their feelings toward God rather than dealing with them openly. They tended to stay angry with God and were more likely to exit the relationship. They also reported greater use of alcohol and drugs to cope with the problem." 

Exline advises that if someone comes to you and tells you that they are mad at God, the type of response that you provide could be important in terms of shaping what happens. 

"Regardless of whether you think that anger toward God is right or wrong, it's important to respond in a way that helps the other person feel supported rather than shamed," Exline says.  

Source: Case Western Reserve University [March 26, 2012]

3/27/2012

Computer system identifies liars


Inspired by the work of psychologists who study the human face for clues that someone is telling a high-stakes lie, UB computer scientists are exploring whether machines can also read the visual cues that give away deceit. 

In a study of 40 cases, a computer correctly identified liars more than 80 percent of the time, a better rate than humans with the naked eye typically achieve in lie-detection exercises [Credit: Science Photo Library]
Results so far are promising: In a study of 40 videotaped conversations, an automated system that analyzed eye movements correctly identified whether interview subjects were lying or telling the truth 82.5 percent of the time. 

That's a better accuracy rate than expert human interrogators typically achieve in lie-detection judgment experiments, said Ifeoma Nwogu, a research assistant professor at UB's Center for Unified Biometrics and Sensors (CUBS) who helped develop the system. In published results, even experienced interrogators average closer to 65 percent, Nwogu said. 

"What we wanted to understand was whether there are signal changes emitted by people when they are lying, and can machines detect them? The answer was yes, and yes," said Nwogu, whose full name is pronounced "e-fo-ma nwo-gu." 

The research was peer-reviewed, published and presented as part of the 2011 IEEE Conference on Automatic Face and Gesture Recognition. 

Nwogu's colleagues on the study included CUBS scientists Nisha Bhaskaran and Venu Govindaraju, and UB communication professor Mark G. Frank, a behavioral scientist whose primary area of research has been facial expressions and deception. 

In the past, Frank's attempts to automate deceit detection have used systems that analyze changes in body heat or examine a slew of involuntary facial expressions. 

The automated UB system tracked a different trait -- eye movement. The system employed a statistical technique to model how people moved their eyes in two distinct situations: during regular conversation, and while fielding a question designed to prompt a lie. 

People whose pattern of eye movements changed between the first and second scenario were assumed to be lying, while those who maintained consistent eye movement were assumed to be telling the truth. In other words, when the critical question was asked, a strong deviation from normal eye movement patterns suggested a lie. 

Previous experiments in which human judges coded facial movements found documentable differences in eye contact at times when subjects told a high-stakes lie. 

What Nwogu and fellow computer scientists did was create an automated system that could verify and improve upon information used by human coders to successfully classify liars and truth tellers. The next step will be to expand the number of subjects studied and develop automated systems that analyze body language in addition to eye contact. 

Nwogu said that while the sample size was small, the findings are exciting. 

They suggest that computers may be able to learn enough about a person's behavior in a short time to assist with a task that challenges even experienced interrogators. The videos used in the study showed people with various skin colors, head poses, lighting and obstructions such as glasses. 

This does not mean machines are ready to replace human questioners, however -- only that computers can be a helpful tool in identifying liars, Nwogu said. 

She noted that the technology is not foolproof: A very small percentage of subjects studied were excellent liars, maintaining their usual eye movement patterns as they lied. Also, the nature of an interrogation and interrogators' expertise can influence the effectiveness of the lie-detection method. 

The videos used in the study were culled from a set of 132 that Frank recorded during a previous experiment. 

In Frank's original study, 132 interview subjects were given the option to "steal" a check made out to a political party or cause they strongly opposed. 

Subjects who took the check but lied about it successfully to a retired law enforcement interrogator received rewards for themselves and a group they supported; Subjects caught lying incurred a penalty: they and their group received no money, but the group they despised did. Subjects who did not steal the check faced similar punishment if judged lying, but received a smaller sum for being judged truthful. 

The interrogators opened each interview by posing basic, everyday questions. Following this mundane conversation, the interrogators asked about the check. At this critical point, the monetary rewards and penalties increased the stakes of lying, creating an incentive to deceive and do it well. 

In their study on automated deceit detection, Nwogu and her colleagues selected 40 videotaped interrogations. 

They used the mundane beginning of each to establish what normal, baseline eye movement looked like for each subject, focusing on the rate of blinking and the frequency with which people shifted their direction of gaze. 

The scientists then used their automated system to compare each subject's baseline eye movements with eye movements during the critical section of each interrogation -- the point at which interrogators stopped asking everyday questions and began inquiring about the check. 

If the machine detected unusual variations from baseline eye movements at this time, the researchers predicted the subject was lying. 

Source: University at Buffalo [March 26, 2012]

Bone marrow stem cells can improve heart function


A research network led by a Mayo Clinic physician found that stem cells derived from heart failure patients' own bone marrow and injected into their hearts improved the function of the left ventricle, the heart's pumping chamber. Researchers also found that certain types of the stem cells were associated with the largest improvement and warrant further study. 


The results were presented March 26 at the 2012 American College of Cardiology Meeting in Chicago. They will also be published online in the Journal of the American Medical Association. 

This Phase II clinical trial, designed to test this strategy to improve cardiac function, is an extension of earlier efforts in Brazil in which a smaller number of patients received fewer stem cells. For this new network study, 92 patients received a placebo or 100 million stem cells derived from the bone marrow in their hips in a one-time injection. This was the first study in humans to deliver that many bone marrow stem cells. 

"We found that the bone marrow cells did not have a significant impact on the original end points that we chose, which involved reversibility of a lack of blood supply to the heart, the volume of the left ventricle of the heart at the end of a contraction, and maximal oxygen consumption derived through a treadmill test," says Robert Simari, M.D., a cardiologist at Mayo Clinic in Rochester, Minn. He is chairman of the Cardiovascular Cell Therapy Research Network (CCTRN), the network of five academic centers and associated satellite sites that conducted the study. The CCTRN is supported by the National Heart, Lung, and Blood Institute, which also funded the study. 

"But interestingly, we did find that the very simple measure of ejection fraction was improved in the group that received the cells compared to the placebo group by 2.7 percent," Dr. Simari says. Ejection fraction is the percentage of blood pumped out of the left ventricle during each contraction. 

Study principal investigators Emerson Perin, M.D., Ph.D., and James Willerson, M.D., of the Texas Heart Institute, explain that even though 2.7 percent does not seem like a large number, it is statistically significant and means an improvement in heart function for chronic heart failure patients who have no other options. 

"This was a pretty sick population," Dr. Perin says. "They had already had heart attacks, undergone bypass surgery, and had stents placed. However, they weren't at the level of needing a heart transplant yet. In some patients, particularly those who were younger or whose bone marrows were enriched in certain stem cell populations, had even greater improvements in their ejection fractions." 

The average age of study participants was 63. The researchers found that patients younger than 62 improved more. Their ejection fraction improved by 4.7 percent. The researchers looked at the makeup of these patients' stem cells from a supply stored at a biorepository established by the CCTRN. They found these patients had more CD34+ and CD133+ type of stem cells in their mixture. 

"This tells us that the approach we used to deliver the stems cells was safe," Dr. Simari says. "It also suggests new directions for the next series of clinical trials, including the type of patients, endpoints to study and types of cells to deliver." 

Source: Mayo Clinic [March 26, 2012]

3/26/2012

Dental plaque bacteria may trigger blood clots


Oral bacteria that escape into the bloodstream are able to cause blood clots and trigger life-threatening endocarditis. Further research could lead to new drugs to tackle infective heart disease, say scientists presenting their work at the Society for General Microbiology's Spring Conference in Dublin this week. 


Streptococcus gordonii is a normal inhabitant of the mouth and contributes to plaque that forms on the surface of teeth. If these bacteria enter into the blood stream through bleeding gums they can start to wreak havoc by masquerading as human proteins. 

Researchers from the Royal College of Surgeons in Ireland (RCSI) and the University of Bristol have discovered that S. gordonii is able to produce a molecule on its surface that lets it mimic the human protein fibrinogen – a blood-clotting factor. This activates the platelets, causing them to clump inside blood vessels. These unwanted blood clots encase the bacteria, protecting them from the immune system and from antibiotics that might be used to treat infection. Platelet clumping can lead to growths on the heart valves (endocarditis), or inflammation of blood vessels that can block the blood supply to the heart or brain. 

Dr Helen Petersen who is presenting the work said that better understanding of the relationship between bacteria and platelets could ultimately lead to new treatments for infective endocarditis. "In the development of infective endocarditis, a crucial step is the bacteria sticking to the heart valve and then activating platelets to form a clot. We are now looking at the mechanism behind this sequence of events in the hope that we can develop new drugs which are needed to prevent blood clots and also infective endocarditis," she said. 

Infective endocarditis is treated with surgery or by strong antibiotics – which is becoming more difficult with growing antibiotic resistance. "About 30% of people with infective endocarditis die and most will require surgery for replacement of the infected heart valve with a metal or animal valve," said Dr Petersen. "Our team has now identified the critical components of the S. gordonii molecule that mimics fibrinogen, so we are getting closer to being able to design new compounds to inhibit it. This would prevent the stimulation of unwanted blood clots," said Dr Steve Kerrigan from the RCSI. 

The team are also looking more widely at other dental plaque bacteria that may have similar effects to S. gordonii. "We are also trying to determine how widespread this phenomenon is by studying other bacteria related to S. gordonii. What our work clearly shows is how important it is to keep your mouth healthy through regular brushing and flossing, to keep these bacteria in check," stressed Dr Petersen. 

Source: Society for General Microbiology [March 25, 2012]

3/24/2012

Do animals have reflective minds?


According to one of the leading scholars in the field, there is an emerging consensus among scientists that animals share functional parallels with humans' conscious metacognition -- that is, our ability to reflect on our own mental processes and guide and optimize them. 

Scientists concur that when it comes to this Old World macaque: monkey see, monkey do, monkey think about what monkey do, monkey maybe do something else [Credit: University at Buffalo]
In two new contributions to this influential field of comparative psychology, David Smith, PhD, of the University at Buffalo and his fellow researchers report on continuing advances in this domain. 

Smith is a professor in the Department of Psychology at UB, and a member of the university's graduate program in evolution, ecology and behavior and its Center for Cognitive Science. His co-authors on the articles are Justin J. Couchman, PhD, visiting assistant professor of psychology, State University of New York at Fredonia, and Michael J. Beran, PhD, senior research scientist, Language Research Center, Georgia State University. 

In "The Highs and Lows of Theoretical Interpretation in Animal-Metacognition Research," in press at the journal Philosophical Transactions of the Royal Society, Smith, Couchman and Beran examine the theoretical and philosophical problems associated with the attribution of self-reflective, conscious mind to nonverbal animals. 

"The possibility of animal metacognition has become one of the research focal points in comparative psychology today," Smith says, "but, of course, this possibility poses difficult issues of scientific interpretation and inference." In this article, they evaluate the standards that science brings to making difficult interpretations about animal minds, describing how standards have been applied historically and as they perhaps should be applied. The article concludes that macaques do show uncertainty-monitoring capacities that are similar to those in humans. 

The other contribution, "Animal Metacognition," will be published in March by Oxford University Press in the volume "Comparative Cognition: Experimental Explorations of Animal Intelligence." 

In this article, Smith and his colleagues provide a comprehensive review of the current state of the animal-metacognition literature. They describe how Smith inaugurated animal metacognition as a new field of study in 1995 with research on a bottlenosed dolphin. The dolphin assessed correctly when the experimenter's trials were too difficult for him, and adaptively declined to complete those trials. 

The dolphin also showed his own distinctive set of hesitation, wavering and worrying behaviors when the trials were too difficult. In sharp contrast, when the trials were easy, he swam to the responses so fast that he would make a bow-wave around himself that would swamp Smith's delicate electronics. Smith says: "We finally had to buy condoms to protect the equipment." 

Subsequently, Smith and many collaborators also explored the metacognitive capacities of joystick-trained macaques. These Old-World monkeys, native to Africa and Asia, can make specific responses to declare uncertainty about their memory. They can respond, "Uncertain," to gain hints from the experimenters of what to do on the first trial of new tasks. They can even respond, "Uncertain," when their memory has been erased by trans-cranial magnetic stimulation. Accordingly, this second article by Smith and colleagues also supports the consensus that animals share with humans a form of the self-reflective, metacognitive capacity. 

"In all respects," says Smith, "their capacity for uncertainty monitoring, and for responding to uncertainty adaptively, show close correspondence to the same processes in humans. 

"At present," he says, "members of South-American monkey species or New World monkeys have not shown the same robust capacities for uncertainty monitoring, a possible species difference that has intriguing implications regarding the emergence of reflective mind in monkeys, apes and humans." 

Smith's ongoing research in this area is supported by generous grants from both the National Institutes of Health and the National Science Foundation. 

Source: University at Buffalo [March 22, 2012]

3/23/2012

Suppressing feelings of compassion makes people feel less moral


It's normal to not always act on your sense of compassion -- for example, by walking past a beggar on the street without giving them any money. Maybe you want to save your money or avoid engaging with a homeless person. But even if suppressing compassion avoids these costs, it may carry a personal cost of its own, according to a new study published in Psychological Science, a journal of the Association for Psychological Science. After people suppress compassionate feelings, an experiment shows, they lose a bit of their commitment to morality. 


Normally, people assume that ignoring their compassionate feeling doesn't have any cost -- that you can just suppress your sympathy and walk on. But Daryl Cameron and Keith Payne of the University of North Carolina at Chapel Hill, the authors of the paper, suspected that wasn't true. "Compassion is such a powerful emotion. It's been called a moral barometer," Cameron says. A sense of other people's suffering may even be the foundation of morality -- which suggests that suppressing that sense might make people feel less moral. 

The researchers showed each participant in their experiment a slideshow of 15 images of subjects including homeless people, crying babies, and victims of war and famine. Each participant was given one of three tasks. Some were told to try not to feel sympathy, some were told to try not to feel distress (an unpleasant, non-moral feeling), and the rest were told to experience whatever emotions come to them. The instructions were detailed, telling the people who were supposed to suppress an emotion exactly what that emotion was and that they should do their best to eliminate it. 

After each participant watched the slideshow, they were tested on whether they believed that moral rules have to be followed all the time and how much they cared about being a moral person. 

People who had suppressed compassion did, apparently, have a change in their sense of morality: they were much more likely to either care less about being moral or to say that it's all right to be flexible about following moral rules. Cameron thinks this is because suppressing feelings of compassion causes cognitive dissonance that people have to resolve by rearranging their attitudes or beliefs about morality. 

Choosing not to be kind is a common experience. "Many of us do this in daily life," Cameron says -- whether it's declining to give money to a homeless person, changing the channel away from a news story about starving people in a far-off land, or otherwise failing to help someone in need. "In past work, we've shown that people suppress their compassion when faced with mass suffering in natural disasters and genocide. To the degree that suppressing compassion changes how people care about or think about morality, it may put them more at risk for acting immorally." 

Source: Association for Psychological Science [March 15, 2012]

In recognizing faces, the whole is not greater than the sum of its parts


How do we recognize a face? To date, most research has answered "holistically": We look at all the features -- eyes, nose, mouth -- simultaneously and, perceiving the relationships among them, gain an advantage over taking in each feature individually. Now a new study overturns this theory. The researchers -- Jason M. Gold and Patrick J. Mundy of the Indiana University and Bosco S. Tjan of the University of Southern California -- found that people's performance in recognizing a whole face is no better than their performance with each individual feature shown alone. "Surprisingly, the whole was not greater than the sum of its parts," says Gold. 

How do we recognize a face? [Credit: © olly / Fotolia]
The findings appear in the journal Psychological Science, which is published by the Association for Psychological Science. 

To predict each participant's best possible performance in putting together the individual features, the investigators used a theoretical model called an "optimal Bayesian integrator" (OBI). The OBI measures someone's success in perceiving a series of sources of information -- in this case, facial features -- and combines them as if they were using the sources together just as they would when perceiving them one by one. Their score recognizing the combination of features (the whole face) should equal the sum of the individual-feature scores. If the whole-face performance exceeds this sum, it implies that the relationships among the features enhanced the information processing -- that is, "holistic" facial recognition exists. 

In the first experiment participants were shown fuzzy images of three male and three female faces. Then either one feature -- a left or right eye, nose, or mouth -- or all four in proper face-like relationships appeared on the screen. That image would disappear and, if they saw an eye, all six eyes would appear; if a whole face, six whole faces. The participants clicked on the feature or face they'd just seen. In a second experiment, the whole-face images were superimposed on face-shaped ovals -- in case such context helps holistic recognition, as is often claimed. In both experiments, participants' performance with the whole faces was no better than with the isolated features -- and no better than the OBI -- indicating that the facial features were not processed holistically when shown in combination. 

"The OBI offers a clearly defined mathematical framework for studying what historically has been a rather loosely defined set of concepts," says Gold. 

The findings may offer promise in understanding the cognitive disorder prosopagnosia, the inability to recognize faces, and could also help in constructing better face-recognition software for security. But the real value, says Gold, is in basic research. "If you want to understand the complexities of the human mind, then understanding the basic processes that underlie how we perceive patterns and objects is an important part of that puzzle." 

Source: Association for Psychological Science [March 09, 2012]

Happiness is not in the jeans


You may throw on an outfit without much thought in the morning, but your choice is strongly affected by your mood. And the item of casual wear in almost everyone's wardrobe -- denim jeans -- is what most people wear when depressed, new research from psychologists at the University of Hertfordshire reveals. 

Denim jeans is what most people wear when feeling depressed [Credit: © art_zzz / Fotolia]
A study conducted by Professor Karen Pine, co-author of "Flex: Do Something Different, found that what a woman chooses to wear is heavily dependent upon her emotional state."* One hundred women were asked what they wore when feeling depressed and more than half of them said jeans. Only a third would wear jeans when feeling happy. In a low mood a woman is also much more likely to wear a baggy top; 57% of the women said they would wear a baggy top when depressed, yet a mere 2% would wear one when feeling happy. Women also revealed they would be ten times more likely to put on a favorite dress when happy (62%) than when depressed (6%). 

The psychologists conclude that the strong link between clothing and mood state suggests we should put on clothes that we associate with happiness, even when feeling low. 

Professor Pine said: "This finding shows that clothing doesn't just influence others, it reflects and influences the wearer's mood too. Many of the women in this study felt they could alter their mood by changing what they wore. This demonstrates the psychological power of clothing and how the right choices could influence a person's happiness." 

Accessories can make a difference too. The study found that: 

  • Twice as many women said they would wear a hat when happy than when depressed. 
  • Five times as many women said they would wear their favorite shoes when happy (31%) than when depressed (6%). 

The study found that 'happy' clothes -- ones that made women feel good -- were well-cut, figure enhancing, and made from bright and beautiful fabrics. Professor Pine pointed out that these are exactly the features that jeans lack: "Jeans don't look great on everyone. They are often poorly cut and badly fitting. Jeans can signal that the wearer hasn't bothered with their appearance. People who are depressed often lose interest in how they look and don't wish to stand out, so the correlation between depression and wearing jeans is understandable. Most importantly, this research suggests that we can dress for happiness, but that might mean ditching the jeans." 

*FLEX: Do Something Different. How to use the other 9/10ths of your personality, by psychologists Professor Ben (C) Fletcher and Professor Karen Pine, published January 2012 by University of Hertfordshire Press. 

Source: University of Hertfordshire [March 08, 2012]

Women happier in relationships when men feel their pain


Men like to know when their wife or girlfriend is happy while women really want the man in their life to know when they are upset, according to a new study published by the American Psychological Association. 


The study involved a diverse sample of couples and found that men's and women's perceptions of their significant other's empathy, and their abilities to tell when the other is happy or upset, are linked to relationship satisfaction in distinctive ways, according to the article published online in the Journal of Family Psychology. 

"It could be that for women, seeing that their male partner is upset reflects some degree of the man's investment and emotional engagement in the relationship, even during difficult times. This is consistent with what is known about the dissatisfaction women often experience when their male partner becomes emotionally withdrawn and disengaged in response to conflict," said the study's lead author, Shiri Cohen, PhD, of Harvard Medical School. 

Researchers recruited 156 heterosexual couples for the experiment. Of those, 102 came from the Boston area and were younger, urban, ethnically and economically diverse and in a committed but not necessarily married relationship. In an effort to find couples who varied in the ways they resolved conflicts and controlled their emotions, they also looked for couples with a history of domestic violence and/or childhood sexual abuse. The remaining participants, from Bryn Mawr, Pa., were older, suburban and middle-class married couples with strong ties to the community. In all, 71 percent of couples were white, 56 percent were married and their average length of relationship was three-and-a-half years. 

Each participant was asked to describe an incident with his or her partner over the past couple of months that was particularly frustrating, disappointing or upsetting. The researchers' audio recorded the participant making a one- to two-sentence statement summarizing the incident and reaction and then brought the couples together and played each participant's statements. The couples were told to try to come to a better understanding together of what had happened and were given approximately 10 minutes to discuss it while the researchers videotaped them. Following the discussions, the participants viewed the videotape and simultaneously rated their negative and positive emotions throughout, using an electronic rating device. The device had a knob that moved across an 11-point scale that ranged from "very negative" to "neutral" to "very positive." 

Using these ratings, the researchers selected six 30-second clips from the videotape that had the highest rated negative or positive emotions by each partner. The researchers showed the clips to the participants and had them complete questionnaires about their feelings during each segment as well as their perceptions of their partner's feelings and effort to understand them during the discussion. They also measured the participants' overall satisfaction with their relationships and whether each partner considered his or her partner's efforts to be empathetic. 

Relationship satisfaction was directly related to men's ability to read their female partner's positive emotions correctly. However, contrary to the researchers' expectations, women who correctly understood that their partners were upset during the videotaped incident were much more likely to be satisfied with their relationship than if they correctly understood that their partner was happy. Also, when men understood that their female partner was angry or upset, the women reported being happier, though the men were not. The authors suggest that being empathetic to a partner's negative emotions may feel threatening to the relationship for men but not for women. 

The findings also show that the more men and women try to be empathetic to their partner's feelings, the happier they are. The authors suggest that this research should encourage couples to better appreciate and communicate one another's efforts to be empathetic. 

Source: American Psychological Association [March 05, 2012]

Are rich people more unethical?


Since the economic implosion of 2008, the news has been littered with accounts of questionable behavior in boardrooms, corner offices, and other gold-plated spaces. What's not clear from the headlines, however, is whether white-collar criminals like Bernard Madoff are bad apples or extreme examples of a widespread trend. 


A new study may offer a clue to answering that question: A series of experiments conducted by psychologists at the University of California, Berkeley, suggests that people who are socially and financially better-off are more likely to lie, cheat, and otherwise behave unethically compared to individuals who occupy lower rungs of the socioeconomic ladder. 

"Elevated wealth status seems to make you want even more, and that increased want leads you to bend the rules or break the rules to serve your self-interest," says Paul Piff, the lead author of the study and a doctoral candidate in psychology at the university. 

The research team's findings, which appear this week in the Proceedings of the National Academy of Sciences, were drawn from seven separate experiments that together included more than 1,000 people from all walks of life. 

Piff and his colleagues used a variety of measures to gauge the participants' socioeconomic status, such as education levels, annual income (which ranged from about $16,000 to $150,000), and the participants' own perception of their social standing. Regardless of the measure used, however, higher-status people tended to behave in ways that served their own self-interest. 

In the first two experiments, the researchers took to the sidewalks near Berkeley and investigated the relationship between car type -- a reliable, if crude, measure of status -- and driver behavior. 

Drivers with shinier, newer, and more expensive cars were more likely to cut off other motorists at a busy four-way stop and less likely to yield to pedestrians in a crosswalk. Roughly 45% of people driving cars the researchers deemed "high status" ignored a pedestrian, compared to just 30% of those in more modest vehicles. 

In another experiment, a group of college students were asked to rate how willing they were to engage in unethical behavior in various everyday scenarios -- such as taking a ream of printer paper from the office where they work, failing to correct a cashier's error in their favor, or accepting ill-gotten tips about an upcoming exam. 

The results echoed the driving experiments. Students who saw themselves as being higher on the socioeconomic ladder were more likely than their peers to say they would make a less-than-honorable decision in the hypothetical situations. 

These findings don't show that unethical behavior is somehow ingrained in people of higher status, Piff says. However, he says, they do suggest that small changes in a situation or environment cause people of varying backgrounds to express their instincts and values in different ways. 

"We're not saying you should distrust the rich, or the rich are corrupt," says Piff. "Instead, this highlights the disparities in social environments -- that different positions occupied give rise to almost natural tendencies and divergent social values." 

What accounts for this divergence? The independence offered by financial security may foster a sense of entitlement and a lack of concern for others, the authors suggest. On a more concrete level, affluent people may be more likely to get away with misbehavior (because they are less supervised at work, for example), and they may be more willing to take ethical risks because they have the resources to bail themselves out -- both literally and figuratively -- if they get caught. 

Then again, there may be a simpler explanation: greed. The researchers found that unethical behavior was closely related to positive feelings about greed. Although the connection appeared to be strongest among high-status individuals, even lower-status individuals were more prone to ethical lapses if they felt that greed was good. 

Study participants, for instance, were more likely to cheat on a dice game or mislead a hypothetical job candidate about an available position if they agreed strongly with a series of greed-related statements, such as "To be a successful person in this society, it is important to make use of every opportunity" and "It is not morally bad to think first of one's own benefit and not other people's." 

The study findings aren't black-and-white. Robert Gore, Ph.D., an associate professor of psychology at Alliant International University, in San Francisco, says that class, status, and ethics are all slippery concepts that are difficult to pin down in experiments, even those -- like the driving ones -- that make use of real-world situations. 

"Not everyone who is coded as relatively high social class drives a luxury car," Gore says. "Luxury car drivers are a subset of the well-to-do, and we all know people who drive cars they can't really afford." 

In addition, Gore says, experiments that test people's willingness to behave unethically only say so much about their day-to-day behavior. "This study really shows that people who identify as higher social class are more likely to admit unethical behavior," he says. "It's not clear whether they actually behave worse or just claim to." 

Piff and his colleagues acknowledge the limitations of the study. At the same time, Piff says, the fact that seven different experiments all produced similar results helps "eliminate alternative explanations." And, as the study notes, the pattern held after the researchers took into account factors such as age, sex, ethnicity, and religious and political affiliations, all of which are associated with ethics and values. 

Author: Amanda Gardner | Source: Health Com [February 27, 2012]

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