It has been known for some time that house mice (Mus musculus) produce ultrasonic vocalizations (USVs) during courtship but it has generally been assumed that these are no more than squeaks. However, recent spectrographic analyses have revealed that USVs are complex and show features of song. Although the vocalizations are inaudible to human ears, when playbacks of recorded songs are slowed down their similarity to bird song becomes striking. Frauke Hoffmann, Kerstin Musolf and Dustin Penn of the University of Veterinary Medicine, Vienna's Konrad Lorenz Institute of Ethology aimed to learn what type of information is contained in males' songs for the discerning ear of the female mouse to detect. Their initial studies, the first to study song in wild mice, confirmed that males emit songs when they encounter a females' scent and that females are attracted to males' songs. Additionally, the scientists discovered that females are able to distinguish siblings from unrelated males by their songs – even though they had previously never heard their brothers sing.
In their recent studies, Penn's group recorded and analysed the courtship calls of wild-caught male house mice for the first time, using digital audio software to examine parameters such as duration, pitch and frequency. They found that males' songs contain "signatures" or "fingerprints" that differ from one individual to another. Moreover, they confirmed that the songs of siblings are very similar to one another compared to the songs of unrelated males, which helps explains how females can distinguish unrelated males. This finding could potentially lead us to understand how female mice avoid inbreeding.
Interestingly, in some species of birds the males with the most complex songs appear to be most successful at attracting females. Further studies are needed to determine whether the complexity of male mouse vocalizations has an effect on females that is similar to that of "sexy syllables" in birds.
The vocalizations of wild house mice differ significantly from those of inbred strains of laboratory mice. Wild male mice produce more syllables within high frequency ranges than laboratory mice, a result that is consistent with other studies that find genetic effects on mouse song. "It seems as though house mice might provide a new model organism for the study of song in animals," says Dustin Penn. "Who would have thought that?"
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Friday, January 27
by
Dr. A
on Fri 27 Jan 2012 08:08 PM CST
by
Dr. A
on Fri 27 Jan 2012 07:46 PM CST
Distrust and paranoia about government has a long history, and the feeling that there is a conspiracy of elites can lead to suspicion for authorities and the claims they make. For some, the attraction of conspiracy theories is so strong that it leads them to endorse entirely contradictory beliefs, according to a study in the current Social Psychological and Personality Science (published by SAGE). People who endorse conspiracy theories see authorities as fundamentally deceptive. The conviction that the "official story" is untrue can lead people to believe several alternative theories-despite contradictions among them. "Any conspiracy theory that stands in opposition to the official narrative will gain some degree of endorsement from someone who holds a conspiracist worldview," according to Michael Wood, Karen Douglas and Robbie Sutton of the University of Kent.
To see if conspiracy views were strong enough to lead to inconsistencies, the researchers asked 137 college students about the death of Princess Diana. The more people thought there "was an official campaign by the intelligence service to assassinate Diana," the more they also believed that "Diana faked her own death to retreat into isolation." Of course, Diana cannot be simultaneously dead and alive. The researchers wanted to know if the contradictory beliefs were due to suspicion of authorities, so they asked 102 college students about the death of Osama bin Laden (OBL). People who believed that "when the raid took place, OBL was already dead," were significantly more likely to also believe that "OBL is still alive." Since bin Laden is not Schrödinger's cat, he must either be alive or dead. The researchers found that the belief that the "actions of the Obama administration indicate that they are hiding some important or damaging piece of information about the raid" was responsible for the connection between the two conspiracy theories. Conspiracy belief is so potent that it will lead to belief in completely inconsistent ideas. "For conspiracy theorists, those in power are seen as deceptive-even malevolent-and so any official explanation is at a disadvantage, and any alternative explanation is more credible from the start," said the authors. It is no surprise that fear, mistrust, and even paranoia can lead to muddled thinking; when distrust is engaged, careful reasoning can coast on by. "Believing Osama is still alive," they write, 'is no obstacle to believing that he has been dead for years." Thursday, January 26
by
Dr. A
on Thu 26 Jan 2012 07:30 PM CST
Feeling like you're part of the gang is crucial to the human experience. All people get stressed out when we're left out. A new study published in Psychological Science, a journal of the Association for Psychological Science, finds that a feeling of inclusion can come from something as simple as eye contact from a stranger.
Psychologists already know that humans have to feel connected to each other to be happy. A knitting circle, a church choir, or a friendly neighbor can all feed that need for connection. Eric D. Wesselmann of Purdue University wanted to know just how small a cue could help someone feel connected. He cowrote the study with Florencia D. Cardoso of the Universidad Nacional de Mar del Plata in Argentina, Samantha Slater of Ohio University, and Kipling D. Williams of Purdue. "Some of my coauthors have found, for example, that people have reported that they felt bothered sometimes even when a stranger hasn't acknowledged them," Wesselmann says. He and his authors came up with an experiment to test that. The study was carried out with the cooperation of people on campus at Purdue University. A research assistant walked along a well-populated path, picked a subject, and either met that person's eyes, met their eyes and smiled, or looked in the direction of the person's eyes, but past them—past an ear, for example, "looking at them as if they were air," Wesselmann says. When the assistant had passed the person, he or she gave a thumbs-up behind the back to indicate that another experimenter should stop that person. The second experimenter asked, "Within the last minute, how disconnected do you feel from others?" People who had gotten eye contact from the research assistant, with or without a smile, felt less disconnected than people who had been looked at as if they weren't there. "These are people that you don't know, just walking by you, but them looking at you or giving you the air gaze—looking through you—seemed to have at least momentary effect," Wesselmann says. Other research has found that even being ostracized by a group you want nothing to do with, like the Ku Klux Klan, can make people feel left out, so it's not surprising that being pointedly ignored can have the same effect. "What we find so interesting about this is that now we can further speak to the power of human social connection," Wesselmann says. "It seems to be a very strong phenomenon." Wednesday, January 25
by
Dr. A
on Wed 25 Jan 2012 09:32 PM CST
Narcissism has a higher health cost for men
The personality trait narcissism may have an especially negative effect on the health of men, according to a recent study published in PLoS ONE. "Narcissistic men may be paying a high price in terms of their physical health, in addition to the psychological cost to their relationships," says Sara Konrath, a University of Michigan psychologist who co-authored the study. Earlier studies by Konrath and others have shown that the level of narcissism is rising in American culture, and that narcissism tends to be more prevalent among males. The personality trait is characterized by an inflated sense of self-importance, overestimations of uniqueness, and a sense of grandiosity. For the new study, Konrath and colleagues David Reinhard of the University of Virginia, and William Lopez and Heather Cameron of the University of Michigan examined the role of narcissism and sex on cortisol levels in a sample of 106 undergraduate students. Cortisol, which can be measured through saliva samples, is a widely used marker of physiological stress. The researchers measured cortisol levels at two points in time in order to assess baseline levels of the hormone, which signals the level of activation of the body's key stress response system, the hypothalamic-pituitary-adrenal (HPA) axis. Participants were not asked to complete any tasks that would elevate their stress. Elevated levels of cortisol in a relatively stress-free situation would indicate chronic HPA activation, which has significant health implications, increasing the risk of cardiovascular problems. To assess participants' narcissism, the researchers administered a 40-item narcissism questionnaire that measures five different components of the personality trait. Two of these components are more maladaptive, or unhealthy – exploitativeness and entitlement; and the other three are more adaptive, or healthy – leadership/authority, superiority/arrogance, and self-absorption/self-admiration. "Even though narcissists have grandiose self-perceptions, they also have fragile views of themselves, and often resort to defensive strategies like aggression when their sense of superiority is threatened," says Reinhard. "These kinds of coping strategies are linked with increased cardiovascular reactivity to stress and higher blood pressure, so it makes sense that higher levels of maladaptive narcissism would contribute to highly reactive stress response systems and chronically elevated levels of stress." Reinhard, Konrath and colleagues found that the most toxic aspects of narcissism were indeed associated with higher cortisol in male participants, but not in females. In fact, unhealthy narcissism was more than twice as large a predictor of cortisol in males as in females. They also found that there was no relationship between healthy narcissism and cortisol in either males or females. "These findings extend previous research by showing that narcissism may not only influence how people respond to stressful events, but may also affect how they respond to their regular day-to-day routines and interactions," says Konrath. "Our findings suggest that the HPA axis may be chronically activated in males high in unhealthy narcissism, even without an explicit stressor." Why should narcissism affect males differently? "Given societal definitions of masculinity that overlap with narcissism – for example, the belief that men should be arrogant and dominant – men who endorse stereotypically male sex roles and who are also high in narcissism may feel especially stressed," Konrath suggests. In future research, she hopes to examine why narcissism is not as physiologically taxing for women as it is for men, and also to examine the potential links between maladaptive narcissism and other physiological responses related to stress and poor coping, including inflammatory markers such as C-Reactive Protein.
by
Dr. A
on Wed 25 Jan 2012 09:29 PM CST
With growing concern that excessive levels of fructose may pose a great health risk – causing high blood pressure, kidney disease and diabetes – researchers at the University of Colorado School of Medicine, along with their colleagues at the University of Florida, set out to see if two common sweeteners in western diets differ in their effects on the body in the first few hours after ingestion. The study, recently published in the journal Metabolism, took a closer look at high fructose corn syrup (HFCS) and table sugar (sucrose) and was led by Dr MyPhuong Le (now a postdoctoral fellow at the University of Colorado) and Dr Julie Johnson, a Professor of Pharmacogenomics at the University of Florida.
Both HFCS and sucrose have historically been considered to have nearly identical effects on the body. But this study finds that indeed there is a difference between the two. They found that the makeup of the sugars resulted in differences in how much fructose was absorbed into the circulation, and which could have potential impact on one's health. Sucrose is 50 percent fructose and 50 percent glucose that is bonded together as a disaccharide (complex carbohydrate) and HFCS is a mixture of free fructose (55%) and free glucose (45%). It's the difference in fructose amount that appears to create the ill health effects on the body. Their study was conducted at the University of Florida, where they evaluated 40 men and women who were given 24 ounces of HFCS- or sugar-sweetened soft drinks. Careful measurements showed that the HFCS sweetened soft drinks resulted in significantly higher fructose levels than the sugar-sweetened drinks. Fructose is also known to increase uric acid levels that have been implicated in blood pressure, and the HFCS-sweetened drinks also resulted in a higher uric acid level and a 3 mm Hg greater rise in systolic blood pressure. Dr Richard Johnson, a coauthor in the study and Chief of the Division of Renal Diseases and Hypertension at the University of Colorado, commented "Although both sweeteners are often considered the same in terms of their biological effects, this study demonstrates that there are subtle differences. Soft drinks containing HFCS result in slightly higher blood levels of fructose than sucrose-sweetened drinks, "said Johnson. "The next step is for new studies to address whether the long-term effects of these two sweeteners are different."
by
Dr. A
on Wed 25 Jan 2012 09:11 PM CST
Max Planck researchers reveal the structure of the cellular protein degradation machinery
Mate competition by males over females is common in many animal species. During mating season male testosterone levels rise, resulting in an increase in aggressive behavior and masculine features. Male bonobos, however, invest much more into friendly relationships with females. Elevated testosterone and aggression levels would collide with this increased tendency towards forming pair-relationships. Bonobos are among the closest living relatives of humans. Like other great apes they live in groups made up of several males and females. Contrary to other ape species however, male bonobos do not, in general, outrank female individuals and do not dominate them in mating contexts. This constellation suggests that the selection for typically masculine behavioral patterns like aggression, dominance and intrasexual competition are met with antagonistic forces: On one hand it is advantageous if a male outcompetes a fellow male. This, however, implies that there is increased aggression and an elevated level of testosterone in high-ranking males. On the other hand – as dominance relations between the sexes are rather balanced in bonobos – it is likely that males benefit from having friendly pair-relationships with female individuals. Studies with birds and rodents show that a tendency towards forming pair-relationships correlates with lower male aggression rates and testosterone levels. In a current study, Martin Surbeck, Gottfried Hohmann, Tobias Deschner and colleagues of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, found that in wild bonobos high-ranking males were more aggressive and their mating success was higher when compared to lower-ranking males. Contrary to other species in which males compete fiercely over access to females, there was no correlation between dominance status or aggression with testosterone levels. In addition, the researchers found that high-ranking males invested more often than lower-ranking group members into friendly relationships with females. This suggests that these friendly relationships between the sexes are associated with lower male testosterone levels. "Our study suggests that in bonobos – as in in humans – intersexual friendships result in hormonal patterns that we know from species in which male individuals are actively participating in raising their young and in which the two sexes enter lasting pair-relationships", says Martin Surbeck.
by
Dr. A
on Wed 25 Jan 2012 08:04 PM CST
In cultures that permit men to take multiple wives, the intra-sexual competition that occurs causes greater levels of crime, violence, poverty and gender inequality than in societies that institutionalize and practice monogamous marriage. That is a key finding of a new University of British Columbia-led study that explores the global rise of monogamous marriage as a dominant cultural institution. The study suggests that institutionalized monogamous marriage is rapidly replacing polygamy because it has lower levels of inherent social problems. "Our goal was to understand why monogamous marriage has become standard in most developed nations in recent centuries, when most recorded cultures have practiced polygyny," says UBC Prof. Joseph Henrich, a cultural anthropologist, referring to the form of polygamy that permits multiple wives, which continues to be practiced in some parts of Africa, Asia, the Middle East and North America. "The emergence of monogamous marriage is also puzzling for some as the very people who most benefit from polygyny – wealthy, powerful men – were best positioned to reject it," says Henrich, lead author of the study that is published today in the journal Philosophical Transactions of the Royal Society. "Our findings suggest that that institutionalized monogamous marriage provides greater net benefits for society at large by reducing social problems that are inherent in polygynous societies."
Considered the most comprehensive study of polygamy and the institution of marriage, the study finds significantly higher levels rape, kidnapping, murder, assault, robbery and fraud in polygynous cultures. According to Henrich and his research team, which included Profs. Robert Boyd (UCLA) and Peter Richerson (UC Davis), these crimes are caused primarily by pools of unmarried men, which result when other men take multiple wives. "The scarcity of marriageable women in polygamous cultures increases competition among men for the remaining unmarried women," says Henrich, adding that polygamy was outlawed in 1963 in Nepal, 1955 in India (partially), 1953 in China and 1880 in Japan. The greater competition increases the likelihood men in polygamous communities will resort to criminal behavior to gain resources and women, he says. According to Henrich, monogamy's main cultural evolutionary advantage over polygyny is the more egalitarian distribution of women, which reduces male competition and social problems. By shifting male efforts from seeking wives to paternal investment, institutionalized monogamy increases long-term planning, economic productivity, savings and child investment, the study finds. Monogamy's institutionalization has been assisted by its incorporation by religions, such as Christianity. Monogamous marriage also results in significant improvements in child welfare, including lower rates of child neglect, abuse, accidental death, homicide and intra-household conflict, the study finds. These benefits result from greater levels of parental investment, smaller households and increased direct "blood relatedness" in monogamous family households, says Henrich, who served as an expert witness for British Columbia's Supreme Court case involving the polygamous community of Bountiful, B.C. Monogamous marriage has largely preceded democracy and voting rights for women in the nations where it has been institutionalized, says Henrich, the Canadian Research Chair in Culture, Cognition and Evolution in UBC's Depts. of Psychology and Economics. By decreasing competition for younger and younger brides, monogamous marriage increases the age of first marriage for females, decreases the spousal age gap and elevates female influence in household decisions which decreases total fertility and increases gender equality.
by
Dr. A
on Wed 25 Jan 2012 07:58 PM CST
Brain scans of people under the influence of the psilocybin, the active ingredient in magic mushrooms, have given scientists the most detailed picture to date of how psychedelic drugs work. The findings of two studies being published in scientific journals this week identify areas of the brain where activity is suppressed by psilocybin and suggest that it helps people to experience memories more vividly.
In the first study, published today in Proceedings of the National Academy of Sciences (PNAS), 30 healthy volunteers had psilocybin infused into their blood while inside magnetic resonance imaging (MRI) scanners, which measure changes in brain activity. The scans showed that activity decreased in "hub" regions of the brain – areas that are especially well-connected with other areas. The second study, due to be published online by the British Journal of Psychiatry on Thursday, found that psilocybin enhanced volunteers' recollections of personal memories, which the researchers suggest could make it useful as an adjunct to psychotherapy. Professor David Nutt, from the Department of Medicine at Imperial College London, the senior author of both studies, said: "Psychedelics are thought of as 'mind-expanding' drugs so it has commonly been assumed that they work by increasing brain activity, but surprisingly, we found that psilocybin actually caused activity to decrease in areas that have the densest connections with other areas. These hubs constrain our experience of the world and keep it orderly. We now know that deactivating these regions leads to a state in which the world is experienced as strange." The intensity of the effects reported by the participants, including visions of geometric patterns, unusual bodily sensations and altered sense of space and time, correlated with a decrease in oxygenation and blood flow in certain parts of the brain. The function of these areas, the medial prefrontal cortex (mPFC) and the posterior cingulate cortex (PCC), is the subject of debate among neuroscientists, but the PCC is proposed to have a role in consciousness and self-identity. The mPFC is known to be hyperactive in depression, so psilocybin's action on this area could be responsible for some antidepressant effects that have been reported. Similarly, psilocybin reduced blood flow in the hypothalamus, where blood flow is increased during cluster headaches, perhaps explaining why some sufferers have said symptoms improved under psilocybin. In the British Journal of Psychiatry study 10 volunteers viewed written cues that prompted them to think about memories associated with strong positive emotions while inside the brain scanner. The participants rated their recollections as being more vivid after taking psilocybin compared with a placebo, and with psilocybin there was increased activity in areas of the brain that process vision and other sensory information. Participants were also asked to rate changes in their emotional well-being two weeks after taking the psilocybin and placebo. Their ratings of memory vividness under the drug showed a significant positive correlation with their well-being two weeks afterwards. In a previous study of 12 people in 2011, researchers found that people with anxiety who were given a single psilocybin treatment had decreased depression scores six months later. Dr Robin Carhart-Harris, from the Department of Medicine at Imperial College London, the first author of both papers, said: "Psilocybin was used extensively in psychotherapy in the 1950s, but the biological rationale for its use has not been properly investigated until now. Our findings support the idea that psilocybin facilitates access to personal memories and emotions. "Previous studies have suggested that psilocybin can improve people's sense of emotional well-being and even reduce depression in people with anxiety. This is consistent with our finding that psilocybin decreases mPFC activity, as many effective depression treatments do. The effects need to be investigated further, and ours was only a small study, but we are interested in exploring psilocybin's potential as a therapeutic tool." The researchers acknowledged that because the participants in this study had volunteered after having previous experience of psychedelics, they may have held prior assumptions about the drugs which could have contributed to the positive memory rating and the reports of improved well-being in the follow-up. Functional MRI measures brain activity indirectly by mapping blood flow or the oxygen levels in the blood. When an area becomes more active, it uses more glucose, but generates energy in rapid chemical reactions that do not use oxygen. Consequently, blood flow increases but oxygen consumption does not, resulting in a higher concentration of oxygen in blood in the local veins. In the PNAS study, the volunteers were split into two groups, each studied using a different type of fMRI: 15 were scanned using arterial spin labelling (ASL) perfusion fMRI, which measures blood flow, and 15 using blood-oxygen level-dependent (BOLD) fMRI. The two modalities produced similar results, strongly suggesting that the observed effects were genuine. Wednesday, January 11
by
Dr. A
on Wed 11 Jan 2012 10:52 PM CST
Using marijuana carries legal risks, but a new study shows that the consequences of occasionally lighting up do not include long-term loss of lung function, according to a new study by University of Alabama at Birmingham researchers published in the January 11, 2012, issue of the Journal of the American Medical Association.
Marijuana is the most commonly used illicit drug in the United States, according to the National Survey on Drug Use and Health. In 2009, 16.7 million Americans ages 12 and older reported using marijuana at least once in the month prior to being surveyed. In addition, since 1996, 16 states and Washington, D.C., have legalized the medical use of marijuana to help manage the symptoms of many diseases, including cancer, AIDS and glaucoma. "With marijuana use increasing and large numbers of people who have been and continue to be exposed, knowing whether it causes lasting damage to lung function is important for public-health messaging and medical use of marijuana," says the study's senior author, Stefan Kertesz, M.D., associate professor in the UAB Division of Preventive Medicine and with the Center for Surgical, Medical and Acute Care Research and Transitions at the Veterans Affairs Medical Center in Birmingham. Kertesz says it's long been known that marijuana smoke has many irritant chemicals found in tobacco smoke and can cause lung irritation, wheezing and cough immediately after use; however, the research on long-term effects on lung function have inconsistencies. Using a large national database, the research team compared the lung function of marijuana and tobacco smokers during a 20-year period. The data revealed that tobacco smoke had exactly the effect shown in all prior studies — increasing a person's cumulative exposure to cigarettes results in loss of air flow and lung volumes; the opposite was true for marijuana smoke. "At levels of marijuana exposure commonly seen in Americans, occasional marijuana use was associated with increases in lung air flow rates and increases in lung capacity," Kertesz says. "Those increases were not large, but they were statistically significant. And the data showed that even up to moderately high-use levels — one joint a day for seven years — there is no evidence of decreased air-flow rates or lung volumes." Kertesz cautions that smoking marijuana is not an avenue to better lung health. "It's not enough of an increase that would make you feel better," he says "Healthy adults can blow out 3 to 4 liters of air in one second. The amount of gain, on average, from marijuana is small, 50 ccs or roughly a fifth of a can of coke. So it's not something that would be noticeable." Also, Kertesz says, the increase does not hold steadfast over time. "The relationship changes for people who get to high levels of lifetime exposure," he says. "At that point, the data suggests there is a decline in lung air-flow rate. There also may be other damaging effects that don't manifest until extremely high levels of exposure; we did not have enough very heavy marijuana smokers in this study to determine this." To perform their analysis, Kertesz and a research team from other universities looked at data from the Coronary Artery Risk Development in Young Adults Study. CARDIA, funded by the National Heart, Lung and Blood Institute, is a long-term research project involving more than 5,000 black and white men and women from Birmingham, Chicago, Minneapolis and Oakland, designed to examine the development and determinants of cardiovascular disease and its risk factors. Participants were recruited when they were ages 18-30 and followed from 1985 to 2006. The researchers looked closely at the reported use of both marijuana and tobacco and asked participants repeatedly during years of follow-up about their use of these substances. Marijuana and tobacco use were both commonly reported — 37 percent said they used marijuana at some point during the study. This is similar, the researchers say, to what many Americans have said in other national surveys. As part of the CARDIA protocol, participants' lung function was measured for air flow and lung volume at years 0, 2, 5, 10 and 20 using standard pulmonary function tests. The air flow measure is the amount of air you can blow out of your lungs in one second after taking the deepest breath possible. The volume measure is the total amount of air you can blow out after taking the deepest breath possible. Lead author, Mark J. Pletcher, M.D., of the Department of Epidemiology and Biostatistics, and Department of Medicine at the University of California, San Francisco, who led the statistical analysis, says what sets this study apart from any others is both the number of participants and duration of the study. "This is not the first study to show that marijuana has a complicated relationship with lung function. However, the size of the study and the long duration of follow-up help us to paint a clearer picture of the ways in which the relationship changes over time," he says. As a final note, Kertesz clarified that the study did not examine other ways in which smoking marijuana could affect a person's health and insisted this study does not advocate the use of marijuana. "Marijuana is still an illegal drug, and it has many complicated effects on the human body and its function," he says. "In our findings we see hints of harm in pulmonary function with heavy use, and other studies have shown that marijuana use increases a user's likelihood of a heart attack, according to the American Heart Association, and impairs the immune system's ability to fight disease, according to the National Institute on Drug Abuse." Tuesday, January 10
by
Dr. A
on Tue 10 Jan 2012 09:15 AM CST
A new study finds that the inevitable cognitive decline we all face starts earlier than we originally thought. Christie Nicholson reports.
by
Dr. A
on Tue 10 Jan 2012 08:32 AM CST
Nicotine replacement therapies (NRTs) designed to help people stop smoking, specifically nicotine patches and nicotine gum, do not appear to be effective in helping smokers quit long-term, even when combined with smoking cessation counseling, according to a new study by researchers at Harvard School of Public Health (HSPH) and the University of Massachusetts Boston. The study appears January 9, 2012 in an advance online edition of Tobacco Control and will appear in a later print issue.
"What this study shows is the need for the Food and Drug Administration, which oversees regulation of both medications to help smokers quit and tobacco products, to approve only medications that have been proven to be effective in helping smokers quit in the long-term and to lower nicotine in order to reduce the addictiveness of cigarettes," said co-author Gregory Connolly, director of the Center for Global Tobacco Control at HSPH. In the prospective cohort study the researchers, including lead author Hillel Alpert, research scientist at HSPH, and co-author Lois Biener of the University of Massachusetts Boston's Center for Survey Research, followed 787 adult smokers in Massachusetts who had recently quit smoking. The participants were surveyed over three time periods: 2001-2002, 2003-2004, and 2005-2006. Participants were asked whether they had used a nicotine replacement therapy in the form of the nicotine patch (placed on the skin), nicotine gum, nicotine inhaler, or nasal spray to help them quit, and if so, what was the longest period of time they had used the product continuously. They also were asked if they had joined a quit-smoking program or received help from a doctor, counselor, or other professional. The results showed that, for each time period, almost one-third of recent quitters reported to have relapsed. The researchers found no difference in relapse rate among those who used NRT for more than six weeks, with or without professional counseling. No difference in quitting success with use of NRT was found for either heavy or light smokers. "This study shows that using NRT is no more effective in helping people stop smoking cigarettes in the long-term than trying to quit on one's own," Alpert said. He added that even though clinical trials (studies) have found NRT to be effective, the new findings demonstrate the importance of empirical studies [emphasis added] regarding effectiveness when used in the general population. Biener said that using public funds to provide NRT to the population at large is of questionable value, particularly when it reduces the amount of money available for smoking interventions shown in previous studies to be effective, such as media campaigns, promotion of no smoking policies, and tobacco price increases. Smoking cessation medications have been available over the counter since 1996, yet U.S. Centers for Disease Control and Prevention statistics show that the previous adult smoking rate decline and quitting rates have stalled in the past five years.
by
Dr. A
on Tue 10 Jan 2012 08:18 AM CST
UCSF analysis suggests penny-per-ounce tax on sugary beverages would prevent heart disease, stroke and diabetes and save billions in healthcare costs
Every year, Americans drink 13.8 billion gallons of soda, fruit punch, sweet tea, sports drinks, and other sweetened beverages—a mass consumption of sugar that is fueling soaring obesity and diabetes rates in the United States. Now a group of scientists at the University of California, San Francisco (UCSF), San Francisco General Hospital and Trauma Center (SFGH) and Columbia University have analyzed the effect of a nationwide tax on these sugary drinks. They estimate slapping a penny-per-ounce tax on sweetened beverages would prevent nearly 100,000 cases of heart disease, 8,000 strokes, and 26,000 deaths every year. "You would also prevent 240,000 cases of diabetes per year," said Kirsten Bibbins-Domingo, an associate professor of medicine and of epidemiology and biostatistics at UCSF and acting director of the Center for Vulnerable Populations at SFGH. In addition to $13 billion in direct tax revenue, Bibbins-Domingo and her colleagues estimated that such a tax would save the public $17 billion per year in healthcare-related expenses due to the decline of obesity-related diseases. "Our hope is that these types of numbers are useful for policy makers to weigh decisions," she said. The High Cost of High Calorie Drinks Consumption of beverages high in calories but poor in nutritional value is the number one source of added sugar and excess calories in the American diet. Sugar- sweetened drinks are linked to type 2 diabetes and weight gain. The U.S. Centers for Disease Control and Prevention listed reducing the intake of these beverages as one of its chief obesity prevention strategies in 2009, and several states and cities, including California and New York City, are already considering such taxes. The analysis by Bibbins-Domingo and her colleagues is among the first study to generate concrete estimates of the health benefits and cost savings of such a tax. They modeled these benefits by taking into account how many sodas and sugary beverages Americans drink every year and estimating how much less they would consume if a penny-per-ounce tax were imposed on these drinks. Economists have estimated that such a tax would reduce consumption by 10 to 15 percent over a decade. They then modeled how this reduction would play out in terms of reducing the burdens of diabetes, heart disease and their associated healthcare costs. Saturday, January 7
by
Dr. A
on Sat 07 Jan 2012 04:23 PM CST
A new UCSF analysis of tobacco industry documents shows that Philip Morris USA manipulated data on the effects of additives in cigarettes, including menthol, obscuring actual toxicity levels and increasing the risk of heart, cancer and other diseases for smokers. Tobacco industry information can't be taken at face value, the researchers conclude. They say their work provides evidence that hundreds of additives, including menthol, should be eliminated from cigarettes on public health grounds. The article is published in PLoS Medicine.
In the new, independent study, the scientists reassessed data from Philip Morris' "Project MIX," which detailed chemical analyses of smoke and animal toxicology studies of 333 cigarette additives. Philip Morris, the nation's largest tobacco company, published its findings in 2002. By investigating the origins and design of Project MIX, the UCSF researchers conducted their own inquiry into the Philip Morris results. They stressed that many of the toxins in cigarette smoke substantially increased after additives were added to cigarettes. They also found, after obtaining evidence that additives increased toxicity, that tobacco scientists adjusted the protocol for presenting their results in a way that obscured these increases. "We discovered these post-hoc changes in analytical protocols after the industry scientists found that the additives increased cigarette toxicity by increasing the number of fine particles in the cigarette smoke that cause heart and other diseases," said senior author Stanton A. Glantz, PhD, UCSF professor of medicine and director of the Center for Tobacco Control Research and Education at UCSF. "When we conducted our own analysis by studying additives per cigarette – following Philip Morris' original protocol -- we found that 15 carcinogenic chemicals increased by 20 percent or more," he said. Additionally, in the independent study, the researchers discovered the reason behind Philip Morris' failure to identify many toxic effects in animal studies: its studies were too small. "The experiment was too small in terms of the number of rats analyzed to statistically detect important changes in biological effects," Glantz said. "Philip Morris underpowered its own studies." The results of "Project MIX" were first published as four papers in a 2002 edition of Food and Chemical Toxicology, a journal whose editor and many members of its editorial board had financial ties to the tobacco industry. While Philip Morris was trying to get the papers published, the company scientist who led Project Mix sent an email (.pdf) to a colleague describing the peer review process as "an inside job." In the new study, the researchers used documents made public as a result of litigation against the tobacco industry. The documents are available to the public through UCSF's Legacy Tobacco Documents Library. Thursday, January 5
by
Dr. A
on Thu 05 Jan 2012 11:59 PM CST
Dogs pick up not only on the words we say but also on our intent to communicate with them, according to a report published online in the Cell Press journal Current Biology on January 5. The findings might help to explain why so many people treat their furry friends like their children; dogs' receptivity to human communication is surprisingly similar to the receptivity of very young children, the researchers say. "Increasing evidence supports the notion that humans and dogs share some social skills, with dogs' social-cognitive functioning resembling that of a 6-month to 2-year-old child in many respects," said József Topál of the Hungarian Academy of Sciences. "The utilization of ostensive cues is one of these features: dogs, as well as human infants, are sensitive to cues that signal communicative intent." Those cues include verbal addressing and eye contact, he explained. Whether or not dogs rely on similar pathways in the brain for processing those cues isn't yet clear.
Topál's team presented dogs with video recordings of a person turning toward one of two identical plastic pots while an eye tracker captured information on the dogs' reactions. In one condition, the person first looked straight at the dog, addressing it in a high-pitched voice with "Hi dog!" In the second condition, the person gave only a low-pitched "Hi dog" while avoiding eye contact. The data show that the dogs were more likely to follow along and look at the pot when the person first expressed an intention to communicate. "Our findings reveal that dogs are receptive to human communication in a manner that was previously attributed only to human infants," Topál said. As is often the case in research, the results will undoubtedly confirm what many dog owners and trainers already know, the researchers say. Notably, however, it is the first study to use eye-tracking techniques to study dogs' social skills. "By following the eye movements of dogs, we are able to get a firsthand look at how their minds are actually working," Topál said. "We think that the use of this new eye-tracking technology has many potential surprises in store."
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Dr. A
on Thu 05 Jan 2012 10:42 PM CST
Employees keep their distance from the abusive boss
Confronting an abusive boss is easier said than done: employees coping with the stress of abusive treatment prefer to avoid direct communication even though it would be the most effective tactic in terms of emotional well-being. This has been shown in a new study from the University of Haifa, published in the International Journal of Stress Management (American Psychological Association). "Abusive supervision is highly distressing for employees. Our study shows that the strategies being used by employees to cope with the stress caused by such behavior do not lead to the most positive outcomes," said Prof. Dana Yagil, who headed the study. Earlier studies have examined the effect of abusive supervision on employee performance, but the new study set out to determine the effect of the different coping strategies on employee well-being. The study, which Prof. Yagil conducted with Prof. Hasida Ben-Zur and Inbal Tamir, of the University of Haifa's Faculty of Social Welfare and Health Sciences, examined five types of strategies used for coping with the stress factor of abusive treatment: directly communicating with the abusive supervisor to discuss the problems; using forms of ingratiation – i.e., doing favors, using flattery and compliance; seeking support from others; avoiding contact with the supervisor; and what is known as "reframing" – mentally restructuring the abuse in a way that decreases its threat. Participating in the study were 300 employees who were asked to rate the frequency of experiencing abusive behavior by a supervisor, such as ridicule, invasion of privacy, rudeness and lying. The participants were also asked to rate the frequency of engaging in each of 25 strategies that belong to the five categories. For example: "I tell the supervisor directly that he/she must not treat me like that" (direct communication category) ; "I support the supervisor in matters that are important to him/her, so that he/she will see I am on his/her side" (ingratiation); "I try to have the least possible contact with the supervisor (avoidance of contact); "I relieve myself by talking to other people about the supervisor's behavior" (support-seeking); and "I remind myself that there are more important matters in my life" (reframing). The study found that abusive treatment from a superior was most strongly associated with avoiding contact – disengaging from the supervisor as much as possible and to seeking social support. Abusive supervision was least strongly associated with the strategy of direct communication. However, avoidance and seeking support resulted in the employees' experiencing negative emotions, while communication with the supervisor – which employees do less - was the strategy most strongly related to employees' positive emotions. "It is understandable that employees wish to reduce their contact with an abusive boss to a minimum," says Dr. Yagil. "However, this strategy further increases the employee's stress because it is associated with a sense of weakness and perpetuates their fear of the supervisor." The study shows that managers should be alert to signs of employee detachment - as it might indicate that their own behavior is being considered offensive by those employees. Wednesday, January 4
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Dr. A
on Wed 04 Jan 2012 07:08 AM CST
In a study that investigates the challenges of disseminating clinical research findings in peer-reviewed biomedical journals, Yale School of Medicine researchers have found that fewer than half of a sample of trials primarily or partially funded by the National Institutes of Health (NIH) were published within 30 months of completing the clinical trial. These findings appear in the January issue of the British Medical Journal, which focuses on the topic of unpublished evidence.
"When research findings are not disseminated, the scientific process is disrupted and leads to redundant efforts and misconceptions about clinical evidence," said Joseph Ross, M.D., first author of the study and a Yale assistant professor of medicine. "Such inaction undermines both the trial in question and the evidence available in peer-reviewed medical literature. This has far-reaching implications for policy decisions, and even institutional review board assessments of risks and benefits associated with future research studies." Ross and co-authors performed a cross-sectional analysis of NIH-funded clinical trials registered within ClinicalTrials.gov, a trial registry and results database maintained by the U.S. National Library of Medicine. All trials in the study sample were registered after September 30, 2005 and completed by December 31, 2008, allowing at least 30 months for publication following completion of the trial. They found that overall fewer than half of NIH-funded trials in the sample were published in a peer-reviewed, MEDLINE-indexed biomedical journal within 30 months of trial completion. They also found that one-third of trials remained unpublished 51 months after completion. Ross said that there may be many reasons for lack of publication, such as not getting accepted by a journal or not prioritizing the dissemination of research findings. Still, he said, there are alternative methods for providing timely public access to study results, including the results database at ClinicalTrials.gov that was created in response to Federal law. "Steps must be taken to ensure the timely dissemination of publicly funded research so that data from all those who volunteer are available to inform future research and practice," Ross said. While this study was focused on trials funded by NIH, Ross said that similar problems with non-publication and delayed publication of research findings have been described among trials funded by the pharmaceutical and medical device industries, as well as by non-profit organizations. "This suggests that the current culture of research needs to prioritize the timely public dissemination of research findings, ideally via peer-reviewed journals, for research funded by both public and private sources," said Ross. "More work needs to be done to better understand impediments to publication." |
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