Men at Higher Risk for Mild Memory Loss Than Women

ST. PAUL, Minn. – Men may be at higher risk of experiencing mild cognitive impairment (MCI), or the stage of mild memory loss that occurs between normal aging and dementia, than women, according to a study published in the January 25, 2012, online issue of Neurology®, the medical journal of the American Academy of Neurology.

“These results are surprising, given that women generally have higher rates of dementia than men,” said study author R.O. (Rosebud) Roberts, MB ChB, MS, of the Mayo Clinic in Rochester, Minn., and a member of the American Academy of Neurology. “The risk of MCI in men and women combined was high in this age group of elderly persons. This is disturbing given that people are living longer, and MCI may have a large impact on health care costs if increased efforts at prevention are not used to reduce the risk.”

For the study, a group of 1,450 people from Olmsted County, Minn., between the ages of 70 and 89 and free of dementia at enrollment underwent memory testing every 15 months for an average of three years. Participants were also interviewed about their memory by medical professionals. By the end of the study period, 296 people had developed MCI.

The study found that the number of new cases of MCI per year was higher in men, at 72 per 1,000 people compared to 57 per 1,000 people in women and 64 per 1,000 people in men and women combined. MCI with memory loss present was more common at 38 per 1,000 people than MCI where memory loss was not present, which affected 15 per 1,000 people. Those who had less education or were not married also had higher rates of MCI.

“Our study suggests that risk factors for mild cognitive impairment should be studied separately in men and women,” said Roberts.

Another finding of interest in the study showed that among people who were newly diagnosed with MCI, 12 percent per year were later diagnosed at least once with no MCI, or reverted back to what was considered “cognitively normal.” Roberts said the majority of people with MCI, about 88 percent per year, continue to have MCI or progress to dementia.

The study was supported by the National Institutes of Health, the Robert Wood Johnson Foundation, the Robert H. and Clarice Smith and Abigail van Buren Alzheimer’s Disease Research Program and was made possible by the Rochester Epidemiology Project.

The American Academy of Neurology, an association of 24,000 neurologists and neuroscience professionals, is dedicated to promoting the highest quality patient-centered neurologic care. A neurologist is a doctor with specialized training in diagnosing, treating and managing disorders of the brain and nervous system such as Alzheimer’s disease, stroke, migraine, multiple sclerosis, brain injury, Parkinson’s disease and epilepsy.

Released: 1/17/2012

Source: American Academy of Neurology

Related Link:

http://www.newswise.com/articles/study-men-at-higher-risk-for-mild-memory-loss-than-women

‘Dabbling’ in Hard Drugs in Middle Age Linked to Increased Risk of Death

Newswise — Young adults often experiment with hard drugs, such as cocaine, amphetamines and opiates, and all but about 10 percent stop as they assume adult roles and responsibilities. Those still using hard drugs into their 50s are five times more likely to die earlier than those who do not, according to a new study by University of Alabama at Birmingham researchers published online Jan. 27, 2012, in the Journal of General Internal Medicine.

According to the National Survey on Drug Use and Health, 9.4 percent of Americans ages 50-59 and 7 percent of adults ages 35-49 reported use of a drug other than marijuana sometime in the past year. The study’s lead author, Stefan Kertesz, M.D., associate professor in the UAB Division of Preventive Medicine. and colleagues attempted to discover if lifelong hard-drug use shortens lifespan to better enable primary-care doctors to advise patients who use drugs recreationally.

“While government guidelines have not endorsed screening for drugs in primary care, many doctors are challenged when they discover patients continue to dabble with them,” Kertesz says. “In primary-care practice, we often hear from stable patients who report using some cocaine, irregularly, perhaps on weekends. It’s an underappreciated but very common situation. The typical question physicians have to ask is ‘If this patient doesn’t have addiction, what advice can I give other than noting that it’s unwise to break the law?’ After all, we are supposed to be doctors, not law enforcement.”

Kertesz and a research team from other universities looked at data from the Coronary Artery Risk Development in Young Adults Study for their analysis. 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 ages 18-30 were recruited and followed from 1985 to 2006.

The research team looked specifically at the reported use of “hard drugs” by 4,301 of the CARDIA participants. They compared people who stopped drug use early to those who continued and calculated the likelihood of premature death among these groups.

“Fourteen percent of the people in the study reported recent hard-drug use at least once, and of these, half continued using well into middle age,” Kertesz says. “But, most of the drug users in our study were not addicts. They were dabblers who used just a few days a month.”

Kertesz and his colleagues found that older hard-drug users were more likely to report being raised in economically challenged circumstances in a family that was unsupportive, abusive or neglectful. The team also found that those who were heavy drug users into young adulthood and continued at lower levels into middle age were roughly five times more likely to die than persons who didn’t use drugs.

“We can’t assume that drugs caused death, as in an overdose,” he says. “Rather what we found is that middle-age adults who continue to dabble in hard drugs represent a group that is at risk of bad outcomes — which could include death from trauma, heart disease or other causes that are not a direct result of their drug use — at a higher rate than people who stopped using drugs.”

Kertesz added that the team’s findings are a reminder that people who continue to use drugs are potentially quite vulnerable. They often have grown up under economic and psychosocial stress from childhood onward. They continue to smoke and drink and they remain at elevated risk of premature death.

“Based on the data we hope to offer better advice to primary-care doctors struggling with the rising tide of drug-taking by adults who have not left behind many of the bad habits they learned in young adulthood,” he says.

Study co-authors include Yulia Khodneva, M.D., Monika Safford, M.D., and Joseph Schumacher, Ph.D., UAB Division of Preventive Medicine; Jalie Tucker, Ph.D., UAB School of Public Health; Joshua Richman, M.D., Ph.D., UAB Department of Surgery; Bobby Jones, Ph. D., Department of Statistics, Carnegie Mellon University; and Mark J. Pletcher, M.D., departments of Epidemiology & Biostatistics and Medicine, University of California, San Francisco.

Released: 1/27/2012

Source: University of Alabama at Birmingham

Related Link:

http://newswise.com/articles/dabbling-in-hard-drugs-in-middle-age-linked-to-increased-risk-of-death

CT Scans for Dizziness in the ER: Worth the Cost?

Newswise — DETROIT – Performing CT scans in the emergency department for patients experiencing dizziness may not be worth the expense – an important finding from Henry Ford Hospital researchers as hospitals across the country look for ways to cut costs without sacrificing patient care.

According to the Henry Ford study, less than 1 percent of the CT scans performed in the emergency department revealed a more serious underlying cause for dizziness – intracranial bleeding or stroke – that required intervention.

The findings suggest that it may be more cost effective for hospitals to instead implement stricter guidelines for ordering in-emergency department CT scans of the brain and head for patients experiencing dizziness.

“When a patient comes into the emergency department experiencing dizziness, a physician’s first line of defense is often to order a CT scan to rule out more serious medical conditions. But in our experience it is extremely rare that brain and head imagining yields significant results,” says study author Syed F. Ahsan, M.D., a neuro-otologist in the Department of Otolaryngology-Head & Neck Surgery at Henry Ford.

“It is our hope that our investigation into our own practices will shed light on avenues to run leaner practices within our institution, as well as serve as a model for other health systems.”

The study will be presented Jan. 26 in Miami Beach at the annual Triological Society’s Combined Sections Meeting.

The Henry Ford study was a retrospective review of 1,681 patients with dizziness or vertigo who came into a Detroit metropolitan emergency department between January 2008 and January 2011.

Of those patients, nearly half (810 patients) received a CT scan of the brain and head, but only 0.74 percent of those scans yielded clinically significant results that required intervention. In all, the total cost for the CT scans during the three-year period was $988,200.

The analysis also revealed that older patients and those with a lower income were more likely to receive a CT scan for dizziness when they came into the emergency department.

While dizziness may signal intracranial bleeding or stroke, it is more likely that the cause is due to dehydration, anemia, a drop in blood pressure with standing (orthostatic hypotension), problems or inflammation in the inner ear such as benign paroxysmal postional vertigo, labyrinthitis or meniere’s disease, or vestibular neuritis.

And, Dr. Ahsan notes, in previous studies it has been well documented that CT scans are not very effective in detecting stroke or intracranial bleeding in the acute (emergency room) setting.

Ultimately, the study shows that there is potential for cost savings by creating and implementing stronger guidelines to determine when it is medically necessary for patients with dizziness to undergo CT imaging in the emergency department.

Funding: Henry Ford Hospital

Along with Dr. Ahsan, Henry Ford study co-authors are Mausumi N. Syamal, M.D., and Kathleen Yaremchuk, M.D.

Released:  1/26/2012

Source: Henry Ford Health System

Related Link:

http://www.newswise.com/articles/ct-scans-for-dizziness-in-the-er-worth-the-cost

To Turn Up the Heat in Chilies, Just Add Water!

Newswise — Biologists have learned in recent years that wild chilies develop their trademark pungency, or heat, as a defense against a fungus that could destroy their seeds. But that doesn’t explain why some chilies are hot and others are not.

New research provides an answer: Hot chilies growing in dry areas need more water to produce as many seeds as non-pungent plants, but the Fusarium fungus is less of a threat in dryer environments so chilies in those areas are less likely to turn up the heat. In wetter regions, where Fusarium thrives, wild chilies build up their reserves of spicy capsaicin in self-defense.

“Despite the reduced benefit of pungency in dry environments, hot plants still occur there, as does the deadly fungus. That suggests that the greater presence of non-pungent plants that produce substantially more seeds is the result of a fitness-based tradeoff,” said David Haak, lead author of a paper describing the research published Wednesday (Dec. 21) inProceedings of the Royal Society B. The Royal Society is the United Kingdom’s academy of science.

Haak, a post-doctoral researcher at Indiana University, conducted the research as part of his doctoral work at the University of Washington. Co-authors of the paper are Leslie McGinnis of the University of Michigan, who did the work while a UW undergraduate; Douglas Levey of the University of Florida and Joshua Tewksbury, a UW biology professor who leads the research group.

The scientists examined pungency differences by comparing the proportion of pungent plants with that of non-pungent plants in 12 populations of wild chilies in southeastern Bolivia along a 185-mile line that gradually progressed from a relatively dry region to a wetter region. They conducted plant censuses in focal populations five times between 2002 and 2009, and tagged plants in each census so they could determine new seedlings the next time.

They found that, starting in the dryer northeast part of the section, 15 to 20 percent of the plants had pungent fruit, and pungency increased along the line toward the wetter southwest, where they never found a single plant that did not produce pungent fruit.

They also selected three populations of chili plants that each produced both pungent and non-pungent fruit and spanned the range of rainfall and pungency differences. They then grew seeds from those plants in the UW Botany Greenhouse to examine what affect water availability had on pungency.

The 330 plants that resulted from those seeds were grown under identical conditions until they reached their first flowering, then were separated into two groups – one that received plenty of water and one that was stressed by receiving only the amount of water available to plants in the driest area of Bolivia from which seeds were taken.

The scientists found that under water-stressed conditions, non-pungent plants produced twice as many seeds as pungent plants. That suggests the pungent plants trade some level of fitness for protection from the Fusarium fungus, Haak said.

The researchers determined the pungent plants have developed a reduced efficiency in water use, so in dryer areas they produce fewer seeds and are more limited in reproduction. In wetter areas, non-pungent plants are at a reproductive disadvantage because they are much more likely to have their seeds attacked by the fungus.

“It surprised us to find that the tradeoff to produce capsaicin in pungent plants would involve this major physiological process of water-use efficiency,” Haak said.

He noted that over the entire range, 90 to 95 percent of the chili fruits had some level of fungal infection, and pungent plants were better able to defend themselves.

The research was funded by grants from the National Science Foundation; the National Geographic Society; Sigma Xi, the scientific research society; and the UW Department of Biology.

Released: 12/20/2011

Source: University of Washington

Related Link:

http://www.newswise.com/articles/to-turn-up-the-heat-in-chilies-just-add-water

New Findings…Group Settings Can Diminish Expressions of Intelligence

Research led by scientists at the Virginia Tech Carilion Research Institute found that small-group dynamics — such as jury deliberations, collective bargaining sessions, and cocktail parties — can alter the expression of IQ in some susceptible people. “You may joke about how committee meetings make you feel brain dead, but our findings suggest that they may make you act brain dead as well,” said Read Montague, director of the Human Neuroimaging Laboratory and Computational Psychiatry Unit at the Virginia Tech Carilion Research Institute, who led the study.

The scientists used functional magnetic resonance imaging (fMRI) to investigate how the brain processes information about social status in small groups and how perceptions of that status affect expressions of cognitive capacity.

“We started with individuals who were matched for their IQ,” said Montague. “Yet when we placed them in small groups, ranked their performance on cognitive tasks against their peers, and broadcast those rankings to them, we saw dramatic drops in the ability of some study subjects to solve problems. The social feedback had a significant effect.”

“Our study highlights the unexpected and dramatic consequences even subtle social signals in group settings may have on individual cognitive functioning,” said lead author Kenneth Kishida, a research scientist with the Virginia Tech Carilion Research Institute. “And, through neuroimaging, we were able to document the very strong neural responses that those social cues can elicit.”

The researchers recruited subjects from two universities and administered a standard test to establish baseline IQ. The results were not viewed until after a series of ranked group IQ tasks, during which test takers, in groups of five, received information about how their performances compared to those of the other group members.

Although the test subjects had similar baseline IQ scores — a mean of 126, compared to the national average of 100 — they showed a range of test performance results after the ranked group IQ tasks, revealing that some individuals’ expressed IQ was affected by signals about their status within a small group.

The researchers wanted to know what was happening in the brain during the observed changes in IQ expression. The subjects were divided into two groups based on the results of their final rank — the high performers, who scored above the median, and the low performers, who scored at or below the median. Two of every group of five subjects had their brains scanned using fMRI while they participated in the task.

Among the researchers’ findings:

1. Dynamic responses occurred in multiple brain regions, especially the amygdala, the prefrontal cortex, and the nucleus accumbens — regions believed to be involved in emotional processing, problem solving, and reward and pleasure, respectively.

2. All subjects had an initial increase in amygdala activation and diminished activity in the prefrontal cortex, both of which corresponded with a lower problem-solving ability.

3. By the end of the task, the high-performing group showed a decreased amygdala activation and an increased prefrontal cortex activation, both of which were associated with an increased ability to solve more difficult problems.

4. Positive changes in rank were associated with greater activity in the bilateral nucleus accumbens, which has traditionally been linked to learning and has been shown to respond to rewards and pleasure.

5. Negative changes in rank corresponded with greater activity in the dorsal anterior cingulate cortex, consistent with a response to conflicting information.

6. Neither age nor ethnicity showed a significant correlation with performance or brain responses. A significant pattern did emerge along gender lines, however. Although male and female participants had the same baseline IQ, significantly fewer women (3 of 13) were in the high-performing group and significantly more (10 of 13) fell into the low-performing group.

“We don’t know how much these effects are present in real-world settings,” Kishida said. “But given the potentially harmful effects of social-status assignments and the correlation with specific neural signals, future research should be devoted to what, exactly, society is selecting for in competitive learning and workplace environments. By placing an emphasis on competition, for example, are we missing a large segment of the talent pool? Further brain imaging research may also offer avenues for developing strategies for people who are susceptible to these kinds of social pressures.”

“This study tells us the idea that IQ is something we can reliably measure in isolation without considering how it interacts with social context is essentially flawed,” said coauthor Steven Quartz, a professor of philosophy in the Social Cognitive Neuroscience Laboratory of Caltech. “Furthermore, this suggests that the idea of a division between social and cognitive processing in the brain is really pretty artificial. The two deeply interact with each other.”

“So much of our society is organized around small-group interactions,” said Kishida. “Understanding how our brains respond to dynamic social interactions is an important area of future research. We need to remember that social dynamics affect not just educational and workplace environments, but also national and international policy-making bodies, such as the U.S. Congress and the United Nations.”

The research appears in the Jan. 23, 2012 issue of the journalPhilosophical Transactions of the Royal Society B in the article, “Implicit signals in small group settings and their impact on the expression of cognitive capacity and associated brain responses,” by Kenneth Kishida; Dongni Yang, a former postdoctoral researcher in the Department of Neuroscience at Baylor College of Medicine; Karen Hunter Quartz, a director of research in the Graduate School of Education and Information Studies of the University of California, Los Angeles; Steven Quartz; and Read Montague, corresponding author, who is also a professor of physics at Virginia Tech. The research was supported by grants from the Wellcome Trust and the Kane Family Foundation to Montague and the National Institutes of Health to Montague and Kishida. The article is online athttp://rstb.royalsocietypublishing.org/content/367/1589/704.abstract?sid=5fc88e56-8a71-4a9b-be8d-ad3fa88c631e

Released: January 22, 2012

Source: Virginia Tech (Virginia Polytechnic Institute and State University)

Related Link:

http://www.newswise.com/articles/group-settings-can-diminish-expressions-of-intelligence

Cohabitating Valentines Are Happier Than Wedded Couples

Newswise — ITHACA, N.Y. — When it comes to the well-being of married versus cohabitating Valentines, wedded couples experience few advantages in psychological well-being and social ties, according to a new study at Cornell University.

The study, “Reexamining the Case for Marriage: Union Formation and Changes in Well-being,” is being published in the February issue of the Journal of Marriage and Family(available online: http://bit.ly/xL4t9U).

“We found that differences between marriage and cohabitation tend to be small and dissipate after a honeymoon period. Also while married couples experienced health gains – likely linked to the formal benefits of marriage such as shared health care plans – cohabiting couples experienced greater gains in happiness and self-esteem. For some, cohabitation may come with fewer unwanted obligations than marriage and allow for more flexibility, autonomy and personal growth,” said Kelly Musick, associate professor of policy analysis and management at Cornell’s College of Human Ecology, who co-authored the study with sociologist Larry Bumpass of the University of Wisconsin-Madison.

“Marriage has long been an important social institution, but in recent decades western societies have experienced increases in cohabitation, before or instead of marriage, and increases in children born outside of marriage,” said Musick. “These changes have blurred the boundaries of marriage, leading to questions about what difference marriage makes in comparison to alternatives.”

Previous research has sought to prove a link between marriage and well-being, but many studies compared marriage to being single, or compared marriages and cohabitations at a single point in time.

This study compares marriage to cohabitation while using a fixed-effects approach that focuses on what changes occur when single men and women move into marriage or cohabitation and the extent to which any effects of marriage and cohabitation persist over time.

The researchers used a sample from the National Survey of Families and Households of 2,737 single men and women, 896 of whom married or moved in with a partner over the course of six years. The study focused on key areas of well-being, considering questions on happiness, levels of depression, health and social ties.

“Compared to most industrial countries, America continues to value marriage above other family forms,” concluded Musick. “However our research shows that marriage is by no means unique in promoting well-being and that other forms of romantic relationships can provide many of the same benefits.”

The study was funded in part by the National Institute of Child Health and Human Development and the Office of Behavioral and Social Sciences.

Released: 1/24/2012

Source:  Cornell University

Related Link:

http://newswise.com/articles/cohabitating-valentines-are-happier-than-wedded-couples-finds-study

Museum to Visitors: Please Do Touch, for Scientific Purposes

Photo Credit: The Walters Art Museum, Modest Venus, or Venus Pudica, a 10.5-inch bronze statuette cast around 1500 by an anonymous Italian artist, is one of the pieces replicated for museum goers to caress for science at an exhibition in Baltimore.

Newswise — It’s the first rule at any art museum: Do not touch the artifacts. Except at this museum and at this one time.

At the “Touch and the Enjoyment of Sculpture: Exploring the Appeal of Renaissance Statuettes” exhibition — at the Walters Art Museum in Baltimore through April 15 — visitors are invited to disregard that decree and to hold, stroke and even caress the pieces.

In fact, handling the objects d’arts — replicas of famous 16th century statuettes held by the Walters — is one of the reasons for the exhibition, explains neuroscientist Steven Hsiao, a researcher at the Johns Hopkins Brain Science Institute. The institute is partnering with the Walters on the show, the fourth in a series of projects between the museum and Johns Hopkins.

“We’re challenging people to think about why physical contact with works of art can be so satisfying,” says Hsiao, whose work includes exploring many aspects of humans’ sense of touch. “In fact, as people browse the exhibition, we will be asking them to react to what they are seeing and feeling.”

The installation incorporates 12 works of art from the Walters collection, along with 22 replicas for visitors to touch and rate, providing data for ongoing research.

The project melds the research interests of Hsiao, who specializes in many facets of touch, and those of Joaneath Spicer, the Walters’ curator of Renaissance and Baroque art, who studies the Renaissance penchant for collecting and commissioning small statuettes and other luxury goods that were satisfying to touch and handle.

But the special appeal of this exhibition lies in the opportunity to join in comparative experiments with the statuettes (well, the replicas, actually).

“We’ll be asking visitors to handle them and to tell us what sculptures they prefer and to rate how they like sculptures that have been modified in their shape and texture. This exhibition allows us to dissect why some objects feel better than others” Hsiao says.

Visitors will register these preferences, and other reactions, on Apple iPads, and visitors will be able to see a dynamic display of their responses. The data will be used in Hsaio’s and Spicer’s research on tactile aesthetics. (Visitors will not be handling the original 16th century artwork; they will only be permitted to touch replica art exclusively fashioned for the show.)

The Walters Art Museum is open from 10 a.m. to 5 p.m. Wednesdays through Sundays and is located at 600 North Charles St. in Baltimore.

Related links:
Steven Hsiao:
http://neuroscience.jhu.edu/StevenHsiao.php

The Johns Hopkins Brain Science Institute:
http://www.hopkinsmedicine.org/brainscience/

The Walters Art Museum:
http://thewalters.org/eventscalendar/eventdetails.aspx?e=2207

Released: Released: 1/23/20

Source: Johns Hopkins

Related Link:

http://newswise.com/articles/museum-to-visitors-please-do-touch-for-scientific-purposes

Sleep Preserves and Enhances Bad Emotional Memories

Photo Credit: UMass Amherst, Based on a recent study that included polysomnography, neuroscientists at UMass Amherst suggest that emotional memories are protected by the brain during sleep.

Newswise — AMHERST, Mass. – A recent study by sleep researchers at the University of Massachusetts Amherst is the first to suggest that a person’s emotional response after witnessing an unsettling picture or traumatic event is greatly reduced if the person stays awake afterward, and that sleep strongly “protects” the negative emotional response. Further, if the unsettling picture is viewed again or a flashback memory occurs, it will be just as upsetting as the first time for those who have slept after viewing compared to those who have not.

UMass Amherst neuroscientists Rebecca Spencer, Bengi Baran and colleagues say this response could make sense from an evolutionary point of view, because it would provide survival value to our ancestors by preserving very negative emotions and memories of life-threatening situations and offer a strong incentive to avoid similar occasions in the future.

“Today, our findings have significance for people with post-traumatic stress disorder, for example, or those asked to give eye-witness testimony in court cases,” Spencer says.

“We found that if you see something disturbing, let’s say an accident scene, and then you have a flashback or you’re asked to look at a picture of the same scene later, your emotional response is greatly reduced, that is you’ll find the scene far less upsetting, if you stayed awake after the original event than if you slept. It’s interesting to note that it is common to be sleep-deprived after witnessing a traumatic scene, almost as if your brain doesn’t want to sleep on it.” The study is reported in the current issue of the Journal of Neuroscience.

In their experiments involving 68 healthy female and 38 male (total 106) young adults between 18 and 30 years old, Spencer and colleagues set out to explore, among other ideas, an assumption that the well-known enhancement of memory that occurs during sleep is tied to a change in emotional response to the memory.

Further, in a subset of subjects the neuroscientists used a polysomnograph with electrodes attached to subjects’ scalps as they slept, to investigate whether dreaming or other brain processes that occur during rapid-eye-movement (REM) sleep periods may play a role in the processing of emotions.

In the two-phase experiment, participants were shown pictures on a computer screen and asked to rate each one as sad or happy as well as their own response as calm or excited to each, on a scale of 1-9. The researchers counted sad-happy ratings and calm-excited of 1-3 as negative images and 4-6 as neutral, so each participant’s overall “emotional value” score was unique.

Twelve hours later, participants were shown a mix of new and already viewed pictures and asked whether they had ever seen the picture before and to rate each again on the two scales. They all kept a sleep diary and took a sleep quality index test, as well.

Session timing was arranged so that 82 subjects were assigned either to a Sleep group who saw the first set of pictures late in the day and the second group of pictures after they had slept overnight or to a Wake group, who saw the first set of pictures in the morning and the second set later the same day. To rule out a possible circadian effect on attention, 24 different subjects followed the same routine but with only a 45-minute break between the two phases. Polysomnography data were collected from 25 participants in the Sleep group in their own homes overnight.

Spencer and colleagues found that sleep had significant effects on participants’ memories and feelings. Recognition memory for the pictures was better following sleep compared with wake.

Importantly, the researchers found that contrary to previous assumptions that sleep might soften negative emotional effects of a disturbing event, a period of sleep was associated with participants’ maintaining the strength of their initial negative feelings compared to a period of wakefulness. This suggests that sleep’s effect on memory and emotion are independent, the authors state.

The researchers found no significant relationship between REM sleep time and participants’ accuracy in recalling whether they had seen a picture in both the first and second phases of the study. As such, how sleep protects the emotional response and the emotional memory are unanswered questions. “Sleep may, in fact, be protective of the emotional salience of a stimulus just as sleep protects the emotional memory,” the authors point out.

This work was supported by the National Institutes of Health and the UMass Amherst Commonwealth Honors College.

Released: 1/16/2012

Source:  University of Massachusetts Amherst

Related Link:

http://www.newswise.com/articles/sleep-preserves-and-enhances-bad-emotional-memories

In Hot Water: Ice Age Findings Forecast Problems

The first comprehensive study of changes in the oxygenation of oceans at the end of the last Ice Age (between about 10 to 20,000 years ago) has implications for the future of our oceans under global warming. The study, which was co-authored by Eric Galbraith, of McGill’s Department of Earth & Planetary Sciences, looked at marine sediment and found that that the dissolved oxygen concentrations in large parts of the oceans changed dramatically during the relatively slow natural climate changes at the end of the last Ice Age. This was at a time when the temperature of surface water around the globe increased by approximately 2 °C over a period of 10,000 years. A similar rise in temperature will result from human emissions of heat-trapping gases within the next 100 years, if emissions are not curbed, giving cause for concern.

Most of the animals living in the ocean, from herring to tuna, shrimp to zooplankton, rely on dissolved oxygen to breathe. The amount of oxygen that seawater can soak up from the atmosphere depends on the water temperature at the sea surface. As temperatures at the surface increase, the dissolved oxygen supply below the surface gets used up more quickly. Currently, in about 15 per cent of the oceans – in areas referred to as dead zones – dissolved oxygen concentrations are so low that fish have a hard time breathing at all. The findings from the study show that these dead zones increased significantly at the end of the last Ice Age.

“Given how complex the ocean is, it’s been hard to predict how climate change will alter the amount of dissolved oxygen in water. As a result of this research, we can now say unequivocally that the oxygen content of the ocean is sensitive to climate change, confirming the general cause for concern.”

This research was funded by the Natural Sciences and Engineering Research Council of Canada (NSERC) and the Canadian Institute for Advanced Research (CIFAR).

The results of this study were published in Nature Geoscience

Via Newswise

Released: 1/17/2012

Source: McGill University

Related Link:

http://www.newswise.com/articles/in-hot-water-ice-age-findings-forecast-problems

Researchers Find Powerful People Think They Are Taller Than They Really Are

Napoleon Bonaparte, the notoriously “short” French emperor, may have stood only 5 feet 6, but being a powerful military and political leader probably made him feel much taller, suggests a new study by an organizational behavior expert at Washington University in St. Louis.

Newswise — Napoleon Bonaparte, the notoriously “short” French emperor, may have stood only 5 feet 6, but being a powerful military and political leader probably made him feel much taller, suggests a new study by an organizational behavior expert at Washington University in St. Louis.

“Although a great deal of research has shown that more physically imposing individuals are more likely to acquire power, this work is the first to show that powerful people feel taller than they are,” says Michelle M. Duguid, PhD, assistant professor of organizational behavior at Olin Business School.

Duguid is co-author, with Jack Concalo, PhD, of Cornell University, of “Living Large: The Powerful Overestimate Their Own Height,” published in the current issue of the journalPsychological Science.

In a series of three experiments, the researchers found a definite correlation between feeling powerful and feeling tall, and even suggest that future research may want to examine whether employers should consider placing short high-ranking workers in higher offices to raise their psychological sense of power.

“Height is often used as a metaphor for power,” Duguid says. “Powerful people ‘feel like the big man on campus,’ and people ‘look up to them.’ We find that the psychological experience of power may cause individuals to feel taller than objective measurement indicates they really are.”

In the researcher’s first experiment, some participants were asked to recall an incident in which they had power over another individual while others were asked to recall an incident in which someone else had power over them.

They were then asked to estimate their size in relation to a pole that had been set precisely 20 inches taller than their actual heights.

Those who had been conditioned to feel ‘empowered’ thought the pole was nearer in height to them than those who’d been made to feel subordinate.

In the second experiment, two pairs of volunteers were asked to role play a scenario in which one was a manager and the other an ordinary worker.

They were then asked to give their exact heights in a questionnaire, with those having played the role of manager supplying exaggerated figures.

Finally, the participants were conditioned in the same way as they were in the first experiment, and then asked to choose an avatar in a second-life game that they thought best represented them. The more empowered volunteers consistently chose taller avatars.

“These findings may be a starting point for exploring the reciprocal relationship between the psychological and physical experiences of power,” Duguid says. “An interesting direction for future research would be to determine whether associations between power and size extend to other self-perceptions and self-categorization.”

Released: 1/17/2012

Source: Washington University in St. Louis

Related Link:

http://www.newswise.com/articles/powerful-people-think-they-are-taller-than-they-really-are