Kudzu

Written by Science Knowledge on 8:00 AM

Kudzu (Pueraria lobata or P. montana) is a vine that is part of the pea family, Fabaceae, introduced to the United States from Asia in the late 1800s. Farmers in the southeastern states planted the vine because of its fast growth with a plan to reduce soil erosion and possibly use it as animal feed. The vine also belongs to the legume family, which includes plants that capture nitrogen at the plant root and make it available for the plant’s use; this process is called nitrogen fixation. Kudzu, however, does not control erosion. Instead it bursts into growth so prolific that it engulfs every stationary thing in its path. Those early farmers probably soon discovered that without constant cutting, the vine overgrew yards, gardens, trees, orchards, stream banks, hillsides, and even abandoned houses and farm equipment. In 2005 Georgia farmer Jason Millsaps told National Geographic, “I’ve measured a foot a day [of kudzu growth]. It’s a never-ending battle to keep it back.” Kudzu remains a very big problem in U.S. agriculture, and universities have set up project teams to work solely on the task of solving the kudzu problem.

Source of Information : Green Technology Conservation Protecting Our Plant Resources
Kudzu is one example of an aggressive invasive plant, nonnative to the United States. The vine has spread from its origins to the rest of the southeastern states, from Florida north to Maryland and west to Texas. Some farmers have nicknamed it “the vine that ate the South.” At the current rate of global warming, scientists predict kudzu will spread to Michigan in about 30 years. The University of Arkansas agricultural research station offers on its Web site the following: “The joke goes that you should fertilize kudzu in a dry year with motor oil because lubricating the undersides of the leaves reduces the chance of sparks as it races across the ground.” This fast growth explains why many invasive plants threaten the surroundings they enter; nature simply cannot adapt fast enough to repel them.

Aggressive plants may be the most harmful of all invasive species because they disrupt the foundation of ecosystems. Aggressive invaders kill or dislodge native photosynthetic plants that support a community of herbivores, carnivores, and predators in addition to microbes and invertebrates Kudzu also blocks sunlight from reaching soil organisms, overwhelms tree trunks and leaves, and can literally choke any woodland it overruns.

Kudzu removal is difficult for the following five reasons: (1) it creates deep and extensive root systems; (2) it grows back within days of cutting; (3) kudzu has no natural enemies outside Asia; (4) its seeds disperse easily, carried by wind, water, and animals; and (5) the herbicides active against kudzu also kill many native plants. Entomologist David Orr of North Carolina State University told the New York Times in 1998, “It takes a 55-gallon drum of herbicide to kill just one acre, and even then you don’t really kill it.” Protection against kudzu invasion may require a combination of new technologies and a certain amount of cleverness.

New techniques meant to save pristine forests from kudzu attack may soon employ caterpillars called soybean loopers, which have been engineered in laboratories to devour kudzu leaves as they do soybean plants. Though this research has been conducted since the mid-1990s, research has yet to find the right approach for looper-destruction of the thousands of square miles of kudzu infestation. Another approach under study involves a fungus named Colletotrichum gloeosporioides, which causes a deadly infection in kudzu after the fungus has been grown and strengthened in a laboratory. These and other biological means of fighting kudzu must come onto the scene quickly in order to help agriculture threatened by invasion.

Meanwhile, research into kudzu’s valuable properties has taken shape. Perhaps kudzu can be made into a food source or serve as a sustainable answer to deforestation. Botanists have explored kudzu’s use in pulp and papermaking, for example. University of Toronto botanist Rowan Gage told CBC News in Canada in 2007, “If you can develop it as a commodity, kudzu can pay for its own control.” Kudzu’s commercial use may be a long way off, but the fact that kudzu has caught the attention of people in Canada attests to the vine’s ability to grow and invade. Solutions from any sector of research will be helpful.

Conserving Nature’s Pharmacy

Written by Science Knowledge on 6:18 AM

The timber industry has a logical need to cut down forests in order to get the raw material it requires for making wood products. But leaving forests intact gives a different industry, the pharmaceutical industry, an opportunity to explore for new products. At least 120 different chemicals used in medicines today derive from plants or trees, especially from the jungles and rain forests of the Tropics, the very places that contain the fastest deforestation rates. Therefore, a science called ethnobotany has developed to learn more about plant-derived drugs before the plants disappear and to find ways of gathering drug producing plants in a sustainable manner.

Ethnobotany is the study of relationships between native cultures and the plant life indigenous (native) to the area where the plants live. Tropical societies have long used plant- or tree-derived medicines as part of their culture, and now some pharmaceutical companies have followed that lead and established screening programs to find as many medicinal chemicals from plants as possible, as quickly as possible. Ethnobotanists take a multifaceted approach that serves the needs of large corporations and small local communities. Ethnobotany stresses two objectives that must be met together, not separately: gaining knowledge on the traditional medicines of indigenous tribes of tropical forests and (2) conserving the forests. These two objectives set ethnobotany apart from commercial bioprospecting, in which company scientists enter the forest for the sole purpose of finding and removing useful biological products.

Ethnobotanists visit local tribes to learn their customs and methods of healing, and usually the community’s shaman, or healer, shows the study team the types of trees and plants that have produced various cures since ancient times. Some medicines come only from particular leaves, or bark, or even from insects that live only on a specific plant. Mark J. Plotkin was an early advocate of ethnobotany for the purpose of learning the medicinal practices of rain forest communities. He described for the New York Times in 1999 one of his first experiences in the forest, which turned out to be a revelation for him. On a visit to South America, Plotkin introduced himself to a shaman of the Sikiyana-Chikena tribe. Times reporter John Christensen described the meeting: “He [Plotkin] then followed the shaman into the forest and watched him pick a trailside herb, peel long strips of bark from a towering tree and drain sap from a twisted vine. Back at the village, he boiled all the ingredients together in a clay pot over a wood fire. That night, the shaman gave the thick reddish-brown liquid to a young Indian woman with a nearly fatal case of diabetes. The next morning her blood sugar level was almost normal. Within a few days she was well enough to work in her garden again.” A small number of scientists took note of the opportunities hidden in the jungle; some wished to work with local communities in a cooperative way, but undoubtedly others sought only to exploit the resources.

Plotkin has criticized bioprospecting and has urged his scientific teams to work with the local people, rather than take knowledge and chemicals to the United States without giving something back to the local community. In an interview with ActionBioscience.org, Plotkin explained, “I think the whole concept of intellectual property rights boils down to a question of good manners. If you’re going to compensate local or indigenous people, you want to do so in a culturally sensitive way. But you cannot say, ‘okay—we’ll be back in twelve years and, if we have a cure for AIDS, you’ll
be in the money.’ These people have real needs now.” Plotkin now heads the Amazon Conservation Team, which sets up medical clinics and implements apprentice programs with local tribes so they may learn forest conservation principles and computer skills.

In the long term, ethnobotanists help support the biological and cultural diversity of the places they visit. Similar conservation projects now take place all over the world, including projects in the United States with Native American tribes, who already have followed sustainable practices for generations. In addition to sharing information on health and medicine, ethnobotanists try to ensure that the end result of their studies is to support local communities and preserve their forested environment.

Source of Information : Green Technology Conservation Protecting Our Plant Resources

Marijuana Hurts Some, Helps Others

Written by Science Knowledge on 8:00 AM

Cannabis can kill or rescue neurons—children are at risk, whereas adults may benefit

Clinton didn’t inhale, Obama did— and maybe Reagan should have. New research suggests that THC, the chemical that gives marijuana its mind-bending properties, kills developing neurons, yet oddly, the same chemical saves neurons in adults with Alzheimer’s disease.

“Marijuana is not the ‘soft drug’ people like to think it is,” says neuropharmacologist
Veronica Campbell of Trinity College in Dublin, whose latest study uncovered the harmful effects of THC on young neurons. When Campbell and her co-workers treated brain cells from newborn or adolescent rats with THC, the neurons died, but THC did not have such deadly effects on neurons taken from adult rats. In fact, work from other labs shows that THC benefits adult neurons. “We don’t know why,” Campbell says. Several possibilities are being investigated for this “Jekyll and Hyde” effect.

Marijuana, like tobacco and opium, has powerful effects on the brain because certain compounds in the plant happen to have a chemical resemblance to naturally occurring substances in the body. Called endocannabinoids, these natural chemicals regulate important brain functions by controlling synapses in neural circuits that process thought and perception. According to several recent studies, these chemicals have many other functions in the brain and immune system, too—including regulating development and aiding survival of young neurons, as well as controlling the wiring of neurons into circuits for learning and memory. Smoking marijuana during the period of life when the brain is still developing obscures these critical chemical signals, Campbell suspects.

The slaughter of young neurons by THC could explain the developmental cognitive impairment seen in children born to women who smoked marijuana during pregnancy. In addition, some research on adolescent marijuana abusers shows brain damage in neural circuits that are still developing at that age.

In older brains, however, THC seems to have a protective effect. Campbell’s findings indicate that the biochemistry of neurons changes as the cells mature. The role of endocannabinoids shifts to regulate different functions—most important, assisting in the survival of aged neurons. In patients with Alzheimer’s disease, THC protects neurons from death in several ways. THC boosts depleted levels of the neurotransmitter acetylcholine, which, when diminished, contributes to the weakened mental function in Alzheimer’s patients. THC also suppresses the toxic effects of the socalled a-beta protein that may kill neurons in Alzheimer’s disease. It stimulates secretion of neuron growth by promoting substances such as brainderived neurotrophic factor, and it dampens release of the excitatory neurotransmitter glutamate, which kills neurons by overstimulation. THC and other cannabinoids also have powerful anti-inflammatory and antioxidant actions that protect neurons from immune system attack.

Despite these benefits, THC and other compounds in marijuana also have many undesirable side effects on the brain. The trick for scientists will be to isolate the active ingredients in marijuana that are beneficial and develop drugs that can be applied in the proper dose for the specific age of the patient. Campbell finds that the beneficial effects of THC are seen in much lower concentrations of the chemical than are found in the plants people use to get high. “It’s a matter of trying to balance that low concentration within a nice safety margin,” she explains. Synthetic THC-like drugs are already available, as is a naturally derived drug called Sativex that contains THC and other cannabinoids, approved in Canada for treating pain from multiple sclerosis and cancer.

In contrast to these well-controlled drugs, the weed itself is a complex witches’ brew of many brain-altering chemicals. The cannabis plant contains about 60 different cannabinoids, so the challenge lies in trying to tease out which are the important ones for protecting neurons, Campbell explains, echoing the views of other marijuana researchers. “Depending on how the plant is cultivated, the relative proportion of the different types of cannabinoids changes,” she says. “The ‘joints’ that are available now are much stronger in terms of their THC content than those that would have been around when people were thinking of cannabis as being quite a soft drug.”

Source of Information : Scientific American Mind September-October 2009

Inflammation Brings on the Blues

Written by Science Knowledge on 8:00 AM

Our immune system may mean well, but it might also cause depression

As if being stuck sick in bed wasn’t bad enough, several studies conducted during the past few years have found that the immune response to illness can cause depression. Recently scientists have pinpointed an enzyme that could be the culprit, as it is linked to both chronic inflammation— such as that found in patients with coronary heart disease, type 2 diabetes and rheumatoid arthritis—and depressive symptoms in mice.

In the new study, immunophysiologist Keith Kelley and his colleagues at the University of Illinois exposed mice to a tuberculosis vaccine that produces a low-grade, chronic inflammation. After inoculation, production in the mice brains of an enzyme called IDO, which breaks down tryptophan, spiked. The animals exhibited normal symptoms of illness such as moving around and eating less. Yet even after recovering from the physical illness induced by the vaccine, they showed signs of depression—for example, struggling less than control mice to escape from a bucket of water. Surprisingly, their listlessness was solved relatively simply. “If you block IDO, genetically or pharmaceutically, depression goes away” without interfering with the immune response, Kelley explains.

The research makes a solid case that the immune system communicates directly with the nervous system and affects important health-related behaviors such as depression. The findings could bring relief to patients afflicted with obesity, which leads to chronic inflammation, as well as to cancer patients treated with radiation and chemotherapy drugs that produce both inflammation and depression. “IDO is a new target for drug companies to aim for, to treat patients with both clinical depression and systemic inflammation,” Kelley says.

Source of Information :  Scientific American Mind September-October 2009

Underwater Suffering?

Written by Science Knowledge on 7:32 AM

A study suggests fish consciously experience discomfort

Many a seafood fan has parroted the popular idea that fish and crustaceans do not feel pain. New research, however, suggests that they may, revealing that their nervous system may be more complex than we thought—and our own awareness of pain may be much more evolutionarily ancient than suspected.

Joseph Garner of Purdue University and his colleagues in Norway report that the way goldfish respond to pain shows that these animals do experience pain consciously, rather than simply reacting with a reflex— such as when a person recoils after stepping on a tack (jerking away before he or she is aware of the sensation). In the study, the biologists found that goldfish injected with saline solution and exposed to a painful level of heat in a test tank “hovered” in one spot when placed back in their home tank. Garner labels that “fearful, avoidance behavior.” Such behavior, he says, is cognitive—not reflexive. Other fish, after receiving a morphine injection that blocked the impact of pain, showed no such fearful behavior.

Although Garner’s findings fit with previous work that tentatively suggests that fish feel pain, some experts remain unconvinced that the reaction was not an instinctive escape behavior. Still, the new study raises ethical concerns. “If we’re going to use animals in experiments, and we’re going to use animals as food, then it is really important to understand the consequences of our actions for those animals,” Garner says.

Source of Information :  Scientific American Mind September-October 2009

Indoor Air Quality

Written by Science Knowledge on 4:26 PM

If you’re like most people, when you worry about pollution, you think about the particles in the air outside. After all, that’s where cars drive, dust blows, and factories do their dirty work. But air-quality experts know the grimy truth—when it comes to air pollution, your lungs may have more to fear indoors than they do outside.

If this seems contradictory, you need to take a closer look at the environment where you spend most of your time. Items that fill many modern homes, such as carpeting, furniture, paint, and cleaning supplies, can release volatile organic compounds (VOCs). In addition, biological sources such as dander from your pets, skin flakes from your body, and spores of mold contribute to indoor air pollution. And because modern homes are surprisingly airtight, particles can build up to concentrations you’d never face outdoors. Add to this the fact that the average person spends 90 percent of the day inside, and you can see why your lungs have more to worry about from a relaxing day at home than a walk around the block.

So what can you do to improve indoor air quality and reduce your exposure to PM2.5 particles? Here are some proven techniques:

• Ventilate. Opening a window is one of the easiest ways to clear out indoor air pollutants. Even without a strong breeze, built-up pollutants will naturally spread out and drift out of an open window. Of course, this technique isn’t as useful on a hot and smoggy day, or if you live near a pollution source (say, a few feet from a heavily trafficked road). In cases like these, you might get more mileage out of an air exchanger, which brings in outside air, filters it, and uses it to heat or cool your house.

• Use exhaust fans. Stovetop cooking creates plenty of potential lung irritants, and our hot, steamy showers generate the humidity that allows mold to thrive. To cut down on these sources of indoor air pollution, make sure you have an exhaust fan in every kitchen and bathroom. Use the kitchen exhaust fan while cooking, and use the bathroom exhaust fan while cleaning and after bathing.

• Air out. Air-quality experts recommend that you air out problem items before you bring them into your house. This includes dry-cleaned clothes and new carpet, both of which release hefty quantities of VOCs. (New carpet will probably continue releasing VOCs 2 or 3 years after installation, but you can cut down on the intense initial exposure by giving it a couple of days to air out—or better yet, by going with hard floor coverings, like wood.)

One common indoor air pollutant is the residue left from cigarette smoke. Health researchers have coined the term third-hand smoke to describe the toxic particles that remain long after the visible smoke has drifted away, clinging to furniture, carpeting, upholstery, and clothing. New, but somewhat controversial, research suggests that exposure to this residue can be damaging. It’s a particular concern for young children, who are likely to crawl along particle-laden carpets.

A regular dose of fresh air keeps your indoor environment healthy. Ventilation is particularly important when you do something that releases large amounts of indoor pollutants, such as painting (even with low-VOC paints) and using strong cleaning products (like those you use to clean the bathroom, floor, oven, and so on).

Source of Information : Oreilly - Your Body Missing Manual

Confidence Wins over Smarts

Written by Science Knowledge on 1:04 AM

Speaking up counts more than competence in becoming a leader

When a group of people works to complete a task, a leader usually emerges. New research shows such leaders are not necessarily more intelligent than the other group members, but rather they simply speak up more often. Researchers at the University of California, Berkeley, gave groups of college students 45 minutes to lay the groundwork for a business and then asked the students to rate one another on intelligence, judgment and other traits. The students believed that the people who spoke more often were the smartest in each group—even when, during another group exercise involving math problems, they offered more incorrect answers than did others who were less talkative. Those who did not say much were judged as averagely intelligent and not so creative. A later look at the participants’ SAT scores revealed that, on average, the leaders had the same scores as the rest of the group. “The main reason dominant people took charge is they jumped in first and nobody questioned what they said,” says psychologist Cameron Anderson, who led the study. “Dominant people seem really good at things because they speak with so much confidence.”

Source of Information : Scientific American Mind September-October 2009

Abruptly Forgotten

Written by Science Knowledge on 12:00 AM

Certain memories die suddenly rather than fading away

When you go from bed to bathroom on a dark night, a quick flick of the lights will leave a lingering impression on your mind’s eye. For decades evidence suggested that such visual working memories—which, even in daylight, connect the dots to create a complete scene as the eyes dart around rapidly—fade gradually over the span of several seconds. But a clever new study reported in the journal Psychological Science finds that such memories actually stay sharp until they are suddenly lost.

Cognitive psychologists Weiwei Zhang and Stephen J. Luck, both at the University of California, Davis, tested subjects’ recall for the hues of colored squares flashed briefly on a screen up to 10 seconds earlier. Subjects marked their answer on a color wheel. If memories decay gradually, the guesses should have become increasingly imprecise as time wore on, evidenced by participants selecting yellow or red, for example, when the correct choice was orange. Instead subjects went straight from fairly accurate answers to random choices—no better than chance—indicating the memories were decaying all at once. According to Zhang and Luck’s mathematical analysis, most subjects’ memories went “poof” somewhere between four and 10 seconds after the stimulus.

Researchers say a sudden die-off is to be expected if working memories are stored in circuits that feed back on themselves. Luck says the system is like a laptop as compared with a flashlight. “The laptop is an active system that uses feedback circuits to limit how much power it draws,” he says. So whereas a flashlight dims when it runs low on juice, “the computer runs perfectly normally while the battery drains,” he says, “until suddenly the laptop shuts off.”


Source of Information : Scientific American Mind September-October 2009

Smile! It Could Make You Happier

Written by Science Knowledge on 12:53 AM

Making an emotional face—or suppressing one—influences your feelings

We smile because we are happy, and we frown because we are sad. But does the causal arrow point in the other direction, too? A spate of recent studies of botox recipients and others suggests that our emotions are reinforced—perhaps even driven—by their corresponding facial expressions.

Charles Darwin first posed the idea that emotional responses influence our feelings in 1872. “The free expression by outward signs of an emotion intensifies it,” he wrote. The esteemed 19thcentury psychologist William James went so far as to assert that if a person does not express an emotion, he has not felt it at all. Although few scientists would agree with such a statement today, there is evidence that emotions involve more than just the brain. The face, in particular, appears to play a big role.

This February psychologists at the University of Cardiff in Wales found that people whose ability to frown is compromised by cosmetic botox injections are happier, on average, than people who can frown. The researchers administered an anxiety and depression questionnaire to 25 females, half of whom had received frown-inhibiting botox injections. The botox recipients reported feeling happier and less anxious in general; more important, they did not report feeling any more attractive, which suggests that the emotional effects were not driven by a psychological boost that could come from the treatment’s cosmetic nature. “It would appear that the way we feel emotions isn’t just restricted to our brain—there are parts of our bodies that help and reinforce the feelings we’re having,” says Michael Lewis, a co-author of the study. “It’s like a feedback loop.” In a related study from March, scientists at the Technical University of Munich in Germany scanned botox recipients with fMRI machines while asking them to mimic angry faces. They found that the botox subjects had much lower activity in the brain circuits involved in emotional processing and responses—in the amygdala, hypothalamus and parts of the brain stem—as compared with controls who had not received treatment.

The concept works the opposite way, too—enhancing emotions rather than suppressing them. People who frown during an unpleasant procedure report feeling more pain than those who do not, according to a study published in May 2008 in the Journal of Pain. Researchers applied heat to the forearms of 29 participants, who were asked to either make unhappy, neutral or relaxed faces during the procedure. Those who exhibited negative expressions reported being in more pain than the other two groups. Lewis, who was not involved in that study, says he plans to study the effect that botox injections have on pain perception. “It’s possible that people may feel less pain if they’re unable to express it,” he says.

But we have all heard that it is bad to repress our feelings—so what happens if a person intentionally suppresses his or her negative emotions on an ongoing basis? Work by psychologist Judith Grob of the University of Groningen in the Netherlands suggests that this suppressed negativity may “leak” into other realms of a person’s life.

In a series of studies she performed for her Ph.D. thesis and has submitted for publication, she asked subjects to look at disgusting images while hiding their emotions or while holding pens in their mouths in such a way that prevented them from frowning. A third group could react as they pleased.

As expected, the subjects in both groups that did not express their emotions reported feeling less disgusted afterward than control subjects. Then she gave the subjects a series of cognitive tasks that included fill-in-the-blank exercises. She found that subjects who had repressed their emotions performed poorly on memory tasks and completed the word tasks to produce more negative words—they completed “gr_ss” as “gross” rather than “grass,” for instance—as compared with controls. “People who tend to do this regularly might start to see the world in a more negative light,” Grob says. “When the face doesn’t aid in expressing the emotion, the emotion seeks other channels to express itself through.”

No one yet knows why our facial expressions influence our emotions as they seem to. The associations in our mind between how we feel and how we react may be so strong that our expressions simply end up reinforcing our emotions—there may be no evolutionary reason for the connection. Even so, our faces do seem to communicate our states of mind not only to others but also to ourselves. “I smile, so I must be happy,” Grob says.


Source of Information : Scientific American Mind September-October 2009

Dancing with the Starlings

Written by Science Knowledge on 1:30 AM

Birds’ rhythmic abilities offer clues to the origins of dance

Researchers have long assumed that humans were the only animals that could dance—even our close primate relatives cannot keep a steady beat or be taught to move to a rhythm. But new evidence shows that birds can dance, revealing that the mysterious ability could be a by-product of vocal learning.

Aniruddh Patel of the Neurosciences Institute, Adena Schachner of Harvard University and their colleagues studied several birds, among them a cockatoo that dances to the Backstreet Boys’ “Everybody.” When Patel sped up or slowed down the song, the bird adjusted its moves to match the tempo, eliminating the possibility that it was in sync with the music by chance. Intrigued, Schachner and her colleagues started searching YouTube for videos of other dancing animals. They found 15 bopping species (14 parrot and one elephant) that also share an additional trait: the capability to imitate sounds. That correlation suggests our musical ability grew out of the vocal learning
system instead of being “a special-purpose ability,” Patel says. The findings could help advance research on movement disorders, he adds. Hearing music helps Parkinson’s patients to walk, for example. So far scientists do not understand the underlying mechanisms, but if bird brains share certain key circuits with humans, then scientists may find answers by studying them.

Source of Information : Scientific American Mind September-October 2009

Say Cheese

Written by Science Knowledge on 1:26 AM

Kids’ smiles predict their future marriage success

Pictures of grinning kids may reveal more than childhood happiness: a study from DePauw University shows that how intensely people smile in childhood photographs, as indicated by crow’s feet around the eyes, predicts their adult marriage success. According to the research, people whose smiles were weakest in snapshots from childhood through young adulthood were most likely to report being divorced in middle and old age. Among the weakest smilers in college photographs, one in four ended up divorcing, compared with one in 20 of the widest smilers. The same pattern held among even those pictured at an average age of 10.

The paper builds on a 2001 study by psychologists at the University of California, Berkeley, that tracked the well-being and marital satisfaction of women from college through their early 50s. That work found that coeds whose smiles were brightest in their senior yearbook photographs were most likely to be married by their late 20s, least likely to remain single into middle age, and happiest in their marriage; they also scored highest on measures of overall well-being (including psychological and physical difficulties, relationships with others and general self-satisfaction).

The scientists speculate that one’s tendency to grin—an example of what psychologists call “thin slices” of behavior that can belie personal traits—reflects his or her underlying emotional disposition. Positive emotionality influences how others respond to a person, perhaps making that individual more open and likely to seek out situations conducive to a lasting, happy marriage. But there could be a more cynical explanation, according to Matthew Hertenstein, a psychologist at DePauw who led the new study. “Maybe people who look happier in photos show a social face to others,” he says. “Those may be the same people who are likely to put up with partners because they don’t want to appear unhappy.”


Source of Information : Scientific American Mind September-October 2009

Memory Maintenance

Written by Science Knowledge on 1:53 AM

As recollections age, different brain areas take charge of the upkeep

The brain’s ability to learn and form memories of day-today facts and events depends on the hippocampus, a structure deep within the brain. But is the hippocampus still maintaining the memory of, say, the commencement address at your college graduation 20 years ago? The latest evidence suggests that as memories age, the hippocampus’s participation wanes.

In a 2006 study, neuroscientist Larry R.Squire of the University of California, San Diego, and the Veterans Affairs San Diego Healthcare System studied patients who had hippocampal damage. These individuals did not remember details of newsworthy events that occurred in the five to 10 years prior to their injuries, but they did recall older events.

Building on those results, Squire turned to healthy brains. His team questioned 15 people in their 50s and 60s about events in the news over the past 30 years while scanning the participants’ brains with functional MRI. To single out brain activity related to the date of the event, the researchers separately evaluated activity tied to learning and remembering the test questions. They also accounted for the richness of participants’ recollections of events, to make sure the degree to which someone was able to recall an event did not influence the data.

Squire’s team reported in January that activity in the hippocampus steadily declined as subjects remembered events that were up to 12 years old. With more remote memories, the structure’s activity leveled off. In contrast, areas in the frontal, temporal and parietal lobes displayed increasing activity for recalled events from those dozen years, then reached a plateau during older remembrances.

The biology behind how the brain makes and keeps memories is not fully understood, Squire notes, but it appears that, initially, a memory resides in the hippocampus and in areas the structure connects to in the neocortex, the outer part of the cerebral cortex. “A time comes when the cortical regions important to a memory are connected [to one another] heavily enough to form a stable representation,” Squire says. “Then the hippocampus isn’t needed to hold the whole thing together.”

Source of Information : Scientific American Mind September-October 2009

Early Risers Crash Faster

Written by Science Knowledge on 1:22 AM

Night owls belie slacker reputation by staying alert longer

Early birds may get the best worms—or at least the best garage sale deals—but they also tire out more quickly than night owls do. In a new study researchers Christina Schmidt and Philippe Peigneux, both at the University of Liège in Belgium, and their colleagues first asked 16 extreme early risers and 15 extreme night owls to spend a week following their natural sleep schedule.

Then subjects spent two nights in a sleep lab, where they again followed their preferred sleep patterns and underwent cognitive testing twice daily while in a functional MRI scanner. An hour and a half after waking, early birds and night owls were equally alert and showed no difference in attention-related brain activity. But after being awake for 10 and a half hours, night owls had grown more alert, performing better on a reactiontime task requiring sustained attention and showing increased activity in brain areas linked to attention. More important, these regions included the suprachiasmatic area, which is home to the body’s circadian clock. This area sends signals to boost alertness as the pressure to sleep mounts. Unlike night owls, early risers didn’t get this late-day lift. Peigneux says faster activation of sleep pressure appears to prevent early birds from fully benefiting from the circadian signal, as evening types do.

Source of Information : Scientific American Mind September-October 2009

You Snooze, You Lose

Written by Science Knowledge on 1:19 AM

Getting enough rest promotes weight loss

Lose weight while you sleep? It sounds too good to be true—but recent research indicates that there is a connection between how much you weigh and the amount of shut-eye you get per night. Two hormones, ghrelin and leptin, help to control appetite. When you do not get enough rest, levels of ghrelin, which increases hunger, rise; levels of leptin, which promotes feelings of fullness, sink. A study in the May issue of Psychoneuroendocrinology found a significant disruption in nighttime ghrelin levels in chronic insomniacs. According to the study, this hormone imbalance leads insomniacs to experience an increase in appetite during the day, leading to weight gain over time.

In addition to creating an imbalance in ghrelin and leptin, sleep deprivation causes levels of the stress hormone cortisol to rise, which increases cravings for high-carb, highcalorie “comfort foods.” Furthermore, the brain secretes growth hormone during the deep-sleep phase, helping the body convert fat to fuel. Without enough deep sleep, fat accumulates. Sleep expert Michael Breus, clinical director of the sleep division at Southwest Spine & Sports in Scottsdale, Ariz., says that there is no magic number of hours people should sleep but that the average adult needs about five 90-minute sleep cycles per night, so 7.5 hours seems optimal as a minimum. But simply getting under the covers is probably not a sufficient strategy to achieve long-term weight loss, Breus says. “What these findings suggest is that there’s a new triad to achieving a healthy weight: diet, exercise and enough sleep.”

Source of Information : Scientific American Mind September-October 2009

Who Said That? - Specialized neurons sort out overlapping sounds

Written by Science Knowledge on 1:14 AM

We live in a world full of echoes. Sounds reverberate, bouncing off walls, buildings, rocks and any other nearby surface. These sound waves pile on one another and hurtle down your ear canals from different angles, the echoes from one noise jumbling together with new sounds and their echoes. In spite of that barrage, the neurons in the auditory midbrain, an area that responds before the auditory cortex does, are able to sort out which were the original sounds and where they came from. How they do so has long puzzled scientists, but new research suggests the trick is simpler than expected. In an April study, neuroscientists led by Sasha Devore at the Massachusetts Institute of Technology tested the widely held hypothesis that specialized cells in the brain actively suppress neuronal response to echoes. Using electrodes in a cat’s midbrain, researchers measured cells’ responses to a sound and its reverberations. They found that the cells that sense a sound’s direction of origin responded more strongly to the first 50 milliseconds of sound waves than they did to the later waves— their activity simply tapered off after the onset of the sound. The tapering response, a much simpler mechanism than the earlier theory of suppression, allows the brain to easily tune in to original sounds and pinpoint who or what is making noise.

Source of Information : Scientific American Mind September-October 2009

Pollution

Written by Science Knowledge on 1:19 AM

When you think about pollution, you probably imagine belching smokestacks and clouds of car exhaust. But most of the airborne particles that threaten your lungs are invisible. These silent drifters, called particulate matter, fill the air around you, whether you’re walking outdoors or sitting in the comfort of your home.

In the following sections, you’ll take a closer look at these microscopic particles. You’ll learn how they attack your lungs, and you’ll pick up a few practices to help control the risk. Finally, you’ll consider the very worst substance that humans regularly inhale—cigarette smoke.


The Size of the Problem
Unsurprisingly, particulate matter consists of tiny particles—vanishingly small bits of material formed through chemical reactions (say, burning fossil fuels) or shed from larger objects (like dust, pollen, and mold). Traditionally, environmental scientists distinguish between two broad categories of particulate matter, based on size:

• PM10 (pronounced “pee em 10”). These particles are smaller than 10 microns across, but larger than 2.5 microns. (For comparison, a human hair is about 60 microns thick and the finest beach sand is 90 microns.)

• PM2.5. These particles are the really tiny ones—they’re smaller than 2.5 microns thick.

Particles in these two categories act quite differently. PM2.5 particles are extremely light. They can travel hundreds of miles and stay aloft for weeks. PM10 particles can manage a few miles and a few hours, at best. But the most important distinction is the way these two particle types affect your lungs. When you breathe, you suck in lungfuls of air and particulate matter. Your respiratory system’s natural defenses trap many of these particles. They stick to the mucus-lined airways in your lungs. Once immobilized this way, tiny hairs called cilia slowly brush them back upstream and out of your lungs, so you can cough them out or swallow and destroy them with the digestive acids in your stomach.

But here’s the catch: The tiny PM2.5 particles travel deeper into your lungs. They’re less likely to get stuck in your passageways and more likely to travel all the way to the alveoli, where your blood absorbs oxygen. This poses a problem, because your alveoli aren’t able to sweep out foreign particles like the rest of your lungs can. Instead, the particulate matter can remain lodged in your alveoli indefinitely, eventually damaging lung function and contributing to diseases like emphysema and lung cancer. Furthermore, some substances can pass through the walls of alveoli and directly into your blood. This is another case of seriously bad news, because PM2.5 particles are more likely to include toxic substances like lead.

To take good care of your lungs, you should reduce your exposure to PM2.5 particles as much as possible. If you live in a large city, pay attention to the air-quality index, which soars when the air is thick with certain pollutants (including ozone, carbon dioxide, and particulate matter). When the index is high—often during hot, humid weather—the outside air is most likely to harm your lungs and aggravate medical conditions. On bad air days like these, just stay in. And whatever you do, avoid vigorous exercise when pollution is high. Many air experts believe a morning jog through the smog does more cardiovascular harm than good.

Source of Information : Oreilly - Your Body Missing Manual

Improving Your Voice

Written by Science Knowledge on 1:05 AM

It takes little more than a 10-dollar tape recorder to see that most people aren’t comfortable with their own voices. All your life, you listen to your voice from the inside, where it benefits from the booming resonance of your head. So it’s little surprise that when you record your voice from the outside and play it back, the result is a somewhat tinnier sound.

The resulting insecurity makes some people reluctant to speak up and project their voices in crowded places. It encourages others to retreat into the comfort of mumbles. Fortunately, there’s a solution. A bit of vocal practice can help you unlearn these bad habits and reclaim your voice. In the following sections, you’ll walk through a handful of fun, practical
ways to improve your speaking, whether you’re chairing a company meeting
or cruising a nightclub for a hot hookup.


Get comfortable
If you aren’t comfortable with your voice, no one else will be, either. So start by recording your voice in ordinary conversation and taking a close listen. This process has two key benefits: First, it lets you objectively hear the strengths and weaknesses of your speaking tone, so you can learn to improve it. Second, it helps you get accustomed to hearing your own voice. Over time, this can make you comfortable enough to speak up. You can use the recording trick to help you work alone on the following exercises, or you can team up with a partner and do them together.


The man in the mirror
In your quest to refine your voice, it often helps to work on something that seems unrelated but isn’t—your posture. Speakers who slouch tend to talk downward, take shallow breaths, and lose confidence—all characteristics that rob your voice of its projecting power. To keep an eye on yourself in real time, you can try an old radio trick— speaking in front of a mirror. Then, to boost your speaking energy, practice talking with an absurdly exaggerated grin on your face.


Slow speech
To practice this exercise, read the same paragraph from a book or newspaper several times. Each time, try to speak a little more slowly, while enunciating as clearly as possible (exaggerate if necessary). Continue doing this until you find the absolute slowest speed at which you can speak without sounding like you’re dozing off. Slow speech is a cornerstone of good oratory. Barack Obama has a notoriously relaxed words-per-minute rate, for example. Slow speech helps prevent you from constricting your voice, raising its pitch, or mumbling. A related skill is pausing, which experienced speakers use to shape long speeches into careful paragraphs that allow listeners to follow along easily. Many people who are uncomfortable speaking are even less comfortable pausing. It’s as though they’re afraid to give listeners the chance to reflect on their spotty oratorical skills. If this describes you, practice deliberately holding your pauses for longer than seems natural—say, a five-count.


Serial emphasis
Pick a simple sentence like “I never said he loved the maid.” Repeat the sentence, emphasizing the first word, then the second word, then the third word, and so on. For example, “I never said he loved the maid. I never said he loved the maid. I never said he loved the maid. I never said he loved the maid,” and so on. Exaggerate the difference to dramatize the sentence and change its meaning. This exercise helps boring speakers break out of their lazy monotone and wake up to the power of varied expression. A similar exercise is to take a well-known nursery rhyme and repeat it using different personalities (for example, using a tone that’s angry, delighted, confused, anxious, and so on).


Project the distance
Here’s a good group exercise to try in a large room: Organize people into pairs and arrange them in a circle or two lines so that the partners are facing each other. Ask the partners to have a conversation about something straightforward—for example, their day, current affairs, or a recent movie they saw. As they speak, call out “Back!” every 20 seconds, at which point everyone must take a step back. The challenge is for everyone to continue their conversation without being drowned out or distracted by the other conversations, and without resorting to shouting. (Making sure no one trips over a stray piece of furniture is also a good idea.) At the very end, when the partners are as far away from each other as possible, go through the pairs one by one. Each pair must then rush back together, holding their far-apart volume, and continue to talk for an additional 20 seconds at close proximity. The difference between their starting volume and their new, projected voice will be dramatic.

Source of Information : Oreilly - Your Body Missing Manual

Mucus Myths

Written by Science Knowledge on 1:43 AM

Mucus has a commanding place in our collective imaginations. Although you may have heard some of the following factoids about the sticky stuff that lines your airways, there’s not much more than a good story to back them up.

• Milk thickens mucus. People believe this bit of biological trivia so strongly that they really do report thicker mucus after drinking dairy products. But close analysis by mucus ologists has found no change in the amount of mucus or its consistency after drinking milk. This myth may be partly reinforced by the creamy mouth-feel of milk, which can leave a coating on the tongue and throat.

• Green mucus signals a bacterial infection. Ordinarily, mucus is thin and clear.
As your body battles an infection of any kind—bacterial or viral—your mucus will thicken and become yellow or green. (The green color is actually from an ironcontaining enzyme your immune system uses for its germ-fighting reactions.)

• Blowing your nose to expel mucus shortens a cold’s duration. Keeping a clean nose may reduce the chance of transmitting your cold. (Or not, as your immune system may have already neutralized the virus.) However, forceful nose blowing can drive viruses and inflammatory substances into your otherwise germ-free sinuses, possibly setting the stage for a sinus infection.

Source of Information : Oreilly - Your Body Missing Manual

Your Mucus

Written by Science Knowledge on 1:37 AM

One of the most notorious parts of your upper-respiratory tract is mucus, the thick, slippery coating that lines your breathing passages all the way to your lungs.

Mucus scores high on the list of Topics to Raise If You Never Want to Be Invited Out Again. However, biology nerds know there are many reasons to love your mucus. It plays essential defense and clean-up roles in your respiratory system, trapping nasty substances—from pollen and dust to bacteria and viruses. Without mucus, your nose would be in a perpetual state of dry discomfort, and you’d certainly be at more risk for nose and throat infections.

Many people associate mucus with colds and respiratory problems. While these conditions may cause your body to produce more mucus, they’re more likely to thicken your existing mucus and inflame your airways, disrupting your body’s normal mucus-disposal system and making you increasingly aware of the slimy stuff.

If you’re an average person, your respiratory system produces a healthy four cups of mucus over the course of a day. Ordinarily, the mucus in your nose collects airborne contaminants and flows silently down the back of your throat and into your stomach. Your stomach then digests this mucuscoated garbage. This design highlights the power of your stomach’s digestive juices. It also suggests that, when faced with dirt and disease-causing compounds, it’s often safer to eat them than to inhale them.

Source of Information : Oreilly - Your Body Missing Manual

The Dangerous Crossing

Written by Science Knowledge on 1:34 AM

One of the human body’s most notorious limitations is the way your feeding chute (your esophagus) passes just over your breathing tube (the trachea). A flap of cartilage called the epiglottis closes over your airway when you swallow to prevent food from slipping in. The problem is that the epiglottis isn’t foolproof. If you cough or try to talk while eating, you can force your epiglottis open. With bad timing and the wrong food, you can end up blocking your airway completely.

Life-threatening choking is distinctive: Silence is the most obvious symptom. Because people use the same passageways to breathe and talk, someone with a complete airway obstruction will be almost completely unable to speak, gurgle, cough, or wheeze. You know what comes next—the Heimlich maneuver (also known as abdominal thrusts), as you’ve seen in countless television movies. But don’t act yet, because modern first-aid procedures suggest this sequence:

• Encourage the person to try to cough.

• Slap the person’s back 5 to 20 times, using the heel of your hand. The goal is to create vibrations that can dislodge an obstruction.

• Now it’s time for abdominal thrusts—a risky but potentially life-saving move. Stand behind the person and wrap your hands around his abdomen, just above the belly button. This is where you’ll find the diaphragm, the muscle that sits just under the lungs and controls breathing. Make a fist with one hand, and wrap your other hand around it. Then pull your fist upward and inward, forcefully. You may need to repeat the move several times. Done right, abdominal thrusts increase the pressure in the lungs and hopefully blow out the lodged object. (They may also bruise the abdomen and fracture a rib.)

Source of Information : Oreilly - Your Body Missing Manual

The Nasal Cycle

Written by Science Knowledge on 1:30 AM

Your nose has a bit of built-in redundancy. Although you could survive perfectly well with a single nostril, your nose holds two parallel breathing passages that are divided by a thin wall of cartilage called the septum. These passages meet at the back of your throat, where they take a single tunnel down to your lungs.

So why do you have two nostrils? Most people don’t spend much time comparing them, and simply assume that the second one is there to take over when the first one is blocked—say, by a nasty cold or an antisocial finger. But the reality is subtler and stranger.

Your two nostrils shift their workload back and forth in a delicate dance called the nasal cycle. At any moment, most of the air you inhale travels through just one nostril, while a much smaller amount seeps in through the other. At some point, the nasal cycle reverses course and the workload shifts to the other nostril. The length of time between nostril switching varies, depending on the individual and various other factors, but each cycle usually lasts from 40 minutes to several hours. (That’s why you often have intermittent periods of easy breathing even when you suffer from a heavy cold. In this case, one nostril is plugged more than the other.)

For the longest time, scientists had no idea why the nasal cycle took place. After all, your nostrils aren’t doing much work, so there’s no reason they need hours of idle time. But recent research has uncovered the apparent reason: nostril switching improves your sense of smell.

To understand why, you need to realize that the nasal cycle changes the way air passes through your nose. In your dominant nostril, the air moves very quickly. In your other nostril, it seeps through more slowly.

This difference is important because odor-causing chemicals vary in the amount of time they take to dissolve through the mucus that lines your nasal cavity. Chemicals that dissolve quickly have the strongest effect in a fast-moving airstream that spreads them out over as many odor receptors as possible. But chemicals that dissolve slowly are easier to smell in a slow-moving airstream. If the air rushes by too quickly, the chemicals will be whisked away before they’ve reached any odor receptors. That’s why your nose has both a fast road and a slow lane. Quite simply, the combination of two nostrils with different airflows gives you a more detailed“smell picture” of the world around you. Incidentally, your nose performs nostril switching using special erectile tissue that swells to narrow the passageway in the nostril that’s taking a break. Collectors of bizarre body trivia take note: It’s the same sort of erectile tissue that’s at work in male and female reproductive organs.

Source of Information : Oreilly - Your Body Missing Manual

Snoring: The Nightly Thunder

Written by Science Knowledge on 1:20 AM

A great many pleasant sounds can come out of a person’s airways, but snoring isn’t one of them. In fact, loud snoring can generate the same volume as an average lawnmower (which you definitely wouldn’t invite into bed with you). For this reason, the effects of snoring are usually felt first by whoever has the misfortunate of sharing your bed. Technically, snoring occurs when the passageways at the back of your throat become partially blocked, causing the soft tissues in and around your throat to vibrate noisily. Nearly half of all adults have an occasional snoring episode, and about a quarter are chronic snorers. On its own, snoring may be harmless (for the snorer). However, if you bed down with a snorer, you may suffer from interrupted sleep, stress, and even hearing loss.

Furthermore, snoring can be a sign of a much more serious problem, called sleep apnea, where the sufferer repeatedly stops breathing during sleep. With serious sleep apnea, interruptions can occur more than a dozen times per hour and can last 1 or 2 minutes. The result is that the sufferer never gets proper sleep, spends most of the day in a dangerous haze, and is at increased risk of heart disease.

If you’re an occasional or frequent snorer, avoid the three most common aggravating factors: smoking, being overweight, and quaffing alcohol in the hours before bed. (Alcohol relaxes the muscles in the back of your throat, making it easier for them to flap loudly together.) You can also try sleeping on your side—a simple switch that immediately reduces the nightly emanations of many a problem snorer. (To train yourself to side-sleep, take a shirt that has a pocket in the front, put a tennis ball in the pocket, and wear the shirt backwards.) If you’re still suffering, or you suspect sleep apnea, contact a doctor who can investigate. Possible remedies range from surgery to a dental appliance that you wear while you sleep.

Source of Information : Oreilly - Your Body Missing Manual

Holding Your Breath

Written by Science Knowledge on 1:11 AM

In the short term—say, two or three minutes—you have complete control over your ability to hold your breath. But try to hold it for much longer and you’ll run into your body’s stubborn survival instinct.

As you hold your breath, the level of oxygen in your blood begins to sink. At the same time, the level of carbon dioxide—the waste left over from your body’s energy generating operations—starts to rise. Interestingly, it’s the change in the carbon-dioxide level that your body really notices. Your brain detects this increase and eventually triggers an overwhelming urge to resume breathing.

Reckless divers sometimes take advantage of biology to increase their breath-holding time by hyperventilating before they dive. (To hyperventilate is to suck in more air than you actually need, usually by taking quick, deep breaths.) After hyperventilating, the diver feels a reduced urge to breathe and can stay underwater longer. This isn’t because he’s loaded up on oxygen (he isn’t). Rather, it’s because he’s lowered the amount of carbon dioxide in his body. As a result, it takes longer to trigger the brain’s safety mechanism that forces the diver to start breathing again. This practice is dangerous on several counts. The most obvious risk is that both oxygen deprivation and carbon dioxide overload lead to dizziness and can cause a blackout, which will leave the diver lying quietly unconscious at the bottom of a body of water.

Incidentally, the current record for breath-holding is a staggering 17 minutes, set by the endurance artist David Blaine. To pass the 5-minute mark, Blaine employs several specialized techniques. Most important is the mammalian diving reflex—an evolutionary throwback that causes the human body to lower its heart rate and blood pressure quickly when submerged in cold water, thereby conserving oxygen. Also important is inhaling pure oxygen rather than air (which allows practiced breath-holders to double their breath-free time) and using a trick called lung packing (swallowing hard to force more air into the lungs). All the rest is practice and masochism.

Source of Information : Oreilly - Your Body Missing Manual

A Universal Course for Dealing with Death

Written by Science Knowledge on 1:55 AM

Legions of mental and medical health professionals who work with the elderly memorize this acronym: DABDA. It stands for the five stages of coping with death popularized by Swiss-born psychiatrist Elisabeth Kübler-Ross in the late 1960s: denial, anger, bargaining, depression and acceptance. These stages describe a sequence of transitions that all people supposedly pass through on finding out they are about to die. According to Kübler-Ross, when we learn of our impending demise, we first tell ourselves it is not happening (denial), then become angry at the realization that it actually is (anger), next search in vain for a way to postpone the death, perhaps until we can accomplish a desired goal (bargaining), later become sad as the awareness that we are dying sets in (depression), and finally come to grips with our inevitable demise and accept it with equanimity (acceptance).

Many medical, nursing and social work students in North America and Britain learn about Kübler-Ross’s stages as part of their professional training. These stages also pervade our culture and now extend beyond death in the popular mind-set to the psychological processing of grief from any significant disappointment. In the sitcom Frasier, the main character passes through all five stages of grief after losing his job as a radio talk-show psychologist. And in The Simpsons, Homer experiences the same sequence of emotions in a matter of seconds after a doctor informs him (erroneously) that he is dying.

Despite its popularity, Kübler-Ross’s theory is surprisingly devoid of scientific support. Studies reveal that many dying patients skip one or more Kübler-Ross stages or even pass through the stages in reverse order. For example, some people initially accept their own deaths but enter denial later. Nor does research bear out the validity for these stages for grief. Not all people experience depression or marked distress after the loss of loved ones, including partners or family members to whom they were deeply attached, according to research by Columbia University psychologist George Bonanno and his colleagues. Moreover, in a 2007 study of 233 Connecticut residents who had recently lost a spouse, acceptance, not denial, was the predominant initial reaction following loss. Kübler-Ross stages may be appealing because they offer a sense of predictability over an event that is out of our control. The idea that the frightening experience of death can be boiled down to a set series of defined stages that culminate in tranquility is reassuring. In truth, however, the process of dying does not follow the same path for all of us, no more than does the process of living. We can all be fooled by psychomythology, because so many of its falsehoods dovetail with our intuitions, hunches and experiences. Thus, scrutinizing popular psychology claims can provide a new window onto our mental worlds and enable us to make better life decisions. As paleontologist and science writer Stephen Jay Gould reminded us, debunking a myth necessarily unveils an underlying truth, thereby allowing us to attune our expectations more squarely with reality. In this way, taking on psychomythology, example by example, can transform us into better informed and educated citizens.

Source of Information : Scientific American Mind March-April 2010

Older and Sadder

Written by Science Knowledge on 1:51 AM

Think of someone who is depressed, cantankerous, lonely, sexually inactive and forgetful. Did an elderly person come to mind? In one survey, 65 percent of psychology students agreed that “most older people are lonely and isolated,” and in another survey, 64 percent of medical students agreed that “major depression is more prevalent among the elderly than among younger persons.” Exposure to dubious media depictions of the aged begins early in life. In a study of Disney children’s films, investigators found that 42 percent of elderly characters are portrayed in a less than positive light and as forgetful or crotchety.
Such unflattering renderings also pervade films aimed at adolescents. In a study of popular teen movies, most elderly characters exhibited some negative characteristics, and a fifth fulfilled only off-putting stereotypes.

Contradicting these representations, one research team surveyed adults between the ages of 21 and 40 or older than 60 about their own happiness as well as about their assessment of the happiness of the average person at their current age, aged 30 and aged 70. Young adults predicted that people would become less happy as they got older. Yet older adults were actually happier than younger respondents. Population-based surveys reveal that rates of depression are highest in those between the ages of 25 and 45 and that the happiest group overall is men aged 65 and older. Happiness increases through the late 60s and perhaps even 70s. In one study of 28,000 Americans, a third of 88-year-olds reported being “very happy,” and the happiest individuals surveyed were the oldest. Indeed, the odds of being happy increased 5 percent with every decade Interestingly, research by Stanford University psychologist Laura Carstensen demonstrates that compared with younger people, older people are more likely to recall positive than negative information, perhaps accounting partly for their often surprisingly rosy outlook on life. Older people are not generally lacking in sexual desire either. In a national survey, more than three quarters of men aged 75 to 85 and half of their female counterparts reported interest in sex.

Moreover, 73 percent of people between the ages of 57 and 64 were sexually active, as were 53 percent of those 64 to 74 years old. Among 75- to 85-year-olds, 26 percent said they were sexually active. Finally, cognitive abilities do not fade dramatically with age. We do experience some memory loss as the years pass, especially minor forgetfulness and difficulty retrieving words while speaking. Our ability to manipulate numbers, objects and images may also decline some in our later years. But even at age 80, in the absence of serious illness affecting the brain, general intelligence and verbal abilities are not much worse than they were decades earlier. Furthermore, research on creative accomplishments indicates that in some disciplines, such as history or fiction writing, many people produce their best work in their 50s or even decades later. Thus, to tweak an old saying, “You can teach an old dog new tricks … and a lot more.”

Source of Information : Scientific American Mind March-April 2010

One Drink, One Drunk

Written by Science Knowledge on 1:56 AM

Can ex-alcoholics eventually drink in moderation without succumbing to their old addiction? One survey of more than 3,000 people reveals that only 29 percent of Americans think they can. This perception dovetails with the Alcoholics Anonymous (AA) slogan, “One drink, one drunk.” AA’s familiar 12-step program encourages members to admit that they are powerless over alcohol. Treatment programs premised on the 12 steps boast recovery rates as high as 85 percent. But here’s the rub: as many as two thirds of drinkers drop out within three months of joining AA, and AA helps only about a fifth of people abstain completely from alcohol. Claims that some people with a history of alcoholism can safely engage in “controlled drinking” have generated a firestorm of controversy. Yet a 2001– 2002 National Institute on Alcohol Abuse and Alcoholism survey of more than 40,000 adults revealed that 18 percent of one-time alcoholics could drink in moderation without abusing alcohol, challenging the popular assumption that abstinence is a necessary goal for all alcoholics.

Further, researchers have found that behavioral self-control training programs, in which moderate drinking is the goal, are at least as effective as those that use the 12-step method. In these restraint-centered programs, therapists train people to monitor their drinking, set limits for their alcohol consumption, control their rate of drinking and reward their progress. These programs also teach coping skills that help participants “wait out” the urge to drink and to avoid situations that tempt them to drink. Such tactics do not work for everyone. Studies suggest that if individuals are severely dependent on alcohol, have a long history of unhealthy drinking, and experience physical and psychological problems from drinking, they are probably best off seeking treatment programs that advocate abstinence. Nevertheless controlled drinking is probably a feasible goal for some ex-alcoholics. Indeed, problem drinkers may seek help earlier if they know that complete abstinence from alcohol is not the only alternative. Indeed, controlled drinking may be especially worth considering for patients for whom abstinence-oriented programs have repeatedly failed to work.

Source of Information : Scientific American Mind March-April 2010

Positive Thinking Cures Cancer

Written by Science Knowledge on 1:00 AM

In the book 9 Steps for Reversing or Preventing Cancer and Other Diseases (Career Press, 2004), Shivani Goodman argues that her cancer was the product of negative thought patterns—in this case, her subconscious rejection of being a woman. Once she identified her toxic attitudes, Goodman claims, she changed them into healing approaches that created “radiant health.” Numerous selfhelp books similarly imply that a positive attitude can stop cancer in its tracks or at least slow its progression.

Most women who have survived cancer seem to agree. According to surveys,
40 to 65 percent of survivors believe their cancers were caused by stress, and between 60 and 94 percent think they became cancer-free because of their positive attitude.

The weight of the evidence, however, fails to support the notion that optimism is a salve for cancer. Most studies find no connection between cancer risk and either stress or emotions. In fact, in several investigations, researchers observed a lower risk of breast cancer among women who experienced relatively high stress in their jobs, compared with women who experienced relatively low job stress. Scientists have also consistently failed to turn up an association between positive attitude and cancer survival.

For such reasons, journalist and social critic Barbara Ehrenreich adopts a decidedly skeptical stance on the power of mind-set over healing in her book Bright-Sided: How the Relentless Promotion of Positive Thinking Has Undermined America (Metropolitan Books, 2009). Further, Ehrenreich rails against the “cancer culture” that pressures people with cancer to believe that being upbeat and cheerful will heal them or at least ennoble them as human beings. Instead Ehrenreich urges people with breast cancer to adopt an attitude of “vigilant realism” and not to bury themselves under a cosmetic veil of cheer. The impotence of a positive outlook in the face of physical ailments calls into question the medical value of support groups and the emotional assistance they provide. Early preliminary studies seemed to suggest that participating in such groups helps to prolong life. But more recent and scientifically solid research, reviewed by University of Pennsylvania psychologist James Coyne and his colleagues, showed that psychological interventions (including support groups) do not extend the lives of cancer patients, although they can enhance their quality of life. People with cancer can relieve their physical and emotional burdens by seeking quality medical and psychological care, connecting with friends and family, and finding meaning and purpose in every moment. They can also take comfort in the now well-established finding that their attitudes, emotions and stressful experiences are not to blame for their illness.

Source of Information : Scientific American Mind March-April 2010

Different Strokes for Different Pupils

Written by Science Knowledge on 1:41 AM

In the story “Parents of Nasal Learners Demand Odor-Based Curriculum,” writers at the satirical newspaper The Onion poked fun at the idea that a teaching style exists to unlock every underperforming student’s latent potential. An expert quoted in the story observed that “nasal learners often have difficulty concentrating and dislike doing homework. . . . If your child fits this description, I would strongly urge you to get him or her tested for a possible nasal orientation.”

Plug the words “learning styles” into an Internet search engine, and you’ll find scores of Web sites purporting to diagnose your preferred learning style in a matter of minutes. These sites are premised on a widely accepted claim: students learn best when teaching styles are matched to their learning styles. The popularity of this view is understandable. Rather than implying that some students are better or worse learners overall, it suggests that all students can learn well, perhaps equally well, given just the right teaching style. This idea has become a truism in much of recent educational theory and practice. It has been extolled in many popular books and in workshops that attract hundreds of teachers and principals. In some schools, teachers have even started giving children T-shirts emblazoned with one of the letters V, A and K, which stand for three widely accepted learning styles: visual, auditory and kinesthetic.

Yet studies show that students’ learning styles are difficult to reliably identify, largely because they often differ greatly across situations. A child might display one style in art class, say, and a different one when trying to learn math.

Moreover, from the 1970s onward, most investigations have failed to show that matching teaching styles to learning styles works: for example, it does not improve students’ grades in most cases. Instead certain general teaching approaches— such as setting high expectations for students and providing them with the motivation and skills to attain them— usually yield better results than other strategies, regardless of students’ learning styles.

To the extent that the “matching” approach encourages educators to teach to students’ intellectual strengths rather than their weaknesses, it may actually backfire. In the long run, students need to learn to compensate for their shortcomings, not avoid them.

Source of Information : Scientific American Mind March-April 2010

Blowing Our Tops Defuses Anger

Written by Science Knowledge on 1:24 AM

People often opine that releasing anger is healthier than bottling it up. In one survey, 66 percent of university undergraduates agreed that expressing pentup anger is a good way of tamping down aggression. This belief dates back at least to Aristotle, who observed that viewing tragic plays affords the opportunity for catharsis, a cleansing of anger and other negative emotions. Popular media also assure us that anger is a monster we must tame by “letting off steam,” “blowing our top” and “getting things off our chest.” In the
2003 movie Anger Management, the meek hero (played by Adam Sandler) is falsely accused of “air rage” on a flight, causing a judge to order him to attend an anger management group run by psychiatrist Buddy Rydell (played by Jack Nicholson). At Rydell’s suggestion, Sandler’s character tosses dodgeballs at schoolchildren and throws golf clubs to purge his anger.

Rydell’s advice echoes the counsel of many self-help authors. One suggested that rather than “holding in poisonous anger,” it is better to “punch a pillow or a punching bag. And while you do it, yell and curse and moan and holler.” Some popular therapies encourage clients to scream, hit pillows or throw balls against walls when they get angry. Practitioners of Arthur Janov’s “primal therapy,” popularly called primal scream therapy, believe that psychologically disturbed adults must bellow at the top of their lungs or somehow otherwise release the emotional pain stemming either from the trauma of birth or from childhood neglect or suffering.

Yet more than 40 years of research reveals that expressing anger actually amplifies aggression. In one study, people who pounded nails after someone insulted them became more critical of that person than did their counterparts who did not pound nails. Other research shows that playing aggressive sports, such as football, actually boosts self-reported hostility. And a review of 35 studies by psychologist Craig Anderson of Iowa State University and psychologist Brad Bushman of the University of Michigan at Ann Arbor suggests that playing violent video games such as Manhunt, in which participants rate assassinations on a five-point scale, heightens aggression in the laboratory and in everyday social situations.

Psychologist Jill Littrell of Georgia State University concludes from a published review of the literature that expressing anger is helpful only when accompanied by constructive problem solving or communication designed to reduce frustration or address the immediate source of the anger. So if we are upset with our partner for repeatedly ignoring our feelings, shouting at him or her is unlikely to make us feel better, let alone improve the situation. But calmly and assertively expressing our resentment (“I realize you probably aren’t being insensitive on purpose, but when you act that way, I don’t feel close to you”) can often take the sting out of anger.

Why is this myth so popular? People probably attribute the fact that they feel better after expressing anger to catharsis, rather than to the anger subsiding on its own, which it almost always does. Odds are, they would have felt better if they had merely waited out their anger.

Source of Information : Scientific American Mind March-April 2010

Programs of Persuasion

Written by Science Knowledge on 1:23 AM

Psychologist Robert Cialdini of Arizona State University has spent his entire career observing influence techniques not just in the lab but also in the real world. Cialdini has published his conclusions in a book, Influence: Science and Practice, fifth edition (Allyn & Bacon, 2008), where he identifies six core principles of social influence—all of which, he argues, have evolutionary underpinnings reaching far back into our ancestral history.

These core principles are as follows:

1. Reciprocity—we feel obligated to return favors.

2. Liking—we have a tendency to say yes to people whom we like.

3. Scarcity—we place more value on things that are in short supply.

4. Social proof—we look at what others are doing when we’re not sure what to do ourselves.

5. Authority—we listen to experts and those in positions of power.

6. Commitment and consistency—we like to be true to our word and finish what we’ve started.

All of these principles tap (somewhat self-evidently given their evolutionary origins), one way or another, into issues of primeval survival—issues that in the 21st century are perhaps recapitulated a little more often than we think. What will happen if I don’t fill up with gas? we mutter to ourselves in a fuel crisis (scarcity). Or at dinner: everyone else is using that funny-shaped spoon with the hook, so it’s got to be right. Right? (Social proof.) Because of this evolutionary lineage and of the strategies’ explicit connection to ostensibly individual reward systems, they are all subsumed within the supersuasion model under the broader, more generic principle of perceived self-interest.

Source of Information : Scientific American Mind March-April 2010

The Power to Persuade - Empathy

Written by Science Knowledge on 1:18 AM

In the summer of 1941 Sergeant James Allen Ward was awarded a Victoria Cross for bravery for clambering onto the wing of his Wellington bomber and, while flying 13,000 feet above the North Sea, extinguishing a fire in the starboard engine. He was secured, at the time, by just a single rope tied around his waist. Some time later Winston Churchill summoned the shy and swashbuckling New Zealander to Number 10 Downing Street to congratulate him on his exploits. They got off to a shaky start. The fearless, daredevil airman, tongue-tied in the presence of the prime minister, was completely unable to field even the simplest of questions put to him. Churchill tried something different. “You must feel very humble and awkward in my presence,” he began. “Yes, sir,” replied Ward. “I do.” “Then you can imagine,” Churchill said, “how humble and awkward I feel in yours.”

A brilliant double stroke of empathy—feeling the discomfort of his visitor and recasting it as though begging for the visitor to feel his—showed Churchill at his most disarming and persuasive. A warm, empathetic style will often convince people of your best intentions and bring them onboard. Empathy has been shown to be important in the doctor-patient relationship, in which physicians have to convince patients that they care about them and have their best interests at heart. This tactic not only makes for good medicine, it also has been shown to protect doctors from malpractice lawsuits.

In 2002 Nalini Ambady, now a professor of psychology at Tufts University, divided physicians into two groups: those who’d been dragged through the court and those who hadn’t. She made audiotapes of the doctors and their patients in session and then played the tapes to a group of students. The students were asked to determine which doctors had been sued. But there was a catch. For each of the recordings the output was “content-filtered.” All the students could hear was prosody: muffled, low-frequency garble, as if they were listening underwater. How, linguistically, would the doctors measure up? Could the students, on the basis of intonation alone, somehow distinguish one group from another? The results were unequivocal: they could tell them a mile off. The doctors who had been sued sounded way more self-important. They had a dominant, hostile, less empathic conversational style—whereas those who had not been sued sounded warmer. Forgive and forget? Live and let live? Only, it seems, if I like you.

The position of incongruity at the center of the SPICE model reflects its centrality to the idea of supersuasion. From calming someone down to raising someone’s spirits, from closing the deal to trying to bum a quarter from strangers on the street, defiance of expectation, script reversal, antithesis—call it what you will—lies at the very heart of supersuasion. Not only does incongruity enhance the aesthetic prowess of simplicity, it also knocks out the brain’s surveillance mechanisms and thereby enables the rest of the SPICE task force to secretly slip in under the radar and hotwire our neural pleasure centers.

Source of Information : Scientific American Mind March-April 2010

The Power to Persuade - Confidence

Written by Science Knowledge on 1:14 AM

Confidence, misplaced or otherwise, is catching. It’s a privileged, though sometimes precarious, condition, fiercely independent of reality, that’s transmitted sub-radar from one individual to another via language, belief and appearance. It’s why con men enjoy their appellation, and why McDonald’s and Nike bring out ads that declare “Just Do It” and “I’m Loving It,” as opposed to ads that say “I’m Thinking about It” or “I Kind of Like It.” Influence without confidence is about as useful as an inflatable dartboard.

Our reliance on confidence to help divine correctness— our deployment, that is, of a confidence heuristic—has been demonstrated in the lab. In 2008 Hilke Plassman, now associate professor of marketing at INSEAD Business School near Paris, sneakily switched the price tags on bottles of Cabernet Sauvignon. For some it was valued at $10, for others at $90.

Would the difference in price be reflected in a difference in taste? It sure would. Volunteers rated the $90 bottle considerably more drinkable than the $10 bottle—even though both bottles, unbeknownst to them, contained exactly the same wine. And that wasn’t all. Subsequently, during a functional MRI scan Plassman found that this simple sleight of mind was actually reflected anatomically, in neural activity deep within the brain. Not only did the “cheaper” wine taste cheaper and the “dearer” one, well, dearer; the supposedly more expensive wine generated increased activation in the medial orbitofrontal cortex, the part of the brain that responds to pleasurable experiences.

Similar results have also been found with experts. In 2001 cognitive psychologist Frédéric Brochet, then at the oenology research and teaching unit at the University of Bordeaux in France, took a midrange Bordeaux and served it in two different bottles. One was a labeled as a splendid grand cru, the other as a vin du table. Would the wine buffs smell a rat? Not a chance. Despite the fact that, just as in the Plassman study, they were actually being served the same vintage, the experts appraised the different bottles differently.

The grand cru was described as “agreeable, woody, complex, balanced and rounded,” whereas the vin du table was evaluated less salubriously—as “weak, short, light, flat and faulty.” Confidence is a wormhole into truth. In ambiguous, dynamic or fluid situations, not only does it have the right air—it also has the air of being right.

Source of Information : Scientific American Mind March-April 2010

The Power to Persuade - Fetal Attraction

Written by Science Knowledge on 1:02 AM

Let’s say you found a wallet on the street. What would you do? Take it to the nearest police station? Mail it back to the owner? Keep it? The answer, it emerges, depends less on a question of individual morality and a great deal more on our collective evolutionary heritage. In 2009 psychologist Richard Wiseman of the University of Hertfordshire in England left a bunch of wallets on the streets of Edinburgh, Scotland, each of which contained one of four photographs: a happy family, a cute puppy, an elderly couple and a smiling baby. Which ones, he wondered, would be most likely to find their way home? There was no doubting the outcome: 88 percent of the wallets containing the picture of the smiling baby were returned, beating all the others out of sight. The result, according to Wiseman, is not surprising. “The baby kicks off a caring feeling in people,” he says, a nurturing instinct toward vulnerable infants that has evolved to safeguard the survival of future generations.

In 2009 Melanie Glocker of the Institute of Neural and Behavioral Biology at the University of Muenster in Germany flashed pictures of newborns to a group of childless women while they underwent functional MRI. Using a special imageediting program, Glocker manipulated the pictures so that some of the infant faces incorporated higher “baby schema” values (large, round eyes; round, chubby face) whereas some had lower values (smaller eyes; narrower face). It wasn’t just the program that was eye-opening. Results revealed that the faces with higher baby schema values precipitated an increase in activity not just in the amygdale (the brain’s emotional control tower) but also in the nucleus accumbens, a key structure of the mesocorticolimbic system that mediates reward. Similar findings to Glocker’s have also been demonstrated acoustically. Kerstin Sander of the Leibnitz Institute for Neurobiology in Germany compared amygdala responses to infants and adults crying and discovered something extraordinary: a 900 percent increase for babies. Additional research has taken things one stage further and revealed that although preverbal infant vocalizations do indeed increase amygdala activation, it is sudden and unexpected changes in crying pitch that convey the most emotion—further support for the role of incongruity in supersuasion.

Source of Information : Scientific American Mind March-April 2010

The Power to Persuade - Incongruity

Written by Science Knowledge on 1:06 AM

The persuasive power of humor is second to none. If someone can make you laugh while trying to change your mind, chances are they’re on to a winner. Not long ago in London, I walked past a homeless man selling a copy of the magazine the Big Issue, the proceeds of which go toward helping those living on the street. “Free delivery within 10 feet!” he called out. I bought one on the spot. Precisely why humor is so powerful an influencer is an interesting question. The answer lies in one of its key ingredients, incongruity. The best jokes are the ones we don’t see coming, and because we don’t see them coming, they violate expectation.

Our brains do a double take. And in that fraction of a second, while their backs, so to speak, are turned, our brains are open to suggestion. The neurology of incongruity—what happens inside the brain as it is doing a double take—is well documented. Single cell recordings in monkeys show that the amygdala, the emotion center of the brain, is more sensitive to unexpected than expected presentations of both positive and negative stimuli. In humans, intracranial EEG recordings reveal increased activation in both the amygdala and the temporoparietal junction, a structure involved in novelty detection, on exposure to unusual events. Such findings confirm that incongruity not only gains our attention (a crucial component of any effective persuasion—just ask the guy in business class who complained about his dinner) but that it also lobs a stun grenade between our ears. It disables cognitive functioning and compromises, for a brief but critical time window, our neural homeland security.

Yet incongruity isn’t just about distraction. It’s also about reframing—as a study by social psychologist David Strohmetz and his co-authors at Monmouth University demonstrated rather fiendishly in 2002. The study in question was conducted in a restaurant, and Strohmetz began by dividing diners up into three groups, according to how many candies the waiter handed out with the check. To one group of diners the waiter gave one candy. To another, he gave two. And to the third—and this is where it gets interesting—he did the following. First he gave out one candy and then walked away . . . then turned back around, as if he had changed his mind, and added another. So one group got one candy. And two groups got two. But the two who got two were given them in different ways. (I hope you’re paying attention—there’s a test later.)

Did the number of candies and the manner in which they were allocated bear any relation to tip size? You bet it did. Compared with a control group of diners who got no candies at all (charming), those who got one tipped, on average, 3.3 percent higher. Similarly, those who got two candies tipped 14.1 percent higher. But the biggest increase was shown by those who received first one candy, then another—a biblical escalation of philanthropic zeal 23 percent greater than their uncandied brethren. That unexpected change of heart completely reframed the situation. It instigated a whole new way of appraising the interaction. He’s giving us special treatment, the diners thought to themselves. Let’s give him something back.

Source of Information : Scientific American Mind March-April 2010

The Power to Persuade - The Persuasion Instinct

Written by Science Knowledge on 1:03 AM

“You looking at my girl?” How many times has that particular question drawn an evening out to a close? Not so with elephants. During the mating season young male elephants, when they inadvertently encroach on females in estrus, give off what is known as an innocent scent, an olfactory signal to adult bull elephants that they are going to toe the line. How many times have houseguests outstayed their welcome, because despite all your hints they somehow just didn’t get that it was time to go? Not so with the thorny acacia tree of Central Africa. When insects start feeding on the thorny acacia too greedily, it produces a toxin that turns Michelin-starred leaves into pig swill. Not only that, it also gives off an odor, warning nearby acacias to put up the shutters themselves: an arboreal, chemical Twitter that there’s a freeloader doing the rounds. Examples such as these provide a pretty good flavor of how persuasion works in the animal kingdom. And it leaves what we humans do in the dust. There are no mixed messages, no beating around the bush (unless that bush happens to belong to a cassowary in which case the phrase takes on a different, more ominous meaning) and no sitting down over coffee to talk about it. Instead, in the absence of consciousness and those ephemeral containers of meaning we call words, animals rely on what ethologists call key stimuli: environmental triggers (such as the innocent scent in elephants and the not so innocent scent in acacias) that initiate, when they are activated, instinctive behavioral responses.

Source of Information : Scientific American Mind March-April 2010

The Power to Persuade - Perceived Self-Interest

Written by Science Knowledge on 1:00 AM

Several million years ago, when social networking was even more important than Facebook and Twitter are today, the facility to be true to one’s word, and to return favors accordingly, was synonymous with group cohesion. With individual cohesion, too: in the days before welfare and pest control, being ostracized was fatal.

But old evolutionary habits die hard—and the spectral remnants of exigencies past hover like neural phantoms on the dark, primeval stairwells of the brain. Take loyalty cards, for example. In 2006 psychologists Joseph Nunes and Xavier Dreze of the Wharton School of Marketing at the University of Pennsylvania presented the patrons of a car wash with two different types of voucher—each of which, when completed, entitled the beneficiary to a free visit. In both cases, eight stamps (corresponding to eight visits) were required to redeem the offer. But the vouchers differed from each other in one important feature. One consisted of eight blank circles, whereas the other consisted of 10, with the first two circles already voided out. Which of the vouchers do you think proved the more effective? You got it—the one with the first two stamps thrown in ostensibly “for free.” Of the customers given the 10-circle voucher, 34 percent fulfilled the promotional requirements and returned to the garage the stipulated eight times to claim their free car wash, compared with just 19 percent of the customers who weren’t on the empirical fast track. Even though the offer was exactly the same for both groups—customers had to visit the car wash on eight occasions to earn their freebie—those initial two tokens created a powerful illusion: not only of something for nothing (a gesture of corporate goodwill triggering reciprocity) but also of client commitment.

On receiving the vouchers that apparently gave them a two-point lead, customers thought to themselves: “Hey, I’m a fifth of the way there already. I might as well keep going.” And so they were far more likely to continue with the scheme than those who had started supposedly from scratch. This voucher trick is all about the art of framing— the presentation of information in a way that maximizes positive outcomes. And framing isn’t just confined to advertising. Politicians do it. Attorneys do it. We all do it. The key, as a persuader, is to present things in such a way that they appear to be not in your own best interests—but in those of whom you’re trying to influence. Take, for example, the story of King Louis XI of France, a staunch believer in astrology.

When a courtier correctly predicted the death of a member of his imperial household, the king worried that having such a powerful seer in his court might pose a threat to his authority. He summoned the man, planning to have him thrown to his death from a window ledge. But first he addressed him gravely. “You claim to be able to interpret the heavens,” King Louis said, “and to know the fate of others So tell me: What fate will befall you, and how long do you have to live?”

The oracle thought carefully for a moment. Then he smiled. “I shall meet my end,” he replied, “just three days before Your Majesty meets his.” A perfect, if apocryphal, example of the courtier using perceived self-interest on the king’s part as a way to save his own life.

Source of Information : Scientific American Mind March-April 2010

The Power to Persuade - Simplicity

Written by Science Knowledge on 1:54 AM

“Easy to swallow, easy to follow” is the brain’s heuristic for influence. This is one reason why the world’s great orators have always spoken in threes. Julius Caesar’s “veni, vidi, vici,” for example. Or Abraham Lincoln in the Gettysburg Address: “we cannot dedicate, we cannot consecrate, we cannot hallow this ground.”

This device, known as the tricolon, is among a number of rhetorical secrets first identified by the speakers of the ancient world, classical orators such as Cicero, Demosthenes and Socrates (who themselves form a tricolon). Its magic lies in its efficiency: a third word not only gives confirmation and completes a point, it is also economical, constituting the earliest stage at which a possible connection, implied by the first two words, may be substantiated. More than three, and you risk going on and on. Fewer than three, and your argument lands prematurely.

The bottom line couldn’t be any clearer: the shorter, sharper, simpler the message—tricolon again—the more amenable we are to its content. Imagine I were to hand you a recipe for Japanese rolls—and that it was printed in this typeface (Times New Roman, 12 point). Next, imagine I were to ask you to estimate how long it would take you to prepare the recipe. And then, how inclined you were to do so.

Question: Do you think you would rate the dish as being easier to cook if it were printed in this typeface (Brush, 12 point)? Or do you think that the typeface would make little difference to your judgment? Psychologists Hyunjin Song and Norbert Schwarz of the University of Michigan at Ann Arbor put exactly this question to a group of college students in 2008. And guess what? The fussier the typeface, the more difficult the students judged the recipe. And what’s more, the less likely they were to attempt it. Even though the recipes were exactly the same in both cases, the students walked into a classic cognitive ambush: they confused the facility with which they took in information with the resources required to comply with it. Result? The group gave Brush the brush-off.

Source of Information : Scientific American Mind March-April 2010


About Me

In its broadest sense, science (from the Latin scientia, meaning "knowledge") refers to any systematic knowledge or practice. In its more usual restricted sense, science refers to a system of acquiring knowledge based on scientific method, as well as to the organized body of knowledge gained through such research.

Fields of science are commonly classified along two major lines: natural sciences, which study natural phenomena (including biological life), and social sciences, which study human behavior and societies. These groupings are empirical sciences, which means the knowledge must be based on observable phenomena and capable of being experimented for its validity by other researchers working under the same conditions.


You are welcome to contact me and leave your comments in my Blog.

Science Knowledge

Want to subscribe?

Science Knowledge

Grab this Headline Animator

Enter your email address:

Delivered by FeedBurner