Curiosity plays a big part in preschoolers' lives. A new study that explored why young children ask so many "why" questions concludes that children are motivated by a desire for explanation. The study, by researchers at the University of Michigan, appears in the November/December 2009 issue of the journal Child Development.

The researchers carried out two studies of 2- to 5-year-olds, focusing on their "how" and "why" questions, as well as their requests for explanatory information, and looking carefully at the children's reactions to the answers they received from adults. In the first study, the researchers examined longitudinal transcripts of six children's everyday conversations with parents, siblings, and visitors at home from ages 2 to 4. In the second study, they looked at the laboratory-based conversations of 42 preschoolers, using toys, storybooks, and videos to prompt the children, ages 3 to 5, to ask questions.

By looking at how the children reacted to the answers they received to their questions, the researchers found that children seem to be more satisfied when they receive an explanatory answer than when they do not. In both studies, when preschoolers got an explanation, they seemed satisfied (they agreed or asked a new follow-up question). But when they got answers that weren't explanations, they seemed dissatisfied and were more likely to repeat their original question or provide an alternative explanation.

"Examining conversational exchanges, and in particular children's reactions to the different types of information they get from adults in response to their own requests, confirms that young children are motivated to actively seek explanations," according to the researchers. "They use specific conversational strategies to obtain that information. When preschoolers ask 'why' questions, they're not merely trying to prolong conversation, they're trying to get to the bottom of things."

The moderate sample size means that the study cannot be generalized to all children, but the research clearly suggests that by age 2, children contribute actively to the process of learning about the world around them.

Patients with coronary heart disease who practiced the stress-reducing Transcendental Meditation® technique had nearly 50 percent lower rates of heart attack, stroke, and death compared to nonmeditating controls, according to the results of a first-ever study presented during the annual meeting of the American Heart Association in Orlando, Fla., on 16 Nov. 2009.

The trial was sponsored by a $3.8 million grant from the National Institutes of Health–National Heart, Lung, and Blood Institute, and was conducted at The Medical College of Wisconsin in Milwaukee in collaboration with the Institute for Natural Medicine and Prevention at Maharishi University of Management in Fairfield, Iowa.

The nine-year, randomized control trial followed 201 African American men and women, average age 59 years, with narrowing of arteries in their hearts who were randomly assigned to either practice the stress-reducing Transcendental Meditation technique or to participate in a control group which received health education classes in traditional risk factors, including dietary modification and exercise. All participants continued standard medications and other usual medical care.

The study found:

• A 47% reduction in the combination of death, heart attacks, and strokes in the participants
  
• Clinically significant (5 mm Hg average) reduction in blood pressure associated with decrease in clinical events
  
• Significant reductions in psychological stress in the high-stress subgroup

According to Robert Schneider, M.D., FACC, lead author and director of the Center for Natural Medicine and Prevention, "Previous research on Transcendental Meditation has shown reductions in blood pressure, psychological stress, and other risk factors for heart disease, irrespective of ethnicity. But this is the first controlled clinical trial to show that long-term practice of this particular stress reduction program reduces the incidence of clinical cardiovascular events, that is heart attacks, strokes and mortality."

"This study is an example of the contribution of a lifestyle intervention—stress management—to the prevention of cardiovascular disease in high-risk patients," said Theodore Kotchen, M.D., co-author of the study, professor of medicine, and associate dean for clinical research at the Medical College. Other investigators at the Milwaukee site included Drs. Jane Kotchen and Clarence Grim.

Dr. Schneider said that the effect of Transcendental Meditation in the trial was like adding a class of newly discovered medications for the prevention of heart disease. "In this case, the new medications are derived from the body's own internal pharmacy stimulated by the Transcendental Meditation practice," he said.

Texting, Talking and Other Uses of the Cell Phone Behind the Wheel
(by Mary Madden, Senior Research Specialist and Amanda Lenhart, Senior Research Specialist, Pew Internet & American Life Project)

Overview of Study: Over the summer of 2009, the Pew Research Center's Internet & American Life Project conducted a survey of 800 teens ages 12-17 asking about their experiences with cell phone use in cars. All of the teens in our survey were asked about their experiences as passengers, and if they were age 16 or older and have a cell phone, they were also asked about their own actions behind the wheel including both talking and text messaging. Additionally, the Pew Internet Project and the University of Michigan conducted nine focus groups with teens ages 12-18 between June and October 2009 where the topic of driving and mobile phones was addressed. The following are the major findings from the survey and focus groups:

• 75% of all American teens ages 12-17 own a cell phone, and 66% use their phones to send or receive text messages.
  
• Older teens are more likely than younger teens to have cell phones and use text messaging; 82% of teens ages 16-17 have a cell phone and 76% of that cohort are cell phone texters.
  
• One in three (34%) texting teens ages 16-17 say they have texted while driving. That translates into 26% of all American teens ages 16-17.
  
• Half (52%) of cell-owning teens ages 16-17 say they have talked on a cell phone while driving. That translates into 43% of all American teens ages 16-17.
  
• 48% of all teens ages 12-17 say they have been in a car when the driver was texting.
  
• 40% say they have been in a car when the driver used a cell phone in a way that put themselves or others in danger.

[full report available here (.pdf)]

The first ever large-scale, longitudinal study of ketamine users has been published online today in the journal Addiction. With Ketamine (K, Special K) use increasing faster than any other drug in the UK (British Crime Survey, 2008) this research showing the consequences of repeated ketamine use provides valuable information for users and addiction professionals alike.

For the study, researchers from University College London followed 150 people over a year to see if changes in their ketamine use could predict changes in their psychological well-being, memory and concentration. Of these 150 people, 30 were taking large quantities of the drug nearly every day, 30 were taking it 'recreationally' (once or twice a month), 30 were former users, 30 used illicit drugs apart from ketamine and 30 did not use any illicit drugs.

The authors found that the heavy ketamine users were impaired on several measures, including verbal memory. Short term memory and visual memory in this group decreased over the year as ketamine use increased. These individuals also performed more poorly overall on verbal memory, displaying symptoms such as forgetfulness and experiencing difficulty recalling conversations and people's names.

The amount of increase in ketamine use over the course of one year was also a source of concern. Hair analysis showed that ketamine levels among recreational users doubled at follow-up compared to initial testing, a pattern seen with other addictive drugs. Ketamine levels in the frequent using group did not change across the year, but this group was already using up to ten grams per day at initial testing.

Interestingly, the recreational ketamine users and ex-ketamine users did not differ from non-drug-taking controls on memory, attention and measures of psychological well-being, suggesting that occasional ketamine use does not lead to prolonged harms to cognitive function and that any damage may be reversed when people quit using the drug. However, all groups of ketamine users showed evidence of unusual beliefs or mild 'delusions', with these being greatest in the frequent users and least in ex-users (i.e. it appeared dependent on the amount of the drug used). It is not clear to what extent this is a pre-existing difference in ketamine users, something that develops from using the drug or a mixture of both.

Says lead author Dr. Celia Morgan: "These findings have implications for the growing number of ketamine users in the UK as well as addiction professionals who may encounter increasing numbers of ketamine dependent users. These findings suggest these frequent ketamine users will be impaired, albeit transiently, in a variety of psychological domains."

Two new studies of pedestrian safety found that using a cell phone while hoofing it can endanger one's health. Older pedestrians, in particular, are impaired when crossing a busy (simulated) street while speaking on a mobile phone, the researchers found.

The studies, in which participants crossed a virtual street while talking on the phone or listening to music, found that the music-listeners were able to navigate traffic as well as the average unencumbered pedestrian. Users of hands-free cell phones, however, took longer to cross the same street under the same conditions and were more likely to get run over.

Older cell-phone users, especially those unsteady on their feet to begin with, were even more likely to become traffic casualties. "Many people assume that walking is so automatic that really nothing will get in the way," said University of Illinois psychology professor Art Kramer, who led the research with psychology professor Jason McCarley and postdoctoral researcher Mark Neider. "And walking is pretty automatic, but actually walking in environments that have lots of obstacles is perhaps not as automatic as one might think."

The first study, in the journal Accident Analysis and Prevention, found that college-age adults who were talking on a cell phone took 25 percent longer to cross the street than their peers who were not on the phone. They were also more likely to fail to cross the street in the 30 seconds allotted for the task, even though their peers were able to do so.

Each participant walked on a manual treadmill in a virtual environment, meaning that each encountered the exact same conditions – the same number and speed of cars, for example – as their peers. The second (and not yet published) study gave adults age 60 and above the same tasks, and included some participants who had a history of falling. The differences between those on and off the phone were even more striking in the older group, Kramer said. "Older adults on the phone got run over about 15 percent more often" than those not on the phone, he said, and those with a history of falling fared even worse. "So walking and talking on the phone while old, especially, appears to be dangerous," he said.

Most of the linguistic functions in humans are controlled by the left cerebral hemisphere. A study of captive chimpanzees at the Yerkes National Primate Research Center (Atlanta, Georgia), reported in the January 2010 issue of Elsevier's Cortex, suggests that this "hemispheric lateralization" for language may have its evolutionary roots in the gestural communication of our common ancestors. A large majority of the chimpanzees in the study showed a significant bias towards right-handed gestures when communicating, which may reflect a similar dominance of the left hemisphere for communication in chimpanzees as that seen for language functions in humans.

A team of researchers, supervised by Prof. William D. Hopkins of Agnes Scott College (Decatur, Georgia), studied hand-use in 70 captive chimpanzees over a period of 10 months, recording a variety of communicative gestures specific to chimpanzees. These included 'arm threat', 'extend arm' or 'hand-slap' gestures produced in different social contexts, such as attention-getting interactions, shared excitation, threat, aggression, greeting, reconciliation or invitations for grooming or for play. The gestures were directed at the human observers, as well as toward other chimpanzees.

"The degree of predominance of the right hand for gestures is one of the most pronounced we have ever found in chimpanzees in comparison to other non-communicative manual actions. We already found such manual biases in this species for pointing gestures exclusively directed to humans. These additional data clearly showed that right-handedness for gestures is not specifically associated to interactions with humans, but generalizes to intraspecific communication", notes Prof. Hopkins.

The French co-authors, Dr. Adrien Meguerditchian and Prof. Jacques Vauclair, from the Aix-Marseille University (Aix-en-Provence, France), also point out that "this finding provides additional support to the idea that speech evolved initially from a gestural communicative system in our ancestors. Moreover, gestural communication in apes shares some key features with human language, such as intentionality, referential properties and flexibility of learning and use".

'The results of our research should encourage psychiatric investigation into using cannabinoids in post-traumatic stress patients,' says researcher Dr. Irit Akirav of the University of Haifa

Use of cannabinoids (marijuana) could assist in the treatment of post-traumatic stress disorder patients. This is exposed in a recent study carried out at the Learning and Memory Lab in the University of Haifa's Department of Psychology. The study, carried out by research student Eti Ganon-Elazar under the supervision of Dr. Irit Akirav, was published in the prestigious Journal of Neuroscience.

In most cases, the result of experiencing a traumatic event – a car accident or terror attack – is the appearance of medical and psychological symptoms that affect various functions, but which pass. However, some 10%-30% of people who experience a traumatic event develop post-traumatic stress disorder, a condition in which the patient continues to suffer stress symptoms for months and even years after the traumatic event. Symptoms include reawakened trauma, avoidance of anything that could recall the trauma, and psychological and physiological disturbances. One of the problems in the course of treating trauma patients is that a person is frequently exposed to additional stress, which hinders the patient's overcoming the trauma.

The present study, carried out by Dr. Akirav and research student Eti Ganon-Elazar, aimed to examine the efficiency of cannabinoids as a medical treatment for coping with post-traumatic stress. The researchers used a synthetic form of marijuana, which has similar properties to the natural plant, and they chose to use a rat model, which presents similar physiological responses to stress to that of humans.

The first stage of the research examined how long it took for the rats to overcome a traumatic experience, without any intervention. A cell colored white on one side and black on the other was prepared. The rats were placed in the white area, and as soon as they moved over to the black area, which they prefer, they received a light electric shock. Each day they were brought to the cell and placed back in the white area. Immediately following exposure to the traumatic experience, the rats would not move to the black area voluntarily, but a few days later after not receiving further electric shocks in the black area, they learned that it is safe again and moved there without hesitation.

Next, the researchers introduced an element of stress. A second group of rats were placed on a small, elevated platform after receiving the electric shock, which added stress to the traumatic experience. These rats abstained from returning to the black area in the cell for much longer, which shows that the exposure to additional stress does indeed hinder the process of overcoming trauma.

The third stage of the research examined yet another group of rats. These were exposed to the traumatic and additional stress events, but just before being elevated on the platform received an injection of synthetic marijuana in the amygdala area of the brain – a specific area known to be connected to emotive memory. These rats agreed to enter the black area after the same amount of time as the first group – showing that the synthetic marijuana cancelled out the symptoms of stress. Refining the results of this study, the researchers then administered marijuana injections at different points in time on additional groups of rats, and found that regardless of when exactly the injection was administered, it prevented the surfacing of stress symptoms.

Dr. Akirav and Ganon-Elazar also examined hormonal changes in the course of the experiment and found that synthetic marijuana prevents increased release of the stress hormone that the body produces in response to stress.

According to Dr. Akirav, the results of this study show that cannabinoids can play an important role in stress-related disorders. "The results of our research should encourage psychiatric investigation into the use of cannabinoids in post-traumatic stress patients," she concludes.

The "chocolate cure" for emotional stress is getting new support from a clinical trial published online in ACS' Journal of Proteome Research. It found that eating about an ounce and a half of dark chocolate a day for two weeks reduced levels of stress hormones in the bodies of people feeling highly stressed. Everyone's favorite treat also partially corrected other stress-related biochemical imbalances.

Sunil Kochhar and colleagues note growing scientific evidence that antioxidants and other beneficial substances in dark chocolate may reduce risk factors for heart disease and other physical conditions. Studies also suggest that chocolate may ease emotional stress. Until now, however, there was little evidence from research in humans on exactly how chocolate might have those stress-busting effects.

In the study, scientists identified reductions in stress hormones and other stress-related biochemical changes in volunteers who rated themselves as highly stressed and ate dark chocolate for two weeks. "The study provides strong evidence that a daily consumption of 40 grams [1.4 ounces] during a period of 2 weeks is sufficient to modify the metabolism of healthy human volunteers," the scientists say.

See also: Dark Chocolate: Half a Bar Per Week to Keep at Bay the Risk of Heart Attack posted in Sept 2008


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