Health & Wellness
If you ever argued with your mother when she told you to get some sleep after studying for an exam instead of pulling an all-nighter, you owe her an apology, because it turns out she's right. And now, scientists are beginning to understand why.
© Marcos Frank, Ph.D
The world as the brain sees it. Optical "polar" maps of the visual cortex are generated by measuring micro-changes in blood oxygenation (left panel). If vision is blocked in an eye (the right eye in this example) during a critical period of development, neurons no longer respond to input from the deprived eye pathway (indicated by a loss of color in the right panel).
In research published this week in Neuron
, Marcos Frank, PhD, Assistant Professor of Neuroscience, at the University of Pennsylvania School of Medicine, postdoctoral researcher Sara Aton, PhD, and colleagues describe for the first time how cellular changes in the sleeping brain promote the formation of memories.
"This is the first real direct insight into how the brain, on a cellular level, changes the strength of its connections during sleep," Frank says.
The findings, says Frank, reveal that the brain during sleep is fundamentally different from the brain during wakefulness.
Studies show how adult brains can be rewired back to a younger state.
The pirate look is a time-honored way to fix children's "lazy eye": the patch over the good eye forces the weak one to work, thereby preventing its deterioration. Playing video games helps, too. The neural cells corresponding to both eyes then learn to fire in synchrony so that the brain wires itself for the stereo vision required for depth perception. Left untreated past a critical age, lazy eye, or amblyopia, can result in permanently impaired vision. New studies are now showing that this condition, which affects up to 5 percent of the population, could be repaired even past the critical phase.
What is more, amblyopia may provide insights into brain plasticity that could help treat a variety of other disorders related to faulty wiring, including schizophrenia, epilepsy, autism, anxiety and addiction. These ailments "are not neurodegenerative diseases that destroy part of the neural circuitry," notes Takao Hensch, a Harvard Medical School researcher. So if the defective circuits "could be stimulated in the right way, the brain could develop normally."
The nonprofit environmental law firm Earthjustice has sued the Environmental Protection Agency (EPA) for failing to properly take into account the health and ecological risks of approved pesticides.
"There are several pesticides on the market that pose extreme risks to human health - through the water, air and food," said Earthjustice attorney Joshua Osborne-Klein. "Our lawsuits say that the EPA has not fully assessed these risks."
Of particular concern is the tendency of pesticides and other agricultural chemicals to end up in the groundwater, via air, soil and surface water contamination. The EPA has warned that groundwater is "highly susceptible to contamination from septic tanks, agricultural runoff, highway de-icing, landfills, and pipe leaks."
The new $800 billion economic stimulus bill contains some striking new "Big Brother" health care language that should give pause to all freedom-loving Americans. For starters, the bill requires the electronic tracking of the medical records of all Americans. All your private medical data will be stored in a government database, including your history of disease, pharmaceutical treatments, surgeries and even emergency room visits.
How would you like the government knowing all the details about your drug rehab? Or alcoholism treatments? Abortion? Sexually-transmitted disease diagnosis? Pregnancy status? Blood test results?
But it gets even more interesting than that: Under the new provisions found in the bill, all U.S. doctors will now be stripped of autonomy and forced to follow the medical treatment guidelines dictated by the government.
Young drivers who use cell phones at the wheel drive like the elderly - with slower reaction times and an increased risk of accidents - a new study shows. And what's more, hands-free phones are no safer than handheld ones, scientists behind the study say.
"If you put a 20-year-old driver behind the wheel with a cell phone, their reaction times are the same as a 70-year-old driver who is not using a cell phone," said David Strayer, a University of Utah psychology professor and principal author of the study.
"For five years or so we've been interested in what happens when someone picks up a cell phone and starts to drive," Strayer said.
One thing that appears to happen is that phone-using drivers of all ages have significantly diminished reaction times. They are slower to hit the brakes and more likely to get into accidents.
Subjects took "freeway drives" in a simulator, using a hands-free mobile phone for half of the drive.
Every day we are confronted with positive and negative statements. By combining the new, incoming information with what we already know, we are usually able to figure out if the statement is true or false. Previous research has suggested that including negative words, such as "not," in the middle of a sentence can throw off our brains and make it more difficult to understand.
Psychologists Mante S. Nieuwland and Gina R. Kuperberg from Tufts University investigated how different types of negative statements are processed in the brain. In this study, the researchers measured event related potential responses (ERPs) while participants read statements containing critical, mid-sentence words that made the statement true or false. An ERP is an electrical brain response, as measured at the scalp with electrodes, that is directly related to something that is seen or heard. ERP studies have been used to provide us with information about how language is initially processed in the brain before any noticeable behavior occurs. Previous studies have shown that when reading affirmative statements, large ERPs occur at the words which make the statement false.
In this study, participants read statements that were either pragmatically licensed or pragmatically unlicensed. Pragmatically licensed statements are informative and sound natural. For example, "In moderation, drinking red wine isn't bad for your health" is a pragmatically licensed statement. Pragmatically unlicensed statements, on the other hand, are unnatural and not helpful. An example of this type of statement would be, "Vitamins and proteins aren't very bad for your health." This statement is unlicensed because including the negative word "aren't" implies that vitamins and proteins may be bad for your health, which we know is not true. In this case, the negative word makes the statement trivial and not very useful.
To contain U.S. disease outbreaks spread by prairie dogs to ferrets, it's Kazakhstan's giant gerbils to the rescue.
Plague conjures images of Gothic horror - rough wooden carts piled high with pestilent bodies - but it is more than a medieval memory. The disease, caused by the bacterium Yersinia pestis, kills several hundred people every year by attacking the lungs, lymph nodes or blood. Less obviously, plague also ravages wildlife around the world.
Introduced to the U.S. a century ago, it is creeping into the upper Midwest, wiping out prairie dogs and threatening the black-footed ferret, one of North America's rarest species. Confined to rural regions, the disease so far is not a major threat to people - only a few Americans die from it annually. But things could change if the bacterium spreads to urban-loving rodents such as rats. Now some researchers think that another species could provide the information needed to contain plague's spread in the U.S.: the giant gerbils of Kazakhstan.
Inhabitants of the vast steppes of Central Asia, the gerbils grow to one foot in length. They are natural hosts for Yersinia, and many researchers believe that the plague bacterium, carried by fleas hitching rides on the Mongols centuries ago, spread from these gerbils. Until World War II, plague killed scores of people every year in Kazakhstan. "Whole villages were being wiped out," recounts Stephen Davis, an Australian researcher who recently joined Yale University's School of Public Health.
Results of a recent study conducted by researchers at Wake Forest University Baptist Medical Center and colleagues show that cognitive functioning abilities drop as average blood sugar levels rise in people with type 2 diabetes.
The study appears in this month's issue of Diabetes Care.
The ongoing Memory in Diabetes (MIND) study, a sub-study of the Action to Control Cardiovascular Risk in Diabetes Trial (ACCORD), found a statistically significant inverse relationship between A1C levels (average blood glucose levels over a period of two to three months) and subjects' scores on four cognitive tests. No association, however, was found between daily blood glucose levels (measured by the fasting plasma glucose test) and test scores.
For the study, researchers at 52 of the 77 ACCORD sites throughout the United States and Canada administered a 30-minute battery of cognitive tests to nearly 3,000 individuals ages 55 years and older.
Many children's vitamins contain so few nutrients in such low doses that they are no healthier than candy, according to a study conducted by researchers from the Center for Nutritional Education in conjunction with www.supplementscompared.com.
"Parents need to be aware that a lot of the supplements for children contain only a very small number of vitamins," researcher Kate Neil said. "They look like sweets, taste like sweets and in a sense they are sweets."
Parents would be better off spending money to provide a healthier diet than buying many of the supplements, the researchers said.
The ability to empathize with others is partially determined by genes, according to new research on mice from the University of Wisconsin-Madison and Oregon Health and Science University (OHSU).
In the study, a highly social strain of mice learned to associate a sound played in a specific cage with something negative simply by hearing a mouse in that cage respond with squeaks of distress. A genetically different mouse strain with fewer social tendencies did not learn any connection between the cues and the other mouse's distress, showing that the ability to identify and act on another's emotions may have a genetic basis. The new research will publish Wednesday, Feb. 11, in the Public Library of Science ONE
journal at here
Like humans, mice can automatically sense and respond to others' positive and negative emotions, such as excitement, fear or anger. Understanding empathy in mice may lead to important discoveries about the social interaction deficits seen in many human psychosocial disorders, including autism, schizophrenia, depression and addiction, the researchers say. For example, nonverbal social cues are frequently used to identify early signs of autism in very young children.