As food prices rise, the costs of lower-calorie foods are rising the fastest, according to a University of Washington study appearing in the December issue of the Journal of the American Dietetic Association. As the prices of fresh fruit and vegetables and other low-calorie foods have jumped nearly 20 percent in the past two years, the UW researchers say, a nutritious diet may be moving out of the reach of some American consumers.

UW researchers Dr. Adam Drewnowski, director of the Center for Public Health Nutrition, and Dr. Pablo Monsivais, a research fellow in the center, studied food prices at grocery stores around the Seattle area in 2004. They found that the foods which are less energy-dense -- generally fresh fruits and vegetables -- are much more expensive per calorie than energy-dense foods -- such as those high in refined grains, added sugars, and added fats.

When the researchers surveyed prices again in 2006, the found that the disparity in food prices only worsened with time. Lower-calorie foods jumped in price by about 19.5 percent in that two-year period, while the prices of very calorie-rich foods stayed stable or even dropped slightly, the researchers found. The general rate of food price inflation in the United States was about 5 percent during that period, according to the U.S. Department of Labor.

"That the cost of healthful foods is outpacing inflation is a major problem," said Drewnowski. "The gap between what we say people should eat and what they can afford is becoming unacceptably wide. If grains, sugars and fats are the only affordable foods left, how are we to handle the obesity epidemic""

Research conducted by Drewnowski and others at the UW Center for Obesity Research had previously shown that per calorie food costs were much higher for fresh produce and other recommended foods than for fats and sweets. Those studies were based on prevailing food prices in the United States and in Europe.

This project was the first of its kind to track the change in prices over time not by food group, but by food quality. The Labor Department monitors food prices by tracking the cost of an average "food basket," which is calculated based on what American consumers purchase at the grocery store. However, the researchers argue, the inflation rate of the overall basket may drastically underestimate the rising cost of the healthiest foods.

The UW study looked at price inflation in foods grouped by energy density, or calories per gram of food. Energy density is one measure of food quality, since many energy-dense foods also tend to be low in nutrients. People who eat energy-dense foods may consume more calories than they need.

"We are an overfed but undernourished nation," said Drewnowski.

Drewnowski and Monsivais argue that the study provides yet another piece of evidence that obesity isn't just a personal problem -- it's an economic one.

"We need to focus on bigger-scale changes, like the farm bill or other policy measures that can address the disparity in food costs," Monsivais said.

The project was supported by the U.S. Department of Agriculture and the National Institute of Dental and Craniofacial Research in the National Institutes of Health.

Children learn by imitating adults—so much so that they will rethink how an object works if they observe an adult taking unnecessary steps when using that object, according to a Yale study today in Proceedings of the National Academy of Sciences.

“Even when you add time pressure, or warn the children not to do the unnecessary actions, they seem unable to avoid reproducing the adult’s irrelevant actions,” said Derek Lyons, doctoral candidate, developmental psychology, and first author of the study. “They have already incorporated the actions into their idea of how the object works.”

Learning by imitation occurs from the simplest preverbal communication to the most complex adult expertise. It is the basis for much of our success as a species, but the benefits are less clear in instances of “over-imitation,” where children copy behavior that is not needed, Lyons said.

It has been theorized that children over-imitate just to fit in, or out of habit. The Yale team found in this study that children follow the adults’ steps faithfully to the point where they actually change their mind about how an object functions.

The study included three-to-five-year-old children who engaged in a series of exercises. In one exercise, the children could see a dinosaur toy through a clear plastic box. The researcher used a sequence of irrelevant and relevant actions to retrieve the toy, such as tapping the lid of the jar with a feather before unscrewing the lid.

The children then were asked which actions were silly and which were not. They were praised when they pinpointed the actions that had no value in retrieving the toy. The idea was to teach the children that the adult was unreliable and that they should ignore his unnecessary actions.

Later the children watched adults retrieve a toy turtle from a box using needless steps. When asked to do the task themselves, the children over-imitated, despite their prior training to ignore irrelevant actions by the adults.

“What of all of this means,” Lyons said, “is that children’s ability to imitate can actually lead to confusion when they see an adult doing something in a disorganized or inefficient way. Watching an adult doing something wrong can make it much harder for kids to do it right.”

Columbia scientists use fMR technology, find brain changes when viewing violent media

Violence is a frequent occurrence in television shows and movies, but can watching it make you behave differently? Although research has shown some correlation between exposure to media violence and real-life violent behavior, there has been little direct neuroscientific support for this theory until now.

Researchers at Columbia University Medical Center’s Functional Magnetic Resonance Imaging (fMRI) Research Center have shown that watching violent programs can cause parts of your brain that suppress aggressive behaviors to become less active.

In a paper in the Dec. 5 on-line issue of PLoS ONE (published by the Public Library of Science), Columbia scientists show that a brain network responsible for suppressing behaviors like inappropriate or unwarranted aggression (including the right lateral orbitofrontal cortex, or right ltOFC, and the amygdala) became less active after study subjects watched several short clips from popular movies depicting acts of violence. These changes could render people less able to control their own aggressive behavior. Indeed the authors found that, even among their own subjects, less activation in this network was characteristic of people reporting an above average tendency to behave aggressively. This characteristic was measured through a personality test.

A secondary finding was that after repeated viewings of violence, an area of the brain associated with planning behaviors became more active. This lends further support to the idea that exposure to violence diminishes the brain’s ability to inhibit behavior-related processing.None of these changes in brain activity occurred when subjects watched non-violent but equally engaging movies depicting scenes of horror or physical activity.

“These changes in the brain’s behavioral control circuits were specific to the repeated exposure to the violent clips,” said Joy Hirsch, Ph.D., professor of Functional Neuroradiology, Psychology, and Neuroscience and Director of the Center for fMRI at CUMC, and the PLoS ONE paper’s senior author. “Even when the level of action in the control movies was comparable, we just did not observe the same changes in brain response that we did when the subjects viewed the violent clips.”

“Depictions of violent acts have become very common in the popular media,” said Christopher Kelly, the first author on the paper and a current CUMC medical student. “Our findings demonstrate for the first time that watching media depictions of violence does influence processing in parts of the brain that control behaviors like aggression. This is an important finding, and further research should examine very closely how these changes affect real-life behavior.”