Cut Up Those Cards
Forget about money burning a hole in your pocket: carrying cash rather than credit cards may help you spend less. Business researchers from New York University and the University of Maryland report that study subjects given cash to shop with spent less than those given credit. The team speculates that people are less willing to spend cash because it is the most “transparent” payment—it is easy to see how much you have spent. When the scientists asked study subjects to itemize expenses, however, they were as conservative with their credit cards as they were with their cash.   —Rachel Mahan

It’s in His Walk
Men and women have very different gaits—and viewers tend to perceive stereotypically masculine motion as approaching, whereas a feminine saunter seems to move away. As reported in September in the journal Current Biology, volunteers were asked to guess the direction of motion of point-map figures, in which the image of a walker’s body is reduced to a few dots at his or her major joints. The figures are the same from the front and back—so they could theoretically be perceived as walking either toward or away from the viewer—but volunteers perceived the swaying hips and protruding elbows of a feminine walk as moving away, and they saw neutral and masculine gaits as coming nearer. The researchers suggest that because men offer more of a threat, our ancestors may have benefited from assuming that a male figure was walking toward them—that way the observer could get ready to flee or fight. But as children, early humans may have been better off assuming that a woman, perhaps their mother, was walking away—then, they would need to follow.  —Rachel Mahan

Wisdom of the Gut
What people call intuition is really the brain picking up on subtle signals and learning how to use them, according to research in the journal Neuron in August. Over time, volunteers playing a gambling game developed a gut instinct about when to take a risky bet: they improved their winning ratio to slightly above chance, indicating they were actually responding to subliminal images embedded in the game that hinted when a bet would pay off.  —Rachel Mahan

Mental Benefits
For decades, research has suggested that mental illnesses are just as real—and devastating—as more “physical” ailments such as cancer. Now health care coverage will finally reflect this scientific understanding: in October, Congress passed a bill, 12 years in the making, requiring equal insurance coverage for mental and physical illness. Most insurance companies currently impose higher co-pays and greater restrictions on treatments for addictions, mood disorders, autism, schizophrenia and other mental illnesses. The parity law, which will go into effect for most health plans on January 1, 2010, will improve coverage for 113 million Americans, according to the National Council for Community Behavioral Healthcare. —Karen Schrock

Food Fix
Obesity is frequently framed as an addictive disorder, but scientists understand little about what first prompts the compulsion to eat. Now a study at Tufts University suggests that the impulse could be hardwired. In addicts of any type, the brain’s signaling of dopamine—a chemical involved in motivation and reward—becomes abnormal over time. The Tufts study shows, however, that rats prone to obesity are born with low dopamine levels. Eating, then, is akin to self-medication because it helps to restore the chemical to healthy levels; obesity may simply be a side effect that develops from this self-remedy over time. The findings also raise the question of whether animals born prone to obesity could be at a heightened risk for developing addictions to drugs that stimulate dopamine function, such as cocaine and amphetamines. —Melinda Wenner