People's tendency to match their risk perceptions about policy issues with their cultural values may explain the intense disagreement over proposals to vaccinate young girls against human-papillomavirus (HPV), according to a new study in Law and Human Behavior. The study also indicates people's values shape their perceptions of expert opinion on the vaccine.

Children have a reputation for driving their parents crazy, so chances are that most people don't become parents for the health benefits. But maybe they should. According to a study conducted by researchers at Brigham Young University, raising children is associated with lower blood pressure, particularly so among women.

 Air flows in one direction as it loops through the lungs of alligators, just as it does in birds, and this breathing method may have helped the dinosaurs' ancestors dominate Earth after the planet's worst mass extinction 251 million years ago, according to scientists from the University of Utah.

Researchers at Duke University Medical Center have identified neurons in the songbird brain that convey the auditory feedback needed to learn a song. Their research, published in Neuron, lays the foundation for improving human speech, for example, in people whose auditory nerves are damaged and who must learn to speak without the benefit of hearing their own voices.

"This work is the first study to identify an auditory feedback pathway in the brain that is harnessed for learned vocal control," said Richard Mooney, Ph.D., Duke professor of neurobiology and senior author of the study. The researchers also devised an elegant way to carefully alter the activity of these neurons to prove that they interact with the motor networks that control singing.

An excess of a particular serotonin receptor in the center of the brain may explain why antidepressants fail to relieve depression symptoms for 50 percent of patients, indicates a new study published in Neuron.

The authors say the study is the first to find a causal link between receptor number and antidepressant treatment and may lead to more personalized treatment for depression, including treatments for patients who do not respond to antidepressants and ways to identify these patients before they undergo costly, and ultimately, futile therapies.

The disastrous magnitude 7.0 earthquake that triggered destruction and mounting death tolls in Haiti this week occurred in a highly complex tangle of tectonic faults near the intersection of the Caribbean and North American crustal plates, according to a geologist at the Woods Hole Oceanographic Institution (WHOI).

Jian Lin, a WHOI senior scientist in geology and geophysics, said that there were three factors that made the quake particularly devastating: First, it was centered just 10 miles southwest of the capital city, Port au Prince; second, the quake was shallow—only about 10-15 kilometers below the land's surface; third, and more importantly, many homes and buildings in the economically poor country were not built to withstand such a force and collapsed or crumbled.