Talk of the Nation

Amyloid plaques and tangles of protein in the brain are two of the key signs of the form of dementia known as Alzheimer's disease. In new work reported in the journal PLOS One, researchers tracked the spread of tangles of tau protein from neuron to neuron in the brains of mice. Study co-author Karen Duff of the Columbia University Medical Center discusses the findings.

NASA's iconic images of Earth from space date back to the late 1960s--with snapshots taken by Apollo astronauts. The modern "blue marble" images are captured by machines and they're not photos. They're datasets collected by instruments aboard satellites and then translated into imagery on the ground.

In That's Disgusting: Unraveling the Mysteries of Repulsion, psychologist Rachel Herz discusses the origins of disgust — what she calls the 'instinct that's learned' — and why humans turn up their noses at smelly feet but devour expensive cheeses cultured with some of the very same stinky bacteria.

Unmanned Aerial Vehicles (UAVs) are replacing boots on the ground in some wars. Commercially, UAVs are being used for things like crop-dusting and flood mapping. Experts discuss advances in drone technology and how to address legal and privacy concerns that stem from their use.

Reporting in PLoS Biology, researchers write that they were able to correlate words a person was hearing to specific electrical activity in the brain. Study co-author neuroscientist Robert Knight discusses future applications of this research and concerns that it amounts to mental wiretapping.