If you are depressed, or schizophrenic or have Alzheimer's, scientists say you probably have a shrunken hippocampus. The good news: a drug that just entered human trials promises to re-grow that part of the brain.
The National Institutes of Health has halted all new funding for studies using chimpanzees, humans' closest evolutionary relatives, as scientific models for humans.
The first European embryonic stem cell therapy in humans is about to start in London. Surgeons will insert the controversial cells into the eyes of 12 patients suffering from Stargardt's macular dystrophy, a major cause of blindness in young people.