Two different forms of light have showed up in recent science headlines. Nature multi-media editor Shamini Bundell explains: light from first stars hints at dark matter. Astronomers have detected the fingerprint of light from a period known as the Cosmic Dawn, when the earliest stars were forming. If confirmed, it's an exciting discovery, on its own. It may also hold more clues about the role of dark matter. Flashing lights and pink noise may help Alzheimer's: the brain is an electrical organ,