SCIENCE: Cheap Magnetic Helmet Detects Some Kinds of Brain Damage. “A helmet that sends a magnetic field through the wearer’s head might someday offer a quick way to reveal whether the brain is swelling or bleeding as the result of an injury. In a prototype of the helmet, a small halo-like coil generates a magnetic field above a person’s head; another coil, just above the ears, detects the magnetic field induced in the volunteer’s brain. Because liquid such as blood affects the magnetic field’s phase, the team behind the device was able to distinguish eight brain-injured patients from 46 healthy volunteers in a pilot study, they report in the journal PLOS One.”