A recent article in the New York Times highlights how researchers are working on a new, relatively inexpensive way to spot injuries and monitor brain diseases using magnetic sensors that can spot changes in brain waves.   This compact and portable detection device, part of the field of optical magnetometry, is constructed as a form of headgear roughly the size of a sugar cube, and works by having sensors measure changes in the brain’s magnetic field.  The device’s size, portability, and affordability allow for a wider range of applications that may someday be mass produced and used on athletes to monitor collisions and subsequent brain injuries in sports.
The compact magnetic sensors were developed by the Commerce Department’s National Institute of Standards and Technology, and they are working to offer an alternative to the costly and inflexible technology currently available, called superconducting quantum interference devices (“Squids”), which require cryogenic cooling which cannot be used at room temperature.  
Optical magnetometry has been used as an alternative to superconducting devices to monitor the magnetic fields of the heart rather than the brain.  The institute’s new compact technology, though still in prototype, has enormous potential for transforming the ways doctors and researchers can analyze the progression and status of diseases, as well as for the ability to control prosthetics using brain signals.