The magnetic-resonance imaging (MRI) machines that most hospitals use provide only a picture of anatomy -- revealing a mass in the brain, for example, but not its precise chemical composition. A new, much more powerful MRI scanner developed by GE Healthcare for the University of Illinois at Chicago can show concentrations of sodium, phosphorus, oxygen, and other elements in the brain. Since many neurological diseases manifest themselves as subtle biochemical changes long before anatomical changes are apparent, this scanner could enable earlier diagnosis of conditions such as Alzheimer’s disease and mental illness. Doctors and drug developers could also use it to more precisely and directly measure the effects of drugs on the brain. Thanks to 550 kilometers of superconducting wire, the scanner induces a magnetic field that’s three times stronger than even a state-of-the-art MRI machine’s, so it can pick up the weak signals from sodium and other atoms and image them with triple the resolution. While it may be many years before the new scanner can be mass-produced for hospitals, the researchers plan to begin the first human tests of the technology, pending regulatory approval, by the end of this year.