Event Related Optical Signal

Event Related Optical Signal (EROS) is a brain-scanning technique which uses infrared light through optical fibers to measure changes in optical properties of active areas of the cerebral cortex. It can pinpoint activity in the brain within millimeters (spatially) and within milliseconds (temporally). Its biggest downside is the inability to detect activity more than a few centimeters deep, but it is a new, relatively inexpensive technique that is not invasive to the test subject. It was developed at the University of Illinois at Urbana-Champaign.