- Non-invasive functional near infrared (fNIR) imaging techniques use infrared light to detect changes in blood volume and oxygen levels during brain activity. fNIR is being studied as a possible way to examine the brain activity of individuals who are unable to undergo standard brain function imaging techniques (such as functional magnetic resonance imaging, or fMRI). For instance, war veterans who have iron shrapnel in the body are not able to have fMRI scans, and very young children or children with autism and related disorders are often not able or willing to cooperate long enough in the MRI environment to allow full imaging studies to take place. Researchers are interested in comparing the results of fNIR and fMRI performed on healthy volunteers to determine if fNIR produces similarly accurate results.