ISS will develop a novel instrument for the non-invasive imaging of functional activation of the brain. The system will consist of novel hardware and software. The hardware will include 32 laser diode emitters, and 8 photomultiplier tube detectors. Novel features of the hardware will include a customized frequency synthesizer and a customized data acquisition card, both of which will significantly improve imaging performance over current equipment. The software will include real time video maps of multiple tissue properties (hemoglobin oxygen saturation, hemoglobin concentration, and tissue optical parameters). These maps will be generated from a variety of methods including calibrated frequency domain multiple distance (C-FDMD) method, absolute frequency domain multiple distance method, continuous wave differential path length method, and crossed source-detector (CSD) path method. This multiplicity of methods will allow maps which benefit from the special characteristics of each method, from the high quantitation of C-FDMD method to the high localization of the CSD method. The system will be tested on phantoms, and in human subjects in conjunction with functional Magnetic Resonance Imaging (fMRI). Upon completion of its design and test, the system will be the world's only commercially available research system for near infrared tissue hemoglobin dynamics imaging. PROPOSED COMMERCIAL APPLICATION: 1. Optical imaging of brain activation and localization of stimulated brain cellular aggregates; 2. Cognitive neuroscience; 3. Brain oxygenation monitoring during cardiac bypass surgery; 4. Sleep-apnea studies; 5. Attention deficit disorder investigations