Near Infrared Imaging and Spectroscopy for Brain Activity Monitoring

The first demonstration that near infrared (NIR) light can be used to monitor the state of cortical tissues noninvasively through the skull was presented by Jobsis in 1977 [53]. About a decade later, researchers started looking at the potential use of NIR spectroscopy for functional brain activity monitoring. Early studies began with simple motor and sensory tasks demonstrating the feasibility of the technology for noninvasively assessing the state of cerebral activity in a localized area. More recent studies have attempted to monitor more complex cognitive tasks such as warfare management [48] and aircraft landing simulations [102]. In this chapter, the research surrounding the application of NIR imaging and spectroscopy to noninvasive monitoring of functional brain activity is reviewed. A comprehensive review of equipment technologies, mathematical models, and past studies is given with some emphasis on the techology’s potential in security and defense applications.