ABSTRACT
The portable nature of optical imaging technology opens the door to high-resolution bedside imaging of functional brain health. Brain imaging via positron emission tomography (PET), functional magnetic resonance imaging (fMRI), and, more recently, diffuse optical tomography have illuminated many aspects of the biological basis of human behavior. Both fMRI and optical imaging utilize changes in blood flow and oxygenation concentration to infer neuronal activity. Optical neuroimaging provides a unique alternative human brain mapping technique for situations in which either fMRI or PET is contraindicated. Solutions to the diffusion equation for tissues with an arbitrary geometry and spatially varying optical properties can be calculated using a number of publicly available packages such as NIRFAST or TOAST++ that utilize finite element modeling. A crucial design detail, regardless of whether fibers are used or if the optical components are on the head, is to comb through the participant’s hair to gain unimpeded access to the scalp.
