fNIRS with a Gowerlabs NTS system<unk>  (fNIRS) is an optical brain monitoring technique which uses<unk><unk><unk>  for the purpose of<unk>  neuroimaging. Using fNIRS, brain activity is measured by using<unk><unk>  light to estimate cortical hemodynamic activity which occur in response to neural activity. Alongside EEG, fNIRS is one of the most common non-invasive neuroimaging techniques which can be used in portable contexts. The signal is often compared with the BOLD signal measured by fMRI and is capable of measuring changes both in oxy- and deoxyhemoglobin concentration, but can only measure from regions<unk>  the cortical surface. fNIRS may also be referred to as Optical Topography (OT) and is sometimes referred to simply as NIRS.
Functional near-infrared spectroscopy
Iatrochemistry
Hemoximetry
Intravascular fluorescence
Spectral imaging 
Perfusion scanning
Photoplethysmogram
Diffuse optical imaging