Functional Near Infrared Spectroscopy

In this document, I briefly introduce the theory behind the measurement of haemoglobin (Hb) concentration in the human frontal cortex by functional near infrared spectroscopy (fNIRS) and I apply it to a consumer-grade wearable (Athena S Muse). In particular, I describe a script in R programming language that derives resting-state relative concentrations of both oxygenated and non-oxygenated Hb from five-minute recordings. I briefly discuss the results of my 9-month recordings and their correlation with a subjective measure of cognitive functioning.