Imaging of infant brain using near-infrared spectroscopy: a methodological review

Abstract

NIRS (near-infrared spectroscopy) is a relatively new neuroimaging method that utilizes the attenuation of near-infrared light within tissues and can be used to measure the changes in the concentration of oxygenated and deoxygenated hemoglobin (HbO2 and HbR, respectively) in the tissue. It is a non-invasive method that does not involve strict movement or environment/facility restrictions and can be utilized in many age groups. Due to the challenges of data acquisition in infants and children that other neuroimaging methods (e.g. MRI) possess, NIRS is likely to be one of the key methods to study the developing brain.

This review critically complements previous reviews by summarizing the experimental set-up and probe characteristics while highlighting some of the most common problems encountered in NIRS studies on sensory processing (visual, auditory and tactile) in infants. We suggest some ways of making the best procedural choices in future studies to come. We hope that the review will help investigators compare and optimize their experimental set-ups.