Abstract

The cross talk between change in concentration of oxy- and deoxy-haemoglobin in brain activity measurement with near-infrared spectroscopy is investigated. The cross talk in the results calculated from changes in intensity of detected light at various wavelength pairs is obtained by Monte Carlo simulation. The 780/830-nm wavelength pair, which is normally used for conventional NIRS instruments, causes considerable cross talk from oxy- to deoxy-haemoglobin. The optimal wavelength range for pairing with 830 nm to minimise the cross talk is from 690 to 750 nm.

© 2004 Optical Society of America