A sensor positioning system for functional near-infrared neuroimaging

Abstract

In cognitive studies using functional near-infrared (fNIR) techniques, the optical sensors are placed over the scalp of the subject. In order to document the actual sensor location, a system is needed that can measure the 3D position of an arbitrary point on the scalp with a high precision and repeatability and express sensor location in reference to the international 10-20 system for convenience. In addition, in cognitive studies using functional magnetic resonance imaging (fMRI), the source location is commonly expressed using Talairach system. In order to correlate the results from the fNIR study with that of the fMRI study, one needs to project the source location in Talairach coordinates onto a site on the scalp for the placement of the fNIR sensors. This paper reports a sensor positioning system that is designed to achieve the above goals. Some initial experimental data using this system are presented. © Springer-Verlag Berlin Heidelberg 2007.