- FNIR
fNIR stands for functional
near-infrared imaging. fNIR is a spectroscopic neuro-imaging method for measuring the level of neuronal activity in thebrain . The method is based on neuro-vascular coupling, that is, the relationship between metabolic activity and oxygen level (oxygenated hemoglobin) in feeding blood vessels.There are three types of fNIR:
*CW - continuous wave - In this method, infrared light shines at the same intensity level during the measurement period. The detected signal is lower intensity static signal (dc valued)
*FD - frequency domain - In this method, input signal is modulated sinusoid at some frequency and detected output signal has changes in amplitude and phase.
*TR - time resolved - In time resolve spectroscopy, a very short pulse is introduced to measured and the pulse length is usually on the order of picoseconds. The detected signal is usually a longer signal and has a decay time.
*fNIR device was first invented by Dr.
Britton Chance of theUniversity of Pennsylvania . Current cwFNIR devices have improved with the advent of electronics. [http://www.redorbit.com/news/health/107194/athome_breast_cancer_detector_tested/index.html] At the Optical Brain Imaging Lab ofDrexel University , in collaboration with Penn, battery operated, wireless cwfNIR devices have been developed. [http://www.newswise.com/articles/view/518934/]External links
* [http://www.uphs.upenn.edu/biocbiop/faculty/pages/chance.html Lab of BC at University of Pennsylvania]
* [http://www.biomed.drexel.edu/fnir/ Optical Brain Imaging Lab at Drexel University]See also
*
Near infrared spectroscopy
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