Detection of inter-hemispheric functional connectivity in motor cortex with coherence analysis
Date
2012
Journal Title
Journal ISSN
Volume Title
Publisher
European Optical Society
Abstract
Functional near-infrared spectroscopy (fNIRS) is showing promise as an alternate method to fMRI for studying cortical function. Resting
state studies in both methods are showing functional linkages. The strength of functional connections is typically quantified by the
level of significance of the temporal synchrony between brain regions, termed resting-state functional connectivity. Coherence analysis of
resting state allows for phase insensitive and frequency specific analysis. This paper provides a detailed method for undertaking fNIRS in
combination with resting-state coherence analysis. We show that maps of inter-hemispheric resting-state functional connectivity between
the motor cortices can be reliably generated, and the frequency responses (to 50 Hz) for both oxy- and deoxyhemoglobin. Frequencies of
0-0.1 Hz provide robust data as have been shown previously. Higher frequencies (up to 5 Hz) also exhibit high coherence. Deoxyhemoglobin
also shows high coherence above 10Hz. Coherence is similar during both resting and task activated states. fNIRS allows for mapping cortical
function and, in combination with coherence analysis, allows one to study variations in frequency response.
Description
Keywords
coherence, near infrared tomograhy, functional connectivity, optics, brain, coherence analysis
Citation
VARSHNEY, V. et al. Detection of inter-hemispheric functional connectivity in motor cortex with coherence analysis. Journal of the European Optical Society - Rapid publications, Europe, v. 7, nov. 2012.