Effects of Transverse Relaxation on Functional Connectivity of Default Mode Network
نویسندگان
چکیده
INTRODUCTION Low-frequency (<0.1Hz) spontaneous fluctuations in resting-state fMRI have been used to study functional connectivity in brain networks (1, 2). However, the underlying mechanism and contrast-to-noise ratio (CNR) of the connectivity remain inconclusive (3). While the CNR of stimulation-induced brain activation has been well studied, much less is known about the optimization of functional connectivity (4). In the current work, we used a multiple gradient-echo sequence to investigate the transverse relaxation (T2 ) effects on the spatial pattern, connectivity strength and spectral power of functional connectivity in the default mode (DM) network at 3T.
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