  This study proposes an approach to estimate the functional localization and
connectivity from CBF and BOLD signals simultaneously measured by ASL (arterial
spin labeling) MRI, especially using exploratory Structural Equation Modeling
analysis. In a visual task experiment, the primary visual cortices were located
by analyzing the perfusion data. In the resting state experiment, two
structural equation models were estimated at each voxel regarding to the
sensory-motor network and default-mode network. The resulting connectivity maps
indicate that supplementary motor area has significant connections to
left/right primary motor areas, and inferior parietal lobules link
significantly with posterior cingulate cortex and medial prefrontal cortex. The
model fitting results imply that BOLD signal is more directly linked to the
underlying cause of functional connectivity than CBF signal.
