Enhancing the Detection of BOLD Signal in fMRI by Reducing the Partial Volume Effect

Figure 7

The activation maps at the frontal eye fields (FEF) in 6 subjects. In (a), the original maps are shown at the top, the interpolated maps (𝑘-space) are shown at the middle, and the interpolated maps (magnitude) are shown at the bottom. Two apparently connected activated voxels in the original map are separated in the interpolated map (large blue circle). A single-voxel activation in the original maps can be a single-voxel activation (small blue circle) or a group of 6 activated voxels (small green circle) in subjects 1 and 2 in the interpolated map. In subject 3, the activated voxels form an enclosed loop in the original map but not in the interpolated map (large green circle). Similar results were also seen in the interpolated maps obtained with magnitude VSI. (b) shows the interpolated map in a slice from subject 6, at which the region of FEF is indicated by a green box.