Sojung, it's up to you which method you want to pursue.
> functional connectivity is the correlation of BOLD signals between the ROI and the whole brain. The averaged BOLD
> time series of all voxels in the ROI is compared against each voxel in the brain, and clusters of voxels that correlate
> highly enough to be significant. This would be a Seed-to-Voxel analysis.
Your definition is still pretty vague to me. Correlation under one particular task or in general? I'm not so sure in what sense we could help you in specifics.
Gang