afni.nimh.nih.gov

> Is there a recommended cluster defining threshold to use? Is p = 0.01 standard?

Do you mean the voxel-wise (or uncorrected) p-value? If so, anything goes. In general it's a tradeoff: a lower voxel-wise p-value requires larger minimum cluster size, and a higher voxel-wise p-value is associated with smaller minimum cluster size. So you may have to find a sweet spot yourself based on your data.

Gang