DPABISurf statistical threshold

Dear DPABI community,

I ran some statistical analysis on surface data generated by DPABIsurf. However, I cannot figure out how to threshold my resulting T-map when viewing it in DPABISurf viewer as it is possible in volumetric analysis (e.g. select GRF, determine cluster threshold, voxel threshold etc.). Am I missing something?

Thanks a lot!

Best wishes

Julian