In SPM software, using the minimum of two T maps as their
conjunction without doing this for posive and negative activations
separately! If within the same regions, the voxels are activated from
map X, but deactivated from map Y, they are NOT conjunctive, right ?
But using SPM, these voxels may be considered as conjunctive if the
minimum (negative values in this case because they are always smaller
than positives no matter how big or how small their absolute values )
are significant! Why we do not do positive and negative voxels
separately so that we just compare voxels in the same direction
(positive or negative) ??