Hi Yvonne,
Since no one more statistically savvy than me has answered as yet,
I'll poke my head out and say "no" -- FSL doesn't offer an
implementation of the "minimum statistic" implementation of
conjunction analyses. To be honest, though, there are real problems
with interpreting those statistic values, as pointed out by Tom
Nichols and colleagues. In many cases it is sufficient to use
inclusive masking. If the contrasts are truly orthogonal, then you
can reasonably multiply the p-values together to get a "conjunction"
p-value in a given voxel. For instance, if you were interested in
areas in Group 1 where A>B and masked it with Group 2's A>B (at
p<0.001 uncorrected to pick a random threshold...), then any areas at
p<0.001 in the G1 A>B contrast that are also present in G2 A>B are
unlikely to be there by chance given that the corresponding p-value
would be p<10^-6.
Personally, I wouldn't feel the need to see a computed p-value -- it
would be sufficient to know that the "conjunction" contrasts were
truly orthogonal and know the level that each one was
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