I am a SPM beginner user and appreciate if you can give me some advise on doing conjunction analysis since I found it a bit confusing.

I have two brain areas X and Y which are neighbours and show selective activation  in two different conditions. I want to claim that these two brain areas do not overlap functionally and anatomically although the two conditions are pretty much similar. Absence of overlap is clear after group analysis but one may argue that this can still exist at the level of single subjects.  I was recommended to generate an overlap map of the different individuals for the two functionally defined areas as was suggested by Heler and colleagues. Heller, Ruth, et al. "Conjunction group analysis: An alternative to mixed/random effect analysis." Neuroimage 37.4 (2007): 1178-1185. This allows the assessment of how many subjects showed selective activations in each voxel and therefore shows the extent of overlap within and across subjects. 

My question is whether this approach is the same conjunction analysis offered by SPM. If so, what would be the reasonable p-value to choose while performing this analysis in SPM for each individual subjects. And, after having it done for each individual subject how I can do statistics on conjunction results obtained from each individual subjects since the SPM shows the results only on the glass brain.

Thank you very much in advance.

Best regards, Hamid