I have just ran mri-glmfit on cortical thickness data and corrected for multiple comparisons using Monte Carlo Simulation. I have significant clusters (cwp < .05), however, when I analyse the average thickness measures from the xxx.y.ocn.dat file in SPSS, there are no significant differences between my groups. I'm not sure if I am using the correct approach to extract thickness values for the significant clusters. 

Thank you for your help,

Sinead 
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