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Dear SPMers, Do you know if there are any DMN masks available. I am interested in exploring group differences within the DMN for my healthy elderly and Mild Cognitive Impairment groups. In my experiment, I have a group factor and a repeated measures factor: working memory load over 3 levels. As an alternative to a DMN mask, could I use a mask based on task-negative activity averaged across load, i.e. all activity below implicit baseline (-1 -1 -1)? When I have done this the task-negative regions show a striking resemblance to the regions of the DMN. Would it be appropriate to perform a global null conjunction for both groups for this negative effect t-contrast, save this as a mask and then test for group differences or group x load interactions in this ROI? Nicky Kochan PhD student, School of Psychiatry, University of New South Wales