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Dear SPM experts, I have 3 within subject conditions: positive, neutral, and negative. My goal is to determine the common brain region that is activated by ALL three conditions by using a 2nd level conjunction analysis. I have two questions: 1) since my 3 conditions are not orthogonal (all three are different levels of the same dimension), is conjunction analysis even a valid option? 2) what p value shall I choose to view my conjunction results? That is, if my intended p values is 0.001, shall I put 0.001 or .1 (.001^1/3), as some previous posts seem to suggest? To do this conjunction analysis using SPM8, I choose all three conditions, then conjunction null (not Global). Many thanks! Jingwen