 |
 |
A couple of comments: (1) This is not a ROI analysis. An ROI analysis is where you extract the ROI values and do statistics on them. You are doing an analysis with a mask. (2) It is best to do the masking at the second-level and after model estimation. The reason being it that you can always look at a particular brain region using a mask, but you can never go from an explicit mask to another brain region. You'd have to change all of your first- and second- level models. Best Regards, Donald McLaren ================= D.G. McLaren, Ph.D. Postdoctoral Research Fellow, GRECC, Bedford VA Research Fellow, Department of Neurology, Massachusetts General Hospital and Harvard Medical School Office: (773) 406-2464 ===================== This e-mail contains CONFIDENTIAL INFORMATION which may contain PROTECTED HEALTHCARE INFORMATION and may also be LEGALLY PRIVILEGED and which is intended only for the use of the individual or entity named above. If the reader of the e-mail is not the intended recipient or the employee or agent responsible for delivering it to the intended recipient, you are hereby notified that you are in possession of confidential and privileged information. Any unauthorized use, disclosure, copying or the taking of any action in reliance on the contents of this information is strictly prohibited and may be unlawful. If you have received this e-mail unintentionally, please immediately notify the sender via telephone at (773) 406-2464 or email. On Tue, Mar 8, 2011 at 12:56 AM, Yuko <[log in to unmask]> wrote: > Dear SPMers > > I have one question about ROI analysis. > When I do ROI analysis, should I use explicit mask (anatomical mask created > by WFU pick-atlas) in 1st level, then create con image (condition A - > condition B), and bring these con images to 2nd-level? > Or should I create con image of each condition (condition A and B) without > explicit mask, and bring these con images to 2nd-level and set contrast > (condition A- condition B), then use WFU pick-atlas to do ROI analysis? > > I wonder which way is the correct one to do ROI analysis. > > I read answer of mailing list, but I couldn't find the mail which answered > my question. > > Any answer is kindly appreciated. > > Yuko >