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The contrast for high temperature alone is: ones(1,N)/N CE --> ones(1,14)/14 1 0where N is the number of subjects and CE is the condition effect (e.g. 1 0 or 0 1, for high temp and low temp respectively). 2009/6/4 Ming-Tsung Tseng <[log in to unmask]> > Hi SPMers, > > (Here I paste my question again for more clear description) > > In my experiment, 14 subjects received 2 fMRI scannings (low-temperature > vs. > high-temperature stimuli), and I want to investigate the difference in > brain > activations for the 2 stimulus temperatures. > > The contrast “(high temperature) minus (low temperature)” means that which > brain regions show significantly higher responses for the high-temperature > stimulus than those for the low-temperature stimulus. > > I used paired t-test in SPM5 to perform this analysis. The procedures are > as > follows: > > (1).14 pairs of con*.img files (low temperature vs. high temperature) for > each > subject were established > (2).The JPEG of the design matrix is attached > (3).The contrast was 0 0 0 0 0 0 0 0 0 0 0 0 0 0 -1 1. > (4).Then I got the activation map > > However, I want to get another map..... > > The contrast “(high temperature) minus (low temperature), with the (high > temperature) as the inclusive mask” means that which high temperature- > activated brain regions show significantly higher responses for the high- > temperature stimulus than those for the low-temperature stimulus > (Is my understanding correct?). > > Again, I used paired t-test in SPM5 to perform this analysis. However, how > can I “mask” the “(high temperature)”? Because it seems not allowed to > establish the contrast “0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1”. > > Can I inclusively mask “(high temperature) minus (low temperature)” > with “(high temperature)” in the paired t-test analysis in SPM5 2nd-level > analysis? > > I'd appreciate for any help. > > Thanks > > Dr. Tseng > > > -- Best Regards, Donald McLaren ===================== D.G. McLaren University of Wisconsin - Madison Neuroscience Training Program Office: (608) 265-9672 Lab: (608) 256-1901 ext 12914 ===================== 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 (608) 265-9672 or email.