Hi Laura, Usually you just average within your ROI in lieu of smoothing Cheers Bruce

On Apr 13, 2011, at 5:33 PM, "pikase@tin.it" pikase@tin.it wrote:

Dear FS experts,

I'm quite sure this is a very trivial question since apparently it hasn't been posed previously.

I'm performing a CT analysis with the aim to compare two groups of subjects, which are different regarding the degree of expertise in a given area (experts vs non experts) and using as covariates age and gender. The total number of subjects is 21 for the expert group and 20 for the naive subjects.

At first I performed a whole brain analysis both via qdec and command-based, wich reveal substantially no differences between the two groups.

Now, I also have some a-priori ROIs I would like to test. I went several times through the steps suggested in the tutorial, but still something is not clear to me. Do I need to apply a smoothing on the ROI I want to draw? I would assume so. How can I do that? Is it possible to extract ROIS from previously smoothed data? (All my datas have been passed through -qcache).

Thanks so much for your time and help!

Best regards,

Laura

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