Hi Mike,
May I ask what does "to use a mask (your ROI(s)) on your results and then specify a corrected voxelwise threshold" mean? Do you mean I use the ROI as an explicit mask in my 2nd level model, i.e., before model estimation? However, this approach seems not the exact svc.
But please someone could confirm that steps 1-4 below are correct for a svc procedure. My question is for (1), can I use a lenient initial threshold?
(1). an intial uncorrected threshold, e.g. 0.001
(2). select "small volume" in SPM8
(3). define the small volume, either a sphere centered at predefined coordinates (e.g. from previous literature) or a mask (e.g. from an anatomical mask in an atlas)
(4). check the peak-level threshold. If a voxel survives FWE 0.05, it is regard as significant.
Mike
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