This topic has been discussed recently, and I was told to look into a
Friston, 1997 technical note (Human Brain Mapping 5:133-136) for
determining significance of apriori locations of interest. My question was
'can I use uncorrected p-values for voxels in an apiriori region of
interest?' It appears that this article is geared specifically for
determining the significance of apriori regions based on the spatial extent
of significant regions nearby, when that apriori region does not appear on
the output to be significant. However, my apriori area of interest is broad
(dorsomedial prefrontal cortex) and indeed, I do find significant voxels
(uncorrected) in that region that upon correction, do not remain
significant. Therefore, I don't need to worry about spatial extent of sig.
voxels nearby since I do have sign. voxels (uncorrected) in my region
already. I hope that was clear- anyway, the article does not answer my
question- which remains, can I use uncorrected p-values for voxels in the
dorsomedial pfc?
Thanks for your input.
Karen
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Karen Bell
PET Facility
B-938 PUH
200 Lothrop St.
Pittsburgh, PA 15213
(412) 647-9721 (wk)
(412) 647-0700 (fax)
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