Dear Thomas,
> I have a question regarding the SPM{Z} projections obtained by the
> Results function in SPM:
>
> When I display the results of an fMRI analysis by entering
>
> height threshold 0.001
> use corrected extent threshold: yes
> corrected p value: 0.05
>
> I get a larger number of activated regions than when I use
>
> height threshold 0.01
> use corrected extent threshold: yes
> corrected p value: 0.05
>
> I would think that I have to see a larger number of voxels
> activated when I use a height threshold of 0.01 than with 0.001 ?
Yes you do. You should get a larger number of voxels 'per cluster'
activated when you use a low height threshold. However the number of
clusters will be smaller. In other words the size threshold increases
as the height threshold decreases.
I hope this helps - Karl
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