Dear Dough,
>
> In SPM ;In ImcCalc I would like to simply calculate and display the mean
> percent change across pre-post scans across subjects as an image.
>
> Thus 10 people scan1 scan2 so Subject scan1 scan2 Subject2 scan1
> scan2....
>
> =mean( (i1-i2)/i1)+(i3-i4)/i3+....)
>
> when I try versions of this in ImCalc I get weird scaling etc
>
> Any help appreciated
>
Try: ( (i1-i2)./i1) + (i3-i4)./i3 + ... ) / 10
I think the "mean" function won't work unless you're using spm_imcalc as a
matlab function. So in your case, you have to explicitly divide by the
number of subjects.
All the best,
Kalina
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Kalina Christoff Email: [log in to unmask]
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