Dear SPM Experts,
I still have some basic questions about the Contrasts ins SPM99. I'm
looking at a quite simple paradigm with the conditions [A B R] and would
like to test for Voxels where the activation for A is significantly
higher than for B.
If I look at the results for the Contras 1 -1 and plot the
event/epoch-related response for these voxels, all plots show me
activation for A and deactivation (negative response function) for B. I
just wonder what happened to the voxels where there is activation for
both contrasts but more for A....
Is this a problem with my data or do I understand something wrong about
SPM?
Is there any other Contrast that would test for A>B? For Example would
something like [+2 +1] make any sense at all?
What would be the apropriate Contrast for three conditions A B C that
tests for A > B & C ?
Finally I've got a completely different problem with the SPM
Slice-Timing.
Using the following parameters the routine constantly crashes before
doing anything:
1 Session, 300 Images, Ascending ,TR=3.2, TA=2.4, Ref.Slice=21 (Top)
The Error Message is:
??? In an assignment A(matrix,matrix) = B, the number of rows in B
and the number of elements in the A row index matrix must be the same.
Error in ==> /usr/local/spm99/spm_slice_timing.m
On line 255 ==> stack(nimgo+1:end,g) =
linspace(stack(nimgo,g),stack(1,g),nimg-nimgo)';
??? Error while evaluating uicontrol Callback.
Could anybody give me a clue about what's going wrong here?
Thanks a lot in advance!
Wolfgang Weber - Fahr
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Wolfgang Weber - Fahr
NMR-Research, zi-Mannheim, Germany
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