Dear SPM-users,
I have performed an event-related fMRI study in 9 subjects with 3 different
conditions (c1, c2 and c3). I have specified a model including the three
conditions and temporal derivatives. I have 2 questions about the results of
the data analysis:
1. The F-contrast (effects of interest) shows only few small significant
regions at p<0.05 (uncorrected). However, if I look at the contrast c1-c2
(i.e. 1 0 -1 0 0 0), I get highly significant effects in those areas I
expected to see. How is it possible that I don't find these regions in the
F-map? (I think it is important to add that the contrast 0 0 -1 0 0 0 did
not show a significant effect either).
2. If I want to plot the adjusted data of the areas showing significant
c1-c2 difference, it appears that this is not possible. I get the message
"no raw data has been saved at this location". I assume that this has to do
with the fact that there is no significant F-contrast at the same location,
and therefore no raw data has been saved there. Is there a way to plot these
data?
Thank you,
Serge Rombouts.
SARB Rombouts, PhD
Dept. KFI
University Hospital "Vrije Universiteit"
De Boelelaan 1117
P.O. Box 7057, 1007 MB Amsterdam
The Netherlands
Tel: +31 (0)20 4440316
Fax: +31 (0)20 4444147
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