Dear FSLers
I am trying to analyze a fMRI dataset collected using the following sequence diagram,
1, 'stim1' ( on for 8 seconds)
2, collect 4 scans (S11, S12, S13, S14) with 'stim1' off but 'stim2' on (TR=2s)
3, rest for 8 seconds
4, 'stim3' ( on for 8 seconds)
5, collect 4 scans (S21, S22, S23, S24) with 'stim3' off but 'stim2' on (TR=2s)
6, rest for 8 seconds
7, 'stim1' ( on for 8 seconds)
8, collect 4 scans (S31, S32, S33, S34) with 'stim1' off but 'stim2'on (TR=2s)
9, rest for 8 seconds
10, 'stim3' ( on for 8 seconds)
11, collect 4 scans (S41, S42, S43, S44) with 'stim3' off but 'stim2'on (TR=2s)
12, rest for 8 seconds
.......................
It is essentially an modified event-related experimental design.
'stim2' ( actually 'the gradient noise') is always on in data collection
steps only (step 2 , 5, 8, 11 ..... in above). And I want to apply
paired-t test on this data to get the contrast between 'stim1' and
'stim3', namely, compare the pairs of (S11,S21) (S12, S22) (S13, S23)
(S14, S24) (S31, S41) (S32, S42) (S33, S43) (S34, S44)..........
I am not sure whether FEAT is capable to do this kind of analysis. If
positive, how?
Thanks
Chen
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