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Hi - it runs a multiple regression - I suggest having a look at the into to GLM and contrasts at the end of the FEAT manual.
Cheers.


On 14 Apr 2011, at 18:18, Sang Lee wrote:

Hello FSL list,

When FSL analyzes paradigm file for a given fMRI run, how does it analyze it?

For example, if I have five different EVs (A - E):

TRs A B C D E
0 0 0 0 0 0
1 0 0 0 0 0
2 1 0 0 0 0
3 1 0 0 0 0
4 0 0 0 0 0
5 0 0 0 0 0
6 0 1 0 0 0
7 0 1 0 0 0
8 0 0 0 0 0
9 0 0 0 0 0
10 0 0 1 0 0
11 0 0 1 0 0
12 0 0 0 0 0
13 0 0 0 0 0
14 0 0 0 1 0
15 0 0 0 1 0
16 0 0 0 0 0
17 0 0 0 0 0
18 0 0 0 0 1
19 0 0 0 0 1

and I want to only look at condition A: I would set the contrast to 

Contrast EV(A) EV(B) EV(C) EV(D) EV(E)
      A    1    0    0    0    0

1) Now, does FSL looks at condition A and compare it with the average of all other conditions (B-E)? 

OR

2) does FSL looks at condition A and compare it only to those TRs that have zeros (e.g. baseline) across all five EVs? That is, it is modeled only against our baseline condition, and not against blocks of other conditions.

Thank you for your help.




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