Dear SPMers
This interesting concept is still rather obscure to me in the way it can be
compute.
The way I figure it is that practically the temporal evolution (fMRI) of a
highly significant voxel (or any voxel) is used as covariate of interest.
Is this true ?
If true :
1- What is the easiest way to get this vector using SPM99b ?
2- Is this vector supposed to be corrected (whipping out the part of
covariate of no interest) => how to do it (without programming a new matlab
function :)) ?
3- Wouldn't it be more interesting to use a cluster ? (may be a good
smoothing can do the same)
4- One can suspect a functional connectivity to be displayed within a task,
but not with an other. Let say you which to see the effect of one factor on
a fMRI acquisition with 3 conditions : Rest, Active1, Active2. How will you
put your vector in ?
5- The way I figure it could only be name functional connectivity, not
effective, since no model is imposed. True ? Thus to do effective connec
tivity, one should plot the intensity of one voxel against the one of
another that have to be specified (another activated regions for example).
Many thanks for any comments or advises on that point
Best regards
Jack
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