As a newcomer both to the list and to neuroimaging, I hope this is an
appropriate question!
I am primarily interested in fMRI studies comparing psychiatric and control
groups in both younger and older adult populations. Because of a general
physiological slowing or differences in global CBF (due to age or
psychiatric status), it is conceivable that I will have group differences
in the speed of hemodynamic responses, but not necessarily their intensity
or location. (e.g., the shape of a hemodynamic response curve to a
stimulus would be the same in both groups in a given voxel, but the peak of
that curve would be slightly delayed in one group vs. another.) How would
that difference be reflected in FSL/FEAT results, if at all? If I wanted to
control for that difference, what would be the best way to go about it
(e.g., entering a behavioral reaction time score as a covariate?)
Thanks for your help and advice,
--Moria Smoski
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