Dear SPMers,
I have some questions about how I can set up the First Level Analysis
(seed-based connectivity analysis) for resting state FMRI data using the
GUI. As I see it, this is how I need to go about it:
1. Preprocess the data (slice timing correction, realignment,
coregistration, normalisation, smoothing)
2. Extract time series from a given seed
3. Use that as a regressor in the GLM
My questions are as follows:
1. How should I extract the time series from a given seed mask? I have
used fslmeants in FSL for this before, but I wanted to know what SPM
script I need to use to get this.
2. In my GLM, what should I input as the conditions? Can this be left
blank? Or should it be Onset:0 and Duration:till the end of the scan
3. How does SPM differentiate between regressors of interest and nuisance
variables? For example, where do I need to specify the time series of my
seed, and where should I specify movement parameters and maybe White
Matter and CSF-associated timeseries as confounding variables?
4. How should I define the contrasts taking these regressors into account?
Looking forward to your inputs on these!
Thanks very much!
Best,
Rashmi
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