Hi! I am trying to come up with the best way to compare the fit of the canonical response used by FSL in analysis and the actual blood flow response to six different conditions (averaging across participants). I would like to show that any sig. differences between conditions are not being biased by differing model fit.
In my eyes plotting the blood flow response to each stimulus type in each condition and comparing this to the canonical blood flow response would be one way to do this. I'm considering the following –
1. for each session for each participant, taking the data from ps_tsplot_zstatX_ev#.txt
2. from this file, averaging the full model fit results for each given ev, to get an average blood flow response to each condition type
3. plotting the result for each condition against the canonical response
Three questions
A. does this sound reasonable?
B. wrt the organization of data in the txt file, I am correct when I consider averaging the data for the full model fit column (column 3) for each event, correct?
C. if i used gamma modelling in my analysis, it's valid to just convolve a single impulse at time 0 with a gamma waveform in matlab to plot this response, right?
With thanks!
Christopher
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