Hi Donald,
Thanks so much for the quick reply! I'll definitely shift over to the gPPI toolbox
- but I am a bit confused by the response:
In the SPM12 manual, the PPI example has 3 conditions ("Stationary, No-attention, Attention") in the GLM SPM.mat, and but uses only the two conditions (Attention>No-attention) for the PPI analysis.
This is what motivated my thinking that I could carry this approach forward (to be concrete, what I'm actually trying to do is remembered_repetition1>forgotten_repetition1 PPI, while the GLM model also includes remembered_repetition2 and forgotten_repetition2 regressors that model events later in the session)
Is the manual's example approach simply suboptimal for this 3 condition scenario (looking through the gPPI tutorial I am thinking this is the argument)? Or have I misunderstood the relationship between the example and what I hope to do?
Again, thanks for the guidance!
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