second level statistics

[Michael Wibral]

Dear Fieldtrippers,

I have computed sourcestatistics (task vs. baseline) at the single subject level for two separate conditions (Cond 1 and Cond2)
I then use these t-values source images to comapre the activations between the two conditions at the multi-subject level. Works fine.

My question is whether there is any straightforward way in fieldtrip to recycle these results (sourcespace t-value images) for a multisubject analysis for task versus baseline for condition separately. What appeals to me is that these data (t-values) are 'normalized' in a meaningful way across subjects already. Would it be statistically valid to create a virtual "baseline-against-baseline" dataset (with all t-values equal to zero, of course) and test against this?

 Or would it be better to do sourceanalysis once more to get task and baseline source power for each subject and condition and then do the regular source statistics task-vs-basline for each condition?

Any suggestions welcom,
Michael Wibral

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