First time FIR user here,
We used the FIR approach and constructed a model consisting of separate
regressors for each of our trials (trial 1, trial 2, trial 3...trial 5).
[Each trial X was presented 30 times in the design.] After estimation, we
popped open the contrast manager to start performing contrasts and, well,
we are confused and need some help. :(
We see beta images have been created for Trial 1....to Trial 5. Perfect.
And then we also see listings for (something like) Trial 1 x Trial 1,
Trial 1 x Trial 2.....which continues and ends with Trial 5 x Trial 5.
Rather than flying blind, we thought it best to see if some kind soul
would help us unwashed by providing us some insight into what each listing
reflects. We also need gudiance on how in the contrast manager we might go
about finding activation correclated with each of our trial types (1, 2,
3, 4, 5)---assuming one can; in the past, we've simply used the HRF and
HRF plus derivatives, defined the contrastt and then carried things to the
second level without a problem. But here, with FIR, it seems we must
follow a different approach.
Much thanks for any help
Mike
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