Dear afni experts:
I am involved in analyzing the data for an experiment with a very unusual
design. Since the design is so different, any advice you might have on how to
analyze the data would be much appreciated. The design is as follows:
Two groups (patients and nonpatients) completed 4 tasks: 6 minutes
baseline(continuous), 24 minutes state induction (continuous), and 6 minutes of a
control task (continuous). One minute of "fixation" followed each of these tasks.
State induction and the control task were counterbalanced in both patients and
controls.
Given this design, we have a few questions:
1) Except for fixation, there was only one on period for each task. Given that,
can we use a 3dANOVA3 -type 5 to analyze the data or must we use a 3dANOVA2
-type 1?
2) Given that state induction is so long, is it possible for baseline to be
longer or shorter than the other time periods in the deconvolve?
3) We are also interested in comparing the early and late time points of state
induction. To do that, is it more appropriate to censor out the middle time
points in state induction or to divide them up into smaller "chunks" even
though they are not independent tasks?
Any insight or advice would be much appreciated. Thanks again!
-Mariko
