Hi - I'm not sure about the other software options, but Optseq does afaik
allow multiple event types - see http://surfer.nmr.mgh.harvard.edu/optseq/
Any thoughts on this Doug?
Cheers, Steve.
On Wed, 22 Sep 2004, X Liu wrote:
> I am about to design an ER-fMRI experiment with multi-event trials. I am
> aware of a few optimization programs for single-event trials (e.g., Doug's
> optseq, AFNI's RSFgen/waver/3dDeconvolve, UCSD's m-sequence, and Wager's
> genetic algorithm). But none of them can be readily applied to design with
> multi-event trials.
> Say I have a trial with four events -- "cue" (5 levels), "response" (2
> levels), "feedback" (2 levels), and "blank". I would like to estimate the
> brain activation of each level (except for "cue", just overall effect) of
> each event (except "blank") within a trial independently, but don't want to
> resort to long resting period after each trial. Does any one have
> experience on this type of design and optimization?
> I am thinking about optimizing just the "feedback" event since "response"
> event is subject specific and "cue" event partially depends on the
> previous "response" event. Also, maybe after every 6 trials (pseudo-block),
> add a resting period of about 16 seconds, instead of long resting period
> after each trial.
> A related issue is that the two levels of the "feedback" event do not
> necessarily have equal probability. Does this affect the optimization in
> terms of looking at the contrast of these two levels?
> Thanks very much for any suggestion.
>
Stephen M. Smith DPhil
Associate Director, FMRIB and Analysis Research Coordinator
Oxford University Centre for Functional MRI of the Brain
John Radcliffe Hospital, Headington, Oxford OX3 9DU, UK
+44 (0) 1865 222726 (fax 222717)
[log in to unmask] http://www.fmrib.ox.ac.uk/~steve
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