Hi,
You can just use Featquery to get the % signal change as it will take
care of all of these issues for you.
Cheers.
On 5 Dec 2007, at 17:47, Paymon Hosseini wrote:
> Hello,
>
> I have an event related study that has 6 experimental conditions a
> lot of control conditions. For analyzing it, i just modeled the 6
> experimental conditions and the rest period (i.e fixation) and
> ignored the control conditions (for now).
>
> My question is about calculating %signal change for the 6
> experimental copes (each cope is one experimental condition minus
> fixation). Specifically, i am wondering how i should calculate the
> baseline to get the %signal change relative to fixation. I suspect
> that I cannot use filtered_func_data as baseline, because it
> includes all the control conditions that i have not modeled. A
> possible solution may be to concatenate all the fixation periods of
> a subject into one volume, and then divide the copes by this new
> volume and then multiply by 100 to get the %signal change. Is this
> correct?
>
> thank you very much for any help,
> paymon
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Stephen M. Smith, Professor of Biomedical Engineering
Associate Director, Oxford University FMRIB Centre
FMRIB, JR Hospital, Headington, Oxford OX3 9DU, UK
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