Hi, this highpass may be unnecessarily long - for such multi-condition
designs I would recommend using the contrast estimability function in
the FEAT GUI to check the effect of reducing the highpass cutoff.
Cheers
------------------------------------------------------------------------
Stephen M. Smith, Professor of Biomedical Engineering
Associate Director, Oxford University FMRIB Centre
FMRIB, JR 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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On 23 Jun 2008, at 20:36, Betina Ip <[log in to unmask]> wrote:
> Hi Steve,
>
> My activation vs rest paradigm is for each epoch consists of 6
> conditions: 4 active conditions,
> and 2 rest conditions (which are treated as one). Each conditions is
> randomized within the
> epoch, and counterbalanced across the scan. One epoch contains 2
> blocks (16 s each) of each
> condition. I model the active conditions and leave out the 2 rest:
>
> A>B 1 -1 0 0
> B>A -1 1 0 0
> A>rest 1 0 0 0
> B>rest 0 1 0 0
> C>D 0 0 1 -1
> D>C 0 0 -1 1
> C>rest 0 0 1 0
> D>rest 0 0 0 1
>
> The highpass filter is set to 144s (6*16*1.5)
>
> Many thanks for your response!
>
> Betina
>
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