HI - have you tried using the model Wizard, as suggested in the
manual? This will do the basic setup for you.
Steve.
On 5 Jun 2009, at 19:03, Nicole Pelot wrote:
> Hi,
>
> I have read the FEAT Perfusion documentation quite a few times now,
> but I
> still cannot figure out how to properly set up my EVs. I have a
> block design
> task: 56s/block, 7 blocks, alternating between rest and active
> (start &
> finish with rest).
>
> My main issue is with EV1. It clearly states that we should be
> modeling
> *rest* times, but that leads me to think of a block design with 0's
> for
> active and 1's for rest. However, the sample design seems to show
> all 1's
> for EV1. Also, what convolution should be applied? None?
>
> I've structured EV2 as I always do to correspond to my block design.
> (On:
> 56s; Off: 56s; Convolution: Double gamma).
>
> EV3, I chose "Interaction", and I made the mean of EV1 zero (but the
> min of
> EV2).
>
> Thank you,
>
> Nicole
>
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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
+44 (0) 1865 222726 (fax 222717)
[log in to unmask] http://www.fmrib.ox.ac.uk/~steve
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