If you have two tasks, i.e. "task" and "control" then yes you put them
as two EVs, and contrast them with (e.g.) [1 -1].
If you have just one task, and want to compare that to baseline, then
you have one EV, and contrast the task with baseline using [1]
Steve.
On 22 Jan 2009, at 22:02, Lin Nga wrote:
> Hi everyone,
>
> Sorry if I'm treading old grounds here but it isn't exactly clear to
> me how
> FSL compares the EVs to fixation condition if it isn't explicitly
> set as an
> EV. For example if there are two EV's, task and control, I know that
> if I
> wanted to contrast task to fixation I would use [1 0]. Wouldn't task
> be
> contrasted to both control and fixation in this case, since control
> is set to 0?
>
> Thanks again,
> Lin
>
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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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