Dear Yael,
You should not model the rest/baseline/fixation condition in FEAT.
Whatever you did to set up the model with it included should not
have worked (it should have complained about it being rank deficient)
so it probably just wasn't set up correctly (with the right durations
or timings).
As for image format, the *preferred* format for FSL is NIfTI which
has an extension nii (or nii.gz if it is compressed). This is what
we say that people should use on our documentation and webpages.
Why did you think you needed a hdr file? This is the old Analyze
format which we now discourage people from using. If you have
found a place where it says you should use this then please let us
know so that we can update it.
All the best,
Mark
Yael Shani wrote:
> Dear fsl-ers
>
> I have two separate questions regarding FEAT analysis for an event
> related design:
> 1. As far as I understand from the tutorial guide of FEAT, for an
> event related design I do not need to define the rest (the Fixation
> display) as an event. Am I right?
>
> I tried to play with the data and just for the curiosity I did define
> the rest as an event. I ran two contrasts: one examine the impact of
> the stimuli (1 0) and the other is the difference between the stimuli
> to the rest condition (1 -1).
> I received different results in the FEAT display for both conditions.
> Why is that?
>
> 2. The second question deals with registration. I transformed the data
> (including the anatomical data) from DICOM to AFNI and recieved the
> files with nii ending and not hdr.
> Can I use the nii file? If not, how can I transform the nii file to an
> hdr file?
>
> Many thanks
>
> Yael
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