On Mi, 1.04.2009, 11:46, Torben Ellegaard Lund wrote:
dear alexander:
you could as well use a brain mask for your
second level analyses and the 'eye activations' will be masked
out from the group results;
you could use the one provided in the apriori subdirectory of spm
(brainmask.nii)
hth, claus
> Dear Alexander
>
> If the eye-artefact is only there in some of the con images it will
> not make it through the threshold in the final second level analysis.
> This could have been the case in a fixed effects analysis but not in a
> random effects analysis. If you want to avoid those artefacts you
> could include a time-series from an eye-voxel in your design matrix.
> This would most likely remove the eye-artefact, but you risk removing
> some of the activity as well.
>
> Best
> Torben
>
>
>
> Den 31/03/2009 kl. 16.56 skrev Alexander Lebedev:
>
>> Dear SPM experts
>>
>> I decided to check my old results, and found one problem. When I
>> have opened con*-files in xjview tbx, strange thing appears... There
>> are activations of eye movements (notwithstanding of Normalization)
>> in some con*-files. May I include such results in group study? Could
>> you advice me any solutions to prevent this trouble?
>>
>> Thank you beforehand
>>
>> Best Regards
>> --
>> Alexander Lebedev.
>
>
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