Hi.
When you discard the first 3 images, then the 4th scan will be your
first scan.
( You should be aware that the first scan in your design matrix is time
= 0 or scan = 0 )
Best.
Walter
Michelle Umali schrieb:
> hello all,
> i usually use Analyze files but am now using nifti format. When I do
> pre-processing I ignore the first 3 volumes (6 seconds for a TR of 2)
> and select from volume 4 onward from the virtually split nifti image.
> I simply discarded them when using Analyze files, but I am unsure how
> this works in nifti and virtually split files.
>
> How does one account for this when defining condition onsets?:
>
> If a condition started at the 4th scan collected, is the onset defined
> at the 4th scan even if the first 3 volumes were discarded?
>
> Or is the 4th scan now the 1st scan because I ignored the first 3
> volumes ?
>
> Thanks!
>
> Michelle
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