I'm also talking about where in the code each step is handled in SPM.
> On Wed, 16 Jan 2008 12:31:57 -0800, Linda Seltzer
> <[log in to unmask]>
> wrote:
>
> >Does anyone written a paper or tutorial applying the well-known concepts
>
> of
> >sampling, aliasing, Nyquist theorem, etc. to data analysis in SPM?
> >Specifically, TR and sampling rate; spectrum of voxel data vs time, the
> >same with noise; how the concept of jitter relates to this; upsampling
> to
> >convolve the delta fns with hemodynamic response (for the regressors)
> and
> >then downsampling the signal back, when each step is done. I would like
>
> to
> >see a description from a signal processing engineering viewpoint of how
> all
> >of the sampling rates and bandwidths are handled. If there is nothing
> >formal, but someone has made some notes deriving all of this, I would
> like
> >to read them and learn more. I would like to have an overview of all of
> >the sampling rates and spectrums involved.
> >Linda Seltzer
> >[log in to unmask]
> >[log in to unmask]
> >=========================================================================
>
> IMHO a useful way to look at this is to not restrict consideration to SPM,
>
> but think about fMRI analysis in general (restricted to the case of
> univariate statistics, as opposed to multivariate methods). Then look for
>
> articles in the published literature via Google or PubMed. There's quite
>
> a bit out there.
>
> Just to take an interesting an relevant example, the problems of aliased
> noise from cardiac and respiratory cycles is discussed quite frequently.
>
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