Dear Vincent,
> Of course you cannot get additional information by interpolating the
> data, but I thought it was a good way to avoid the loss of spatial
> resolution which occurs when smoothing with a kernel of width 2-3 times
> the acquisition voxel size. With interpolated data it would be possible
> to reach the criterion "voxel size < FWHM", i.e. a sufficient
> smoothness for the lattice assumption to hold, with very little
> smoothing, i.e. nearly no loss in spatial resolution.
>
> Could you or anyone else comment this ?
I think this exactly right. Subsampling and convolution with the
original PSF ensures a 'better' lattice approximation with minimal loss
of spatial resolution. However, it should be noted that smoothing
generally increases sensitivity to evoked responses (whose spatial
scale may be larger than the voxel size e.g. hemodynamic responses) at
the expense of resolution. This is particularly pertinent for
multi-subject designs.
With best wishes - Karl
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