Hi Xuelin,
> I have a question on spatial map in MELODIC. My spatial map seems a
> bit discrete for those orange and blue dots. I wonder how can I
> make the spatial maps seem more blurred. ig. Maybe I can apply some
> mask to post process those spatial maps. Is there such a method in
> MELODIC?
I think it would be unusual to smooth the ICs as a post-processing
step. Instead, it would be more typical to smooth the input data as
the final pre-processing step, much like with the usual GLM approach.
(Smoothing would be pre-stats, but post- other pre-processing, such as
motion correction, realignment, normalisation, etc.)
> Also, there are 2 options in the 2nd tab in MELODIC GUI, and they
> are Spatial smoothing FWHM and Temporal filtering respectively.
> What can they do in MELODIC?
These options are passed to the "ip" program, which Melodic calls to
perform spatial smoothing (Gaussian blurring) and low-pass filtering
of its input data.
> Is it gonna blur the spatial map if I modify any of these 2 parameters?
By increasing the FWHM for the spatial smoothing, the input data will
be smoother, and this will probably make the resulting ICs smoother as
well. You should probably choose the FWHM to approximately match the
smallest scale of the activations/effects that you are looking for,
but a bit of experimentation might be needed.
HTH,
Ged
P.S. I hope that saves CB a reply, but I'm sure he'll correct me if
I'm wrong...
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