Dear Christian and Patrick,
Concerning the second point, a more principled approach would be
preferable but you could have a look at spm_mesh_to_grid.m, this is what
we use for statistical inference from M/EEG source reconstructions.
On 08/01/2019 09:14, Christian Gaser wrote:
> Dear Patrick,
> On Mon, 7 Jan 2019 16:43:29 +0000, Patrick <[log in to unmask]> wrote:
>> Dear Dr. Gaser/CAT Users,
>> Greetings for the new year!
>> I have two questions:
>> 1. Once the surface pipeline is run during the segmentation stage, is there a way to export the subject level regions from the surface atlases? I am interested in using the surface segmentation for functional connectivity analysis. Is such a thing possible?
> No, this is not possible because of the missing inverse surface deformation (from template to native space). However, you can use the atlas definitions in normalized space, which might be a good alternative in that case:
>> 2. Are there in-built utility in CAT to export surface files to volume file? From a brief survey, it seems that the reverse is possible (i.e. a volume file can be projected as a surface file). I am wondering if the reverse is also possible?
>> For both the above, I understand that moving between surface and volume can be inaccurate and problematic. From literature review, it seems that various groups have used freesurfer parcellation for graph theory analysis. I would like to know if I could do the same using CAT surface analysis.
> While the mapping from volume to surface is relatively straightforward, the opposite way is not possible. There is no point-to-point mapping possible and the values in the volume that are not crossing the surface should be interpolated.
>> Many thanks for your time and help
>> Best Regards
Guillaume Flandin, PhD
Wellcome Centre for Human Neuroimaging
UCL Queen Square Institute of Neurology
London WC1N 3BG