Hello !

I recently realised that what we see in Surf Ice is the intersection between the brain mesh and the 3D file that we display on it, which implies that if a signal is really close to the surface, it won't appear on the smoothest brain meshs. Is there a way to increase the depth of that intersection, so that it would appear anyway (but just less intense, as it would be a mean with voxels containing no signal) ?

Thank you in advance !

It is ideal to use Surfice for statistical overlays that are calculated based on mesh vertices rather than voxel intensities. For voxels, you need to project the voxel location onto the mesh, and this will not be accurate, in particular for dilated meshes. Since the voxel to mesh projection is only for illustrative purposes, the implementation is pretty crude. It will either be based on the voxel nearest the vertex (nearest neighbor), or it will compute the average (trilinear interpolation) of the eight voxels nearest the vertex. The choice between these is controlled by "Smooth voxel-based images" in the preferences window. The code is open source, so you can always implement more sophisticated methods. Alternatively, you could convert the voxels to mesh vertices using another tool that saves data in a fomrat Surfice supports, like GIFTI.