The color wheel in tksurfer is not well supported. It's pretty old code, and it is surprisingly not very useful. It is not really appropriate for retinotopy, despite all the pubs that use it! It is good for applications where there is a spatial discontinuity in phase.

doug

Andreas Schindler wrote:

Dear all

I realised that freesurfer can handle overlays of complex numbers (e.g. as given by a fourier analyis) when they are split up in two separate volumes: one containing the real and the other containing the imaginary part of each voxel ("complex numbers" flag in the overlay configuration menu). It seems that freesurfer is able to read out the phase angle for each voxel and to depict different phases as different colours. However, unfortunately, when using the colour wheel, I haven't managed to figure out yet what colour corresponds to what phase (I assume the angles range from pi to -pi).

Does anyone know how to interpret the colour wheel in that context?

Many thanks, anyway

best wishes

Andreas _______________________________________________ Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer