Hello, I generated a 3D mesh mode of the marmoset cortex from nissl stained slices, and I am looking for ways to flatten it. I managed to save my mesh to the FreeSurfer format. tksurfer loaded the file and displayed it correctly. I also used "mris_inflate" to blow out the calcarine sulcus. I cut off the occipital lobe with tksurfer and saved the patch. Then I tried "mris_flatten". I got this error message: mris_flatten: could not read surface file subject/xxx/surf/lh.smoothwm I don't have a white matter surface. Is there anyway to bypass lh.smoothwm? I imagined that once I have a inflated surface, flattening should be be a self-contained problem and does not require an additional surface. Why is mris_flatten looking for .smoothwm? Thanx. Hsin-Hao