Dear Freesurfer users,<br><br>I am wondering how are the volumes calculated from stats such aseg.stat.&nbsp; When I export the aseg and do a voxel count and multiple the volume per voxel, my total volume is different from that is given by the stats.&nbsp; For example, the hippocampal volume given by aseg.stats for one of my controls is 4000 cm3, but when I export the aseg.mgz into matlab and do a voxel count (my original voxel volume is 1mm3 isotropic) for that labeled mask, the total volume is aorund 3000 cm3.&nbsp; Does freesurfer does some sort of intensity normalization or partial volume correction?&nbsp; Even if so, the magnitude of difference is large that I am puzzled.<br><br>Thank you very much.<br>