T1-weighted MPRAGE scans were parcellated and segmented into anatomical regions using recon-all program of the FreeSurfer (version 6.0; The General Hospital Corporation, Boston, MA). Image analysis in FreeSurfer has been previously described (Fischl and Dale, 2000). Briefly, after basic preprocessing, the white matter and pial surfaces were identified by creating a mesh around the white matter and pial voxels. Surface-based maps of each individual scan were constructed using a manually labeled training dataset (Desikan et al., 2006). The anatomical accuracy of FreeSurfer’s automated parcellations and segmentations were visually inspected. Finally, volumetric measurements for each cortical and subcortical region were obtained through automated calculation of the distances between their surface and white matter border using recon-all program.
