= Use FreeSurfer cortical parcellation =
The free software !FreeSurfer can be used to extract brain and head  surfaces from a T1 MRI. It also automatically registers the individual  cortex surfaces to two atlases (Desikan-Killiany and Destrieux). The  results of those of those cortex segmentations can now be imported in  Brainstorm as scouts, and therefore be used as anatomical ROIs.

For more information about the methods involved and the software installation:

 * Cortical parcellation: http://freesurfer.net/fswiki/CorticalParcellation
 * !FreeSurfer Wiki: http://surfer.nmr.mgh.harvard.edu/fswiki/

== Import parcellations ==
 1. Process your subject MRI with the full !FreeSurfer T1 analysis pipeline
 1. In Brainstorm, create a protocol and a subject, as explained in the introduction tutorials
 1. Import the following files from the !FreeSurfer architecture:
  * MRI: /mri/T1.mgz
  * Head surface: /bem/wateshed/outer_skin_surface
  * Left hemisphere: /surf/lh.pial (or lh.smoothwm)
  * Right hemisphere: /surf/lh.pial (or lh.smoothwm)
 1. Add the atlas-based parcellations to each hemisphere <<BR>><<BR>>{{attachment:importAnnot1.gif}}
  * Right-click on "lh" > Labels > Import labels
  * Select one of the annotation files in the /label/ folder:
   * Destrieux atlas: lh.aparc.a2009s.annot
   * Desikan-Killiany atlas: lh.aparc.annot
  * Repeat the same operation for the right hemisphere
  * The .annot files are read with the !FreeSurfer read_annotation.m Matlab function, then converted to Brainstorm scouts, and saved in the surface files in the "Scout" field
 1. Downsample each hemisphere to 7500 vertices (the scouts will be downsampled accordingly)<<BR>>Right-click > Less vertices
 1. Concatenate the two downsampled surfaces<<BR>>Select lh_7500 and rh_7500 > right-click > Merge surfaces
 1. Rename the new surface into "cortex". This last surface contains all the scouts (ie. ROIs) defined for lh and rh, which will be loaded automatically when you display the surface in Brainstorm.
 1. Double-click on "cortex", go to the Scout tab, and select a few scouts, to check that the .annot files where imported properly<<BR>><<BR>>{{attachment:importAnnot2.gif}}

== Examples ==
Desikan-Killiany atlas, in !FreeSurfer:

{{attachment:dk_fs.jpg}}

Desikan-Killiany atlas, in Brainstorm:

{{attachment:dk_bs.jpg}}

Desikan-Killiany atlas, in Brainstorm after downsampling to 15000 vertices:

{{attachment:dk_bs2.gif}}

Destrieux atlas, in !FreeSurfer

{{attachment:de_fs.gif}}