Note that this reference documentation is identical to the help that is displayed in MATLAB when you type “help ft_read_atlas”.

  FT_READ_ATLAS reads an template/individual segmentation or parcellation from disk.
  The volumetric segmentation or the surface-based parcellation can either represent
  a template atlas (eg. AAL or the Talairach Daemon), it can represent an
  individualized atlas (e.g. obtained from FreeSurfer) or it can represent an
  unlabeled parcellation obtained from the individual's DTi or resting state fMRI.
 
  Use as
    atlas = ft_read_atlas(filename, ...)
  or
    atlas = ft_read_atlas({filenamelabels, filenamemesh}, ...)
 
  Additional options should be specified in key-value pairs and can include
    'format'      = string, see below
    'unit'        = string, e.g. 'mm' (default is the native units of the file)
 
  For individual surface-based atlases from FreeSurfer you should specify two
  filenames as a cell-array: the first points to the file that contains information
  with respect to the parcels' labels, the second points to the file that defines the
  mesh on which the parcellation is defined.
 
  The output atlas will be represented as structure according to
  FT_DATATYPE_SEGMENTATION or FT_DATATYPE_PARCELLATION.
 
  The "lines" and the "colorcube" colormaps are useful for plotting the different
  patches, for example using FT_PLOT_MESH.
 
  See also FT_READ_MRI, FT_READ_HEADSHAPE, FT_PREPARE_SOURCEMODEL, FT_SOURCEPARCELLATE, FT_PLOT_MESH