Connectivity matrices

Instead of offering a bewildering number of options for constructing connectivity matrices, qsirecon will construct as many connectivity matrices as it can given the reconstruction methods. It is highly recommended that you pick a weighting scheme before you run these pipelines and only look at those numbers. If you look at more than one weighting method be sure to adjust your statistics for the additional comparisons.

Atlases

The following atlases are included in qsirecon and are used by default in the preconfigured_workflows. If you use one of them please be sure to cite the relevant publication.

  • schaefer100, schaefer200, schaefer400: Schaefer et al.[1], Yeo et al.[2]

  • brainnetome246: Fan et al.[3]

  • aicha384: Joliot et al.[4]

  • gordon333: Gordon et al.[5]

  • aal116: Tzourio-Mazoyer et al.[6]

Using custom atlases

It’s possible to use your own atlases provided you can match the format qsirecon uses to read atlases. The qsirecon atlas set can be downloaded directly from box.

In this directory there must exist a JSON file called atlas_config.json containing an entry for each atlas you would like included. The format is:

{
  "my_custom_atlas": {
    "file": "file_in_this_directory.nii.gz",
    "node_names": ["Region1_L", "Region1_R" ... "RegionN_R"],
    "node_ids": [1, 2, ..., N]
  }
  ...
}

Where "node_names" are the text names of the regions in "my_custom_atlas" and "node_ids" are the numbers in the nifti file that correspond to each region. When custom_reconstruction you can then inclued "my_custom_atlas" in the "atlases":[] section.

The directory containing atlas_config.json and the atlas nifti files should be mounted in the container at /atlas/qsirecon_atlases. If using qsirecon-docker or qsirecon-singularity this can be done with --custom-atlases /path/to/my/atlases or if you’re running on your own system (not recommended) you can set the environment variable QSIRECON_ATLAS=/path/to/my/atlases.

The nifti images should be registered to the MNI152NLin2009cAsym included in qsirecon. It is essential that your images are in the LPS+ orientation and have the sform zeroed-out in the header. Be sure to check for alignment and orientation in your outputs.

References