Note

This page is a reference documentation. It only explains the function signature, and not how to use it. Please refer to the user guide for the big picture.

nilearn.datasets.fetch_atlas_aal

nilearn.datasets.fetch_atlas_aal(version='SPM12', data_dir=None, url=None, resume=True, verbose=1)[source]

Download and returns the AAL template for SPM 12.

This Deterministic atlas is the result of an automated anatomical parcellation of the spatially normalized single-subject high-resolution T1 volume provided by the Montreal Neurological Institute (MNI) (D. L. Collins et al., 1998, Trans. Med. Imag. 17, 463-468, PubMed).

For more information on this dataset’s structure, see AAL template for SPM 12[1], and Tzourio-Mazoyer et al.[2].

Warning

The integers in the map image (data.maps) that define the parcellation are not always consecutive, as is usually the case in Nilearn, and should not be interpreted as indices for the list of label names. In addition, the region IDs are provided as strings, so it is necessary to cast them to integers when indexing. For more information, refer to the fetcher’s description:

from nilearn.datasets import fetch_atlas_aal

atlas = fetch_atlas_aal()
print(atlas.description)
Parameters:
version{‘3v2’, ‘SPM12’, ‘SPM5’, ‘SPM8’}, default=’SPM12’

The version of the AAL atlas. Must be ‘SPM5’, ‘SPM8’, ‘SPM12’, or ‘3v2’ for the latest SPM12 version of AAL3 software.

data_dirpathlib.Path or str, optional

Path where data should be downloaded. By default, files are downloaded in a nilearn_data folder in the home directory of the user. See also nilearn.datasets.utils.get_data_dirs.

urlstr, default=None

URL of file to download. Override download URL. Used for test only (or if you setup a mirror of the data).

resumebool, default=True

Whether to resume download of a partly-downloaded file.

verboseint, default=1

Verbosity level (0 means no message).

Returns:
datasklearn.utils.Bunch

Dictionary-like object, keys are:

  • ‘maps’: str, path to nifti file containing the regions. The image has shape (91, 109, 91) and contains 117 unique integer values defining the parcellation in version SPM 5, 8 and 12, and 167 unique integer values defining the parcellation in version 3v2. Please refer to the main description to see how to link labels to regions IDs.

  • ‘labels’: list of str, list of the names of the regions. As ‘Background’ (label 0) is not included in this list, there are 116 names in version SPM 5, 8, and 12, and 166 names in version 3v2. Please refer to the main description to see how to link labels to regions IDs.

  • ‘indices’: list of str, indices mapping ‘labels’ to values in the ‘maps’ image. This list has 116 elements in version SPM 5, 8 and 12, and 166 elements in version 3v2. Since the values in the ‘maps’ image do not correspond to indices in labels, but rather to values in indices, the location of a label in the labels list does not necessary match the associated value in the image. Use the indices list to identify the appropriate image value for a given label (See main description above).

  • ‘description’: str, description of the atlas.

Warns:
DeprecationWarning

Starting in version 0.13, the default fetched mask will be AAL 3v2.

Notes

Licence: unknown.

References