Uncovering the Morphological Evolution of Language-Relevant Brain Areas

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Results Folder

The ./results folder contains the main results derived from our study.

Probabilistic Atlas of the Chimpanzee BA44 and BA45

The folder ./results/chimpanzee-atlas contains the probabilistic atlas of cytoarchitectural regions BA44 and BA45 in the chimpanzee template (JUNA).

Projection of the Chimpanzee BA44 and BA45 to the Human Brain

The folder ./results/human-comparison contains the following information projected to the MNI surface:

1. The atlases of chimpanzee BA44 and BA45.
2. The atlases of human BA44 and BA45 [1].
3. The functional subdivisions of human BA44 defined by Clos et al. [2] and Papitto et al. [3].

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Scripts Folder

The ./scripts folder contains the scripts used for computing the results from our paper.

Chimpanzee Atlas Creation

The pipeline used to reconstruct the individual surface, composed by 4 steps:

1. Preprocessing the individual volumes.
2. Processing the individual volumes with Freesurfer.
3. Transforming the surfaces to the GIFTI format (compatible with the Connectome Workbench).
4. Translating the individual surfaces to the JUNA template space, and averaging them to obtain the atlas.

Human Comparison

The pipeline used to compare the chimpanzee Broca's atlas with human Broca and its functional subdivisions.

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References

[1] Amunts K, Schleicher A, Bürgel U, Mohlberg H, Uylings HB, Zilles K. Broca’s region revisited: cytoarchitecture and intersubject variability. J Comp Neurol. 1999;412: 319–341.

[2] Clos M, Amunts K, Laird AR, Fox PT, Eickhoff SB. Tackling the multifunctional nature of Broca’s region meta-analytically: co-activation-based parcellation of area 44. Neuroimage. 2013;83: 174–188.

[3] Papitto G, Friederici AD, Zaccarella E. The topographical organization of motor processing: An ALE meta-analysis on six action domains and the relevance of Broca’s region. Neuroimage. 2020;206: 116321.