Atlas of Lateralized visuospatial Attentional Networks (ALANs)

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In accordance with the SENSAAS, WMCA, and HAMOTA atlases, this repository introduces the ALANs atlas, which encompasses 95 specifically selected regions underpinning the anatomical and functional bases of visuo-spatial attention in humans.

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Reference

For usage of the manuscript, please cite:

• Labache, L., Petit, L., Joliot, & Zago, L. (2024). Atlas for the Lateralized Visuospatial Attention Networks (ALANs): Insights from fMRI and Network Analyses. DOI: 10.1162/imag_a_00208

For usage of the associated code, data, or visualization, please also cite:

• Labache, L., (2024). loiclabache/ALANs_brainAtlas: Atlas for the Lateralized Visuospatial Attention Networks (ALANs) (Labache_2024_ALANs_240214). Zenodo.DOI: 10.5281/zenodo.10658842

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Background

Hemispheric specialization is central to human evolution and fundamental to human cognitive abilities. While being a defining feature of functional brain architecture, hemispheric specialization is overlooked to derive brain parcellations. Alongside language, which is typically lateralized in the left hemisphere, visuospatial attention is set to be its counterpart in the opposite hemisphere. However, it remains uncertain to what extent the anatomical and functional underpinnings of lateralized visuospatial attention mirror those supporting language. Building on our previous work, which established a lateralized brain atlas for language, we propose a comprehensive cerebral lateralized atlas delineating the anatomo-functional bases of visuospatial attention, ALANs. Combining task and resting-state functional connectivity analyses, we identified 95 lateralized brain areas comprising five networks supporting visuospatial attention processes. Among them, we can find two large-scale networks: the Parieto-frontal and Temporo-frontal networks. We identify hubs playing a pivotal role in the intra-hemispheric interaction within visuospatial attentional networks. The rightward lateralized Parieto-frontal encompasses one hub, the inferior frontal sulcus, while the Temporo-frontal network encompasses two right hubs: the inferior frontal cortex (pars triangularis and the anterior insula) and the posterior part of the superior temporal sulcus. Together, these networks encompass the homotope of the language network from the left hemisphere. This atlas of visuospatial attention provides valuable insights for future investigations into the variability of visuospatial attention and hemispheric specialization research. Additionally, it facilitates more effective comparisons among different studies, thereby enhancing the robustness and reliability of research in the field of attention.

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Data release

The Atlas folder contains 4 files:

• read_me_ALANs.rtf: README file containing information. about the atlas
• ALANs_MNI_ICBM_152_2mm.nii.gz: NIfTI file containing the 95 brain regions in the MNI space.

• ALANs_description.txt: text file containing a full description of each regions. The first column Network corresponds to which of the 5 networks a region belongs. The second column Abbreviation is the abbreviation of a region. The third column Region is the full anatomical label of a region. Atlas_Homotopic indicates if a region belongs to the original atlas (showed as “Atlas”, one of the 95 regions selected in the paper) or if it is its counterpart in the opposite hemisphere (showed as “Homotopic”). Hemisphere refers to the cerebral hemisphere to which a region belongs. Index is the index of each region that is used in the NIfTI file. The MNI coordinate (columns Xmm, Ymm, Zmm) of each regions centroid is also provided. Number of Voxels and Volume mm3 are the number of voxels and the volume (in cubic millimetre) of each region for the 2mm version of the atlas. HEXA is the color of each region according to the AICHA atlas.

• template_ANTs_80tvs_on_MNI.nii.gz: brain template used to align the atlas on, provided in MNI stereotaxic space (MNI ICBM 152, Template sampling size of 2x2x2 mm3 voxels; bounding box, x = -90 to 90 mm, y = -126 to 91 mm, z = -72 to 109 mm).

The Data folder contains 3 files and 2 sub-folders:

• 130_participants_BOLD_LBJ_BILGIN.txt: brain activation of each participant for each region of the AICHA atlas during the LBJ (Line Bisection Judgment) task.

• 130_participants_BOLD_rs_BILGIN.Rds: resting-state connectivity matrices of the 95 ALANs regions for each participant.

• 130_participants_BOLD_rs_networks_BILGIN.csv: intrinsic correlation of the 5 ALANs networks for each participant.

• comparison_AICHA_Yan2023_400_2mm.csv: assignment of each region of the AICHA atlas to one of the seven canonical networks proposed by Yan and colleagues (2023, DOI: 10.1016/j.neuroimage.2023.120010).

• the sub-folder AICHA_v2 contains the file AICHA.nii corresponding to the version 2 (June 2021, MNI space, resolution of 2mm) of the AICHA atlas.

• the sub-folder Yan_2023_v0.28.3 contains two files. The first one: 400Parcels_Yeo2011_7Networks_FSLMNI152_2mm.nii.gz corresponding to the version 0.28.3 (MNI space, 400 parcels, 2mm) of the atlas proposed by Yan and colleagues (2023, DOI: 10.1016/j.neuroimage.2023.120010). The second file: 400Parcels_Yeo2011_7Networks_LUT.txt contains a full description of each regions of the atlas, including the assignment to the seven canonical networks proposed by Yeo and colleagues (2011, DOI: 10.1152/jn.00338.2011).

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Code release

The Script folder includes 4 R scripts. The R scripts are designed to facilitate the replication of results as detailed in the Method Section of the manuscript.

• 1_ROI_Selection.R: R script to select brain regions that are both significantly activated in the right hemisphere and rightward lateralized, and regions that are both significantly activated in the left hemisphere and leftward lateralized.
• 2_Rest_Classification_and_Metrics.R: R script to perform Agglomerative Hierarchical Classification on the average intrinsic connectivity matrix, to select the appropriate number of clusters, and to compute, for each participant and region, the Degree and the Betweenness Centrality.
• 3_Atlas_Comparison.R: R script for assigning each region of the AICHA atlas to one of the seven networks proposed by Yan and colleagues (2023, DOI: 10.1016/j.neuroimage.2023.120010). Version 2 (June 2021, MNI space, resolution of 2mm) of the AICHA atlas was used in this study. For the atlas proposed by Yan and colleagues (2023), version 0.28.3, featuring 400 parcels within the MNI space at a resolution of 2mm, was used.
• 4_SurfIce_Script_Generator.R: R script to generate a GLS file for use with Surf Ice to visualize brain atlases (ALANs or AICHA).
• 5_Temporal_Correlation_Networks.R: R script to compute average correlations between ALAN networks and test their significance.

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Other papers and atlases that might interest you

• The seminal paper describing the Line Bisection Judgment task: Zago, L., et al. 2016. DOI: 10.1016/j.neuropsychologia.2015.11.018
• SEntence Supramodal Areas AtlaS: SENSAAS
• Language-and-Memory atlas: L∪M
• Word-list Multimodal Cortical Atlas: WMCA
• HAnd MOtor Area atlas: HAMOTA
• Atlas of Intrinsic Connectivity of Homotopic Areas: AICHA

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Questions

Please contact me (Loïc Labache) as [email protected] and/or [email protected]