K-shell decomposition reveals hierarchical cortical organization of the human brain
In recent years numerous attempts to understand the human brain were undertaken from a network point of view. A network framework takes into account the relationships between the different parts of the system and enables to examine how global and complex functions might emerge from network topology....
| Main Authors: | , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
IOP Publishing
2016-01-01
|
| Series: | New Journal of Physics |
| Subjects: | |
| Online Access: | https://doi.org/10.1088/1367-2630/18/8/083013 |
| _version_ | 1797750965158281216 |
|---|---|
| author | Nir Lahav Baruch Ksherim Eti Ben-Simon Adi Maron-Katz Reuven Cohen Shlomo Havlin |
| author_facet | Nir Lahav Baruch Ksherim Eti Ben-Simon Adi Maron-Katz Reuven Cohen Shlomo Havlin |
| author_sort | Nir Lahav |
| collection | DOAJ |
| description | In recent years numerous attempts to understand the human brain were undertaken from a network point of view. A network framework takes into account the relationships between the different parts of the system and enables to examine how global and complex functions might emerge from network topology. Previous work revealed that the human brain features ‘small world’ characteristics and that cortical hubs tend to interconnect among themselves. However, in order to fully understand the topological structure of hubs, and how their profile reflect the brain’s global functional organization, one needs to go beyond the properties of a specific hub and examine the various structural layers that make up the network. To address this topic further, we applied an analysis known in statistical physics and network theory as k-shell decomposition analysis. The analysis was applied on a human cortical network, derived from MRI\DSI data of six participants. Such analysis enables us to portray a detailed account of cortical connectivity focusing on different neighborhoods of inter-connected layers across the cortex. Our findings reveal that the human cortex is highly connected and efficient, and unlike the internet network contains no isolated nodes. The cortical network is comprised of a nucleus alongside shells of increasing connectivity that formed one connected giant component, revealing the human brain’s global functional organization. All these components were further categorized into three hierarchies in accordance with their connectivity profile, with each hierarchy reflecting different functional roles. Such a model may explain an efficient flow of information from the lowest hierarchy to the highest one, with each step enabling increased data integration. At the top, the highest hierarchy (the nucleus) serves as a global interconnected collective and demonstrates high correlation with consciousness related regions, suggesting that the nucleus might serve as a platform for consciousness to emerge. |
| first_indexed | 2024-03-12T16:40:29Z |
| format | Article |
| id | doaj.art-66354ad40ce245a68f8bb0cec21e70f6 |
| institution | Directory Open Access Journal |
| issn | 1367-2630 |
| language | English |
| last_indexed | 2024-03-12T16:40:29Z |
| publishDate | 2016-01-01 |
| publisher | IOP Publishing |
| record_format | Article |
| series | New Journal of Physics |
| spelling | doaj.art-66354ad40ce245a68f8bb0cec21e70f62023-08-08T14:31:50ZengIOP PublishingNew Journal of Physics1367-26302016-01-0118808301310.1088/1367-2630/18/8/083013K-shell decomposition reveals hierarchical cortical organization of the human brainNir Lahav0Baruch Ksherim1Eti Ben-Simon2https://orcid.org/0000-0002-3862-8288Adi Maron-Katz3Reuven Cohen4Shlomo Havlin5Department of Physics, Bar-Ilan University, Ramat Gan, IsraelDepartment of Physics, Bar-Ilan University, Ramat Gan, IsraelSackler Faculty of Medicine, Tel Aviv University , Tel-Aviv, Israel; Functional Brain Center, Wohl Institute for Advanced Imaging, Tel-Aviv Sourasky Medical Center, Tel- Aviv, IsraelSackler Faculty of Medicine, Tel Aviv University , Tel-Aviv, Israel; Functional Brain Center, Wohl Institute for Advanced Imaging, Tel-Aviv Sourasky Medical Center, Tel- Aviv, IsraelDepartment of Mathematics, Bar-Ilan University , Ramat Gan, IsraelDepartment of Physics, Bar-Ilan University, Ramat Gan, IsraelIn recent years numerous attempts to understand the human brain were undertaken from a network point of view. A network framework takes into account the relationships between the different parts of the system and enables to examine how global and complex functions might emerge from network topology. Previous work revealed that the human brain features ‘small world’ characteristics and that cortical hubs tend to interconnect among themselves. However, in order to fully understand the topological structure of hubs, and how their profile reflect the brain’s global functional organization, one needs to go beyond the properties of a specific hub and examine the various structural layers that make up the network. To address this topic further, we applied an analysis known in statistical physics and network theory as k-shell decomposition analysis. The analysis was applied on a human cortical network, derived from MRI\DSI data of six participants. Such analysis enables us to portray a detailed account of cortical connectivity focusing on different neighborhoods of inter-connected layers across the cortex. Our findings reveal that the human cortex is highly connected and efficient, and unlike the internet network contains no isolated nodes. The cortical network is comprised of a nucleus alongside shells of increasing connectivity that formed one connected giant component, revealing the human brain’s global functional organization. All these components were further categorized into three hierarchies in accordance with their connectivity profile, with each hierarchy reflecting different functional roles. Such a model may explain an efficient flow of information from the lowest hierarchy to the highest one, with each step enabling increased data integration. At the top, the highest hierarchy (the nucleus) serves as a global interconnected collective and demonstrates high correlation with consciousness related regions, suggesting that the nucleus might serve as a platform for consciousness to emerge.https://doi.org/10.1088/1367-2630/18/8/083013network theoryk-shell decompositioncortical hubsgraph theorymodular hierarchies in the brainhuman brain |
| spellingShingle | Nir Lahav Baruch Ksherim Eti Ben-Simon Adi Maron-Katz Reuven Cohen Shlomo Havlin K-shell decomposition reveals hierarchical cortical organization of the human brain New Journal of Physics network theory k-shell decomposition cortical hubs graph theory modular hierarchies in the brain human brain |
| title | K-shell decomposition reveals hierarchical cortical organization of the human brain |
| title_full | K-shell decomposition reveals hierarchical cortical organization of the human brain |
| title_fullStr | K-shell decomposition reveals hierarchical cortical organization of the human brain |
| title_full_unstemmed | K-shell decomposition reveals hierarchical cortical organization of the human brain |
| title_short | K-shell decomposition reveals hierarchical cortical organization of the human brain |
| title_sort | k shell decomposition reveals hierarchical cortical organization of the human brain |
| topic | network theory k-shell decomposition cortical hubs graph theory modular hierarchies in the brain human brain |
| url | https://doi.org/10.1088/1367-2630/18/8/083013 |
| work_keys_str_mv | AT nirlahav kshelldecompositionrevealshierarchicalcorticalorganizationofthehumanbrain AT baruchksherim kshelldecompositionrevealshierarchicalcorticalorganizationofthehumanbrain AT etibensimon kshelldecompositionrevealshierarchicalcorticalorganizationofthehumanbrain AT adimaronkatz kshelldecompositionrevealshierarchicalcorticalorganizationofthehumanbrain AT reuvencohen kshelldecompositionrevealshierarchicalcorticalorganizationofthehumanbrain AT shlomohavlin kshelldecompositionrevealshierarchicalcorticalorganizationofthehumanbrain |