Role of inter-hemispheric connections in functional brain networks

Area of Science:

• Neuroscience
• Network Science
• Computational Biology

Background:

• The human brain is increasingly modeled as a complex network of interacting regions.
• Brain function is thought to emerge from the coordinated activity of specialized sub-networks.
• Understanding inter-sub-network communication is crucial for deciphering brain dynamics.

Purpose of the Study:

• To model the brain as an interconnected system of two competing sub-networks: the left and right hemispheres.
• To investigate how inter-hemispheric connections influence topological centrality within functional scalp EEG networks (SEN).
• To analyze the impact of node failure on hemispheric centrality and functional balance.

Main Methods:

• Analysis of functional scalp EEG networks (SEN) derived from high-density electroencephalographic (EEG) recordings.
• Topological analysis of node centrality and its dependence on inter-hemispheric connectivity.
• Simulation of node failure to assess network robustness and hemispheric balance.

Main Results:

• Hemispheric centrality distribution is significantly shaped by the number and distribution of inter-hemispheric functional connections.
• The abundance of inter-hemispheric links promotes a balanced distribution of centrality between the left and right hemispheres.
• Node failure impacts hemispheric centrality, with more inter-hemispheric links leading to greater functional balance.

Conclusions:

• Inter-hemispheric connectivity plays a critical role in shaping the functional network topology and centrality of brain hemispheres.
• A robust network of inter-hemispheric connections ensures functional balance and resilience against node failure.
• This network-of-networks (NoN) approach provides insights into brain dynamics and hemispheric specialization.