AUTHOR=Reimann Michael W. , Nolte Max , Scolamiero Martina , Turner Katharine , Perin Rodrigo , Chindemi Giuseppe , Dłotko Paweł , Levi Ran , Hess Kathryn , Markram Henry TITLE=Cliques of Neurons Bound into Cavities Provide a Missing Link between Structure and Function JOURNAL=Frontiers in Computational Neuroscience VOLUME=11 YEAR=2017 URL=https://www.frontiersin.org/journals/computational-neuroscience/articles/10.3389/fncom.2017.00048 DOI=10.3389/fncom.2017.00048 ISSN=1662-5188 ABSTRACT=

The lack of a formal link between neural network structure and its emergent function has hampered our understanding of how the brain processes information. We have now come closer to describing such a link by taking the direction of synaptic transmission into account, constructing graphs of a network that reflect the direction of information flow, and analyzing these directed graphs using algebraic topology. Applying this approach to a local network of neurons in the neocortex revealed a remarkably intricate and previously unseen topology of synaptic connectivity. The synaptic network contains an abundance of cliques of neurons bound into cavities that guide the emergence of correlated activity. In response to stimuli, correlated activity binds synaptically connected neurons into functional cliques and cavities that evolve in a stereotypical sequence toward peak complexity. We propose that the brain processes stimuli by forming increasingly complex functional cliques and cavities.