Larger Connection Radius Increases Hub Astrocyte Number in a 3-D Neuron–Astrocyte Network Model

Astrocytes - a prominent glial cell type in the brain - form networks that tightly interact with the brain's neuronal circuits. Thus, it is essential to study the modes of such interaction if we aim to understand how neural circuits process information. Thereby, calcium elevations, the primary signal in astrocytes, propagate to the adjacent neighboring cells and directly regulate neuronal communication. It is mostly unknown how the astrocyte network topology influences neuronal activity. Here, we used a computational model to simulate planar and 3D neuron-astrocyte networks with varying topologies. We investigated the number of active nodes, the shortest path, and the mean degree. Furthermore, we applied a graph coloring analysis that highlights the network organization between different network structures. With the increase of the maximum distance between two connected astrocytes, the information flow is more centralized to the most connected cells. Our results suggest that activity-dependent plasticity and the topology of brain areas might alter the amount of astrocyte controlled synapses.