title: The role of dimensionality in neuronal network dynamics.
abstract: Recent results from network theory show that complexity affects several dynamical properties of networks that favor synchronization. Here we show that synchronization in 2D and 3D neuronal networks is significantly different. Using dissociated hippocampal neurons we compared properties of cultures grown on a flat 2D substrates with those formed on 3D graphene foam scaffolds. Both 2D and 3D cultures had comparable glia to neuron ratio and the percentage of GABAergic inhibitory neurons. 3D cultures because of their dimension have many connections among distant neurons leading to small-world networks and their characteristic dynamics. After one week, calcium imaging revealed moderately synchronous activity in 2D networks, but the degree of synchrony of 3D networks was higher and had two regimes: a highly synchronized (HS) and a moderately synchronized (MS) regime. The HS regime was never observed in 2D networks. During the MS regime, neuronal assemblies in synchrony changed with time as observed in mammalian brains. After two weeks, the degree of synchrony in 3D networks decreased, as observed in vivo. These results show that dimensionality determines properties of neuronal networks and that several features of brain dynamics are a consequence of its 3D topology.
authors.affiliation: Neurobiology Sector, International School for Advanced Studies (SISSA), via Bonomea, 265, 34136 Trieste, Italy.
authors.forename: Francesco Paolo
authors.initials: FP
authors.lastname: Ulloa Severino
authors.affiliation: Neurobiology Sector, International School for Advanced Studies (SISSA), via Bonomea, 265, 34136 Trieste, Italy.
authors.forename: Jelena
authors.initials: J
authors.lastname: Ban
authors.affiliation: Key Laboratory of Nano-Bio Interface, Suzhou Institute of Nano-tech and Nano-bionics, Chinese Academy of Sciences, 398 Ruoshui Road, Jiangsu 215123, China.
authors.forename: Qin
authors.initials: Q
authors.lastname: Song
authors.affiliation: Institute of Life Sciences, Southeast University, Sipailou 2, Nanjing 210096, China.
authors.forename: Mingliang
authors.initials: M
authors.lastname: Tang
authors.affiliation: School of Mathematical Sciences, Queen Mary University of London, Mile End Rd, London E1 4NS, United Kingdom.
authors.forename: Ginestra
authors.initials: G
authors.lastname: Bianconi
authors.affiliation: Key Laboratory of Nano-Bio Interface, Suzhou Institute of Nano-tech and Nano-bionics, Chinese Academy of Sciences, 398 Ruoshui Road, Jiangsu 215123, China.
authors.forename: Guosheng
authors.initials: G
authors.lastname: Cheng
authors.affiliation: Neurobiology Sector, International School for Advanced Studies (SISSA), via Bonomea, 265, 34136 Trieste, Italy.
authors.forename: Vincent
authors.initials: V
authors.lastname: Torre