RT Journal Article SR Electronic T1 The emergence of dynamical instantaneous memory in the spontaneous activity of spatially confined neuronal assemblies in vitro JF bioRxiv FD Cold Spring Harbor Laboratory SP 412320 DO 10.1101/412320 A1 Y. Piasetzky A1 M. Bisio A1 S. Kanner A1 M Goldin A1 M. Olivenbaum A1 E. Ben-Jacob A1 Y Hanein A1 M. Chiappalone A1 A. Barzilai A1 P. Bonifazi YR 2018 UL http://biorxiv.org/content/early/2018/09/10/412320.abstract AB Understanding the dynamics between communicating cell assemblies is essential for deciphering the neural code and identifying the mechanism underlying memory formation. In this work, in order to unveil possible emergent intrinsic memory phenomena in the communication between cell assemblies, we study the spontaneous dynamics of in vitro spatially confined inter-connected neuronal circuits grown on multi-electrode arrays. The spontaneous dynamics of the global network was characterized by the coupling of the activity independently generated by each circuit. The asymptotic functional connectivity of the network reflected its modular organization. Instantaneous functional connectivity maps on ten seconds epochs, revealed more complex dynamical states with the simultaneous activation of distinct circuits. When looking at the similarity of the generated network events, we observed that spontaneous network events occurring at temporal distances below two dozens of seconds had an average higher similarity compared to randomly played network events. Such a memory phenomenon was not observed in networks where spontaneous events were less frequent and in networks topologically organized as open lines. These results support the hypothesis that dynamical instantaneous memory, characterized by drifting network dynamics with decaying degree of similarity, is an intrinsic property of neuronal networks.