We study the effects of reshulling of connections on collective dynamics.
We start from a leaky Integrate-and-Fire model whose connectivity was initially
designed in such a manner as to favor the spontaneous emergence of
collective oscillatory spatiotemporal patterns of spikes and we reshuffle all the
connections. For each chosen connection we change the presynaptic
neuron, choosing as the new presynaptic neuron a random neuron of the
network. After reshuffling the connections, not only the number of
excitatory and inhibitory connections is the same as before, but also
all the strengths of the connections are the same, and only the
topology is changed. We observe that reshuffling the connections
changes the features of the dynamics dramatically. Before reshuffling
the system has a transition from a regime of Poissonian noisy activity
to a regime of spontaneous persistent collective replay, and at the
transition point the network dynamics shows an intermittent
reactivation of the stored patterns, with alternation of up and down
states, and bimodal distribution of spiking rate. Reshuffling all the
connections we observe that the transition region with bimodal
distribution disappears, and the dynamics is Poissonian with unimodal
rate distribution for all the parameters investigated. These results
show the role of topology in dictating the emerging collective
dynamics of neural circuits.