  We observe and study a self-organized phenomenon whereby the activity in a
network of spiking neurons spontaneously terminates. We consider different
types of populations, consisting of bistable model neurons connected
electrically by gap junctions, or by either excitatory or inhibitory synapses,
in a scale-free connection topology. We find that strongly synchronized
population spiking events lead to complete cessation of activity in excitatory
networks, but not in gap junction or inhibitory networks. We identify the
underlying mechanism responsible for this phenomenon by examining the
particular shape of the excitatory postsynaptic currents that arise in the
neurons. We also examine the effects of the synaptic time constant, coupling
strength, and channel noise on the occurrence of the phenomenon.
