  We investigate states of enhanced activity in a biological neuronal network
composed of pulse-coupled oscillators. The synaptic couplings between the
neurons are dynamic, modeling spike time dependent plasticity. The network
exhibits statistical characteristics which recently have been identified in an
analysis of epileptic seizures [Osorio et al., Phys. Rev. E 82, 021919(2010)]
based on analogies to the onset of earth quakes.
