Figure 3. Complexity of the structure carrying information depends on the percentage of inhibitory synapses.

Backbone carrying information for one configuration with N = 40 neurons learning the AND and XOR rules with different p_in. Neurons involved in avalanches giving the right answer to both rules are listed according to their firing time (downwards arrow). Input (output) neurons are green (black) and excitatory (inhibitory) neurons are red (blue). Neuron size is proportional to k_in. The three-digit number associated to each neuron is composed by the firing time followed by the neuron label (two digits). Long-range links appear if the post-synaptic neuron fires some time steps after receiving the stimulation from the pre-synaptic neuron.