Definitions of network connectivity.

<p>Illustration of different connectivity measures for a synaptic network connecting neuron populations to (which may be identical for recurrent networks). <b>A, </b><i>Anatomical connectivity </i> and <i>potential connectivity </i> are fractions of neuron pairs connected by an actual (black circles) and potential synapse (blue rectangles), respectively. <b>B,</b> The <i>consolidation signal </i> specifies the ensemble of neuron pairs that request a synapse (, red circles) to support storage of a given memory set. The corresponding <i>effectual connectivity </i> is then the fraction of neuron pairs requesting a synapse that are already connected by an actual synapse. The <i>consolidation load </i> is the fraction of neuron pairs that request a synapse.