1. A neuronal network, comprising: a plurality of units, each having a memory and generating an event; a plurality of doublets, each doublet being connected to a pair of the plurality of units and configured to update a memory of the doublet and memory of a postsynaptic one of the pair of units according to a doublet event rule; wherein the doublet event rule for each doublet includes a timing event rule that controls update of the memory of the each doublet; the doublet event rule for each doublet includes pulse delivery rule that controls update of the memory of the postsynaptic one of the pair of units; and execution of doublet event rules for the plurality of doublets is order-independent.