Methods and apparatus are provided for determining synapses in an artificial nervous system based on connectivity patterns. One example method generally includes determining, for an artificial neuron, an event has occurred; based on the event, determining one or more synapses with other artificial neurons based on a connectivity pattern associated with the artificial neuron; and applying a spike from the artificial neuron to the other artificial neurons based on the determined synapses. In this manner, the connectivity patterns (or parameters for determining such patterns) for particular neuron types, rather than the connectivity itself, may be stored. Using the stored information, synapses may be computed on the fly, thereby reducing memory consumption and increasing memory bandwidth. This also saves time during artificial nervous system updates.