Modeling cortical function starting with minimal connectivity

Neural models of cortical function frequently assume initial profuse connectivity and ignore issues of cortical development. There is increasing interest in cortical models that minimise pre-specification of architecture and instead allow input and learning rules to sculpt connectivity. We describe a model of cortical development that begins with minimal connectivity but arrives at useful functionality through a variety of mechanisms, including Hebbian learning, volume learning, synaptic sprouting and structured input. We discuss some of the issues pertinent to the building of neural structure.