A silicon model of the Hirudo swim oscillator

Discusses using VLSI-based technology for recreating living neuronal circuits. The authors describe a study in which one subunit of the oscillatory network of the leech Hirudo medicinalis was reconstructed on a cell-by-cell, synapse-by-synapse basis using dedicated IC-based neural elements. The network consists of 11 cells in which 34 distinct multicellular oscillators are embedded. In functional tests, the circuit displayed rhythms and waveforms that closely resembled those of its living counterparts. In parametric tests, the network displayed remarkable robustness over a broad range of intracellular and synaptic parameters. From these tests, analysis of the network imparted insights into its design and function. The comprehensive nature of the neuronal element´s design and the efficiency afforded by very-large-scale-integrated (VLSI) technology has greatly facilitated the endeavour of modeling neuronal networks and processes in analog electronic circuitry.