Real-time simulations of networks of Hodgkin–Huxley neurons using analog circuits

The traditional dilemma for performing network simulations with analog circuits is the great difficulty of handling the connectivity in hardware. The main problem is that hardware-based connectivity must be built following predefined plasticity and connectivity rules, and that once the hardware is built, it is usually not possible to change its configuration. We show here an alternative system in which the membrane equations are solved in analog ASIC circuits, but the connectivity remains controlled by a digital computer. We illustrate the behavior of this system by comparing the analog simulations with traditional computer simulations of the same models.