1. A neural network comprising: an array of interconnected processors, each processor operating in either the pulse domain or spike domain, and each said processor having: first inputs selectively coupled to other processors in said array of interconnected processors, each first input having an associated 1 bit DAC coupled to a summing node, second inputs selectively coupled to inputs of the neural network, the second inputs having current generators associated therewith coupled to said summing node, a filter/integrator for generating an analog signal corresponding to current arriving at the summing node, if the processors operate in the pulse domain, an analog-to-pulse converter for converting an analog signal derived either directly from the filter/integrator or via a non-linear element, to the pulse domain, and providing the converted analog signal as an unquantized pulse domain signal at an output of each processor operating in the pulse domain; if the processors operate in the spike domain, an analog-to-spike converter for converting an analog signal derived either directly from the filter/integrator or via a non-linear element, to the spike domain, and providing the converted analog signal as an unquantized spike domain signal at an output of each processor operating in the spike domain; wherein the array of interconnected processors are selectively interconnected with either unquantized pulse domain or spike domain signals.