A programmable axonal propagation delay circuit for time-delay spiking neural networks

— we present an implementation of a programmable axonal propagation delay circuit which uses one first-order logdomain low-pass filter. Delays may be programmed in the 550ms range. It is designed to be a building block for time-delay spiking neural networks. It consists of a leaky-integrate-and-fire core, a spike generator circuit, and a delay adaptation circuit. I. BACKGROUND A number of observations suggest that the time-delays of neural spikes in the nervous system may be adaptive [1][2]. There are two general categories of delay adaptation. The first category we refer to as delay shift. In biology, it may be achieved by changing the length and thickness of dendrites and axons, the extent of myelination of axons, or the density and type of ion channels [3]. The second category, which we refer to as delay selection, supposes that a range of (random) delays are present in the beginning and during development appropriate subsets are pruned or selected [4]. Delay selection may be impl...

• Type: Journal
• Year: 2011
• Where: ISCAS
• Authors: Runchun Wang, Craig T. Jin, Alistair McEwan, André van Schaik
• Keywords: Dendrites And Axons, Hardware, ISCAS 2011, Propagation Delay, VLSI Implementation