This work was supported by NSF: NeuroNex Grant #2015317 to RQ, AH, and NS funds research into creating computational and roboticmodels of animalmotor control, NSF: RI Grant #1704436 to RQ funds research into tuning dynamical neural controllers for legged robots, and NSF: US-German Collaboration Grant #1608111 to RQ funds research into tuning dynamical neural controllers for legged robots.
Frontiers in Neurorobotics
Neural networks (Computer science), Neural networks (Neurobiology), Neurons -- Mathematical models
Engineering neural networks to perform specific tasks often represents a monumental challenge in determining network architecture and parameter values. In this work, we extend our previously-developed method for tuning networks of non-spiking neurons, the “Functional subnetwork approach” (FSA), to the tuning of networks composed of spiking neurons. This extension enables the direct assembly and tuning of networks of spiking neurons and synapses based on the network’s intended function, without the use of global optimization ormachine learning. To extend the FSA, we show that the dynamics of a generalized linear integrate and fire (GLIF) neuronmodel have fundamental similarities to those of a non-spiking leaky integrator neuron model.We derive analytical expressions that show functional parallels between: (1) A spiking neuron’s steady-state spiking frequency and a non-spiking neuron’s steady-state voltage in response to an applied current; (2) a spiking neuron’s transient spiking frequency and a non-spiking neuron’s transient voltage in response to an applied current; and (3) a spiking synapse’s average conductance during steady spiking and a non-spiking synapse’s conductance. The models become more similar as additional spiking neurons are added to each population “node” in the network. We apply the FSA to model a neuromuscular reflex pathway two different ways: Via non-spiking components and then via spiking components. These results provide a concrete example of how a single non-spiking neuron may model the average spiking frequency of a population of spiking neurons. The resulting model also demonstrates that by using the FSA, models can be constructed that incorporate both spiking and non-spiking units. This work facilitates the construction of large networks of spiking neurons and synapses that perform specific functions, for example, those implemented with neuromorphic computing hardware, by providing an analytical method for directly tuning their parameters without time-consuming optimization or learning.
Copyright © 2020 Szczecinski, Quinn and Hunt. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
Szczecinski NS, Quinn RD and Hunt AJ (2020) Extending the Functional Subnetwork Approach to a Generalized Linear Integrate-and-Fire Neuron Model. Front. Neurorobot. 14:577804. doi: 10.3389/fnbot.2020.577804