Simulated Activation Patterns of Biological Neurons Cultured onto a Multi-Electrode Array Based on a Modified Izhikevich's Model

Abstract

Recently we have witnessed research efforts into developing real-time hybrid systems implementing interactions between computational models and live tissues, in an attempt to learn more about the functioning of biological neural networks. A fundamental role in the development of such systems is played by Multi-Electrode Array (MEA). In vitro cultures of neurons on MEAs, however, have some drawbacks such as: needing a rigorous adherence to sterile techniques, careful choice and replenishment of media and maintenance of pH, temperature, and osmolarity. An alternative way to study and investigate live tissues which partially circumvent some of the problems with in vitro cultures is by simulating them. This paper describes the proposal of Sim-MEA, a system for modeling and simulating neuron's communications in a MEA-based in vitro culture. Sim-MEA implements a modified Izhikevich model that takes into account both: distances between neurons and distances between microelectrodes and neurons. The system also provides ways of simulating microelectrodes and their recorded signals as well as recovering experimental MEA culture data, from their images. The soundness of the Sim-MEA simulation procedure was empirically evaluated using data from an experimental in vitro cultured hippocampal neurons of Wistar rat embryos. Results from simulations, compared to those of the in vitro experiment, are presented and discussed. The paper also describes a few experiments (varying several parameter values) to illustrate and detail the approach.