Towards cortex sized artificial neural systems

  • Authors:
  • Christopher Johansson;Anders Lansner

  • Affiliations:
  • Department of Numerical Analysis and Computer Science, Royal Institute of Technology, Stockholm, Sweden;Department of Numerical Analysis and Computer Science, Royal Institute of Technology, Stockholm, Sweden

  • Venue:
  • Neural Networks
  • Year:
  • 2007

Quantified Score

Hi-index 0.02

Visualization

Abstract

We propose, implement, and discuss an abstract model of the mammalian neocortex. This model is instantiated with a sparse recurrently connected neural network that has spiking leaky integrator units and continuous Hebbian learning. First we study the structure, modularization, and size of neocortex, and then we describe a generic computational model of the cortical circuitry. A characterizing feature of the model is that it is based on the modularization of neocortex into hypercolumns and minicolumns. Both a floating- and fixed-point arithmetic implementation of the model are presented along with simulation results. We conclude that an implementation on a cluster computer is not communication but computation bounded. A mouse and rat cortex sized version of our model executes in 44% and 23% of real-time respectively. Further, an instance of the model with 1.6x10^6 units and 2x10^1^1 connections performed noise reduction and pattern completion. These implementations represent the current frontier of large-scale abstract neural network simulations in terms of network size and running speed.