Continuous attractor neural networks (CANNs) Thomas P. Trappenberg Dalhousie University, Canada CANN models and their relation to ANN Phase transitions in the weight-parameter space Hebbian learning and dimensionality discovery Path-integration Drifting activity packets and NMDA stabilization ?
`Basic/standard’ Grossberg-Hopfield type recurrent networks or spiking versions
`Basic/standard’ CANNmodel
Activity packet
Phase transitions in the weight-parameter space
Various gain functions
( or … ) Hebbian Learning Training on Gaussian patterns: Also, Kechen Zhang ’96: Gradient decent training …
Dimensionality discovery
Path-integration
Continuous dynamic (leaky integrator): The model equations: Continuous dynamic (leaky integrator): : activity of node i : firing rate : synaptic efficacy matrix : global inhibition : visual input : time constant : scaling factor : #connections per node : slope : threshold NMDA-style stabilization: Hebbian learning:
Drifting activity packets NMDA stabilization: