TR available:Synchronization in Dynamic Neural Networks

[Dr L S Smith (Staff)]

***DO NOT FORWARD TO OTHER GROUPS***


University of Stirling, Centre for Cognitive and Computational 
Neuroscience, Stirling FK9 4LA, Scotland

CCCN Technical report CCCN-18 (Ph.D. Thesis)

Synchronization in Dynamic Neural Networks

David E. Cairns

This thesis is concerned with the function and implementation of 
synchronization in networks of oscillators.
Evidence for the existence of synchronization in cortex is reviewed
and a suitable architecture for exhibiting synchronization is 
defined. A number of factors which affect the performance of
synchronization in networks of laterally coupled oscillators
are investigated. It is shown that altering the strength of the lateral 
connections between nodes and altering the connective scope of a
network can be used to improve synchronization performance. It is
also shown that complete connective scope is not required for global
synchrony to occur.
The effects of noise on synchronization performance are also investigated
and it is shown that where an oscillator network is able to synchronize
effectively, it will also be robust to a moderate level of noise
in the lateral connections. Where a particular oscillator model shows
poor synchronization performance, it is shown that noise in the
lateral connections is capable of improving synchronization performance.

A number of applications of synchronizing oscillator networks are
investigated. The use of synchronized oscillations to encode global
binding information is investigated and the relationship between the
form of grouping obtained and connective scope is discussed. The 
potential for using learning in synchronizing oscillator
networks is illustrated and an investigation is made into the possibility
of maintaining multiple phases in a network of synchronizing 
oscillators. It is concluded from these investigations that
it is difficult to maintain multiple phases in the network 
architecture used throughout this thesis and a modified
architecture capable of producing the required behaviour is demonstrated.


This report is available by anonymous FTP from

ftp.cs.stir.ac.uk
(139.153.254.29)

in the directory

pub/tr/cccn

The filename is

TR18.ps.Z

(and, as usual, this needs transferred in binary mode, decompress'd, and the
 postscript printed.)

The decompressed file is 13.0 Mb long, and the printed document 100 pages.

Hard Copies may be made available for a price (unfortunately, our
budget does not run to free copies of theses) Due to the thesis containing grey-level illustrations, it does not photocopy well. If  necessary. Email 
lss at cs.stir.ac.uk.