Connectionists: paper available on fast presynaptic noise on ANN

[J.M. Cortes]

Dear all,

I would like to announce  the following paper, that can be downloaded
from arxiv.org/pdf/q-bio.NC/0508013 and that will be published in Neural
Computation this year 2005.


Effects of fast presynaptic noise in attractor neural networks
J. M. Cortes, J. J. Torres, J. Marro, P. L. Garrido, H. J. Kappen
  

We study both analytically and numerically the effect of presynaptic noise
on the transmission of information in attractor neural networks. The noise
occurs on a very short-time scale compared to that for the neuron dynamics
and it produces short-time synaptic depression. This is inspired in recent
neurobiological findings that show that synaptic strength may either
increase or decrease on a short-time scale depending on presynaptic
activity. We thus describe a mechanism by which fast presynaptic noise
enhances the neural network sensitivity to an external stimulus. The
reason for this is that, in general, the presynaptic noise induces
nonequilibrium behavior and, consequently, the space of fixed points is
qualitatively modified in such a way that the system can easily scape from
the attractor. As a result, the model shows, in addition to pattern
recognition, class identification and categorization, which may be
relevant to the understanding of some of the brain complex tasks.


Jesus M. Cortes, PostDoctoral Researcher
SNN, Radboud University Nijmegen
The Netherlands                        
Tel. +31 243614230
Fax. +31 243541435