M. Shiino et T. Fukai, ONSET OF SUPER RETRIEVAL PHASE AND ENHANCEMENT OF THE STORAGE CAPACITY IN NEURAL NETWORKS OF NONMONOTONIC NEURONS, Journal of physics. A, mathematical and general, 26(17), 1993, pp. 831-841
Analogue neural networks of associative memory with continuous time dy
namics are studied for hon-monotonic transfer functions using the meth
od of self-consistent signal-to-noise analysis. The Hebb learning rule
with unbiased random patterns is assumed for the synaptic couplings.
A novel phenomenon is found to occur as a result of a phase transition
concerning the property of the local field distribution. In retrieval
states of the newly found phase which we refer to as the super retrie
val phase, noise in the local fields vanishes and the memory retrieval
without errors ensues even for an extensive number of memory patterns
stored under the local learning rule. The storage capacity is obtaine
d as a function of the parameter representing the degree of non-monoto
nicity of the transfer functions, with the result that an enhancement
of the storage capacity can also occur.