Neural Network Learning Algorithms

Abstract

The earliest network models of associative memory were based on correlations between input and output patterns of activity in linear processing units. These models have several features that make them attractive: The synaptic strengths are computed from information available locally at each synapse in a single trial; the information is distributed in a large number of connection strengths, the recall of stored information is associative, and the network can generalize to new input patterns that are similar to stored patterns. There are also severe limitations with this class of linear associative matrix models, including interference between stored items, especially between ones that are related, and inability to make decisions that are contingent on several inputs. New neural network models and neural network learning algorithms have been introduced recently that overcome some of the shortcomings of the associative matrix models of memory. These learning algorithms require many training examples to create the internal representations needed to perform a difficult task and generalize properly. They share some properties with human skill acquisition.