Local Learning Algorithms for Sequential Tasks in Neural Networks

In this paper we explore the concept of sequential learning and the efficacy of global and local neural network learning algorithms on a sequential learning task. Pseudorehearsal (a method developed by Robins [19] to solve the catastrophic forgetting problem which arises from the excessive plasticity of neural networks) is significantly more effective than other local learning algorithms for the sequential task. We further consider the concept of local learning and suggest that pseudorehearsal is so effective because it works directly at the level of the learned function, and not indirectly on the representation of the function within the network. We also briefly explore the effect of local learning on generalisation within the task.