Period Doubling as a Means of Representing Multiply Instantiated Entities

The problem of multiple instantiation is the ability to handle different instances of a unique object at the same time. For connectionist models that do not use a working area containing copies of items from a long-term knowledge base, the problem of multiple instantiation is a particularly difficult one. While people are able to deal with multiple instances, their performance when doing so is nonetheless poorer, which is not the case for symbolic models. A cognitive model should reflect competence, as well as its limits. Some connectionist solutions to the problem of multiple instantiation are mentioned in this paper. An new solution which makes use of semi-distributed representations is presented. This model does not separate the long term knowledge base from a working area and has no recourse to copies. This solution limits the process of multiple instantiation in a way that should better reflect human data.