Memory & Cognition

, Volume 8, Issue 4, pp 378–382 | Cite as

Differential forgetting of prototypes and old instances: Simulation by an exemplar-based classification model

  • Douglas L. Hintzman
  • Genevieve Ludlam


A common finding in studies of classification learning is that ability to classify the prototype of a category declines much less over a retention interval than does the ability to classify the previously seen exemplars themselves. We demonstrate here that this finding does not necessarily indicate the existence, in memory, of a representation of the prototype. MINERVA, a computer-simulation model that encodes memory traces only of presented exemplars, was tested on an appropriate task. Differential forgetting of prototypes and old instances was shown by a version of the model that assumed that (1) classification is based on the exemplar trace most similar to the test stimulus and (2) individual properties are lost from the traces over time in an all-or-none fashion. It is suggested that, in general, the key to the prediction of differential forgetting may be the concomitance of forgetting and generalization.


Test Stimulus Retention Interval Journal ofExperimental Psychology Memory Trace Generalization Gradient 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Psychonomic Society, Inc. 1980

Authors and Affiliations

  • Douglas L. Hintzman
    • 1
  • Genevieve Ludlam
    • 1
  1. 1.Psychology DepartmentUniversity of OregonEugene

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