Postclassification category use: The effects of learning to use categoriesafter learning to classify

The use of category knowledge can affect category representations, includin g classification knowledge, even if people learn to classify before learnin g to use the categories. In 5 experiments, subjects first learned to classi fy spy messages and then learned a category use that required simple proble m solving (applying a formula to decode a message). The number relations th at were important for the decoding were later used as an additional basis o f classification. This effect of category use occurred even when the classi fication was not provided during use learning, if the category representati on was incidentally available. This incidental activation of the category r epresentation is common in real-world situations and can occur by additiona l processing (Experiment 2) or by extended classification learning (Experim ents 3-5). The discussion focuses on the conditions necessary for obtaining this effect and the generality of the findings.