What is learned in knowledge-related categories? Evidence from typicality and feature frequency judgments

When a category's features are tied together by integrative knowledge, subj ects learn the category faster than when the features are not directly rela ted. What do subjects learn about the category in such circumstances? Some research has suggested that the subjects can use the knowledge itself in pe rforming the category learning task and, thus, do not learn the details of the category's features. Two experiments investigated this hypothesis by co llecting feature frequency estimates after category learning. The results s howed that integrative knowledge about a category did not decrease subjects ' sensitivity to feature frequency-if anything, knowledge improved it. A th ird experiment found that integrative knowledge did reduce sensitivity to f eature frequency in typicality ratings. The results suggest that knowledge does not inhibit the learning of detailed category information, though it m ay replace its use in some tasks.