Contributions of category and fine-grained information to location memory: when categories don't weigh in.

Several studies have shown that people's memory for location can be influenced by categorical information. According to a model proposed by Huttenlocher, Hedges, and Duncan (1991), people estimate location by combining fine-grained item-level information in memory with category-level information. When the fine-grained information is inexact, category-level information is given greater weight, which leads to biased responses. We manipulated the distribution of locations presented in order to alter the usefulness of category information, and we manipulated background texture in order to alter accuracy of fine-grained memory. The distributional information reduced bias without altering overall accuracy of responding, whereas the background texture manipulation affected accuracy without changing bias. Our results suggest that category information may weigh in only when it is actively processed.