A Look at Learning in Repeated Search: The Role of Memory and Competition

Abstract

The role of memory in repeated search tasks is contentious. Wolfe et al. (2000) have argued that participants do not learn a repeated scene and continue to perform a time-consuming search process for hundreds of trials. In contrast, Chun and Jiang (1998, 1999) have shown that search efficiency is improved for repeated versus new scenes and this learning can occur for either spatial layout independent of identity or identity independent of spatial layout. The experiments presented here demonstrate that participants learn a great deal about repeated search displays including the location of a particular item (both identity and location), the relative probability with which an item occurs in a location, and direction from the fixation point to the target. I argue that memory is established for these components and the reactivation of these memories by a repeated search display produces competition. This competitive target verification process takes time and can result in positive search slopes, which have been taken as evidence for memory-free search - a flawed logical argument.