The role of representational volatility in recognizing pre- and postchange objects.

Theories relating attention to change blindness (CB) imply that representations of objects in the focus of attention are stable and coherent. However, CB occurs for objects in the focus of attention. Here, we explore this apparent contradiction and the possibility that changes can be detected without having a complete and stable representation of the prechange object. The first experiment required observers to recognize a prechange object and a postchange object after viewing arrays of various sizes in which the prechange object was replaced by the postchange object after a brief delay. Results indicated that the representation of the prechange object was strong enough to cue a change but not strong enough to support accurate recognition. The remaining experiments demonstrated that the representation of the prechange object is volatile in that a shift in the display or the presence of a postchange object can disrupt the representation. These findings add to current theories of attention and representations by showing that attention may result in volatile representations that can support change detection without supporting accurate recognition.