Wide-angle memories of close-up scenes: a demonstration of boundary extension.

Boundary extension refers to a tendency to remember seeing a greater expanse of a scene than was shown in a photograph. It is hypothesized that the view shown in the stimulus activates expectations about the scene's layout just outside the picture's borders. Following presentation, the viewer remembers having seen this expected information, and this yields boundary extension. We provide photographs and instructions for conducting two brief demonstrations of the phenomenon and provide materials for a related class experiment on the journal's World-Wide Web site. These demonstrations of boundary extension provide graphic illustrations of the role of schematic expectancies in the representation of scenes and help to illustrate the role of real-world knowledge in cognition.

Effects of perceiving and imagining scenes on memory for pictures.

Boundary extension is the tendency to remember having seen a greater expanse of a scene than was shown. Four experiments tested whether a picture must depict a partial view of a scene for the distortion to occur. The premise was that partial views activate a perceptual schema, a representation of the expected scene structure outside the view. Participants were 473 undergraduates. Experiments 1 and 2 tested recognition memory and recall of 16 outline-objects presented in outline-scenes versus presentation on blank backgrounds. Experiments 3 and 4 compared memory for outline-objects when scene context was or was not imagined. Boundary errors consistent with the perceptual schema hypothesis only occurred for partial views (perceived or imagined). Results suggest that scene perception and imagination activate the same schematic representation.