U.S. psychologists say they've determined an error in visual memory occurs immediately after people see an image.
Psychologists Helene Intraub and Christopher Dickinson of the University of Delaware were interested in a specific common type of false visual memory that occurs in people of all ages. Known as the "boundary extension," it occurs when people report the boundaries of an image stretched farther than the actual boundaries of the image they saw.
The psychologists were interested in determining how quickly that error occurs, that is, how long a scene needs to be interrupted before people become convinced they saw more than they actually did.
Under a number of conditions, the researchers showed volunteers the identical photograph twice. The two views were interrupted by a display of lines and curves that was as brief as 42 milliseconds.
The volunteers reported the second view appeared "closer up," and showed more of the background, even though the two views were actually of the same photograph. In other words, the researchers said, the memory error known as the boundary extension occurred immediately after viewing an image.
The study is detailed in the journal Psychological Science.
