Objects were chosen from a selection of 26 household items. These were coffee jar, duster, 3 1/4-inch computer disk, video cassette, fitness shoes, scissors, calculator, milk carton, measuring ruler, clock, book, gloves, keys, cup, saucer, compact disc, tin opener, wallet, light bulb, washing up bottle, soft-drink can, bottle top, can opener, envelope, cheque book, and an instant mashed-potato sachet. Pairs of images were taken with a digital camera with one object being removed for one of the pairs. Each object could appear twice in the same display. This was to ensure that no one item was unique. Display attributes used in Experiments 1-3 were replicated as closely as possible (e.g., the same number of objects in each display, although some real-world objects were smaller). The display background was also different (white as opposed to light purple). As with Experiments 2 and 3, object attributes (e.g., color and location) for each trial were presented pseudo-randomly with the exception that for every onset trial the same pair of images would be repeated to create an offset trial by reversing the presentation order of the two frames. Again, this crucial control ensured that any difference in the detection rates of each pair could be due only to the onset or offset of an object with all other potentially confounding factors being controlled.