Fig. 1.

Illustration of experimental conditions. (a) Example of a retro-cue trial. A sample display containing one or more memory items (here, colored squares) is presented. After a blank delay period, a cue (here, an arrow) indicates one of the items in memory which is more likely to be probed. After a further blank delay, a probe (here, an empty square) is presented indicating one item that should be reported: in this example, a color wheel is presented simultaneously with the probe and participants click on the wheel to indicate the remembered color. (b) A neutral-cue trial. This control condition is identical to a retro-cue trial except an uninformative stimulus (here, an asterisk) is presented in place of the retro-cue. (c) A no-cue trial. In this control condition, no stimulus is presented during the memory period, i.e. the display remains blank between the sample display and probe. (d) A post-cue trial. In this control condition, the probe display is presented simultaneously with the retro-cue, indicating the same item. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.)