A test for iconic sensory memory

Sperling’s participants viewed a grid of letters flashed on a screen for a split second, then attempted to recall as many of the letters as possible. In the whole report condition (a), they averaged approximately four items, usually from a single row. However, the partial report condition (b) indicated that participants could remember far more than four letters, as long as they were cued within 1–2 seconds before the memory faded. Participants could usually name any row of four items, depending on the row they were cued to recite.