The Sternberg Memory Scanning Task is one of the most influential paradigms in cognitive psychology. Participants memorise a small set of digits (set sizes 2, 4, and 6), then see a single probe digit and decide as quickly as possible whether it was in the set (F = yes) or not (J = no).

The task's signature finding is a linear increase in reaction time with set size of approximately 35–50 ms per additional item. Sternberg (1966) interpreted this as evidence for a serial exhaustive search: the probe is compared one by one to every item in the set, even after a match is found. This slope — the memory-scanning rate — is a sensitive index of working-memory processing speed.

The slope is comparable for positive probes (item in set) and negative probes (item not in set), which is the defining feature of serial exhaustive search (as opposed to self-terminating search, which would predict shallower positive slopes).

This implementation uses three set sizes (2, 4, 6) with equal numbers of positive and negative probes at each size. A variable blank retention interval between set offset and probe onset prevents participants from timing the probe onset and producing anticipatory responses. Practice trials with correct/incorrect feedback precede the main task.