PEBL Hub — IRB Fact Sheet — 2026-10-07
Sternberg Memory Scanning Task
Memory
Processing Speed
Category:Memory
Duration:~8 minutes
Parameters:9 configurable parameters available
Version:1.0
Description
A memory scanning task in which participants memorize a set of letters and then judge whether probe letters were in the memorized set.
Participants memorize a short set of letters (set sizes of 2, 4, and 6 by default). They are then shown a series of individual probe letters and must respond whether each probe was present or absent from the memorized set. Response time increases linearly with set size, providing a measure of memory scanning speed.
Measures: Memory scanning speed, short-term memory retrieval
Key Parameters
| length1 | Set size 1 (default: 2) |
| length2 | Set size 2 (default: 4) |
| length3 | Set size 3 (default: 6) |
| rounds | Number of rounds. Rounds repeat all set sizes in order. (default: 2) |
| samestim | Whether the same stimuli should be used in each round. (default: 1) |
| trialsperblock | Number of target and foil trials per block (total trials = 2x this). (default: 25) |
| isi | Inter-stimulus interval. Time in ms of blank screen after response and before next stimulus. (default: 50) |
| stimset | Characters to sample the stimulus set from. Must contain at least as many as largest set size. (default: BCDFGHJKLMNPQRSTVWZ) |
| responsemode | Response method: auto (platform-aware), keyboardShift (L/R shift), keyboardSafe (Z/slash for web), arrowLR (left/right arrows), mousetarget (click targets), mousebutton (L/R mouse buttons), userselect (custom keys), touchtarget (large touch targets) (default: auto) |
| responselabels | Semantic labels for left and right responses (default: Array) |
Example Data Output (5 sample rows)
| subNum | length | trial | set | stim | targetfoil | resp | corr | rt |
|---|---|---|---|---|---|---|---|---|
| 225 | 2 | 1 | RD | R | T | present | 1 | 804 |
| 225 | 2 | 2 | RD | Q | F | absent | 1 | 1728 |
| 225 | 2 | 3 | RD | D | T | present | 1 | 827 |
| 225 | 2 | 4 | RD | R | T | present | 1 | 627 |
| 225 | 2 | 5 | RD | D | T | present | 1 | 519 |
References
Sternberg, S. (1966). High-speed scanning in human memory. Science, 153(3736), 652-654.
Mueller, S. T. (2012). The PEBL Sternberg Scanning Task. Computer software retrieved from http://pebl.sf.net/battery.html