PEBL Hub — IRB Fact Sheet — 2026-10-07
Pattern Comparison (Sequential)
Memory
Processing Speed
Perception
Category:Processing Speed
Duration:~8 minutes
Parameters:9 configurable parameters available
Version:1.0
Description
A sequential pattern comparison task where participants memorize a dot pattern and then judge whether a second pattern is the same or different.
A dot grid pattern is displayed briefly, then erased. After a delay, a second pattern appears and participants judge whether it is the same as or different from the first. Measures visual short-term memory and pattern discrimination.
Measures: Visual short-term memory, pattern comparison, processing speed
Key Parameters
| similarfoil | should foil be similar to target (default: 1) |
| foildiff | Number of changes between target and foil (default: 3) |
| size | size of the target/foil matrices (default: 4) |
| givefeedback | Whether to give feedback (default: 1) |
| condsize | Number of trials per condition (x12) (default: 10) |
| prestime | presentation time in ms (default: 1500) |
| delay | Delay before judgment (default: 3500) |
| responsemode | Response method (default: auto) |
| responselabels | Semantic labels for responses (default: Array) |
Example Data Output (5 sample rows)
| subnum | trial | samediff | mat1 | mat2 | abstime | rt | resp | corr |
|---|---|---|---|---|---|---|---|---|
| example | 1 | diff | 0110111110000100 | 0101111001010100 | 3415 | 669 | different | 1 |
| example | 2 | same | 1010101000010111 | 1010101000010111 | 9506 | 1316 | same | 1 |
| example | 3 | diff | 0011011011000011 | 1011110011100000 | 16234 | 989 | different | 1 |
| example | 4 | same | 0101101101010001 | 0101101101010001 | 22639 | 668 | same | 1 |
| example | 5 | diff | 0100110111011000 | 0111000011011001 | 28720 | 677 | different | 1 |
References
Perez, W. A., Masline, P. J., Ramsey, E. G., & Urban, K. E. (1987). Unified tri-services cognitive performance assessment battery: Review and methodology. DTIC/TR-87-007.
Mueller, S. T. (2011). The PEBL Pattern Comparison Task. Computer software retrieved from http://pebl.sf.net/battery.html