Find the target shape in the grid as fast as possible. Feature searches pop out instantly; conjunction searches require careful scanning. Based on Treisman & Gelade (1980) Feature Integration Theory.
Very Easy
16 items, feature search — target pops out by color or shape.
Easy
20 items, feature search — slightly larger grid.
Medium
25 items, conjunction search — target shares features with distractors.
Hard
36 items, conjunction search — dense grid requires serial scanning.
Expert
49 items, conjunction search — maximum density and trials.
Scientific Background
Based on: Visual Search & Feature Integration Theory (Treisman & Gelade, 1980; Wolfe, 1994) (Treisman et al., 1980)