a, b, e Effect of target’s color contrast on visual search performance. a Gaze scanpath when the target has low contrast (i.e., similar to the distractors). b Scanpath when the target has high contrast (different from the distractors). e Number of fixations to find the target as a function of target’s color contrast (plot shows mean ± s.e.m., n = 44–65 trials/contrast-level). c, d, f Similar plots for orientation contrast (difference in orientation between target and distractors in degrees, Δθ; n = 42–63 trials/contrast-level). g Effect of set size. Number of fixations to find the target as the number of items in the display varied between 5, 10, and 15; and the target’s orientation contrast varied from low (Δθ = 7∘) to medium-high (Δθ = 15∘) to very high (Δθ = 75∘). Plot shows mean ± s.e.m. in number of fixations (n = 42–63 trials for each combination of set size and Δθ).