The effect of familiarity on visual-search performance: evidence for learned basic features.

In this study, the effects of familiarity on visual search were investigated. To avoid any confounding between familiarity and visual-feature differences between item pairs, Ns and mirror-Ns were presented as target and as distractors to a group of German participants and to a group of Slavic participants. For the Germans only N was familiar, whereas for the Slavs both N and mirror-N were familiar. The results show that search was difficult only when the Germans had to find an N among mirror-Ns. In any other case, search was efficient. Therefore, our results demonstrate that, contrary to earlier suggestions, search for a familiar item among familiar distractors can be easy. This supports the hypothesis that familiarity improves distractor grouping. However, the data are also compatible with the idea that letters are standard or basic features, which implies that basic features can be learned.