Abstract
Two contrasting accounts for priming in visual search have been proposed. The main difference between the two is the level of perceptual processing at which the priming effects are assumed to occur, whether priming is assumed to operate through the selective facilitation of features or at the level of selection of objects for response. The aim with the experiments here was to contrast these accounts. In the first two experiments observers performed a search for the odd diamond among two distractor diamonds. Each diamond had two colors but the configuration of colors within the diamonds was different for the two experiments, configurations previously shown to lend themselves differently well to object formation. The results show that priming can be both feature- and object-based depending on the topological properties of the stimuli in each case. This was confirmed in a third study where a quite dissimilar stimulus set was used to address the same question yielding similar results as before. Priming is thus shown to operate at various levels of perceptual processing, a result consistent with new findings from neuroimaging and neuropsychology.