The locus and nature of semantic congruity in symbolic comparison: evidence from the Stroop effect.

Pictures of animals with names of animals printed within the pictures were presented for comparative judgments of size based on either the pictures or the names. The picture-word compounds were compared faster with picture than with word as the relevant dimension. The comparisons of pictures were free of interference from the irrelevant names, but the comparisons of names suffered considerable Stroop interference from the irrelevant pictures. Large effects of semantic congruity characterized the comparisons of both pictures and words. Stroop congruity and semantic congruity did not interact even for comparison of words in which both were present, leading instead to additive effects. The results support theories that (1) place semantic congruity in the decision stage and (2) minimize the role of semantic processing as the basis of the semantic congruity effect.