The time course of picture-word interference

If a word is printed inside the outline drawing of a concrete object, interference patterns as in Stroop research are obtained under the instruction to name the picture or to read the word. Smith and Magee (1980) have shown that these patterns change fundamentally if the naming or reading task is replaced by a categorizing task. Their results seem to corroborate the relative speed hypothesis, which explains Stroop-like interferences by faster processing of the distractor than the target. Two experiments are reported here in which the time course of picture-word interferences was analyzed by a systematically varied stimulus onset asynchrony (SOA) of the two stimulus components in the picture-naming, word-reading, picture-categorizing, and word-categorizing tasks. The results argue against the relative speed hypothesis and suggest a functional internal processing asymmetry between inhibition-immune recoding, effective in word reading and picture categorizing, and inhibition-susceptible recoding in picture naming and word categorizing.