Word-based grouping affects the prime-task effect on semantic priming

Semantic priming between words is reduced or eliminated if a low-level task such as letter search is performed on the prime word (the prime task effec t), a finding used to question the automaticity of semantic processing of w ords. This idea is critically examined in 3 experiments with a new design t hat allows the search target to occur both inside and outside the prime wor d. The new design produces the prime task effect (Experiment 1) but shows s emantic negative priming when the target letter occurs outside the prime wo rd (Experiments 2 and 3). It is proposed that semantic activation and primi ng are dissociable and that inhibition and word-based grouping are responsi ble for reduction of semantic priming in the prime task effect.