Inhibitory semantic priming of lexical decisions due to failure to retrieve weakly activated codes.

Semantic priming effects from newly learned vocabulary words are examined in a lexical decision task. At low levels of learning, those primes whose meanings are recognizable but not recallable can inhibit responses to well-known, scmantically related target words, whereas those whose meaning are recallable produce either no effect or facilitation, depending on instructions concerning how to use the prime information. These results are consistent with the notion that semantic priming effects are determined at least in part by the nature of the retrieval operations performed on the prime and target, over and above influences due to spreading activation and confirmed or violated expectations. Specifically, they indicate a need to include mechanisms other than violated expectations that can produce inhibition of retrieval. Candidate mechanisms are discussed.