[Activation of the semantic memory by subliminal word stimuli? An analysis using event-related potentials]

There is a hotly debated question as to whether the meaning of a word can be assessed in the lexicon before conscious identification of this word is possible. Some authors have reported shorter lexical decision times for words, which had been preceded by primes, that had been masked below threshold. This effect was taken as evidence for an automatic activation of the lexicon by the unidentified prime. We report an ERP study using the N400 potential and lexical decision time as an index for associative activation of the lexicon. In a condition with supra-threshold primes the typical acceleration of lexical decision time and reduction of N400 amplitude was found for semantically related target words. In the sub-threshold condition, however, no evidence was found for priming in RT and ERP data. This pilot data, as well as previous RT studies, question the findings gathered on sub-threshold priming. No dissociation between RT and ERP parameters was found in the present study.