Phonological priming and auditory event-related brain potentials

Phonological priming effects on auditory event-related brain potentials were compared across different numbers of syllables shared between target words and preceding prime words or pseudowords. All items of words and pseudowords consisted of 3 syllables, and the subject's task was to make a judgment whether the item belonged to a designated category. A large negative wave (N400),commencing at about 250 ms poststimulus and lasting for about 700 ms, was observed irrespective of primes and targets. When targets were preceded by word-primes that shared the first one or two syllables, the onset of N400 at the Frontal site was earlier and the initial negative-going phase was steeper than in other conditions. In contrast, the magnitude of N400 to targets was reduced, when the primes were pseudowords that shared the first two syllables. These two types of early and later phonological priming effects were interpreted to reflect facilitations during spoken word recognition at the pre-lexical (phonological) and post-lexical (semantic or contextual integrations levels, respectively.