Event-related brain potential evidence for early effects of neighborhood density in word recognition

Orthographic neighborhood density (ND) has been shown to play an important role in lexical access. In this study, event-related potentials were recorded as participants read sentences terminating in a high or low ND word, which was either congruent or incongruent with the sentence context. High ND words elicited a significantly more positive-going waveform at 150-300 ms post-stimulus onset than low ND words, whereas items seen in incongruent sentence contexts resulted in a larger N400 amplitude than those seen in congruent sentence contexts. We suggest that high ND items result in greater initial global activation in the lexical system, reflected in the early positivity, and that this activation proceeds automatically and independently of context.