N400 solution effect of Chinese character fragments: an orthographic neighborhood size effect.

In this study, event-related brain potentials (ERPs) elicited by fragments of Chinese single-character words were simultaneously recorded while participants completed a delayed character-matching task as fast as possible, wherein probe characters were matched with their prior fragments. The number of solutions for such fragments was manipulated. Results indicate that fragments completed with several characters elicited greater N400 than did fragments with a single solution. Behavioral results demonstrated that "multiple-solution" responses were slower and had lower accuracy rates than the "one-solution" responses. In this article, both behavioral and N400 solution-effects are interpreted to provide evidence that supports the interactive activation model (IAM) but counters the efficacy of serial search models.