Abstract
The present experiment explored the effects of relatedness proportion (the proportion of semantically related word-prime/word-target trials) on behavioral and event-related potential (ERP) measures of semantic priming. Fourteen undergraduates participated in the lexical decision task under conditions of low and high proportion of related pairs with an SOA of 1000ms. The results showed that behavioral (shorter reaction times for related than for unrelated targets) and ERP (the larger N 400 for unrelated than for related targets) semantic priming effects were greater when the relatedness proportion was high compared to when it was low. In addition, time course and scalp distribution of N 400 were different according to the relatedness proportion. These results suggests that different temporal and spatial patterns of neural activities contribute word recognition processes in high and low proportion conditions.
