Priming of early closure: evidence for the lexical boost during sentence comprehension

Two self-paced reading experiments investigated priming in sentences containing 'early' vs. 'late closure' ambiguities. Early closure sentences impose relatively large processing costs at the point of syntactic disambiguation. The current study investigated a possible way to reduce processing costs. Target sentences were temporarily ambiguous and were disambiguated towards either the preferred 'late' closure analysis or the dispreferred 'early' closure analysis. Each target sentence was preceded by a prime that was either structurally identical or that required a different syntactic analysis. In Experiment 1, all the prime sentences shared the same critical verb as the target. In Experiment 2, verb repetition was eliminated by reorganising the stimuli from Experiment 1. In Experiment 1, processing of the disambiguating verb was facilitated when an 'early' closure target sentence followed an 'early' closure prime. In Experiment 2, there were no significant priming effects, although an overall difference in processing time favoured 'late closure' targets. Combined analyses verified that the pattern of results in Experiment 1 differed significantly from Experiment 2. These experiments provide the first indication that 'early' closure analyses can be primed and that such priming is more robust when a critical verb appears in both the prime and the target sentence. The results add to the body of data indicating a 'lexical boost' for syntactic priming effects during comprehension. They have implications for theories of syntactic representation and processing.