Plausibility and argument structure in sentence comprehension

In two experiments, we investigated how reading time was affected by the plausibility of the prepositional phrase in subject-verb-noun-phrase-prepositional-phrase sentences, and the status of the prepositional phrase as argument versus adjunct of the verb. Highly plausible prepositional phrases were read faster than less plausible ones, and argument prepositional phrases were read faster than adjuncts. These effects appeared both in a self-paced reading experiment and in an experiment that measured eye movements during normal reading. The effects of plausibility were substantially larger and longer lasting than the effects of argument status, but both appeared very early in the reading of the prepositional phrase. The implications of these effects for models of parsing and sentence interpretation are discussed.