The time course of plausibility effects on eye movements in reading: evidence from noun-noun compounds.

Readers' eye movements were monitored as they read sentences containing noun-noun compounds that varied in frequency (e.g., elevator mechanic, mountain lion). The left constituent of the compound was either plausible or implausible as a head noun at the point at which it appeared, whereas the compound as a whole was always plausible. When the head noun analysis of the left constituent was implausible, reading times on this word were inflated, beginning with the first fixation. This finding is consistent with previous demonstrations of very rapid effects of plausibility on eye movements. Compound frequency did not modulate the plausibility effect, and all disruption was resolved by the time readers' eyes moved to the next word. These findings suggest (contra Kennison, 2005) that the parser initially analyzes a singular noun as a head instead of a modifier. In addition, the findings confirm that the very rapid effect of plausibility on eye movements is not due to strategic factors, because in the present experiment, unlike in previous demonstrations, this effect appeared in sentences that were globally plausible.

Semantic evaluation of syntactic structure: evidence from eye movements.

An eye movement study of temporarily ambiguous closure sentences confirmed that the early closure penalty in a sentence like While John hunted the frightened deer escaped is larger for a simple past verb (hunted) than for a past progressive verb (was hunting). The results can be explained by the observation that simple past tense verbs convey an external viewpoint on an event, which presumably fits best when the event described has an endpoint. A definite description object supplies an endpoint. Consequently, to give up the late closure analysis of the post-verbal object when the verb is in the simple past tense, the processor is abandoning an analysis with semantically-expected properties for one which is not as good semantically. By contrast, a progressive verb denotes an activity which does not require an endpoint and therefore is neutral with respect to whether or not it takes an object.