Accessing singular antecedents in conjoined phrases.

Two experiments examined processing of singular pronouns when the antecedent (e.g., Mary) was a noun phrase (NP) in a conjoined phrase (e.g., Mary and John). Whole-sentence reading times showed an increase in processing time associated with splitting the conjoined phrase to access a single NP antecedent. The increase in processing occurred both when the antecedent was in the subject position and when it was in a nonsubject position. The source of the disruption was further investigated using eyetracking methods. Summing over regions of the text, the magnitude of the processing cost incurred by having to split a conjoined NP was closely comparable when there was and when there was not a gender-appropriate distracting potential antecedent. When there was no such potential antecedent, the increase in processing time occurred immediately in the pronoun region when eye movements were measured. In contrast, when there was a second discourse entity that matched the gender and number of the pronoun (but was not a plausible antecedent for the pronoun), eyetracking measures suggested that the processing difficulty was delayed until additional information was read that forced the antecedent to be one of the conjoined NPs. The results are interpreted in terms of Sanford and Garrod's (1981) scenario-based model of text comprehension.