How long does it take to find a cause? An online investigation of implicit causality in sentence production.

Some interpersonal verbs show an implicit causality bias in favour of their subject or their object. Such a bias is generally seen in offline continuation tasks where participants are required to finish a fragment containing the verb (e.g., Peter annoyed Jane because ...). The implicit causality bias has been ascribed to the subject's focusing on the initiator of the event denoted by the verb. According to this "focusing theory" the implicit cause has a higher level of activation, at least after the connective "because" has been read. Recently, the focusing theory has been criticized by researchers who used a probe recognition or reading-time methodology. However no clear alternative has been proposed to explain the offline continuation data. In this paper, we report three experiments using an online continuation task, which showed that subjects took more time to imagine an ending when the fragment to be completed contained an anaphor that was incongruent with the verbal bias (e.g., Peter annoyed Jane because she ...). This result suggests that the offline continuation data could reflect the cognitive effort associated with finding a predicate with an agent incongruent with the implicit causality bias of a verb. In the discussion, we suggest that this effort could be related to the number of constraints that an incongruent clause must satisfy to be consistent with the causal structure of the discourse.