How message similarity shapes the timecourse of sentence formulation

Transforming a preverbal message into an utterance (e.g., The swimmer is pushing the paparazzo) requires conceptual and linguistic encoding. Two experiments tested whether the timecourse of sentence formulation is shaped jointly or independently by message-level and sentence-level processes. Eye-tracked speakers described pictures of simple events with verb-medial (SVO/OVS) and verb-initial (VSO/aux-OVS) sentences in Dutch. To assess effects of message-level and sentence-level variables on formulation, the experiments manipulated the ease of relational encoding at both levels: target events were preceded by conceptually similar or dissimilar prime events (event primes) that increased speakers’ familiarity with the action shown in the target event (e.g., pushing), and the prime events were accompanied by recorded active or passive descriptions (structural primes) that facilitated generation of suitable linguistic structures on target trials. The results showed effects of both types of primes on the form of target descriptions and on formulation. Speakers repeated the primed structures more often when target events were conceptually similar to the prime events. Importantly, conceptual similarity constrained the effects of structural primes on the timecourse of formulation: speakers showed more consistent deployment of attention to the two characters during linguistic encoding in structurally primed than unprimed active sentences, but conceptual familiarity reduced the priming effects in eye movements. Thus familiarity with message-level information can change how speakers express their messages and, during formulation, can provide conceptual guidance that supersedes effects of sentence-level variables. Effects of the event primes were stronger in VSO sentences, where early verb placement explicitly required early encoding of relational information, suggesting that linear word order can also constrain message-level influences on formulation.