Person:

Ziegler, Jayden

Clearly, structural priming is a valuable tool for probing linguistic representation. But we don't think that the existing results provide strong support for Branigan & Pickering's (B&P's) model, largely because the priming effects are more confusing and diverse than their theory would suggest. Fortunately, there are a number of other experimental tools available, and linguists are increasingly making use of them.

What are the semantic representations that underlie language production? We use structural priming to distinguish between two competing theories. Thematic roles define semantic structure in terms of atomic units that specify event participants and are ordered with respect to each other through a hierarchy of roles. Event structures instead instantiate semantic structure as embedded sub-predicates that impose an order on verbal arguments based on their relative positioning in these embeddings. Across two experiments, we found that priming for datives depended on the degree of overlap in event structures. Specifically, while all dative structures showed priming, due to common syntax, there was a boost for compositional datives priming other compositional datives. Here the two syntactic forms have distinct event structures. In contrast, there was no boost in priming for dative light verbs, where the two forms map onto a single event representation. On the thematic roles hypothesis, we would have expected a similar degree of priming for the two cases. Thus, our results support event structural approaches to semantic representation and not thematic roles.

Verbs that are similar in meaning tend to occur in the same syntactic structures. For example, give and hand, which denote transfer of possession, both appear in the prepositional-object construction: “The child gave / handed the ball to the dog.” We can call the child a “giver” in one case and a “hander” in the other, or we can refer to her more generally as the agent, or doer of the action. Similarly, the dog can be called the recipient, and the ball, the theme. These generalized notions of agent, recipient, and theme are known as thematic roles. An important theoretical question for linguists and psycholinguists is what the set of thematic roles is. Are there a small number of very broad roles, perhaps with each one mapping onto a single canonical syntactic position? Or are there many distinct roles, several mapping to the same syntactic position but conveying subtly different meanings? We investigate this question across eleven structural priming experiments on Amazon Mechanical Turk (total N=2,914), asking whether speakers treat the thematic roles recipient and destination (i.e., location or spatial goal) as interchangeable, suggesting the broad role of goal, or distinct, suggesting two separate roles. To do so, we look for priming between dative sentences (e.g., “The man gave the ball to the dog”), which have a recipient role (dog), and locative sentences (e.g., “The man loaded hay onto the wagon”), which instead have a destination role (wagon). Our pattern of findings confirms that thematic role mappings can be primed independent of syntactic structure, lexical content, and animacy. However, we find that this priming does not extend from destinations to recipients (or vice versa), providing evidence that these two roles are distinct.

Structural priming in comprehension seems to be more variable than in production. Sometimes it occurs without lexical overlap, sometimes it does not. This raises questions about the use of abstract syntactic structure and how it varies across tasks. We use a visual-world eye-tracking judgment task and observe two kinds of priming effects. First, participants were more likely to switch to looking at the target referent immediately after the word when the syntactic structure of the target matched that of the prime. Second, participants also looked more to referents that could take on the thematic role that was in sentence-final position in the prime sentence, and thus in discourse focus. Critically, neither effect depended upon lexical overlap. Our results suggest that structural priming in comprehension manifests itself differently depending on situational demands, reflecting the activation of different levels of representation under different pressures.