How Does Speaking A Free Word Order Language Influence Sentence Planning and Production? Evidence From Pitjantjatjara (Pama-Nyungan, Australia).

Sentence production is a stage-like process of mapping a conceptual representation to the linear speech signal via grammatical rules. While the typological diversity of languages is vast and thus must necessarily influence sentence production, psycholinguistic studies of diverse languages are comparatively rare. Here, we present data from a sentence planning and production study in Pitjantjatjara, an Australian Indigenous language that has highly flexible word order. Forty-nine (N = 49) native speakers described pictures of two-participant scenes while their eye-movements were recorded. Participants produced all possible orders of agent, patient, and verb. There was a general preference to produce agent-initial orders, but word order was influenced by the semantic properties of agent and patient referents (± human). Analyses of participants' eye-movements revealed early relational encoding of the entire event, whereby speakers distributed their attention between agent and patient referents in a manner that is different than typically observed in languages that have more restricted word order options. Relational encoding was influenced by the word order that participants eventually produced. The results provide evidence to suggest that sentence planning in Pitjantjatjara is a hierarchical process, in which early relational encoding creates a wholistic conceptualization of an event, possibly driven by pressure to decide upon one of many possible word orders.