Syntactic constraints on structural priming in L2 development: Effects of lexical overlap within and across structures

We test whether structural priming is syntactically constrained in first language (L1) and second language (L2) speakers. In a written production task, 68 L1 English speakers and 144 L2 English learners described transfer-of-possession events shown in pictures by using double-object (DO) datives (‘The artist sells the sailor the knife’) or prepositional-object (PO) datives (‘The artist sells the knife to the sailor’). The preceding prime sentences were either DO or PO datives, syntactically related locatives (‘The boy carries the cake to the soldier’) or syntactically unrelated infinitivals (‘The monk brings the cake to share’). Additionally, verbs between prime and target sentences either overlapped or were different. L1 speakers showed structural priming of datives from datives and locatives, yet not from infinitivals. Higher-proficiency L2 learners showed priming only within datives; yet, lower-proficiency learners demonstrated dative priming from datives, locatives and infinitivals. Lexical overlap in verbs contributed to priming within datives, yet not from infinitivals to datives. The results show that structural priming in L1 speakers and in higher-proficiency L2 learners does not cross syntactic boundaries. In L2 development, lexical surface overlap (‘to’) between infinitivals and datives occasions across-structure priming. We discuss implications of such form-based across-structure priming in L2 development for learning and language change.