Not all subjects are agents: Transitivity and meaning in early language comprehension

Children use syntax to guide sentence comprehension and verb learning. We explored the nature of the meanings children infer from syntactic evidence by examining the types of event-roles they can link with the subjects and objects of transitive verbs. In two experiments, 23-month-olds heard a novel verb in a transitive sentence while viewing pairs of events in which one participant acted on another without producing a clear effect (Experiment 1) or one participant moved relative to another without contacting it (Experiment 2). In both cases, children looked longer at the event in which the subject referent played a more prominent role. These findings suggest that children map a highly abstract conceptual-semantic asymmetry onto the syntactic difference between subjects and objects.