We discuss the causative-inchoative alternation in Turkish Sign Language (Türk Isaret Dili -- TID), and the age of acquisition effects on multi-predicate, complex constructions that are observed in both causative and inchoative events. We present a picture-description task performed by 24 adult signers, half of which were exposed to TID from birth…

The ability to understand the mental states of other individuals is central to human social behavior, yet some theory of mind capacities are shared with other species. Comparisons of theory of mind skills across humans and other primates can provide a critical test of the cognitive prerequisites necessary for different theory of mind skills to…

Languages differ in how they encode causal events, placing greater or lesser emphasis on the agent or patient of the action. Little is known about how these preferences emerge and the relative influence of cognitive biases and language-specific input at different stages in development. In these studies, we investigated the emergence of sentence…

Syntactic bootstrapping facilitates children's initial learning of verb meanings based on syntactic information. A challenging case is the argument-drop languages, where the number of argument NPs is not a reliable cue for distinguishing between transitive and intransitive verbs. Despite this fact, the availability of syntactic bootstrapping in…

Across a diverse range of languages, children proceed through similar stages in their production of causal language: their initial verbs lack internal causal structure, followed by a period during which they produce causative overgeneralizations, indicating knowledge of a productive causative rule. We asked in this study whether a child not…