The Role of Speaker Knowledge in Children's Pragmatic Inferences.

During communication, conversational partners should offer as much information as is required and relevant. For instance, the statement "Some Xs Y" is infelicitous if one knows that all Xs Y. Do children understand the link between speaker knowledge and utterance strength? In Experiment 1, 5-year-olds (N = 32) but not 4-year-olds (N = 32) reliably connected statements of different logical strength (e.g., "The girl colored all/some of the star") to observers who were fully or partially informed. Four-year-olds' performance improved when observer knowledge could be assessed more easily (Experiment 2a, N = 25) but remained the same in a nonlinguistic version of Experiment 1 that preserved the epistemic requirements of the original study (Experiment 2b, N = 26). These findings have implications for the development of early communicative abilities.

Learning words from speakers with false beliefs.

During communication, hearers try to infer the speaker's intentions to be able to understand what the speaker means. Nevertheless, whether (and how early) preschoolers track their interlocutors' mental states is still a matter of debate. Furthermore, there is disagreement about how children's ability to consult a speaker's belief in communicative contexts relates to their ability to track someone's belief in non-communicative contexts. Here, we study young children's ability to successfully acquire a word from a speaker with a false belief; we also assess the same children's success on a traditional false belief attribution task. We show that the ability to consult the epistemic state of a speaker during word learning develops between the ages of three and five. We also show that false belief understanding in word-learning contexts proceeds similarly to standard belief-attribution contexts when the tasks are equated. Our data offer evidence for the development of mind-reading abilities during language acquisition.

The use of prosody during syntactic processing in children and adolescents with autism spectrum disorders.

In this study, we employed an eye-gaze paradigm to explore whether children (ages 8-12) and adolescents (ages 12-18) with autism spectrum disorders (ASDs) are able to use prosodic cues to determine the syntactic structure of an utterance. Persons with ASD were compared to typically developing (TD) peers matched on age, IQ, gender, and receptive language abilities. The stimuli were syntactically ambiguous but had a prosodic break that indicated the appropriate interpretation (feel the frog … with the feather vs. feel … the frog with the feather). We found that all groups were equally sensitive to the initial prosodic cues that were presented. Children and teens with ASD used prosody to interpret the ambiguous phrase as rapidly and efficiently as their TD peers. However, when a different cue was presented in subsequent trials, the younger ASD group was more likely to respond in a manner consistent with the initial prosodic cue rather than the new one. Eye-tracking data indicated that both younger groups (ASD and TD) had trouble shifting their interpretation as the prosodic cue changed, but the younger TD group was able to overcome this interference and produce an action consistent with the prosodic cue.