Publications of Brody, G.

Images of objects are interpreted as symbols: A case study of automatic size measurement

Are photographs of objects presented on a screen in an experimental context treated as the objects themselves or are they interpreted as symbols standing for objects? We addressed this question by investigating the size Stroop effect—the finding that people take longer to judge the relative size of two pictures when the real-world size of the depicted objects is incongruent with their display size. In Experiment 1, we replicated the size Stroop effect with new stimuli pairs (e.g., a zebra and a watermelon). In Experiment 2, we replaced the large objects in Experiment 1 with small toy objects that usually stand for them (e.g., a toy zebra), and found that the Stroop effect was driven by what the toys stood for, not by the toys themselves. In Experiment 3, we showed that the association between an image of a toy and the object the toy typically stands for is not automatic: when toys were pitted against the objects they typically represent (e.g., a toy zebra versus a zebra), images of toys were interpreted as representations of small objects, unlike in Experiment 2. We argue that participants interpret images as discourse-bound symbols and automatically compute what the images stand for in the discourse context of the experimental situation.

Twelve-month-olds disambiguate new words using mutual-exclusivity inferences

Representing objects in terms of their kinds enables inferences based on the long-term knowledge made available through kind concepts. For example, children readily use lexical knowledge linked to familiar kind concepts to disambiguate new words (e.g., “find the toma”): they exclude members of familiar kinds falling under familiar kind labels (e.g., a ball) as potential referents and link new labels to available unfamiliar objects (e.g., a funnel), a phenomenon dubbed as ‘mutual exclusivity’. Younger infants’ failure in mutual exclusivity tasks has been commonly interpreted as a limitation of early word-learning or inferential abilities. Here, we investigated an alternative explanation, according to which infants do not spontaneously represent familiar objects under kind concepts, hence lacking access to the information necessary for rejecting them as referents of novel labels. Building on findings about conceptual development and communication, we hypothesized that nonverbal communication could prompt infants to set up kind-based representations which, in turn, would promote mutual exclusivity inferences. This hypothesis was tested in a looking-while-listening task involving novel word disambiguation. Twelve-month-olds saw pairs of objects, one familiar and one unfamiliar, and heard familiar kind labels or novel words. Across two experiments providing a cross-lab replication in two different languages, infants successfully disambiguated novel words when the familiar object had been pointed at before labeling, but not when it had been highlighted in a non-communicative manner (Experiment 1) or not highlighted at all (Experiment 2). Nonverbal communication induced infants to recruit kind-based representations of familiar objects that they failed to recruit in its absence and that, once activated, supported mutual-exclusivity inferences. Developmental changes in children’s appreciation of communicative contexts may modulate the expression of early inferential and word learning competences.