Neon Brooks

Pragmatic Inference, Not Semantic Competence, Guides 3-Year-Olds' Interpretation of Unknown Number Words

Before children learn the specific meanings of numerals like six, do they know that they represent precise quantities? Previous studies have reported conflicting evidence and have found that children expect numerals to label precise quantities in some tasks but not in others (Condry & Spelke, 2008; Sarnecka & Gelman, 2004). In this article, we present evidence that some of childrens apparent successes are best explained not by domain-specific semantic understanding of number but instead by language-general pragmatic abilities. In Experiment 1, we replicated the findings of the previous studies in a within-subject design. When 3-year-olds saw a set labeled with a number (e.g., five) and an item was added, they preferred a new label (six) over the old one, as though they believed that number words have precise meanings. However, when 1 of 2 sets was labeled (e.g., as five) and children were asked to find the same quantity (five) or a new quantity (six), they performed identically whether the original set was changed in quantity or merely rearranged. Thus, when 2 numerals were offered as alternative labels for 1 set, children behaved as though they had precise meanings, whereas when they were asked to determine which of 2 sets a single numeral referred to, they did not. In Experiment 2, children were tested using similar methods but with novel nouns and objects that were transformed, instead of sets. Children showed the identical pattern of results despite lacking meanings for these words, suggesting that their judgments for numerals may not have relied on semantic knowledge that numerals have precise meanings. We propose that childrens behavior can be explained by the use of domain-general pragmatic inference and does not require positing domain-specific numerical knowledge.

Acquiring the meaning of free relative clauses and plural definite descriptions

Plural definite descriptions (e.g. the things on the plate) and free relative clauses (e.g. what is on the plate) have been argued to share the same semantic properties, despite their syntactic differences. Specifically, both have been argued to be nonquantificational expressions referring to the maximal element of a given set (e.g. the set of things on the contextually salient plate). We provide experimental support for this semantic analysis with the first reported simultaneous investigation of children’s interpretation of both constructions, highlighting how experimental methods can inform semantic theory. A Truth-Value Judgment task and an Act-Out task show that children know that the two constructions differ from quantificational nominals (e.g. all the things on the plate) very early on (4 years old). Children also acquire the adult interpretation of both constructions at the same time, around 6‐7 years old. This happens despite major differences in the frequency of these constructions, according to our corpus study of children’s linguistic input. We discuss possible causes for this late emergence. We also argue that our experimental findings contribute to the recent theoretical debate on the correct semantic analysis of free relatives.

Better together: Simultaneous presentation of speech and gesture in math instruction supports generalization and retention

When teachers gesture during instruction, children retain and generalize what they are taught (Goldin-Meadow, 2014). But why does gesture have such a powerful effect on learning? Previous research shows that children learn most from a math lesson when teachers present one problem-solving strategy in speech while simultaneously presenting a different, but complementary, strategy in gesture (Singer & Goldin-Meadow, 2005). One possibility is that gesture is powerful in this context because it presents information simultaneously with speech. Alternatively, gesture may be effective simply because it involves the body, in which case the timing of information presented in speech and gesture may be less important for learning. Here we find evidence for the importance of simultaneity: 3rd grade children retain and generalize what they learn from a math lesson better when given instruction containing simultaneous speech and gesture than when given instruction containing sequential speech and gesture. Interpreting these results in the context of theories of multimodal learning, we find that gesture capitalizes on its synchrony with speech to promote learning that lasts and can be generalized.

The Role of Gesture in Supporting Mental Representations: The Case of Mental Abacus Arithmetic

People frequently gesture when problem-solving, particularly on tasks that require spatial transformation. Gesture often facilitates task performance by interacting with internal mental representations, but how this process works is not well understood. We investigated this question by exploring the case of mental abacus (MA), a technique in which users not only imagine moving beads on an abacus to compute sums, but also produce movements in gestures that accompany the calculations. Because the content of MA is transparent and readily manipulated, the task offers a unique window onto how gestures interface with mental representations. We find that the size and number of MA gestures reflect the length and difficulty of math problems. Also, by selectively interfering with aspects of gesture, we find that participants perform significantly worse on MA under motor interference, but that perceptual feedback is not critical for success on the task. We conclude that premotor processes involved in the planning of gestures are critical to mental representation in MA.