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Abstract Young children tend to generalize novel names for novel solid objects by similarity in shape, a phenomenon dubbed 'the shape bias'. We believe that the critical insights needed to explain the shape bias in particular, and cognitive development more generally, come from Dynamic Systems Theory. We present two examples of recent work focusing on the real‐time decision processes that underlie performance in the tasks used to measure the shape bias. We show how this work, and the dynamic systems perspective, sheds light on the controversy over the origins and development of the shape bias. In addition, we suggest that this dynamic systems perspective provides the right level for explanations of development because it requires a focus on the details of behavior over multiple timescales.

Abstract Two experiments explore children's spontaneous labeling of novel objects as a method to study early lexical access. The experiments also provide new evidence on children's attention to object shape when labeling objects. In Experiment 1, the spontaneous productions of 21 23‐ to 28‐month‐olds (mean 26;28) shown a set of novel, unnamed objects were analyzed both in terms of the specific words said and, via adult judgments, their likely perceptual basis. We found that children's spontaneous names were cued by the perceptual feature of shape. Experiment 2 examines the relation between spontaneous productions, name generalizations in a structured task, and vocabulary development in a group of children between 17 and 24 months of age (mean 21;6). Results indicate that object shape plays an important role in both spontaneous productions and novel noun generalization, but contrary to current hypotheses, children may name objects by shape from the earliest points of productive vocabulary development and this tendency may not be lexically specific.

AbstractConnectionist and dynamic systems approaches to development are similar in that they are both emergentist theories that take a very different perspective from more traditional symbolic systems. Moreover, they are both based on similar mathematical principles. Nevertheless, connectionism and dynamic systems differ in the approach they take to the study of development. We argue that differences between connectionist and dynamic systems approaches in terms of the basic components of the models, what they see as the object of study, how they view the nature of knowledge and their notions of developmental change mean that they each stand to make different and unique contributions to a more complete theory of development. We present an example from our work on how children learn to learn words that illustrates the complementary nature of connectionist and dynamic systems theories.

AbstractWe examine developmental interactions between context, exploration, and word learning. Infants show an understanding of how nonsolid substances are categorized that does not reliably transfer to learning how these categories are named in laboratory tasks. We argue that what infants learn about naming nonsolid substances is contextually bound – most nonsolids that toddlers are familiar with are foods and thus, typically experienced when sitting in a highchair. We asked whether 16‐month‐old children's naming of nonsolids would improve if they were tested in that typical context. Children tested in the highchair demonstrated better understanding of how nonsolids are named. Furthermore, context‐based differences in exploration drove differences in the properties attended to in real‐time. We discuss what implications this context‐dependency has for understanding the development of an ontological distinction between solids and nonsolids. Together, these results demonstrate a developmental cascade between context, exploration, and word learning.

AbstractChildren with delays in expressive language (late talkers) have heterogeneous developmental trajectories. Some are late bloomers who eventually "catch‐up," but others have persisting delays or are later diagnosed with developmental language disorder (DLD). Early in development it is unclear which children will belong to which group. We compare the toddler vocabulary composition of late talkers with different long‐term outcomes. The literature suggests most children with typical development (TD) have vocabularies dominated by names for categories organized by similarity in shape (e.g., cup), which supports a bias to attend to shape when generalizing names of novel nouns—a bias associated with accelerated vocabulary development. Previous work has shown that as a group, late talkers tend to say fewer names for categories organized by shape and are less likely to show a "shape bias" than TD children. Here, in a retrospective analysis of 850 children, we compared the vocabulary composition of groups of toddlers who were late bloomers or persisting late talkers. At Time 1 (13‐27 months), the persisting late talkers said a smaller proportion of shape‐based nouns than both TD children and late bloomers who "caught up" to typically sized vocabularies months later (18‐38‐months). Additionally, children who received a DLD diagnosis between 4 and 7 years said a significantly smaller proportion of shape‐based nouns in year two than TD children and children with other diagnoses (e.g., dyslexia). These findings bring new insight into sources of heterogeneity amongst late talkers and offer a new metric for assessing risk.Research Highlights
Toddler vocabulary composition, including the proportion of names for categories organized by shape, like spoon, was used to retrospectively compare outcomes of late talking children
Persisting Late Talkers said a smaller proportion of shape‐based nouns during toddlerhood relative to Late Bloomers (late talkers who later caught up to have typically‐sized vocabularies)
Children with later DLD diagnoses said a smaller proportion of shape‐based nouns during toddlerhood relative to children without a DLD diagnosis
The data illustrate the cascading effects of vocabulary composition on subsequent language development and suggest vocabulary composition may be one important marker of persisting delays

AbstractWords direct visual attention in infants, children, and adults, presumably by activating representations of referents that then direct attention to matching stimuli in the visual scene. Novel, unknown, words have also been shown to direct attention, likely via the activation of more general representations of naming events. To examine the critical issue of how novel words and visual attention interact to support word learning we coded frame‐by‐frame the gaze of 17‐ to 31‐month‐old children (n = 66, 38 females) while generalizing novel nouns. We replicate prior findings of more attention to shape when generalizing novel nouns, and a relation to vocabulary development. However, we also find that following a naming event, children who produce fewer nouns take longer to look at the objects they eventually select and make more transitions between objects before making a generalization decision. Children who produce more nouns look to the objects they eventually select more quickly following the naming event and make fewer looking transitions. We discuss these findings in the context of prior proposals regarding children's few‐shot category learning, and a developmental cascade of multiple perceptual, cognitive, and word‐learning processes that may operate in cases of both typical development and language delay.Research Highlights
Examined how novel words guide visual attention by coding frame‐by‐frame where children look when asked to generalize novel names.
Gaze patterns differed with vocabulary size: children with smaller vocabularies attended to generalization targets more slowly and did more comparison than those with larger vocabularies.
Demonstrates a relationship between vocabulary size and attention to object properties during naming.
This work has implications for looking‐based tests of early cognition, and our understanding of children's few‐shot category learning.

Abstract Two experiments demonstrate that 14‐ to 18‐month‐old toddlers can adaptively change how they categorize a set of objects within a single session, and that this ability is related to vocabulary size. In both experiments, toddlers were presented with a sequential touching task with objects that could be categorized either according to some perceptually salient dimension corresponding to a taxonomic distinction (e.g. animals vs. vehicles) or to some less obvious dimension (e.g. rigid vs. deformable). In each experiment, children with larger productive vocabularies responded to both dimensions, showing evidence of sensitivity to each way of categorizing the items. Children with smaller productive vocabularies attended only to the taxonomically related categorical grouping. These experiments confirm that toddlers can adaptively shift the basis of their categorization and highlight the dynamic interaction between the child and the current task in early categorization.