Children's knowledge of superordinate words predicts subsequent inductive reasoning.

Children's early language knowledge-typically assessed using standardized word comprehension tests or through parental reports-has been positively linked to a variety of later outcomes, from reasoning tests to academic performance to income and health. To better understand the mechanisms behind these links, we examined whether knowledge of certain "seed words"-words with high inductive potential-is positively associated with inductive reasoning. This hypothesis stems from prior work on the effects of language on categorization suggesting that certain words may be important for helping people to deploy categorical hypotheses. Using a longitudinal design, we assessed 36 2- to 4-year-old children's knowledge of 333 words of varying levels of generality (e.g., toy vs. pinwheel, number vs. five). We predicted that adjusting for overall vocabulary, knowledge of more general words (e.g., toy, number) would predict children's performance on inductive reasoning tasks administered 6 months later (i.e., a subset of the Stanford-Binet Intelligence Scales for Early Childhood-Fifth Edition [SB-5] and Woodcock-Johnson Tests of Cognitive Abilities [WJ] concept formation tasks). This prediction was confirmed for one of the measures of inductive reasoning (i.e., the SB-5 but not the WJ) and notably for the task considered to be less reliant on language. Although our experimental design demonstrates only a correlational relationship between seed word knowledge and inductive reasoning ability, our results are consistent with the possibility that early knowledge of certain seed words facilitates performance on putatively nonverbal reasoning tasks.

Effects of past language experience and present language context on the shape bias in Spanish-English bilingual children.

English-monolingual children develop a shape bias early in language acquisition, such that they more often generalize a novel label based on shape than other features. Spanish-monolingual children, however, do not show this bias to the same extent (Hahn & Cantrell, 2012). Studying children who are simultaneously learning both Spanish and English presents a unique opportunity to further investigate how this word-learning bias develops. Thus, we asked how Spanish-English bilingual children (Mage  = 21.31 months) perform in a novel-noun generalization (NNG) task, specifically examining how past language experience (i.e. language exposure and vocabulary size) and present language context (i.e. whether the NNG task was conducted in Spanish or English) influence the strength of the shape bias. Participants completed the NNG task either entirely in English (N = 16) or entirely in Spanish (N = 16), as well as language understanding tasks in both English and Spanish to ensure that they understood what the experimenter was asking them to do. Parents completed a language exposure survey and vocabulary checklists in Spanish and English. There was a significant interaction between condition and choice type: Bilingual children in the English condition showed a shape bias in the NNG task, but bilingual children in the Spanish condition showed no reliable biases. No measures of past language experience were related to NNG task performance. These results suggest that when learning new words, bilingual children are attuned to the regularities of the present language context, and prior language experiences may play a more secondary role.

When Time Shifts the Boundaries: Isolating the Role of Forgetting in Children's Changing Category Representations.

In studies of children's categorization, researchers have typically studied how encoding characteristics of exemplars contribute to children's generalization. However, it is unclear whether children's internal cognitive processes alone, independent of new information, may also influence their generalization. Thus, we examined the role that one cognitive process, forgetting, plays in shaping children's category representations by conducting three experiments. In the first two experiments, participants (NExp1=37, Mage=4.02 years; NExp2=32, Mage=4.48 years) saw a novel object labeled by the experimenter and then saw five new objects with between one and five features changed from the learned exemplar. The experimenter asked whether each object was a member of the same category as the exemplar; children saw the five new objects either immediately or after a five-minute delay. Children endorsed category membership at higher rates at immediate test than at delayed test, suggesting that children's category representations became narrower over time. In Experiment 3, we investigated forgetting as a key mechanism underlying the narrowing found in Experiments 1 and 2. We showed participants (NExp3=34, Mage=4.20 years) the same exemplars used in Experiments 1 and 2; then, either immediately or after a five-minute delay, we showed children seven individual object features and asked if each one had been part of the exemplar. Children's accuracy was lower after the delay, showing that they did indeed forget individual features. Taken together, these results show that forgetting plays an important role in changing children's newly-learned categories over time.

Does the public know what researchers know? Perceived task difficulty impacts adults' intuitions about children's early word learning.

The present study examined adults' understanding of children's early word learning. Undergraduates, non-parents, parents, and Speech-Language Pathologists (N = 535, 74% female, 56% White) completed a survey with 11 word learning principles from the perspective of a preschooler. Questions tested key principles from early word learning research. For each question, participants were prompted to select an answer based on the perspective of a preschooler. Adults demonstrated aligned intuitions for all principles except those derived from domain-general theories, regardless of experience with language development (Experiment 1). Experiment 2 revealed that perceived difficulty of a task for a preschooler impacted adults' reasoning about word learning processes. Experiment 3 ruled out level of confidence and interest as mechanisms to explain the results. These results highlight disconnects in knowledge between the cognitive development research community and the general public. Therefore, efforts must be made to communicate scientific findings to the broader non-academic community, emphasizing children's ability to excel at word learning in the face of task difficulty.

The role of syntactic cues in monolingual and bilingual two-year-olds' novel word disambiguation.

Although linguistic and nonlinguistic cues help young children infer meaning when presented with unfamiliar words, little is known about how syntactic information and early bilingual experience shape word learning. This study examined how monolingual and bilingual 24- to 30-month-olds' disambiguation of novel words during a mutual exclusivity task differs as a function of syntactic cues, age, and productive vocabulary. English monolinguals and Spanish-English bilinguals were presented with familiar and novel objects within a syntactic context (e.g., "Give me the blick!") or in isolation (e.g., "Blick!"). Results showed that monolinguals and bilinguals adhered to mutual exclusivity more often when provided with syntactic cues than when those cues were absent. Furthermore, bilinguals' mutually exclusive disambiguation of novel words increased with age, but only when syntactic cues were available. These results provide insight into factors that influence children's disambiguation of novel words. The theoretical implications of these findings are discussed.

Lexical access speed and the development of phonological recoding during immediate serial recall.

A recent Registered Replication Report (RRR) of the development of verbal rehearsal during serial recall (Elliott et al., 2021) revealed that children verbalized at younger ages than previously thought (Flavell et al., 1966), but did not identify sources of individual differences. Here we use mediation analysis to reanalyze data from the 934 children ranging from 5 to 10 years old from the RRR for that purpose. From ages 5 to 7, the time taken for a child to label pictures (i.e. isolated naming speed) predicted the child's spontaneous use of labels during a visually-presented serial reconstruction task, despite no need for spoken responses. For 6- and 7-year-olds, isolated naming speed also predicted recall. The degree to which verbalization mediated the relation between isolated naming speed and recall changed across development. All relations dissipated by age 10. The same general pattern was observed in an exploratory analysis of delayed recall for which greater demands are placed on rehearsal for item maintenance. Overall, our findings suggest that spontaneous phonological recoding during a standard short-term memory task emerges around age 5, increases in efficiency during the early elementary school years, and is sufficiently automatic by age 10 to support immediate serial recall in most children. Moreover, the findings highlight the need to distinguish between phonological recoding and rehearsal in developmental studies of short-term memory.

The roles of item repetition and position in infants' abstract rule learning.

We asked whether 11- and 14- month-old infants' abstract rule learning, an early form of analogical reasoning, is susceptible to processing constraints imposed by limits in attention and memory for sequence position. We examined 11- and 14- month-old infants' learning and generalization of abstract repetition rules ("repetition anywhere," Experiment 1 or "medial repetition," Experiment 2) and ordering of specific items (edge positions, Experiment 3) in 4-item sequences. Infants were habituated to sequences containing repetition- and/or position-based structure and then tested with "familiar" vs. "novel" (random) sequences composed of new items. Eleven-month-olds (N = 40) failed to learn abstract repetition rules, but 14-month-olds (N = 40) learned rules under both conditions. In Experiment 3, 11-month-olds (N = 20) learned item edge positions in sequences identical to those in Experiment 2. We conclude that infant sequence learning is constrained by item position in similar ways as in adults.

Two-year-olds' executive functioning: The influence of task-specific vocabulary knowledge.

Although many executive function (EF) tasks require only nonverbal responses, the language used by experimenters to explain the task may be important for young children's EF task performance. This study investigated how the vocabulary used in explaining an EF task affects 2-year-olds' performance. Experiment 1 used the standard instructions for the Reverse Categorization Task, in which children are asked to sort different-sized blocks into different-sized buckets according to one rule and then switch to a new rule. In Experiment 2, the task remained the same, but different instructions requiring less knowledge of size words were used. Children's productive vocabulary was assessed in both experiments but was only correlated with task performance in Experiment 1. These results suggest that task-specific vocabulary knowledge may play a role in children's performance on tasks designed to measure nonverbal cognitive ability.

Does bilingual experience affect early visual perceptual development?

Visual attention and perception develop rapidly during the first few months after birth, and these behaviors are critical components in the development of language and cognitive abilities. Here we ask how early bilingual experiences might lead to differences in visual attention and perception. Experiments 1-3 investigated the looking behavior of monolingual and bilingual infants when presented with social (Experiment 1), mixed (Experiment 2), or non-social (Experiment 3) stimuli. In each of these experiments, infants' dwell times (DT) and number of fixations to areas of interest (AOIs) were analyzed, giving a sense of where the infants looked. To examine how the infants looked at the stimuli in a more global sense, Experiment 4 combined and analyzed the saccade data collected in Experiments 1-3. There were no significant differences between monolingual and bilingual infants' DTs, AOI fixations, or saccade characteristics (specifically, frequency, and amplitude) in any of the experiments. These results suggest that monolingual and bilingual infants process their visual environments similarly, supporting the idea that the substantial cognitive differences between monolinguals and bilinguals in early childhood are more related to active vocabulary production than perception of the environment.