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Purpose: This study examines online speech processing in typically developing and late-talking 2-year-old children, comparing both groups' word recognition, word prediction, and word learning. Method: English-acquiring U.S. children, from the “When to Worry” study of language and social–emotional development, were identified as typical talkers ( n = 67, M age = 27.0 months, SD = 1.4; Study 1) or late talkers ( n = 30, M age = 27.0 months, SD = 2.0; Study 2). Children completed an eye-tracking task assessing their ability to recognize both nouns and verbs, to use verbs to predict an upcoming noun's referent, and to use verbs to infer the meaning of novel nouns. Results: Both typical and late talkers recognized nouns and verbs and used familiar verbs to predict the referents of upcoming nouns, whether the noun was familiar (“You can eat the apple”) or novel (“You can eat the dax”). Late talkers were slower in using familiar nouns to orient to the target and were both slower and less accurate in using familiar verbs to identify the upcoming noun's referent. Notably, however, both groups learned and retained novel word meanings with similar success. Conclusions: Late talkers demonstrated slower lexical processing, especially for verbs. Yet, their success in using familiar verbs to learn novel nouns suggests that, as a group, their slower processing did not impair word learning in this task. This sets the foundation for future work investigating whether these measures predict later language outcomes and can differentiate late talkers with transient delays from those with language disorders.

Labeling promotes infants' object categorization even when labels are rare. By 2 years, infants engage in "semi-supervised learning" (SSL), integrating labeled and unlabeled exemplars to learn categories. However, everyday learning contexts pose substantial challenges for infants' SSL. Here, two studies (n = 74, 51% female, 62% non-Hispanic White, 18% multiracial, 8% Asian, 6% Black, M

Significance Encoding objects in memory and recalling them later is fundamental to human cognition and emerges in infancy. Here, using a new recognition memory paradigm, we show that the way an object is named, either as a unique individual or as a member of a category, is instrumental in 12-mo-old infants’ encoding of and memory for that object. When the same name is applied consistently to a set of objects, infants encode primarily their commonalities. In contrast, when a unique name is applied to each object, infants encode each object’s unique features. Thus, even as infants begin to produce their first words, a single naming event exerts powerful, nuanced effects on the fundamental cognitive processes of object representation and memory., A foundation of human cognition is the flexibility with which we can represent any object as either a unique individual (my dog Fred) or a member of an object category (dog, animal). This conceptual flexibility is supported by language; the way we name an object is instrumental to our construal of that object as an individual or a category member. Evidence from a new recognition memory task reveals that infants are sensitive to this principled link between naming and object representation by age 12 mo. During training, all infants (n = 77) viewed four distinct objects from the same object category, each introduced in conjunction with either the same novel noun (Consistent Name condition), a distinct novel noun for each object (Distinct Names condition), or the same sine-wave tone sequence (Consistent Tone condition). At test, infants saw each training object again, presented in silence along with a new object from the same category. Infants in the Consistent Name condition showed poor recognition memory at test, suggesting that consistently applied names focused them primarily on commonalities among the named objects at the expense of distinctions among them. Infants in the Distinct Names condition recognized three of the four objects, suggesting that applying distinct names enhanced infants’ encoding of the distinctions among the objects. Infants in the control Consistent Tone condition recognized only the object they had most recently seen. Thus, even for infants just beginning to speak their first words, the way in which an object is named guides infants’ encoding, representation, and memory for that object.

Rapid automatized naming (RAN) tasks have been shown to be a strong correlate of reading abilities. RAN also predicts future reading across different ages, ability levels, and languages, and is often used in literacy screening. Thus, understanding the specific relations between early RAN and later reading difficulties is important. In this systematic review and meta-analysis (with N = 68 samples; k = 373 effect sizes; n = 10,513 participants), we test the extent to which measures of RAN assessed before grade school predict later reading performance in English-speaking children. We also test whether characteristics of the RAN tasks, reading measures, or sample demographics moderate this relationship. We found that kindergarten/preschool RAN is correlated with grade-school reading at r = -.38, similar in magnitude to previous meta-analyses that included various ages and languages. We found that alphanumeric RAN tasks are particularly strongly related to future reading, as compared with non-alphanumeric tasks (p = .01) but that other features of the RAN task, such as the number of items, do not alter its predictive significance. RAN predicts all types of reading measures, but more strongly predicts real word than nonword reading (p < .001). These results support a shared cognitive resource model in which the similarity between RAN and reading tasks accounts for their correlation. We provide practical guidelines based on these data for early screening for reading difficulties and dyslexia.

Despite the seemingly simple mapping between adjectives and perceptual properties (e.g., color, texture), preschool children have difficulty establishing the appropriate extension of novel adjectives. When children hear a novel adjective applied to an individual object, they successfully extend the adjective to other members of the same object category but have difficulty extending it more broadly to members of different categories. We propose that the source of this difficulty lies at the interface of the linguistic and conceptual systems: children initially limit the extension of an adjective to the category of the object on which it was introduced. To test this hypothesis, we manipulated whether participants construed images as “pictures of things” (objects) or “blobs of stuff” (non-objects). For both 36-month-old children (Experiments 1 and 2) and adults (Experiment 3), the conceptual status of an image influenced how they extended an adjective applied to that image. Children extended novel adjectives more successfully when they construed the images as non-objects than when they construed the same images as objects. Similarly, adults were faster to make adjective extensions when construing the images as non-objects rather than objects. Learners of all ages must navigate this linguistic-conceptual interface in assessing whether and how novel adjectives should be extended to new individuals.

Assessing infant category learning is a challenging but vital aspect of studying infant cognition. By employing a familiarization-test paradigm, we straightforwardly measure infants’ success in learning a novel category while relying only on their looking behavior. Moreover, the paradigm can directly measure the impact of different auditory signals on the infant categorization across a range of ages. For instance, we assessed how 2-year-olds learn categories in a variety of labeling environments: in our task, 2-year-olds successfully learned categories when all exemplars were labeled or the first two exemplars were labeled, but they failed to categorize when no exemplars were labeled or only the final two exemplars were labeled. To determine infants’ success in such tasks, researchers can examine both the overall preference displayed by infants in each condition and infants’ pattern of looking over the course of the test phase, using an eye-tracker to provide fine-grained time-course data. Thus, we present a powerful paradigm for identifying the role of language, or any auditory signal, in infants’ object category learning.

There is considerable evidence that labeling supports infants’ object categorization. Yet in daily life, most of the category exemplars that infants encounter will remain unlabeled. Inspired by recent evidence from machine learning, we propose that infants successfully exploit this sparsely labeled input through “semi-supervised learning.” Providing only a few labeled exemplars leads infants to initiate the process of categorization, after which they can integrate all subsequent exemplars, labeled or unlabeled, into their evolving category representations. Using a classic novelty preference task, we introduced 2-year-old infants (n = 96) to a novel object category, varying whether and when its exemplars were labeled. Infants were equally successful whether all exemplars were labeled (fully supervised condition) or only the first two exemplars were labeled (semi-supervised condition), but they failed when no exemplars were labeled (unsupervised condition). Furthermore, the timing of the labeling mattered: when the labeled exemplars were provided at the end, rather than the beginning, of familiarization (reversed semi-supervised condition), infants failed to learn the category. This provides the first evidence of semi-supervised learning in infancy, revealing that infants excel at learning from exactly the kind of input that they typically receive in acquiring real-world categories and their names.

Speakers can make inferences about the meaning of new words appearing in an utterance based on the lexical semantics of other words that co-occur with them. Previous work has revealed that infants at 19 and 24 months of age can recruit the semantic selectional restrictions of known verbs (e.g., eating) to deduce that a noun appearing in the subject position maps onto an animate referent. We asked whether this ability to capitalize on the semantics of familiar words to identify the referent of a novel noun in subject position extends to adjectives, which also denote properties, and which also have animacy constraints (e.g., hungry). We found that unlike in the previous studies with verbs, neither 24- nor 36-month-olds could successfully recruit known adjectival semantics in an online task to home in on an animate nominal referent. However, 36-month-olds were successful in a more interactive, forced-choice version of the task without such strict time limitations. We discuss multiple non-mutually-exclusive hypotheses for this pattern of results, focusing on the role of the morphosyntactic cues, the (lack of) perceptual cues for the target property in context of the utterance, truth conditions, and cross-linguistic implications. These possibilities raise fundamental questions about the infant’s developing lexicon and the linguistic and conceptual mechanisms at play in the process of word learning.