PurposeThis study investigated whether the ability to utilize statistical regularities from fluent speech and map potential words to meaning at 18-months predicts vocabulary at 18- and again at 24-months.MethodEighteen-month-olds were exposed to an artificial language with statistical regularities within the speech stream, then participated in an object-label learning task. Learning was measured using a modified looking-while-listening eye-tracking design. Parents completed vocabulary questionnaires when their child was 18-and 24-months old.ResultsAbility to learn the object-label pairing for words after exposure to the artificial (...) language predicted productive vocabulary at 24-months and amount of vocabulary change from 18- to 24 months, independent of non-verbal cognitive ability, socio-economic status and/or object-label association performance.ConclusionEighteen-month-olds’ ability to use statistical information derived from fluent speech to identify words within the stream of speech and then to map the “words” to meaning directly predicts vocabulary size at 24-months and vocabulary change from 18 to 24 months. The findings support the hypothesis that statistical word segmentation is one of the important aspects of word learning and vocabulary acquisition in toddlers. (shrink)

Identifying the referent of novel words is a complex process that young children do with relative ease. When given multiple objects along with a novel word, children select the most novel item, sometimes retaining the word‐referent link. Prior work is inconsistent, however, on the role of object novelty. Two experiments examine 18‐month‐old children's performance on referent selection and retention with novel and known words. The results reveal a pervasive novelty bias on referent selection with both known and novel names and, (...) across individual children, a negative correlation between attention to novelty and retention of new word‐referent links. A computational model examines possible sources of the bias, suggesting novelty supports in‐the‐moment behavior but not retention. Together, results suggest that when lexical knowledge is weak, attention to novelty drives behavior, but alone does not sustain learning. Importantly, the results demonstrate that word learning may be driven, in part, by low‐level perceptual processes. (shrink)

Children and adults use established global knowledge to generate real‐time linguistic predictions, but less is known about how listeners generate predictions in circumstances that semantically conflict with long‐standing event knowledge. We explore these issues in adults and 5‐ to 10‐year‐old children using an eye‐tracked sentence comprehension task that tests real‐time activation of unexpected events that had been previously encountered in brief stories. Adults generated predictions for these previously unexpected events based on these discourse cues alone, whereas children overall did not (...) override their established global knowledge to generate expectations for semantically conflicting material; however, they do show an increased ability to integrate discourse cues to generate appropriate predictions for sentential endings. These results indicate that the ability to rapidly integrate and deploy semantically conflicting knowledge has a long developmental trajectory, with adult‐like patterns not emerging until later in childhood. (shrink)