Code-switching (switching between languages) is a common linguistic behavior in bilingual speech directed to infants and children. In adult-directed speech (ADS), acoustic-phonetic properties of one language may transfer to the other language close to a code-switch point; for example, English stop consonants may be more Spanish-like near a switch.…

Examining how bilingual infants experience their dual language input is important for understanding bilingual language acquisition. To assess these language experiences, researchers typically conduct language interviews with caregivers. However, little is known about the reliability of these parent reports in describing how bilingual children…

Infants are sensitive to syllable co-occurrence probabilities when segmenting words from fluent speech. However, segmenting two languages overlapping at the syllabic level is challenging because the statistical cues across the languages are incongruent. Successful segmentation, thus, relies on infants' ability to separate language inputs and track…

Contemporary models of adult speech perception acknowledge that the processing of linguistic and nonlinguistic aspects of the speech signal are interdependent. But when in development does this interdependence first emerge? In the adult literature, one way to demonstrate this relationship has been to examine how language experience affects talker…

Infants are adept at learning statistical regularities in artificial language materials, suggesting that the ability to learn statistical structure may support language development. Indeed, infants who perform better on statistical learning tasks tend to be more advanced in parental reports of infants' language skills. Work with adults suggests…

Infants appear to progress from universal to language-specific event perception. In Japanese, two different verbs describe a person crossing a "bounded ground" (e.g., street) versus an unbounded ground (e.g., field) while in English, the same verb -- "crossing" -- describes both events. Interestingly, Japanese "and"…

When and how do infants learn color words? It is generally supposed that color words are learned late and with a great deal of difficulty. By examining infant language surveys in British English and 11 other languages, this study shows that color word learning occurs earlier than has been previously suggested and that the order of acquisition of…

Previous research shows that English-learning 7.5-month-olds are biased to segment speech at strong syllables consistent with the predominant trochaic (strong-weak) pattern of words in their language (Jusczyk, Houston, & Newsome, 1999). The present study asked whether 7.5-month-olds can use a familiar name to override their metrical bias and…

Infants struggle to understand familiar words spoken in unfamiliar accents. Here, we examine whether accent exposure facilitates accent-specific adaptation. Two types of pre-exposure were examined: video-based (i.e., listening to pre-recorded stories; Experiment 1) and live interaction (reading books with an experimenter; Experiments 2 and 3).…

Infants are sensitive to statistical regularities (i.e., transitional probabilities, or TPs) relevant to segmenting words in fluent speech. However, there is debate about whether tracking TPs results in representations of possible words. Infants show preferential learning of sequences with high TPs (HTPs) as object labels relative to those with…

Adults recognize talkers better when the talkers speak a familiar language than when they speak an unfamiliar language. This language familiarity effect (LFE) demonstrates the inseparable nature of linguistic and indexical information in adult spoken language processing. Relatively little is known about children's integration of linguistic and…

We assessed 24-month-old infants' lexical processing efficiency for both novel and familiar words. Prior work documented that 19-month-olds successfully identify referents of familiar words (e.g., The dog is so little) as well as novel words whose meanings were informed only by the surrounding sentence (e.g., The vep is crying), but that the speed…

We tested 12- and 18-month-old English-learning infants on a preferential-looking task which contrasted grammatically correct sentences using the determiner "the" vs. three ungrammatical conditions in which "the" was substituted by another English function word, a nonsense word, or omitted. Our design involved strict controls…

Purpose: This experiment examined English- or Spanish-learning preverbal (8-9 months, n = 32) and postverbal (12-14 months, n = 40) infants' learning of word-action pairings prior to and after the transition to verb comprehension and its relation to naturally learned vocabulary. Method: Infants of both verbal levels were first habituated to 2…

Word order is a core mechanism for conveying syntactic structure, yet interrogatives usually disrupt canonical word orders. For example, in English, polar interrogatives typically invert the subject and auxiliary verb and insert an utterance-initial "do" if no auxiliary is present. These word order patterns result from differences in the…