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Not AvailableThe goal of this research is to understand how bilingual and monolingual parents adjust their speech when talking to infants. We examined pitch characteristics of infant-directed speech (IDS) and adult-directed speech (ADS) with Spanish-English bilingual and English monolingual parents and their infants (8–20 months of age). Thirty-eight parent-infant dyads participated in two naturalistic play tasks. Parents spoke with a bilingual researcher to collect samples of ADS. Results showed that both parent groups produced higher maximum and average fundamental frequency in IDS than ADS, suggesting that caregivers adjust pitch similarly in IDS across registers. However, for bilinguals, the IDS versus ADS difference was larger in English than Spanish; bilingual parents differentiated IDS adjustments across languages. The analyses across word repetitions revealed that in bilingual parents’ IDS, there was no change in pitch across the first and second repetitions of target words, even when repetitions occurred in different languages. Taken together, results suggest that bilingual parents adjust their IDS pitch similarly to English-speaking monolinguals, but they differentiate English and Spanish IDS adjustments. Overall, this project contributes to our understanding of parents’ register adjustments across multilingual language learning contexts.
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The intelligibility of consonants in American English infant-directed speech
To begin learning their language, infants must locate words in the speech signal. Some models of word discovery presuppose that the discovery process depends on identifying phonetic segments (phones) in speech. To test the plausibility of models arguing that infants can reliably categorize consonants in speech, adult native speakers were asked to identify the consonant in vowel-consonant-vowel sequences extracted from spontaneous English infant-directed speech. Listeners could consistently identify some instances of consonants (for example, correctly indicating that an /s/ was an /s/). But many tokens (about half) were not consistently identifiable. Performance was significantly worse for codas than onsets. Providing the full utterance context in low-pass-filtered form did not aid recognition, nor did familiarization with the talker. In a second task, listeners were barely above chance in guessing whether a consonant was a word onset or a word-final coda. Performance on infant-directed speech was not markedly better than performance on a comparison set of adult-directed speech consonants. Erroneous responses frequently had little systematic resemblance to the correct answer. The results suggest that it is not plausible that infants can parse most utterances exhaustively into strings of uttered speech sounds and feed those strings into a statistical clustering mechanism.
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- PAR ID:
- 10668921
- Publisher / Repository:
- Publisher: Elsevier. Repository: OSF
- Date Published:
- Journal Name:
- Cognitive Psychology
- Volume:
- 161
- Issue:
- C
- ISSN:
- 0010-0285
- Page Range / eLocation ID:
- 101766
- Subject(s) / Keyword(s):
- language acquisition categorization speech phonetics unsupervised learning infant development
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1016/j.cogpsych.2025.101766
