At birth, infants discriminate most of the sounds of the world’s languages, but by age 1, infants become language-specific listeners. This has generally been taken as evidence that infants have learned which acoustic dimensions are contrastive, or useful for distinguishing among the sounds of their language(s), and have begun focusing primarily on those dimensions when perceiving speech. However, speech is highly variable, with different sounds overlapping substantially in their acoustics, and after decades of research, we still do not know what aspects of the speech signal allow infants to differentiate contrastive from noncontrastive dimensions. Here we show that infants could learn which acoustic dimensions of their language are contrastive, despite the high acoustic variability. Our account is based on the cross-linguistic fact that even sounds that overlap in their acoustics differ in the contexts they occur in. We predict that this should leave a signal that infants can pick up on and show that acoustic distributions indeed vary more by context along contrastive dimensions compared with noncontrastive dimensions. By establishing this difference, we provide a potential answer to how infants learn about sound contrasts, a question whose answer in natural learning environments has remained elusive.
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This content will become publicly available on May 3, 2025
Does environmental education work differently across sociopolitical contexts in the United States? Part II. Examining pedagogy in school field trip programs for early adolescent youth across political contexts
- Award ID(s):
- 1906610
- PAR ID:
- 10516611
- Publisher / Repository:
- Routledge
- Date Published:
- Journal Name:
- Environmental Education Research
- Volume:
- 30
- Issue:
- 5
- ISSN:
- 1350-4622
- Page Range / eLocation ID:
- 753 to 774
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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