ArticlePhilosophical transactions of the Royal Society of London. Series B, Biological sciences2021
Protophones, the precursors to speech, dominate the human infant vocal landscape.
Article in Philosophical transactions of the Royal Society of London. Series B, Biological sciences, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 28 papers, 1 of them a synthesis that pooled it.
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Who cites it
28 citing papers in PubMed, 1 synthesis or guideline pooled it, 62 citations in OpenAlex.
- From data to discovery: Technology propels speech-language research and theory-building in developmental science.Neuroscience and biobehavioral reviews · 2025Pooled it
- Many Moving Parts: A Motor-Based Perspective on Developmental Speech and Language Research in Neurodevelopmental Disorders.Journal of speech, language, and hearing research : JSLHR · 2026Article
- Ecologically-grounded observations offer unique insights into the embodied and embedded nature of infant learning.Human development · 2026Article
- Toward a Fuller Integration of Respiratory Rhythms Into Research on Infant Vocal and Motor Development.Annals of the New York Academy of Sciences · 2026Review
- Vocalisations are coupled with movement of all limbs throughout infancy.Scientific reports · 2025Article
- Evaluating canonical babbling ratios extracted from day-long audio recordings in infants later diagnosed with autism spectrum disorder.Infant behavior & development · 2025Article
- The robustness of speech-like vocalization in typically developing infants and infants with autism.Research in developmental disabilities · 2025Article
- Foundations of Vocal Category Development in Autistic Infants.Journal of autism and developmental disorders · 2025Article
- Article
- Pitch characteristics of real-world infant-directed speech vary with pragmatic context, perceived adult gender, and infant gender.PloS one · 2025Article
- Canonical babbling trajectories across the first year of life in autism and typical development.Autism : the international journal of research and practice · 2024Article
- Acoustic features of vocalizations in typically developing and autistic infants in the first year.Research in developmental disabilities · 2024Article
- Acoustic behavior of humpback whale calves on the feeding ground: Comparisons across age and implications for vocal development.PloS one · 2024Article
- From emotional signals to symbols.Frontiers in psychology · 2024Article
- Profiling the Longitudinal Development of Babbling in Infants with Cerebral Palsy: Validation of the Infant Monitor of Vocal Production (IMP) Using the Stark Assessment of Early Vocal Development-Revised (SAEVD-R).Diagnostics (Basel, Switzerland) · 2023Article
- Vocal Characteristics of Infants at Risk for Speech Motor Involvement: A Scoping Review.Journal of speech, language, and hearing research : JSLHR · 2023Article
- Marginal and Canonical Babbling in 10 Infants at Risk for Cerebral Palsy.American journal of speech-language pathology · 2023Article
- Preverbal infants produce more protophones with artificial objects compared to natural objects.Scientific reports · 2023Article
- Article
- The timeline of non-vocal and vocal communicative skills in infants with hearing loss.Frontiers in pediatrics · 2023Article
Corrections and comments
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Authors and funding
5 authors at 3 institutions in 3 countries.
Funding
Abstract
Human infant vocalization is viewed as a critical foundation for vocal learning and language. All apes share distress sounds (shrieks and cries) and laughter. Another vocal type, speech-like sounds, common in human infants, is rare but not absent in other apes. These three vocal types form a basis for especially informative cross-species comparisons. To make such comparisons possible we need empirical research documenting the frequency of occurrence of all three. The present work provides a comprehensive portrayal of these three vocal types in the human infant from longitudinal research in various circumstances of recording. Recently, the predominant vocalizations of the human infant have been shown to be speech-like sounds, or 'protophones', including both canonical and non-canonical babbling. The research shows that protophones outnumber cries by a factor of at least five based on data from random-sampling of all-day recordings across the first year. The present work expands on the prior reports, showing the protophones vastly outnumber both cry and laughter in both all-day and laboratory recordings in various circumstances. The data provide new evidence of the predominance of protophones in the infant vocal landscape and illuminate their role in human vocal learning and the origin of language. This article is part of the theme issue 'Vocal learning in animals and humans'.
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Registered trials
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