What Do North American Babies Hear? A large-scale cross-corpus analysis.
Abstract
A range of demographic variables influences how much speech young children hear. However,
because studies have used vastly different sampling methods, quantitative comparison
of interlocking demographic effects has been nearly impossible, across or within studies.
We harnessed a unique collection of existing naturalistic, day-long recordings from
61 homes across four North American cities to examine language input as a function
of age, gender, and maternal education. We analyzed adult speech heard by 3- to 20-month-olds
who wore audio recorders for an entire day. We annotated speaker gender and speech
register (child-directed or adult-directed) for 10,861 utterances from female and
male adults in these recordings. Examining age, gender, and maternal education collectively
in this ecologically valid dataset, we find several key results. First, the speaker
gender imbalance in the input is striking: children heard 2-3× more speech from females
than males. Second, children in higher-maternal education homes heard more child-directed
speech than those in lower-maternal education homes. Finally, our analyses revealed
a previously unreported effect: the proportion of child-directed speech in the input
increases with age, due to a decrease in adult-directed speech with age. This large-scale
analysis is an important step forward in collectively examining demographic variables
that influence early development, made possible by pooled, comparable, day-long recordings
of children's language environments. The audio recordings, annotations, and annotation
software are readily available for reuse and reanalysis by other researchers.
Type
Journal articleSubject
HumansLanguage Development
Speech Perception
Sex Factors
Demography
Tape Recording
Adult
Child, Preschool
Infant
Educational Status
United States
Female
Male
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https://hdl.handle.net/10161/19713Published Version (Please cite this version)
10.1111/desc.12724Publication Info
Bergelson, Elika; Casillas, Marisa; Soderstrom, Melanie; Seidl, Amanda; Warlaumont,
Anne S; & Amatuni, Andrei (2019). What Do North American Babies Hear? A large-scale cross-corpus analysis. Developmental science, 22(1). pp. e12724. 10.1111/desc.12724. Retrieved from https://hdl.handle.net/10161/19713.This is constructed from limited available data and may be imprecise. To cite this
article, please review & use the official citation provided by the journal.
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Show full item recordScholars@Duke
Elika Bergelson
Crandall Family Assistant Professor
Dr. Bergelson accepts PhD applicants through the Developmental and Cog/CogNeuro areas
of P&N and the CNAP program.In my research, I try to understand the interplay of processes
during language acquisition. In particular, I am interested in how word learning relates
to other aspects of learning language (e.g. speech sound acquisition, grammar/morphology
learning), and social/cognitive development more broadly (e.g. joint attention processes)
in the first few

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