Day by day, hour by hour: Naturalistic language input to infants.
Abstract
Measurements of infants' quotidian experiences provide critical information about
early development. However, the role of sampling methods in providing these measurements
is rarely examined. Here we directly compare language input from hour-long video-recordings
and daylong audio-recordings within the same group of 44 infants at 6 and 7 months.
We compared 12 measures of language quantity and lexical diversity, talker variability,
utterance-type, and object presence, finding moderate correlations across recording-types.
However, video-recordings generally featured far denser noun input across these measures
compared to the daylong audio-recordings, more akin to 'peak' audio hours (though
not as high in talkers and word-types). Although audio-recordings captured ~10 times
more awake-time than videos, the noun input in them was only 2-4 times greater. Notably,
whether we compared videos to daylong audio-recordings or peak audio times, videos
featured relatively fewer declaratives and more questions; furthermore, the most common
video-recorded nouns were less consistent across families than the top audio-recording
nouns were. Thus, hour-long videos and daylong audio-recordings revealed fairly divergent
pictures of the language infants hear and learn from in their daily lives. We suggest
that short video-recordings provide a dense and somewhat different sample of infants'
language experiences, rather than a typical one, and should be used cautiously for
extrapolation about common words, talkers, utterance-types, and contexts at larger
timescales. If theories of language development are to be held accountable to 'facts
on the ground' from observational data, greater care is needed to unpack the ramifications
of sampling methods of early language input.
Type
Journal articlePermalink
https://hdl.handle.net/10161/19714Published Version (Please cite this version)
10.1111/desc.12715Publication Info
Bergelson, Elika; Amatuni, Andrei; Dailey, Shannon; Koorathota, Sharath; & Tor, Shaelise (2019). Day by day, hour by hour: Naturalistic language input to infants. Developmental science, 22(1). pp. e12715. 10.1111/desc.12715. Retrieved from https://hdl.handle.net/10161/19714.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
Associate Research Professor of Psychology and Neuroscience
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
Shannon Dailey
Postdoctoral Associate
Shannon is a Postdoctoral Associate in the Sanford School of Public Policy, working
on Baby's First Years with Dr. Lisa Gennetian. Shannon's research examines children's
language input and their developing language skills over time using various behavioral
methods. She is interested in how children’s early language experience varies systematically
between children and families (such as by child gender or family socioeconomic status)
and how that affects children's language development.
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