Human and non-human primates produce rhythmical sounds as soon as they are born. These early vocalizations are important for soliciting the attention of caregivers. How they develop, remains a mystery. The orofacial movements necessary for producing these vocalizations have distinct spatiotemporal signatures. Therefore, their development could potentially be tracked over the course of prenatal life. We densely and longitudinally sampled fetal head and orofacial movements in marmoset monkeys using ultrasound imaging. We show that orofacial movements necessary for producing rhythmical vocalizations differentiate from a larger movement pattern that includes the entire head. We also show that signature features of marmoset infant contact calls emerge prenatally as a distinct pattern of orofacial movements. Our results establish that aspects of the sensorimotor development necessary for vocalizing occur prenatally, even before the production of sound.
All data generated or analysed during this study are available on DRYAD.https://doi.org/10.5061/dryad.m905qfv1x
Data from: Prenatal development of neonatal vocalizationsDryad Digital Repository, doi:10.5061/dryad.m905qfv1x.
- Asif A Ghazanfar
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All of the animals were handled according to approved institutional animal care and use committee (IACUC) protocols (#1908-18) of Princeton University.
- Andrew J King, University of Oxford, United Kingdom
- Received: March 9, 2022
- Accepted: July 11, 2022
- Accepted Manuscript published: July 26, 2022 (version 1)
© 2022, Narayanan et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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