PMID: 11605684Oct 19, 2001Paper

The pathway for the transmission of external sounds into the fetal inner ear

Journal of Basic and Clinical Physiology and Pharmacology
H Sohmer, S Freeman

Abstract

After at least 20 weeks gestation, the human fetus in utero is able to hear and respond to external and internal (maternal) sounds. The external sounds are attenuated by maternal tissues and fluids - higher frequencies by about 20 dB, and lower frequencies are only slightly reduced. The sounds in the amniotic fluid, which completely envelops the fetus, then reach the fetal inner ear by bone conduction. The sound pressure in the amniotic fluid induces skull vibrations which are transmitted directly into the contents of the cranial cavity (brain and CSF) and from there, presumably by fluid channels connecting them, into the cochlear fluids. A further stage of conductive attenuation is probably involved in this transmission. Since the fetus in utero receives oxygen by placental diffusion (less efficient than pulmonary diffusion), the fetal inner ear is hypoxic compared to that following birth (pulmonary oxygen diffusion). This leads to a reduction in the magnitude of the endocochlear potential, to a depression of cochlear transduction and amplification, and thus to an additional sensorineural component of threshold elevation in the fetus. Upon birth, these conductive and sensorineural attenuations are removed.

References

Jul 1, 1992·American Journal of Otolaryngology·K J GerhardtA J Peters
Feb 1, 1992·The Laryngoscope·P BonfilsP Narcy
Sep 1, 1991·Hearing Research·H Sohmer, S Freeman
Jan 1, 1985·Acta Oto-laryngologica. Supplementum·E W Rubel
Oct 1, 1985·The Journal of Pediatrics·S LaryV Dubowitz
Oct 1, 1967·Physiological Reviews·J MetcalfeW Moll
Jan 1, 1983·Hearing Research·H Davis
Jun 15, 1982·American Journal of Obstetrics and Gynecology·S R GelmanR M Abrams
Oct 15, 1981·American Journal of Obstetrics and Gynecology·M L ReussM A Heymann
Sep 1, 1994·Archives of Disease in Childhood. Fetal and Neonatal Edition·P G Hepper, B S Shahidullah
Feb 1, 1996·Seminars in Perinatology·K J Gerhardt, R M Abrams
Nov 1, 1996·American Journal of Otolaryngology·K J GerhardtP J Antonelli
Jan 7, 1999·European Journal of Pediatrics·P BrienesseC E Blanco
Jul 29, 2000·Hearing Research·H SohmerI Savion

❮ Previous
Next ❯

Citations

Jan 3, 2013·Acta Paediatrica·Minna Huotilainen
Jul 3, 2013·Developmental Psychobiology·Grace Y Lee, Barbara S Kisilevsky
Oct 3, 2006·Medical Hypotheses·Barbara S Kisilevsky, Gregory A L Davies
Nov 6, 2015·Ultrasound : Journal of the British Medical Ultrasound Society·Marisa López-TeijónAlberto Prats-Galino
Oct 4, 2017·Trends in Hearing·Haim Sohmer
Sep 3, 2004·Journal of Neurophysiology·Martin Pienkowski, Robert V Harrison
Sep 11, 2007·International Journal of Audiology·Andrej Kral
Feb 7, 2009·Journal of Perinatal Medicine·Sérgio Hecker LuzMárcia Lorena Fagundes Chaves
Oct 10, 2003·Neuroreport·Minna HuotilainenRisto Näätänen

❮ Previous
Next ❯

Related Concepts

Related Feeds

Auditory Perception

Auditory perception is the ability to receive and interpret information attained by the ears. Here is the latest research on factors and underlying mechanisms that influence auditory perception.

Related Papers

International Journal of Gynaecology and Obstetrics : the Official Organ of the International Federation of Gynaecology and Obstetrics
T M D'Hooghe, H J Odendaal
Journal of Basic and Clinical Physiology and Pharmacology
H Sohmer, S Freeman
© 2021 Meta ULC. All rights reserved