{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,20]],"date-time":"2026-09-20T08:34:58Z","timestamp":1789893298517,"version":"4.0.1"},"reference-count":55,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,7,15]],"date-time":"2026-07-15T00:00:00Z","timestamp":1784073600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000055","name":"National Institute on Deafness and Other Communication Disorders","doi-asserted-by":"publisher","award":["K01DC017812"],"award-info":[{"award-number":["K01DC017812"]}],"id":[{"id":"10.13039\/100000055","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Audiol. Otol."],"abstract":"<jats:p>\n                    The elephant's middle ear (ME) boasts ossicles approximately nine times more massive than humans', with eardrums seven times larger. These anatomical features contribute to enhanced low-frequency sensitivity to air-conducted (AC) sound, but their contribution to bone-conduction (BC) hearing is less understood. To characterize BC hearing in elephants, we employed 3D laser Doppler vibrometry to measure ossicular motion in cadaveric temporal bones from both African and Asian elephants, as well as humans in response to BC stimulation. We analyzed velocity measurements projected along the piston direction at the umbo, stapes, and cochlear promontory across a frequency range of 12\u201311,000 Hz. Differential velocity (V\n                    <jats:sub>diff<\/jats:sub>\n                    ) was calculated as the difference in the velocity of the piston (V\n                    <jats:sub>pist<\/jats:sub>\n                    ) and the velocity of the promontory (V\n                    <jats:sub>prom<\/jats:sub>\n                    ) divided by the velocity of the promontory [(V\n                    <jats:sub>pist<\/jats:sub>\n                    -V\n                    <jats:sub>prom<\/jats:sub>\n                    )\/V\n                    <jats:sub>prom<\/jats:sub>\n                    ]. V\n                    <jats:sub>diff<\/jats:sub>\n                    plateaued above the BC resonant frequency\u22121.2 kHz for humans, reflective of prior studies, and 400 Hz for elephants. Below their respective resonant frequencies, the stapes V\n                    <jats:sub>diff<\/jats:sub>\n                    magnitude for elephants was three to four times greater than that of humans, and both decreased at approximately 12 dB\/octave until about 200 Hz. Surprisingly, both elephant and humans exhibited a plateau in their stapes V\n                    <jats:sub>diff<\/jats:sub>\n                    below 200 Hz, rather than continuing to decrease at the 12 dB\/oct rate. This suggests that both species have better low-frequency sensitivity for bone conduction than previously predicted. These results indicate that the larger ossicular and eardrum mass distributions play a crucial role in lowering BC resonance and enhancing low-frequency sensitivity. Elephants may further enhance BC hearing below about 200 Hz by contracting a skeletal muscle that occludes the ear canal, achieving a similar result to the occlusion effect in humans. These mechanisms may explain elephants' ability to detect ground-borne acoustic signals over long distances.\n                  <\/jats:p>","DOI":"10.3389\/fauot.2026.1744613","type":"journal-article","created":{"date-parts":[[2026,7,15]],"date-time":"2026-07-15T06:06:11Z","timestamp":1784095571000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":1,"title":["Bone-conduction hearing in elephants and humans: a middle-ear comparative study"],"prefix":"10.3389","volume":"4","author":[{"given":"Caitlin E.","family":"O'Connell-Rodwell","sequence":"first","affiliation":[{"name":"Eaton-Peabody Laboratories, Massachusetts Eye and Ear, Boston","place":["MA, United States"]},{"name":"Department of Otolaryngology, Head & Neck Surgery, Harvard Medical School, Boston","place":["MA, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jodie L.","family":"Berezin","sequence":"additional","affiliation":[{"name":"Eaton-Peabody Laboratories, Massachusetts Eye and Ear, Boston","place":["MA, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anbuselvan","family":"Dharmarajan","sequence":"additional","affiliation":[{"name":"Eaton-Peabody Laboratories, Massachusetts Eye and Ear, Boston","place":["MA, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alessio","family":"Pignatelli","sequence":"additional","affiliation":[{"name":"Department of Biostatistics, Johns Hopkins University, Baltimore","place":["MD, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rachel","family":"Chen","sequence":"additional","affiliation":[{"name":"Eaton-Peabody Laboratories, Massachusetts Eye and Ear, Boston","place":["MA, United States"]},{"name":"Harvard Medical School, Boston","place":["MA, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Francisco","family":"Uzal","sequence":"additional","affiliation":[{"name":"School of Veterinary Medicine, University of California, Davis, Davis","place":["CA, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiying","family":"Guan","sequence":"additional","affiliation":[{"name":"Communication Sciences and Disorders, Wayne State University, Detroit","place":["MI, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sunil","family":"Puria","sequence":"additional","affiliation":[{"name":"Eaton-Peabody Laboratories, Massachusetts Eye and Ear, Boston","place":["MA, United States"]},{"name":"Department of Otolaryngology, Head & Neck Surgery, Harvard Medical School, Boston","place":["MA, United States"]},{"name":"Graduate Program in Speech and Hearing and Biosciences and Technologies, Harvard Medical School, Boston","place":["MA, United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,7,15]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"123","DOI":"10.1037\/0735-7036.116.2.123","article-title":"The properties of geophysical fields and their effects on elephants and other animals","volume":"116","author":"Arnason","year":"2002","journal-title":"J. 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