biostudies-literatureRaufer SNIDCD NIH HHSHHS | NIH | National Institute on Deafness and Other Communication Disorders13977-13982https://www.ebi.ac.uk/biostudies/studies/S-EPMC6628837biostudies-literatureUnknown116(28)Mammals detect sound through mechanosensitive cells of the cochlear organ of Corti that rest on the basilar membrane (BM). Motions of the BM and organ of Corti have been studied at the cochlear base in various laboratory animals, and the assumption has been that the cochleas of all mammals work similarly. In the classic view, the BM attaches to a stationary osseous spiral lamina (OSL), the tectorial membrane (TM) attaches to the limbus above the stationary OSL, and the BM is the major moving element, with a peak displacement near its center. Here, we measured the motion and studied the anatomy of the human cochlear partition (CP) at the cochlear base of fresh human cadaveric specimens. Unlike the classic view, we identified a soft-tissue structure between the BM and OSL in humans, which weProceedings of the National Academy of Sciences of the United States of AmericaCochlear partition anatomy and motion in humans differ from the classic view of mammals.PMC6628837R01DC013303R01 DC013303Raufer SGuinan JJNakajima HHfalseCochlear partition anatomy and motion in humans differ from the classic view of mammals.Mammals detect sound through mechanosensitive cells of the cochlear organ of Corti that rest on the basilar membrane (BM). Motions of the BM and organ of Corti have been studied at the cochlear base in various laboratory animals, and the assumption has been that the cochleas of all mammals work similarly. In the classic view, the BM attaches to a stationary osseous spiral lamina (OSL), the tectorial membrane (TM) attaches to the limbus above the stationary OSL, and the BM is the major moving element, with a peak displacement near its center. Here, we measured the motion and studied the anatomy of the human cochlear partition (CP) at the cochlear base of fresh human cadaveric specimens. Unlike the classic view, we identified a soft-tissue structure between the BM and OSL in humans, which we2019-01-01T00:00:00Z2019 Jul2025-04-05T16:21:48.496Z2025-04-05T16:21:48.496ZS-EPMC66288373123560110.1073/pnas.1900787116