part of part of attached to attached to system anatomical structure cochlear duct of membranous labyrinth tectorial membrane of cochlea Wikipedia:Tectorial_membrane_(cochlea) The overlaying membrane of the cochlear duct, an extracellular matrix of the inner ear that contacts the stereocilia bundles of specialized sensory hair cells; sound induces movement of these hair cells relative to the tectorial membrane, deflects the stereocilia, and leads to fluctuations in hair cell membrane potential, transducing sound into electrical signals[MP,modified]. BIRNLEX:2531 FMA:75805 UBERON:0002233 UMLS:C1184928 NCIT:C33740 tectorial membrane of spiral organ of cochlea UMLS:C0039432 MA:0001199 MESH:D013680 in some squamate lineages, the tectorial membrane may not cover the whole cochlear duct/papilla. In some lineages, the tectorial membrane is divided into units called sallets[ISBN:9780387714691] GAID:876 SCTID:368960006 The tectorial membrane (TM) is one of two acellular gels in the cochlea of the inner ear, the other being the basilar membrane (BM). The TM is located above the sulcus spiralis internus and the spiral organ of Corti and extends along the longitudinal length of the cochlea parallel to the BM. Radially the TM is divided into three zones, the limbal, middle and marginal zones. Of these the limbal zone is the thinnest (transversally) and overlies the auditory teeth of Huschke with its inside edge attached to the spiral limbus. The marginal zone is the thickest (transversally) and is divided from the middle zone by Hensen's Stripe. It overlies the sensory inner hair cells and electrically-motile outer hair cells of the organ of Corti and during acoustic stimulation stimulates the inner hair cells through fluid coupling, and the outer hair cells via direct connection to their tallest stereocilia[Wikipedia:Tectorial_membrane_(cochlea)]. tectorial membrane EMAPA:35851 lamina of spiral limbus acellular membrane