Membrana basilar: Diferenzas entre revisións

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</ref> This causes sound input of a certain frequency to vibrate some locations of the membrane more than other locations. As shown in experiments by Nobel Prize laureate [[Georg von Békésy]], high frequencies lead to maximum vibrations at the basal end of the cochlear coil, where the membrane is narrow and stiff, and low frequencies lead to maximum vibrations at the apical end of the cochlear coil, where the membrane is wider and more compliant. This "place–frequency map" can be described quantitatively by the [[Greenwood function]] and its variants.
 
As vibracións orixinadas polo son viaxan como ondas ao longo das membranas, ao longo das cales, nos humanos, están dispostas nunha soa ringleira unha 3.500 [[célula ciliada interna|células ciliadas internas]]. Cada célula está unida a un diminutio armazón ou marco triangular. Os "cilios" son diminutos procesos situados na parte superior das células, que son moisensibles aosmovementos (estereocilios). Cando a vibración da membrana abanea os marcos triangulares, os cilios destas células son desprazados repetidamente, e iso produce corentes de pulsos que se envían polo nervio auditivo.<ref> Beament, James (2001). "How We Hear Music: the Relationship Between Music and the Hearing Mechanism". Woodbridge: Boydell Press. p. 97.</ref>
Sound-driven vibrations travel as waves along this membrane, along which, in humans, lie about 3,500 [[inner hair cell]]s spaced in a single row. Each cell is attached to a tiny triangular frame. The 'hairs' are minute processes on the end of the cell, which are very sensitive to movement. When the vibration of the membrane rocks the triangular frames, the hairs on the cells are repeatedly displaced, and that produces streams of corresponding pulses in the nerve fibers, which are transmitted to the auditory pathway.<ref>
{{Cite document
| last = Beament
| first = James
| title = How We Hear Music: the Relationship Between Music and the Hearing Mechanism
| place = Woodbridge
| publisher = Boydell Press
| year = 2001
| page = 97
| postscript = <!--None-->}}</ref>
The [[outer hair cell]]s feed back energy to amplify the traveling wave, by up to 65 dB at some locations.<ref>
{{cite journal |author=Nilsen KE, Russell IJ |title=Timing of cochlear feedback: spatial and temporal representation of a tone across the basilar membrane |journal=Nat. Neurosci. |volume=2 |issue=7 |pages=642–8 |year=1999 |pmid=10404197 |doi=10.1038/10197}}