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| | Institute of Phonetic Sciences, |
 | | However, this constant can be used to relate the behaviour of a point of the basilar membrane to a prescribed pressure at the stapes. | | | The solution of the membrane condition shows that after the point of resonance the level of the pressure is extremely small. | | | Secondly, both the filter characteristics for an arbitrary point of the membrane and the corresponding impulse response are determined. |
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http://fonsg3.let.uva.nl/Proceedings/Proceedings22/JanvDijk/JanvDijk1998.html
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| | Physiological Measures of Cochlear Mechanics - Scientific & Clinical Research - Boys Town National Research Hospital |
| | The significance of the differences between basilar membrane and IHC tuning is still a controversial issue. | | | The ability of OHCs to change their length in response to intracellular voltage changes provides clear evidence of electromechanic transduction within the cochlea and is believed to be the source of the basilar membrane compressive nonlinearity described above. | | | To measure cochlear responses that have normal characteristics, the cochlea must be kept in extremely good condition. |
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http://www.boystownhospital.org/BasicClinic/neuro/cel/Physiological.asp
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| | Chap VI |
| | This variation in width of the basilar membrane correlates with its variation in stiffness which, in turn, underlies the kind of mechanical motion it undergoes in response to sound waves. | | | The central processes of spiral ganglion neurons form the cochlear nerve and exit the temporal bone in the internal acoustic meatus. | | | This results in a systematic change in effective stiffness from base to apex. |
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http://www.neurophys.wisc.edu/h%26b/textbook/chap-6.html
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| | Smooth muscle membrane potential modulates endothelium-dependent relaxation of rat basilar artery via myo-endothelial ... |
| | In the present study, 4-AP was found to cause an impairment of agonist-induced, endothelium-dependent regulation of tone development in the rat basilar artery. | | | Although we found that 4-AP depressed ACh-induced endothelium-dependent relaxation of rat basilar artery, the data were not consistent with the view that K | | | ) channels by 4-aminopyridine (4-AP) on endothelium-dependent relaxation of rat basilar artery to acetylcholine (ACh) was assessed. |
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http://jp.physoc.org/cgi/content/full/545/3/975
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| | Do We Need Multiple Electrodes? |
| | In fact, when clearly thought through, it is apparent that it should be impossible to produce anything resembling pure tones in implant patients, tonotopically speaking, since even small fields are bound to spread across some substantial portion of the basilar membrane, stimulating areas associated with a spectrum of frequencies. | | | This would only make sense if we presume that we had to force much more current to flow between the closely paired electrodes, so that the field was in turn forced to grow so large that enough of it "leaked" to stimulate the cochlea more generally. | | | This makes a great deal of sense, at first glance: if the cochlea is like a piano keyboard, then, clearly, we need to stimulate the basilar membrane at the proper spot. |
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http://www.serve.com/~AllHear/monographs/WhyMultipleElectrodes.html
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| | Cochlear Implants: My Perspective, by Dr. William F. House (Chapter II) |
| | The most important of these, as I indicated in the introduction, is the apparent conflict between clinical observation and theory. | | | One must as a result either recognize that the tonotopic theory in all its potential variations is invalid, or reject the clinical data. | | | Original concept of the pathology of sensorineural deafness: hair cells are missing, but stimulable dendrites remain. |
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http://www.serve.com/AllHear/monographs/m-95-h02.html
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| | Cochlear Mechanics |
| | This behavior was tested by interferometric measurements based on laser beam reflections from two points, one on the basilar membrane, the other on the reticular lamina. | | | This effect was observed by Russell and Nilsen (1997). | | | The lever effect illustrated in the animation above was hypothesized in Mammano and Nobili (1993) and experimentally demonstrated in Mammano and Ashmore (1993); see Interferometry page, section |
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http://www.vimm.it/cochlea/cochleapages/theory/main.htm
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| | Sound intensity on the basilar membrane as square of amplitude on the eardrum |
| | Thus the static pressure component in the sound intensity signal on the basilar membrane is of utmost importance for the explanation of various phenomena in our hearing sense. | | | I don't think our ear can do it a factor of 10 better under ambient daily circumstances. | | | Noticeable physics and hearing aid considerations, ideas and reflections |
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http://www.slechthorend-plus.nl/fysica/en/heerens_02expl.htm
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| | NUIN Faculty - Mario Ruggero |
| | Using an exquisitely sensitive physical technique, laser velocimetry, we record sound-evoked vibrations of the basilar membrane which, at the threshold of hearing, are of atomic dimensions. | | | My research is focused on the cochlea, the mammalian hearing organ. | | | Using chinchillas as models of sensorineural ("nerve") deafness in humans, we have also shown that basilar-membrane vibrations are disrupted by agents such as intense noise or drugs which induce hair cell dysfunction. |
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http://www.northwestern.edu/nuin/faculty/Ruggero_M_A
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| | Free psychology essays |
| | Both of these models of frequency encoding have their limitations, in that neither can account for all of the pitch phenomena that have been observed by researchers. | | | Research such as that carried out by Sek and Moore (1995) found that for pure tones this is not the case. | | | Place theories account well for conditions such as the effects of basilar membrane damage; if a limited part of the basilar membrane is damaged, the patient will only lose sensitivity to a particular range of frequencies (Crowe, Guild and Polvost, 1934). |
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http://www.neocortex.co.uk/pitch.htm
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| | White Papers: Biophysics :DP bouncing phenomena in the cochlea |
| | The measurement was done for the post-exposure time without the low-frequency tone exposure. | | | The analysis of the 'bounce' recovery pattern from an individual ear will give information on the individual ability to recover from a temporal threshold shift objectively. | | | The nonlinearity at -1 minute post-exposure time indicated the basilar membrane nonlinearity before the low-frequency tone exposure and the nonlinearity from 20 second to 5.0 minutes indicated the basilar membrane nonlinearity after the low-frequency tone exposure. |
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http://www.otoemissions.org/whitepapers/biophysics/dpbounce.html
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| | HISTOLOGY |
| | These otoliths respond to gravity and detect positional changes during movement of the body. | | | There are no otoliths associated with the cupula. | | | The three bones are associated with 2 small skeletal muscles, the Tensor Tympani (attached to the malleus), and the Stapedius (attached to the stapes). |
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http://medic.med.uth.tmc.edu/Lecture/Main/ear.htm
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| | Publications of Professor Søren Buus |
| | The cochlear-map function is determined as a best-fitting function to physiological data relating characteristic frequency, CF, of auditory-nerve fibers to their place of innervation on the basilar papilla. | | | Excitation patterns are derived from auditory-nerve measurements of levels at CF necessary to produce firing rates equal to those evoked by a test tone. | | | Likewise, he suggested that discrimination of level differences between sounds could be understood on the basis of their excitation patterns. |
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http://www.cdsp.neu.edu/publications/buus
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| | AUDITORY AND VESTIBULAR PATHWAYS |
| | One theory to explain the mystery is that the outer hair cells help to "sharpen the tuning". | | | The entire fluid-filled structure is called the inner ear. | | | This means that the basilar membrane vibrates to high frequencies at the base of the cochlea and to low frequencies at the apex. |
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http://thalamus.wustl.edu/course/audvest.html
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| | Organ of Corti - Wikipedia, the free encyclopedia |
| | The organ of Corti is the sensitive element in the inner ear and can be thought of as the body's microphone. | | | Like other nerve cells, their response to stimulus is to send a tiny voltage pulse called an "action potential" down the associated nerve fiber (axon). | | | The place along the basilar membrane where maximum excitation of the hair cells occurs determines the perception of pitch according to the place theory. |
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http://en.wikipedia.org/wiki/Organ_of_Corti
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| | BrainConnection.com - How We Hear |
| | This gives the basilar membrane tonotopic organization or organization by tone, similar to a xylophone: tones are arranged from low frequency on one end to high frequency on the other (Figure 1). | | | One end of the basilar membrane vibrates most at low frequency tones, and the other end of the membrane vibrates most at high frequency tones. | | | The process of determining what a sound is begins at a flat sheet of tissue (in the cochlea of the inner ear) called the basilar membrane. |
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http://www.brainconnection.com/topics?main=anat/auditory-phys
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| | A.1 Basilar Membrane and Hair Cell Models |
| | Direct measurements of basilar membrane motion demonstrate that, at low sound levels, the response can be sharply tuned, becoming more broadly tuned at high levels. | | | This nonlinear tuning is due to the outer hair cells, which can both sense mechanical stimuli, and respond to changes in membrane potential with changes in length. | | | This novel form of electromotility is piezoelectric in nature allowing it to achieve very high velocities [. |
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http://www.isr.umd.edu/CAAR/proposal/1/node3.html
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| | AFM Help |
| | The order of the gamma tone filters basilar membrane model determines the number of filtering stages and so it determines the slope of the skirts of the attenuation function and their extent. | | | Order for the gamma tone filters - basilar membrane model. | | | The DSAM library provides other basilar membrane models that can be included into AFM with a little Matlab programming effort (see " Technical information ") |
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http://goethe.ira.uka.de/~feldbus/AFM/BMGammaT.html
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| | Basilar Membrane |
| | In response to sinusoidal pressure applied to the stapes (tones) the basilar membrane vibrates producing the phenomenon of traveling waves. | | | Part of the stiffness change is due to the increasing width of the membrane and part to its decreasing thickness. | | | Iurato S (1962) Functional implication of the nature and submicroscopic stucture of the tectorial and basilar membranes. |
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http://www.vimm.it/cochlea/cochleapages/theory/bm/bm.htm
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| | Basic auditory system |
| | The changing parameters lead to the desirable behavior of sorting out sounds by their frequencies or time scales. | | | At the base, the basilar membrane is most sensitive to high frequencies and most sensitive to low frequencies at the apex. | | | The inner hair cells detect the vibration of basilar membrane and convert the sound signal into neural system signal. |
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http://www.geocities.com/jfhuang2000/basic_as.html
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| | 1999; Factors influencing a psychophysical measure of basilar-membrane nonlinearity |
| | Physiological studies have shown that the response of the basilar membrane (BM) to tones at characteristic frequency (CF) is highly compressive, while the response to tones well below CF is linear. | | | The amount of compression at CF may be estimated psychophysically by comparing the slope of the growth-of-masking (GOM) function for an on-frequency masker with that for a masker well below the signal frequency. | | | Factors influencing a psychophysical measure of basilar-membrane nonlinearity |
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http://www.aro.org/archives/1999/92.html
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| | Contact |
| | The outer hair cells have the role of a muscle which can change the characteristics of the membrane adaptively, thus providing the amplification effect for low-level stimuli. | | | Communication of hair cell response to the nervous system is achieved via the auditory nerve. | | | It is known that the primary structure of the cochlea, the basilar membrane, carries out a frequency analysis of the incoming sound wave, such that each frequency within the auditory spectrum causes a maximum displacement to occur at a particular point on the membrane. |
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http://tomscarff.tripod.com/music/human_auditory_system.htm
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| | Publications |
| | Yasin, I., and Plack, C.J. âThe effects of a high-frequency suppressor on tuning curves and derived basilar membrane response functions,â J. Acoust. | | | We believe these are the first accurate measurements of basilar membrane nonlinearity that have been made in humans. | | | The nonlinearity is essential to the normal functioning of the cochlea and gives rise, amongst other things, to our high degree of "frequency selectivity" (our ability to hear out a sound of one frequency in the presence of sounds of different frequencies). |
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http://privatewww.essex.ac.uk/~cplack/basilar_membrane.html
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| | Inside the Cochlea - Scientific & Clinical Research - Boys Town National Research Hospital |
| | For example, the range of audible frequencies is about 20 Hz to 16 kHz in the human cochlea and about 100 Hz to 40kHz in the cat cochlea. | | | Each point on the basilar membrane is tuned to a different frequency, with a spatial gradient of about 0.2 octaves/mm for human, and about 0.32 octaves/mm for cat. | | | The outer hair cells (OHC), on the other hand, are innervated primarily by efferent nerve fibers, which receive neural signals from the brain. |
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http://www.boystownhospital.org/BasicClinic/neuro/cel/Inside_Cochlea.asp
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| | Electronic Journal of Differential Equations |
| | Curvature and measurement of curvature should be allowed in future models and experiments of the inner ear. | | | Comparison of the two models allows us to study the effect of the curvature of the basilar membrane on the range of the frequencies of hearing. | | | In the second model the basilar membrane is treated as a rectangular region. |
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http://ejde.math.txstate.edu/conf-proc/02/a3/abstr.html
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| | Auditory Physiolgy |
| | the basilar membrane is represented point for point on the auditory cortex. | | | The vibrations are transmitted to the basilar membrane (see diagram opposite) which in turn vibrates at a particular frequency, depending upon the position along its length {high frequencies vibrate the window end where the basilar membrane is narrow and thick, and low frequencies vibrate the apical end where the membrane is wide and thin}. | | | Information about the vibration at different locations along the basilar membrane is relayed to the auditory cortex by the nerves synapsing with the hair cells at those locations. |
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http://www.cf.ac.uk/biosi/staff/jacob/teaching/sensory/ear.html
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| | The Ear |
| | Because the position along the membrane corresponds to frequency this statement is equivalent to saying that a pure tone excites nerves corresponding to a band of frequencies about the pure tone resonance. | | | Even though the critical band is quite wide we are able to process the information given by the nerves in the basilar membrane to be able to discern very small differences between two pure tone frequencies. | | | Imagine listening to a pure tone of 640 Hz. |
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http://physics.mtsu.edu/~wmr/ear.htm
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| | THE PHYSIOLOGY OF HEARING |
| | There are two maculae located within the utricle and saccule of the vestibule. | | | The movement of the hairs develops receptor potentials that lead to the generation of nerve impulses. | | | The vibration is then picked up by the incus, which transmits the vibration to the stapes. |
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http://www.actx.edu/~dutton_ds/hearing.htm
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| | MEDICAL BIOLOGY: THE COCHLEA, HEARING, AND HEARING LOSS |
| | The fluid channels within the cochlea are stimulated by the vibrating stapes footplate through the membranous oval window at the base of the cochlea. | | | Sound waves stimulate the hair bundle to increase and decrease the probability that mechanically gated transduction channels are in the "open" state, with consequent changes in membrane potential [2,3]. | | | 3) Movements of the basilar membrane are sensed by a line of hair cells, which are attached to the top of the membrane in a matrix called "the organ of Corti". |
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http://scienceweek.com/2004/sb041001-5.htm
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| | Basilar membrane - Wikipedia, the free encyclopedia |
| | This causes sound input of a certain frequency to vibrate a particular location of the membrane more than other locations due to the physical property of | | | The localized vibration of the basilar membrane is then transduced into neural signals by the inner hair cells of the | | | The basilar membrane within the cochlea of the |
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http://en.wikipedia.org/wiki/Basilar_membrane
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| | Ear |
| | These bones form the linkage between the tympanic membrane and the oval window that leads to the inner ear. | | | When a region of the basilar membrane resonates, the hair cells in that region send nerve impulses to the brain, which are perceived as a sound of whatever pitch the hair cell is associated with. | | | The middle ear includes the eardrum ( tympanum or tympanic membrane) and the ossicles, three tiny bones of the middle ear. |
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http://www.brainyencyclopedia.com/encyclopedia/e/ea/ear.html
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| | Sound |
| | The motion of the tympanic membrane is amplified and transferred by the bone structure collectively called the ossicles to the oval window (see figure to right). | | | As the basilar membrane oscillates the imbedded hair cells, whose cilia at the tips are imbedded in the stationary tectorial membrane, are "tweaked." This generates an action potential in the hair cells, which relays the information to the brain. | | | This causes a maximal displacement in different part of the membrane for a particular frequency. |
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http://ffden-2.phys.uaf.edu/213.web.stuff/Ameen%20Ashraf/Sound
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| | University Of Michigan Scientists Develop First Micro-machined Mechanical Cochlea |
| | This process allows the device to separate different frequency tones. | | | In the biological cochlea, the basilar membrane, which winds along the cochlear spiral, is stiffer at the base and becomes softer as it approaches the center. | | | A key feature is the exponentially tapered membrane width, which provides the varying acoustic impedance needed for cochlear-like frequency-position mapping. |
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http://www.sciencedaily.com/releases/2005/02/050205104015.htm
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| | Resonance |
| | In physics, resonance is an increase in the oscillatory energy absorbed by a system when the frequency of the oscillations matches the system's natural frequency of vibration (its resonant frequency). | | | Resonance is an important consideration for instrument builders as most acoustic instruments utilize resonators, such as the strings and body of a violin, the length of tube in a flute, and the shape of a drum membrane. | | | Violin (or harp, guitar, piano, etc.) strings have a fundamental resonant frequency directly related to the length and tension of the string. |
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http://www.sciencedaily.com/encyclopedia/resonance
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| | Mechanical ear makes its debut (January 2005) - News - PhysicsWeb |
| | The cochlea can be thought of as being divided into two channels by a flexible basilar membrane. | | | This movement is then detected by sensory hair cells on the membrane (figure 2). | | | Our ears can distinguish between different tones or frequencies because the waves created by high frequencies have a maximum near the base of the cochlea, while lower frequencies travel further towards the apex. |
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http://physicsweb.org/articles/news/9/1/12/1
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| | Scientists building a better bionic ear - LiveScience - MSNBC.com |
| | The surface of the basilar membrane is covered with tens of thousands of hairlike fibers that vibrate like miniature tuning forks when sound waves of specific frequencies pass over them. | | | These physical differences allow the basilar membrane to separate and transmit sounds according to their frequency. | | | In the human version, the end of the basilar membrane closest to the eardrum is narrow and taut and covered with fibers that are short and stiff, while the other end is wider and more flexible, covered with fibers that are longer and more limber. |
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http://www.msnbc.msn.com/id/6953604
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| | basilar membrane definition |
| | The membrane beneath hair cells in the cochlea of the inner ear that vibrates in response to sound. |
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http://www.biochem.northwestern.edu/holmgren/Glossary/Definitions/Def-B/basilar_membrane.html
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| | MSN Encarta - Membrane |
| | Membrane (Latin membrana, âparchmentâ), in biology, any thin layer of connective tissue coating individual cells and organs of the body, or lining the... | | | Become a subscriber today and gain access to: |
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http://encarta.msn.com/encyclopedia_761556947/Membrane.html
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| | INNER EAR |
| | The diagram below illustrates the idea that the basilar membrane bends most at different locations in response to different sound frequencies. | | | When sound activates the inner ear, the basilar membrane bends, and the hair cells on it are stimulated to generate neural signals. | | | Arranged along the length of the basilar membrane are about 40,000 hair cells, These are the receptors that transduce (convert) sound energy into neural signals. |
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http://www.indiana.edu/~p1013447/dictionary/in_ear.htm
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| | basilar membrane - definition from Biology-Online.org |
| | A membrane in the cochlea that supports the Organ of Corti. | | | The tissue in the cochlea of the ear that hosts the auditory hair cells that pick up vibrations caused by sound. | | | A thin layer of tissue covered with mesothelial cells that separates the cochlea from the scala tympani in the ear. |
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http://www.biology-online.org/dictionary/basilar_membrane
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| | membrane - definition of membrane in the Medical dictionary - by the Free Online Medical Dictionary, Thesaurus and ... |
| | This information should not be considered complete, up to date, and is not intended to be used in place of a visit, consultation, or advice of a legal, medical, or any other professional. | | | membrane - definition of membrane in the Medical dictionary - by the Free Online Medical Dictionary, Thesaurus and Encyclopedia. | | | A thin pliable layer of tissue covering surfaces, enveloping a part, lining a cavity, or separating or connecting structures or organs. |
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http://medical-dictionary.thefreedictionary.com/membrane
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| | Dynamic animation of the BM |
| | Sound-induced mechanical vibrations of the middle ear are transmitted into the fluid-filled cochlea, and generate the movement of the basilar membrane (BM). | | | This result indicates that the OHCs amplify the BM vibrations. | | | Dynamic animation of the BM Dynamic animation of the basilar membrane |
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http://www.wadalab.mech.tohoku.ac.jp/FEM_BM-e.html
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| | H.E.A.R. Articles Hearing Education and Awareness for Rockers |
| | This creates a shearing force between the basilar membrane and the tectoral membrane, causing the hair cell stereocilia to bend back and forth. | | | This pushes against the tectoral membrane, selectively amplifying the vibration of the basilar membrane. | | | This allows us to hear very quiet sounds. |
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http://www.hearnet.com/features/articles/artist_article_hearhair.shtml
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