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Hrncirik F, Roberts I, Sevgili I, Swords C, Bance M. Models of Cochlea Used in Cochlear Implant Research: A Review. Ann Biomed Eng 2023; 51:1390-1407. [PMID: 37087541 PMCID: PMC10264527 DOI: 10.1007/s10439-023-03192-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Accepted: 03/20/2023] [Indexed: 04/24/2023]
Abstract
As the first clinically translated machine-neural interface, cochlear implants (CI) have demonstrated much success in providing hearing to those with severe to profound hearing loss. Despite their clinical effectiveness, key drawbacks such as hearing damage, partly from insertion forces that arise during implantation, and current spread, which limits focussing ability, prevent wider CI eligibility. In this review, we provide an overview of the anatomical and physical properties of the cochlea as a resource to aid the development of accurate models to improve future CI treatments. We highlight the advancements in the development of various physical, animal, tissue engineering, and computational models of the cochlea and the need for such models, challenges in their use, and a perspective on their future directions.
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Affiliation(s)
- Filip Hrncirik
- Cambridge Hearing Group, Cambridge, UK.
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, CB2 0QQ, UK.
| | - Iwan Roberts
- Cambridge Hearing Group, Cambridge, UK
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, CB2 0QQ, UK
| | - Ilkem Sevgili
- Cambridge Hearing Group, Cambridge, UK
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, CB2 0QQ, UK
| | - Chloe Swords
- Cambridge Hearing Group, Cambridge, UK
- Department of Physiology, Development and Neurosciences, University of Cambridge, Cambridge, CB2 3DY, UK
| | - Manohar Bance
- Cambridge Hearing Group, Cambridge, UK
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, CB2 0QQ, UK
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2
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Putzeys T, Borgers C, Fierens G, Walraevens J, Van Wieringen A, Verhaert N. Intracochlear pressure as an objective measure for perceived loudness with bone conduction implants. Hear Res 2022; 422:108550. [PMID: 35689853 DOI: 10.1016/j.heares.2022.108550] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 05/25/2022] [Accepted: 05/28/2022] [Indexed: 01/18/2023]
Abstract
BACKGROUND The generally accepted method to assess the functionality of novel bone conduction implants in a preclinical stage is to experimentally measure the vibratory response of the cochlear promontory. Yet, bone conduction of sound is a complex propagation phenomenon, depending on both frequency and amplitude, involving different conduction pathways. OBJECTIVES The aim of this study is to validate the use of intracochlear sound pressure (ICP) as an objective indicator for perceived loudness for bone conduction stimulation. It is investigated whether a correlation exists between intracochlear sound pressure measurements in cadaveric temporal bones and clinically obtained results using the outcome of a loudness balancing experiment. METHODS Ten normal hearing subjects were asked to balance the perceived loudness between air conducted (AC) sound and bone conducted (BC) sound by changing the AC stimulus. Mean balanced thresholds were calculated and used as stimulation levels in a cadaver trial (N = 4) where intracochlear sound pressure was measured during AC and BC stimulation to assess the correlation with the measured clinical data. The intracochlear pressure was measured at the relatively low stimulation amplitude of 80 dBHL using a lock-in amplification technique. RESULTS Applying AC and BC stimulation at equal perceived loudness on cadaveric heads yield a similar differential intracochlear pressure, with differences between AC and BC falling within the range of variability of normal hearing test subjects. CONCLUSION Comparing the perceived loudness at 80 dB HL for both AC and BC validates intracochlear pressure as an objective indicator of the cochlear drive. The measurement setup is more time-intensive than measuring the vibratory response of the cochlear promontory, yet it provides direct information on the level of the cochlear scalae.
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Affiliation(s)
- Tristan Putzeys
- KU Leuven - University of Leuven, Department of Neurosciences, ExpORL, B-3000 Leuven, Belgium; KU Leuven - University of Leuven, Department of Physics and Astronomy, Laboratory for Soft Matter and Biophysics, Heverlee, Belgium.
| | - Charlotte Borgers
- KU Leuven - University of Leuven, Department of Neurosciences, ExpORL, B-3000 Leuven, Belgium
| | - Guy Fierens
- KU Leuven - University of Leuven, Department of Neurosciences, ExpORL, B-3000 Leuven, Belgium; KU Leuven - University of Leuven, Department of Physics and Astronomy, Laboratory for Soft Matter and Biophysics, Heverlee, Belgium; Cochlear Technology Centre, Mechelen, Belgium
| | | | - Astrid Van Wieringen
- KU Leuven - University of Leuven, Department of Neurosciences, ExpORL, B-3000 Leuven, Belgium
| | - Nicolas Verhaert
- KU Leuven - University of Leuven, Department of Neurosciences, ExpORL, B-3000 Leuven, Belgium; University Hospitals Leuven, Department of Otorhinolaryngology, Head and Neck Surgery, Leuven, Belgium
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3
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Signatures of cochlear processing in neuronal coding of auditory information. Mol Cell Neurosci 2022; 120:103732. [PMID: 35489636 DOI: 10.1016/j.mcn.2022.103732] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2021] [Revised: 04/19/2022] [Accepted: 04/21/2022] [Indexed: 11/22/2022] Open
Abstract
The vertebrate ear is endowed with remarkable perceptual capabilities. The faintest sounds produce vibrations of magnitudes comparable to those generated by thermal noise and can nonetheless be detected through efficient amplification of small acoustic stimuli. Two mechanisms have been proposed to underlie such sound amplification in the mammalian cochlea: somatic electromotility and active hair-bundle motility. These biomechanical mechanisms may work in concert to tune auditory sensitivity. In addition to amplitude sensitivity, the hearing system shows exceptional frequency discrimination allowing mammals to distinguish complex sounds with great accuracy. For instance, although the wide hearing range of humans encompasses frequencies from 20 Hz to 20 kHz, our frequency resolution extends to one-thirtieth of the interval between successive keys on a piano. In this article, we review the different cochlear mechanisms underlying sound encoding in the auditory system, with a particular focus on the frequency decomposition of sounds. The relation between peak frequency of activation and location along the cochlea - known as tonotopy - arises from multiple gradients in biophysical properties of the sensory epithelium. Tonotopic mapping represents a major organizational principle both in the peripheral hearing system and in higher processing levels and permits the spectral decomposition of complex tones. The ribbon synapses connecting sensory hair cells to auditory afferents and the downstream spiral ganglion neurons are also tuned to process periodic stimuli according to their preferred frequency. Though sensory hair cells and neurons necessarily filter signals beyond a few kHz, many animals can hear well beyond this range. We finally describe how the cochlear structure shapes the neural code for further processing in order to send meaningful information to the brain. Both the phase-locked response of auditory nerve fibers and tonotopy are key to decode sound frequency information and place specific constraints on the downstream neuronal network.
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Braga J, Samir C, Fradi A, Feunteun Y, Jakata K, Zimmer VA, Zipfel B, Thackeray JF, Macé M, Wood BA, Grine FE. Cochlear shape distinguishes southern African early hominin taxa with unique auditory ecologies. Sci Rep 2021; 11:17018. [PMID: 34426640 PMCID: PMC8382707 DOI: 10.1038/s41598-021-96543-w] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Accepted: 08/11/2021] [Indexed: 02/07/2023] Open
Abstract
Insights into potential differences among the bony labyrinths of Plio-Pleistocene hominins may inform their evolutionary histories and sensory ecologies. We use four recently-discovered bony labyrinths from the site of Kromdraai to significantly expand the sample for Paranthropus robustus. Diffeomorphometry, which provides detailed information about cochlear shape, reveals size-independent differences in cochlear shape between P. robustus and Australopithecus africanus that exceed those among modern humans and the African apes. The cochlea of P. robustus is distinctive and relatively invariant, whereas cochlear shape in A. africanus is more variable, resembles that of early Homo, and shows a degree of morphological polymorphism comparable to that evinced by modern species. The curvature of the P. robustus cochlea is uniquely derived and is consistent with enhanced sensitivity to low-frequency sounds. Combined with evidence for selection, our findings suggest that sound perception shaped distinct ecological adaptations among southern African early hominins.
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Affiliation(s)
- J. Braga
- grid.15781.3a0000 0001 0723 035XCentre d’Anthropobiologie et de Génomique de Toulouse, Université Paul Sabatier Toulouse III, Faculté de Médecine Purpan, 37 allées Jules Guesde, Toulouse, France ,grid.11951.3d0000 0004 1937 1135Evolutionary Studies Institute, University of the Witwatersrand, PO WITS, Johannesburg, 2050 South Africa
| | - C. Samir
- grid.503317.30000 0000 9971 4898LIMOS, UMR 6158 CNRS-Université Clermont Auvergne, 63173 Aubière, France
| | - A. Fradi
- grid.503317.30000 0000 9971 4898LIMOS, UMR 6158 CNRS-Université Clermont Auvergne, 63173 Aubière, France
| | - Y. Feunteun
- grid.503317.30000 0000 9971 4898LIMOS, UMR 6158 CNRS-Université Clermont Auvergne, 63173 Aubière, France
| | - K. Jakata
- grid.11951.3d0000 0004 1937 1135Evolutionary Studies Institute, University of the Witwatersrand, PO WITS, Johannesburg, 2050 South Africa
| | - V. A. Zimmer
- grid.6936.a0000000123222966Faculty of Informatics, Technical University of Munich, Munich, Germany
| | - B. Zipfel
- grid.11951.3d0000 0004 1937 1135Evolutionary Studies Institute, University of the Witwatersrand, PO WITS, Johannesburg, 2050 South Africa
| | - J. F. Thackeray
- grid.11951.3d0000 0004 1937 1135Evolutionary Studies Institute, University of the Witwatersrand, PO WITS, Johannesburg, 2050 South Africa
| | - M. Macé
- Véto 31, 73 Avenue du Général de Gaulle, 47000 Agen, France
| | - B. A. Wood
- grid.253615.60000 0004 1936 9510Center for the Advanced Study of Human Paleobiology, George Washington University, Washington, DC 20052 USA
| | - F. E. Grine
- grid.36425.360000 0001 2216 9681Department of Anthropology, Stony Brook University, Stony Brook, NY 11794 USA ,grid.36425.360000 0001 2216 9681Department of Anatomical Sciences, Stony Brook University, Stony Brook, NY 11794 USA
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Finite element simulation of cochlear traveling wave under air and bone conduction hearing. Biomech Model Mechanobiol 2021; 20:1251-1265. [PMID: 33786715 DOI: 10.1007/s10237-021-01443-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Accepted: 02/22/2021] [Indexed: 10/21/2022]
Abstract
Besides the normal hearing pathway known as air conduction (AC), sound can also transmit to the cochlea through the skull, known as bone conduction (BC). During BC stimulation, the cochlear walls demonstrate rigid body motion (RBM) and compressional motion (CPM), both inducing the basilar membrane traveling wave (TW). Despite numerous measuring and modeling efforts for the TW phenomenon, the mechanism remains unclear, especially in the case of BC. This paper proposes a 3D finite element cochlea model mimicking the TW under BC. The model uses a traditional "box model" form, but in a spiral shape, with two fluid chambers separated by the long and flexible BM. The cochlear fluid was enclosed by bony walls, the oval and round window membranes. Contingent boundary conditions and stimulations are introduced according to the physical basis of AC and BC. Particularly for BC, both RBM and CPM of the cochlea walls are simulated. Harmonic numerical solutions are obtained at multiple frequencies among the hearing range. The BM vibration amplitude ([Formula: see text]) and its relation with volume displacement difference between the oval and round windows [Formula: see text], as well as the pressure difference at the base of the cochlea ([Formula: see text]), are analyzed. The simulated BM response at 12 mm from the base is peaked at about 3 k Hz, which is consistent with published experimental data. The TW properties under AC and BC are the same and have a common mechanism. (1) [Formula: see text] is proportional to [Formula: see text] at low frequencies. (2) [Formula: see text] is also proportional to [Formula: see text], within 5 dB error at high frequencies such as 16 k Hz. This study partly reveals the common quantitative relations between the TW and related factors under AC and BC hearing.
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Ni G, Pang J, Zheng Q, Xu Z, Liu B, Zhang H, Ming D. Modeling cochlear micromechanics: hypotheses and models. JOURNAL OF BIO-X RESEARCH 2019. [DOI: 10.1097/jbr.0000000000000034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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Bell A, Wit HP. Cochlear impulse responses resolved into sets of gammatones: the case for beating of closely spaced local resonances. PeerJ 2018; 6:e6016. [PMID: 30515362 PMCID: PMC6266938 DOI: 10.7717/peerj.6016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2018] [Accepted: 10/27/2018] [Indexed: 02/05/2023] Open
Abstract
Gammatones have had a long history in auditory studies, and recent theoretical work suggests they may play an important role in cochlear mechanics as well. Following this lead, the present paper takes five examples of basilar membrane impulse responses and uses a curve-fitting algorithm to decompose them into a number of discrete gammatones. The limits of this ‘sum of gammatones’ (SOG) method to accurately represent the impulse response waveforms were tested and it was found that at least two and up to six gammatones could be isolated from each example. Their frequencies were stable and largely independent of stimulus parameters. The gammatones typically formed a regular series in which the frequency ratio between successive members was about 1.1. Adding together the first few gammatones in a set produced beating-like waveforms which mimicked waxing and waning, and the instantaneous frequencies of the waveforms were also well reproduced, providing an explanation for frequency glides. Consideration was also given to the impulse response of a pair of elastically coupled masses—the basis of two-degree-of-freedom models comprised of coupled basilar and tectorial membranes—and the resulting waveform was similar to a pair of beating gammatones, perhaps explaining why the SOG method seems to work well in describing cochlear impulse responses. A major limitation of the SOG method is that it cannot distinguish a waveform resulting from an actual physical resonance from one derived from overfitting, but taken together the method points to the presence of a series of closely spaced local resonances in the cochlea.
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Affiliation(s)
- Andrew Bell
- John Curtin School of Medical Research, Australian National University, Canberra, ACT, Australia
| | - Hero P Wit
- Department of Otorhinolaryngology/Head and Neck Surgery, University of Groningen, Groningen, Netherlands
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Lee JH, Lee MY, Lim Y, Knowles J, Kim HW. Auditory disorders and future therapies with delivery systems. J Tissue Eng 2018; 9:2041731418808455. [PMID: 30397431 PMCID: PMC6207966 DOI: 10.1177/2041731418808455] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Accepted: 09/14/2018] [Indexed: 12/24/2022] Open
Abstract
Auditory function takes a major part in human life. While sensorineural hearing loss is related with many factors including genetic disorders, age and noise, the clear causes are not well understood. Even more, the currently available treatments with drugs cause side effects, which thus are considered suboptimal. Here, we communicate the delivery systems with biomaterials that can be possible therapeutic options to restore hearing and vestibular functions. We introduce briefly the various pathological factors related with hearing loss and the limitation of current therapies, detail the recent studies on delivery systems including nanoparticles and hydrogels and discuss future clinical availability.
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Affiliation(s)
- Jung-Hwan Lee
- Institute of Tissue Regeneration Engineering (ITREN), Dankook University, Cheonan, Republic of Korea.,Department of Biomaterials Science, College of Dentistry, Dankook University, Cheonan, Republic of Korea.,UCL Eastman - Korea Dental Medicine Innovation Center, Dankook University, Cheonan, Republic of Korea
| | - Min Young Lee
- Beckman Laser Institute Korea, College of Medicine, Dankook University, Cheonan, Republic of Korea.,Department of Otolaryngology-Head & Neck Surgery, College of Medicine, Dankook University, Cheonan, Republic of Korea
| | - Yohan Lim
- Institute of Tissue Regeneration Engineering (ITREN), Dankook University, Cheonan, Republic of Korea
| | - Jonathan Knowles
- UCL Eastman - Korea Dental Medicine Innovation Center, Dankook University, Cheonan, Republic of Korea.,Department of Nanobiomedical Science and BK21 PLUS NBM Global Research Center for Regenerative Medicine, Dankook University, Cheonan, Republic of Korea.,Biomaterials and Tissue Engineering Research Department, UCL Eastman Dental Institute, London, UK.,The Discoveries Centre for Regenerative and Precision Medicine, London, UK
| | - Hae-Won Kim
- Institute of Tissue Regeneration Engineering (ITREN), Dankook University, Cheonan, Republic of Korea.,Department of Biomaterials Science, College of Dentistry, Dankook University, Cheonan, Republic of Korea.,UCL Eastman - Korea Dental Medicine Innovation Center, Dankook University, Cheonan, Republic of Korea.,Department of Nanobiomedical Science and BK21 PLUS NBM Global Research Center for Regenerative Medicine, Dankook University, Cheonan, Republic of Korea
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9
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Hydromechanical Structure of the Cochlea Supports the Backward Traveling Wave in the Cochlea In Vivo. Neural Plast 2018; 2018:7502648. [PMID: 30123255 PMCID: PMC6079393 DOI: 10.1155/2018/7502648] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Accepted: 05/12/2018] [Indexed: 11/17/2022] Open
Abstract
The discovery that an apparent forward-propagating otoacoustic emission (OAE) induced basilar membrane vibration has created a serious debate in the field of cochlear mechanics. The traditional theory predicts that OAE will propagate to the ear canal via a backward traveling wave on the basilar membrane, while the opponent theory proposed that the OAE will reach the ear canal via a compression wave. Although accepted by most people, the basic phenomenon of the backward traveling wave theory has not been experimentally demonstrated. In this study, for the first time, we showed the backward traveling wave by measuring the phase spectra of the basilar membrane vibration at multiple longitudinal locations of the basal turn of the cochlea. A local vibration source with a unique and precise location on the cochlear partition was created to avoid the ambiguity of the vibration source in most previous studies. We also measured the vibration pattern at different places of a mechanical cochlear model. A slow backward traveling wave pattern was demonstrated by the time-domain sequence of the measured data. In addition to the wave propagation study, a transmission line mathematical model was used to interpret why no tonotopicity was observed in the backward traveling wave.
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Ren T, He W, Barr-Gillespie PG. Reverse transduction measured in the living cochlea by low-coherence heterodyne interferometry. Nat Commun 2016; 7:10282. [PMID: 26732830 PMCID: PMC4729828 DOI: 10.1038/ncomms10282] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Accepted: 11/25/2015] [Indexed: 12/27/2022] Open
Abstract
It is generally believed that the remarkable sensitivity and frequency selectivity of mammalian hearing depend on outer hair cell-generated force, which amplifies sound-induced vibrations inside the cochlea. This 'reverse transduction' force production has never been demonstrated experimentally, however, in the living ear. Here by directly measuring microstructure vibrations inside the cochlear partition using a custom-built interferometer, we demonstrate that electrical stimulation can evoke both fast broadband and slow sharply tuned responses of the reticular lamina, but only a slow tuned response of the basilar membrane. Our results indicate that outer hair cells can generate sufficient force to drive the reticular lamina over all audible frequencies in living cochleae. Contrary to expectations, the cellular force causes a travelling wave rather than an immediate local vibration of the basilar membrane; this travelling wave vibrates in phase with the reticular lamina at the best frequency, and results in maximal vibration at the apical ends of outer hair cells.
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Affiliation(s)
- Tianying Ren
- Oregon Hearing Research Center, Department of Otolaryngology, Oregon Health & Science University, Portland, Oregon 97239, USA
| | - Wenxuan He
- Oregon Hearing Research Center, Department of Otolaryngology, Oregon Health & Science University, Portland, Oregon 97239, USA
| | - Peter G. Barr-Gillespie
- Oregon Hearing Research Center, Department of Otolaryngology, Oregon Health & Science University, Portland, Oregon 97239, USA
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Bell A, Wit HP. The vibrating reed frequency meter: digital investigation of an early cochlear model. PeerJ 2015; 3:e1333. [PMID: 26623180 PMCID: PMC4662588 DOI: 10.7717/peerj.1333] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Accepted: 09/28/2015] [Indexed: 01/11/2023] Open
Abstract
The vibrating reed frequency meter, originally employed by Békésy and later by Wilson as a cochlear model, uses a set of tuned reeds to represent the cochlea’s graded bank of resonant elements and an elastic band threaded between them to provide nearest-neighbour coupling. Here the system, constructed of 21 reeds progressively tuned from 45 to 55 Hz, is simulated numerically as an elastically coupled bank of passive harmonic oscillators driven simultaneously by an external sinusoidal force. To uncover more detail, simulations were extended to 201 oscillators covering the range 1–2 kHz. Calculations mirror the results reported by Wilson and show expected characteristics such as traveling waves, phase plateaus, and a response with a broad peak at a forcing frequency just above the natural frequency. The system also displays additional fine-grain features that resemble those which have only recently been recognised in the cochlea. Thus, detailed analysis brings to light a secondary peak beyond the main peak, a set of closely spaced low-amplitude ripples, rapid rotation of phase as the driving frequency is swept, frequency plateaus, clustering, and waxing and waning of impulse responses. Further investigation shows that each reed’s vibrations are strongly localised, with small energy flow along the chain. The distinctive set of equally spaced ripples is an inherent feature which is found to be largely independent of boundary conditions. Although the vibrating reed model is functionally different to the standard transmission line, its cochlea-like properties make it an intriguing local oscillator model whose relevance to cochlear mechanics needs further investigation.
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Affiliation(s)
- Andrew Bell
- John Curtin School of Medical Research, Australian National University , Canberra , Australia
| | - Hero P Wit
- Department of Otolaryngology/Head and Neck Surgery, University of Groningen , Groningen , The Netherlands
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12
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Abstract
Neuromorphic systems are used in variety of circumstances: as parts of sensory systems, for modeling parts of neural systems and for analog signal processing. In the sensory processing domain, neuromorphic systems can be considered in three parts: pre-transduction processing, transduction itself, and post-transduction processing. Neuromorphic systems include transducers for light, odors, and touch but so far neuromorphic applications in the sound domain have used standard microphones for transduction. We discuss why this is the case and describe what research has been done on neuromorphic approaches to transduction. We make a case for a change of direction toward systems where sound transduction itself has a neuromorphic component.
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Affiliation(s)
- Leslie S Smith
- Computing Science and Mathematics, University of Stirling Stirling, UK
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