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Hake AE, Kitsopoulos P, Grosh K. Design of Piezoelectric Dual-Bandwidth Accelerometers for Completely Implantable Auditory Prostheses. IEEE SENSORS JOURNAL 2023; 23:13957-13965. [PMID: 38766647 PMCID: PMC11101158 DOI: 10.1109/jsen.2023.3276271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
For the last 20 years, researchers have developed accelerometers to function as ossicular vibration sensors in order to eliminate the external components of hearing aid and cochlear implant systems. To date, no accelerometer has met all of the stringent performance requirements necessary to function in this capacity. In this work, we present an accelerometer design with an equivalent noise floor less than 20 phon equal-loudness-level over a 0.1-8 kHz bandwidth in a package small enough to be implanted in the middle ear. Our approach uses a dual-bandwidth (two sensing elements) microelectromechanical systems piezoelectric accelerometer, sized using an area-minimization process based on an experimentally-validated analytical model of the sensor. The resulting bandwidth of the low-frequency sensing element is 0.1-1.25 kHz and that of the high-frequency sensing element is 1.25-8 kHz. These sensing elements fit within a silicon frame that is 795 μm × 778 μm, which can reasonably be housed along with a required integrated circuit in a 2.2 mm × 2.7 mm × 1 mm package. The estimated total mass of the packaged system is approximately 14 mg. This dual-bandwidth MEMS sensor fills a technological gap in current completely implantable auditory prosthesis research and development by enabling a device capable of meeting physical and performance specifications needed for use in the middle ear.
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Affiliation(s)
- Alison E Hake
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI, 48109, USA, and is now with the Mechanical Engineering and Materials Science Department at the University of Pittsburgh, Pittsburgh, PA, 15260, USA
| | - Panagiota Kitsopoulos
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Karl Grosh
- Department of Mechanical Engineering and the Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, 48109, USA
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Hake AE, Zhao C, Sung WK, Grosh K. Design and Experimental Assessment of Low-Noise Piezoelectric Microelectromechanical Systems Vibration Sensors. IEEE SENSORS JOURNAL 2021; 21:17703-17711. [PMID: 35177956 PMCID: PMC8846575 DOI: 10.1109/jsen.2021.3085825] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The ubiquity of vibration sensors and accelerometers, as well as advances in microfabrication technologies, have led to the development of implantable devices for biomedical applications. This work describes a piezoelectric microelectromechanical systems accelerometer designed for potential use in auditory prostheses. The design includes an aluminum nitride bimorph beam with a silicon proof mass. Analytic models of the device sensitivity and noise are presented. These lead to a minimum detectable acceleration cost function for the sensor that can be used to optimize sensor designs more effectively than typical sensitivity maximizing or electrical noise minimizing approaches. A fabricated device with a 1 μm thick, 100 μm long, and 700 μm wide beam and a 400 μm thick, 63 μm long, and 740 μm wide proof mass is tested experimentally. Results indicate accurate modeling of the system sensitivity up to the first resonant frequency (1420 Hz). The low-frequency sensitivity of the device is 1.3 mV/g, and the input referred noise is 36.3 nV / Hz at 100 Hz and 11.8 nV / Hz at 1 kHz. The resulting minimum detectable acceleration at 100 Hz and 1 kHz is 28 μg / Hz and 9.1 μg / Hz , respectively. A brief explanation of the use of the validated cost function for sensor design is provided, as well as an example comparing the piezoelectric sensor design to another from the literature. It is concluded that a traditional single-resonance design cannot compete with the performance of acoustic sensors; therefore, novel device designs must be considered for implantable auditory prosthesis applications.
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Affiliation(s)
- Alison E Hake
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI 48109 USA
| | - Chuming Zhao
- University of Michigan, Ann Arbor, MI 48109 USA. He is now with Facebook Reality Lab, Redmond, WA 98052 USA
| | - Wang-Kyung Sung
- Vesper Technologies, Inc., Boston, MA 02110 USA. He is now with TDK-Invensense, San Jose, CA 95110 USA
| | - Karl Grosh
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI 48109 USA; Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109 USA
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3
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Calero D, Lobato L, Paul S, Cordioli JA. Analysis of the Human Middle Ear Dynamics Through Multibody Modeling. J Biomech Eng 2020; 142:1081896. [PMID: 32191261 DOI: 10.1115/1.4046689] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Indexed: 11/08/2022]
Abstract
The dynamics of the human middle ear (ME) has been studied in the past using several computational and experimental approaches in order to observe the effect on hearing of different conditions, such as conductive disease, corrective surgery, or implantation of a middle ear prosthesis. Multibody (MB) models combine the analysis of flexible structures with rigid body dynamics, involving fewer degrees-of-freedom (DOF) than finite element (FE) models, but a more detailed description than traditional 1D lumped parameter (LP) models. This study describes the reduction of a reference FE model of the human middle ear to a MB model and compares the results obtained considering different levels of model simplification. All models are compared by means of the frequency response of the stapes velocity versus sound pressure at the tympanic membrane (TM), as well as the system natural frequencies and mode shapes. It can be seen that the flexibility of the ossicles has a limited impact on the system frequency response function (FRF) and modes, and the stiffness of the tendons and ligaments only plays a role when above certain levels. On the other hand, the restriction of the stapes footplate movement to a piston-like behavior can considerably affect the vibrational modes, while constraints to the incudomalleolar joint (IMJ) and incudostapedial joint (ISJ) can have a strong impact on the system FRF.
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Affiliation(s)
- Diego Calero
- Acoustical and Vibration Laboratory, Department of Mechanical Engineering, Federal University of Santa Catarina, Florianópolis, SC 88040-900, Brazil
| | - Lucas Lobato
- Acoustical and Vibration Laboratory, Department of Mechanical Engineering, Federal University of Santa Catarina, Florianópolis, SC 88040-900, Brazil
| | - Stephan Paul
- Department of Mechanical Engineering, Acoustical and Vibration Laboratory, Federal University of Santa Catarina, Florianópolis, SC 88040-900, Brazil
| | - Júlio A Cordioli
- Acoustical and Vibration Laboratory, Department of Mechanical Engineering, Federal University of Santa Catarina, Florianópolis, SC 88040-900, Brazil
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Liu H, Zhang H, Yang J, Huang X, Liu W, Xue L. Influence of ossicular chain malformation on the performance of round-window stimulation: A finite element approach. Proc Inst Mech Eng H 2019; 233:584-594. [PMID: 30919729 DOI: 10.1177/0954411919839911] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
As a novel application of implantable middle ear hearing device, round-window stimulation is widely used to treat hearing loss with middle ear disease, such as ossicular chain malformation. To evaluate the influence of ossicular chain malformations on the efficiency of the round-window stimulation, a human ear finite element model, which incorporates cochlear asymmetric structure, was constructed. Five groups of comparison with experimental data confirmed the model’s validity. Based on this model, we investigated the influence of three categories of ossicular chain malformations, that is, incudostapedial disconnection, incus and malleus fixation, and fixation of the stapes. These malformations’ effects were evaluated by comparing the equivalent sound pressures derived from the basilar membrane displacement. Results show that the studied ossicular chain malformations mainly affected the round-window simulation’s performance at low frequencies. In contrast to the fixation of the ossicles, which mainly deteriorates round-window simulation’s low-frequency performance, incudostapedial disconnection increases this performance, especially in the absence of incus process and stapes superstructure. Among the studied ossicular chain malformations, the stapes fixation has a much more severe impact on the round-window stimulation’s efficiency. Thus, the influence of the patients’ ossicular chain malformations should be considered in the design of the round-window stimulation’s actuator. The low-frequency output of the round-window simulation’s actuator should be enhanced, especially for treating the patients with stapes fixation.
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Affiliation(s)
- Houguang Liu
- School of Mechatronic Engineering, China University of Mining and Technology, Xuzhou, P.R. China
| | - Hu Zhang
- School of Mechatronic Engineering, China University of Mining and Technology, Xuzhou, P.R. China
| | - Jianhua Yang
- School of Mechatronic Engineering, China University of Mining and Technology, Xuzhou, P.R. China
| | - Xinsheng Huang
- Department of Otorhinolaryngology-Head and Neck Surgery, Shanghai Zhongshan Hospital, Fudan University, Shanghai, P.R. China
| | - Wen Liu
- Department of Otolaryngology, Affiliated Hospital of Xuzhou Medical University, Xuzhou, P.R. China
| | - Lin Xue
- School of Mechatronic Engineering, China University of Mining and Technology, Xuzhou, P.R. China
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Calero D, Paul S, Gesing A, Alves F, Cordioli JA. A technical review and evaluation of implantable sensors for hearing devices. Biomed Eng Online 2018; 17:23. [PMID: 29433516 PMCID: PMC5810055 DOI: 10.1186/s12938-018-0454-z] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Accepted: 02/07/2018] [Indexed: 11/10/2022] Open
Abstract
Most commercially available cochlear implants and hearing aids use microphones as sensors for capturing the external sound field. These microphones are in general located in an external element, which is also responsible for processing the sound signal. However, the presence of the external element is the cause of several problems such as discomfort, impossibility of being used during physical activities and sleeping, and social stigma. These limitations have driven studies with the goal of developing totally implantable hearing devices, and the design of an implantable sensor has been one of the main challenges to be overcome. Different designs of implantable sensors can be found in the literature and in some commercial implantable hearing aids, including different transduction mechanisms (capacitive, piezoelectric, electromagnetic, etc), configurations microphones, accelerometers, force sensor, etc) and locations (subcutaneous or middle ear). In this work, a detailed technical review of such designs is presented and a general classification is proposed. The technical characteristics of each sensors are presented and discussed in view of the main requirements for an implantable sensor for hearing devices, including sensitivity, internal noise, frequency bandwidth and energy consumption. The feasibility of implantation of each sensor is also evaluated and compared.
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Affiliation(s)
- Diego Calero
- Laboratory of Vibration and Acoustics, Florianópolis, Brazil
| | - Stephan Paul
- Laboratory of Vibration and Acoustics, Florianópolis, Brazil
| | - André Gesing
- Laboratory of Vibration and Acoustics, Florianópolis, Brazil
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Tisch M. Implantable hearing devices. GMS CURRENT TOPICS IN OTORHINOLARYNGOLOGY, HEAD AND NECK SURGERY 2017; 16:Doc06. [PMID: 29279724 PMCID: PMC5738935 DOI: 10.3205/cto000145] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Combined hearing loss is an essential indication for implantable hearing systems. Depending on the bone conduction threshold, various options are available. Patients with mild sensorineural deafness usually benefit from transcutaneous bone conduction implants (BCI), while percutaneous BCI systems are recommended also for moderate hearing loss. For combined hearing losses with moderate and high-grade cochlear hearing loss, active middle ear implants are recommended. For patients with incompatibilities or middle ear surgery, implants are a valuable and proven addition to the therapeutic options.
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Affiliation(s)
- Matthias Tisch
- Department of Otolaryngology, Head & Neck Surgery, Bundeswehrkrankenhaus Ulm, Germany
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Liu H, Cheng J, Yang J, Rao Z, Cheng G, Yang S, Huang X, Wang M. Concept and Evaluation of a New Piezoelectric Transducer for an Implantable Middle Ear Hearing Device. SENSORS (BASEL, SWITZERLAND) 2017; 17:E2515. [PMID: 29099047 PMCID: PMC5713124 DOI: 10.3390/s17112515] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/17/2017] [Revised: 10/31/2017] [Accepted: 10/31/2017] [Indexed: 11/23/2022]
Abstract
Implantable middle ear hearing devices (IMEHDs) have been developed as a new technology to overcome the limitations of conventional hearing aids. The piezoelectric cantilever transducers currently used in the IMEHDs have the advantages of low power consumption and ease of fabrication, but generate less high-frequency output. To address this problem, we proposed and designed a new piezoelectric transducer based on a piezoelectric stack for the IMEHD. This new transducer, attached to the incus body with a coupling rod, stimulates the ossicular chain in response to the expansion-and-contraction of its piezoelectric stack. To test its feasibility for hearing loss compensation, a bench testing of the transducer prototype and a temporal bone experiment were conducted, respectively. Bench testing results showed that the new transducer did have a broad frequency bandwidth. Besides, the transducer was found to have a low total harmonic distortion (<0.75%) in all frequencies, and small release time (1 ms). The temporal bone experiment further proved that the transducer has the capability to produce sufficient vibrations to compensate for severe sensorineural hearing loss, especially at high frequencies. This property benefits the treatment of the most common sloping high-frequency sensorineural hearing loss. To produce a 100 dB SPL equivalent sound pressure at 1 kHz, its power consumption is 0.49 mW, which is low enough for the transducer to be utilized in the IMEHD.
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Affiliation(s)
- Houguang Liu
- School of Mechatronic Engineering, China University of Mining and Technology, Xuzhou 221116, China.
| | - Jinlei Cheng
- State Key Laboratory of Mechanical System and Vibrations, Shanghai Jiaotong University, Shanghai 200240, China.
| | - Jianhua Yang
- School of Mechatronic Engineering, China University of Mining and Technology, Xuzhou 221116, China.
| | - Zhushi Rao
- State Key Laboratory of Mechanical System and Vibrations, Shanghai Jiaotong University, Shanghai 200240, China.
| | - Gang Cheng
- School of Mechatronic Engineering, China University of Mining and Technology, Xuzhou 221116, China.
| | - Shanguo Yang
- School of Mechatronic Engineering, China University of Mining and Technology, Xuzhou 221116, China.
| | - Xinsheng Huang
- Department of Otorhinolaryngology, Zhongshan Hospital affiliated to Fudan University, Shanghai 200032, China.
| | - Mengli Wang
- School of Mechatronic Engineering, China University of Mining and Technology, Xuzhou 221116, China.
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Ulusoy S, Muluk NB, San T, Cingi C. Evaluation of patient satisfaction with different hearing aids: A study of 107 patients. EAR, NOSE & THROAT JOURNAL 2017; 96:E22-E28. [PMID: 28122108 DOI: 10.1177/014556131709600103] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
We retrospectively investigated patient satisfaction with different types of hearing aids in 107 patients-60 males and 47 females, aged 8 to 84 years (mean: 53.8)-with unilateral or bilateral hearing loss, each of whom used two different hearing devices for at least 3 years per device. The International Outcome Inventory for Hearing Aids, Turkish edition (IOI-HA-TR) was used to evaluate satisfaction levels; we also calculated our own total individual subjective satisfaction (TISS) scores. We divided 16 different hearing devices into two types: device 1 and device 2; on average, device 2 had more channels, a lower minimum frequency, and a higher maximum frequency. We found that the IOI-HA-TR scores and TISS scores were higher and usage time was greater during device 2 use, and that there was a positive correlation between IOI-HA-TR and TISS scores. A total of 69 patients (64.5%) used device 2 for more than 8 hours per day, while 38 patients (35.5%) used it for 4 to 8 hours per day during the final 2 weeks of the trial. In contrast, 40 patients (37.4%) used device 1 for more than 8 hours, 50 (46.7%) used it for 4 to 8 hours, and the remaining 17 (15.9%) used it for less than 4 hours; the difference in the duration of use of the two devices was statistically significant (p < 0.001). Younger patients and patients with more education were more satisfied with their devices than were older patients and those who were not as well educated. We conclude that devices with good technologic features such as more channels, a lower minimum frequency, and a higher maximum frequency result in better hearing. Also, based on the age difference that we observed, we recommend that psychological support be provided to older patients with aided hearing to enhance their mental health and quality of life.
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Monini S, Bianchi A, Talamonti R, Atturo F, Filippi C, Barbara M. Patient satisfaction after auditory implant surgery: ten-year experience from a single implanting unit center. Acta Otolaryngol 2017; 137:389-397. [PMID: 27918233 DOI: 10.1080/00016489.2016.1258733] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
CONCLUSIONS The satisfaction rate of the subjects with an auditory implant appears strictly related to the resulting auditory improvement, and the surgical variables would play a prevailing role in respect to the esthetic factors. OBJECTIVES To assess the rate of satisfaction in subjects who underwent the surgical application of an auditory device at a single Implanting Center Unit. METHOD A series of validated questionnaires has been administered to subjects who underwent the surgical application of different auditory devices. The Glasgow Benefit Inventory (GBI), the Visual Analog Scale (VAS), and the Abbreviated Profile of Hearing Aid Benefit (APHAB) have been used to compare the implanted situation with the hearing-aided one; a percutaneous bone conductive implant (pBCI) with an active middle ear implant (AMEI) on the round window in mixed hearing loss; and an invisible, fully-implantable device with a frankly and bulky semi-implantable device. RESULTS The mean GBI scores were higher in Vibrant Soundbridge (VSB)® and Bonebridge® subjects, without significant differences among the various devices. The mean VAS score increased for all the devices in comparison with the conventional hearing aid. The mean APHAB score was similarly better in the implanted condition as total and partial scores.
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Affiliation(s)
- Simonetta Monini
- NESMOS Department, ENT Clinic, Medicine and Psychology, Sapienza University, Rome, Italy
| | - Alessandra Bianchi
- NESMOS Department, ENT Clinic, Medicine and Psychology, Sapienza University, Rome, Italy
| | - Rita Talamonti
- NESMOS Department, ENT Clinic, Medicine and Psychology, Sapienza University, Rome, Italy
| | - Francesca Atturo
- NESMOS Department, ENT Clinic, Medicine and Psychology, Sapienza University, Rome, Italy
| | - Chiara Filippi
- NESMOS Department, ENT Clinic, Medicine and Psychology, Sapienza University, Rome, Italy
| | - Maurizio Barbara
- NESMOS Department, ENT Clinic, Medicine and Psychology, Sapienza University, Rome, Italy
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Xu D, Liu H, Zhou L, Cheng G, Yang J, Huang X, Liu X. The effect of actuator and its coupling conditions on eardrum-stimulated middle ear implants: A numerical analysis. Proc Inst Mech Eng H 2016. [DOI: 10.1177/0954411916675381] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Consisting of the actuator and coupling layer, a finite element model of the human middle ear was used to analyze the effect of the actuator and its coupling conditions on the performance of the eardrum-stimulated middle ear implants. This model which was based on the right ear of a healthy adult was built via microcomputed tomography imaging and the technique of reverse engineering. Based on this finite element model, the linear viscoelasticity of the human middle ear soft tissues and three-layer structure of the eardrum pars tensa which was orthotropic were considered. The validity of the model was verified by comparing the model calculated results with experimental data. After that, the influence of the three main design parameters of the actuator and two aspects of the coupling layer were investigated by the finite element model. The results show that (1) the manubrium tip is the optimal position for the actuator to stimulate; (2) the increased cross-section of the actuator would worsen its hearing compensation performance, especially in the low frequencies; (3) both the patients’ residual hearing and the actuator’s hearing compensation performance at high frequencies will be deteriorated with the increase in the actuator’s mass; and (4) a coupling layer with a small Young’s modulus and an area approximating 80% of the eardrum would reduce the stress of the eardrum effectively.
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Affiliation(s)
- Dan Xu
- School of Mechatronic Engineering, China University of Mining and Technology, Xuzhou, P.R. China
| | - Houguang Liu
- School of Mechatronic Engineering, China University of Mining and Technology, Xuzhou, P.R. China
| | - Lei Zhou
- Department of Otorhinolaryngology-Head and Neck Surgery, Shanghai Zhongshan Hospital, Fudan University, Shanghai, P.R. China
| | - Gang Cheng
- School of Mechatronic Engineering, China University of Mining and Technology, Xuzhou, P.R. China
| | - Jianhua Yang
- School of Mechatronic Engineering, China University of Mining and Technology, Xuzhou, P.R. China
| | - Xinsheng Huang
- Department of Otorhinolaryngology-Head and Neck Surgery, Shanghai Zhongshan Hospital, Fudan University, Shanghai, P.R. China
| | - Xiaole Liu
- School of Mechatronic Engineering, China University of Mining and Technology, Xuzhou, P.R. China
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11
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Djalilian HR, Mahboubi H, Haidar YM, Paulick P, Merlo MW, Bachman M. Development of a novel completely-in-the-canal direct-drive hearing device. Laryngoscope 2016; 127:932-938. [PMID: 27546727 DOI: 10.1002/lary.26221] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Accepted: 07/05/2016] [Indexed: 11/08/2022]
Abstract
OBJECTIVES/HYPOTHESIS To develop a novel completely-in-the-canal device capable of directly driving the tympanic membrane (TM) and ossicular chain from the ear canal. STUDY DESIGN Development and feasibility study. METHODS A voice coil actuator design was developed to drive the TM. Bench testing of the device using laser Doppler vibrometry (LDV) and sound recording was performed. Temporal bone studies using LDV were performed using different designs of the contact tip-TM interface to find the most efficient method of sound transmission. Two short-term clinical performance studies were performed using the latest 3-mm-wide device. Comparison was made to natural sound and to the Vibrant SoundBridge floating mass transducer simulator. RESULTS On bench testing, the device was found to have a low (<0.5%) total harmonic distortion in all frequencies above 400 Hz. Temporal bone studies revealed the device was capable of producing vibrations equivalent to 104 to 120 dB sound across most frequencies. The most efficient method of stimulation was when the device was coupled to the malleus. Short-term clinical performance studies indicated that pure tones and complex sound can be presented with the device. The sound quality of the experimental device was rated as better than the SoundBridge simulator device. CONCLUSIONS The direct-drive hearing device is capable of producing a wide range of sound frequencies and amplitudes. The device can transmit complex sound with low power requirements. Further work on the development of the device is needed for long-term and wider clinical use. LEVEL OF EVIDENCE NA Laryngoscope, 127:932-938, 2017.
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Affiliation(s)
- Hamid R Djalilian
- Division of Neurotology and Skull Base Surgery, Department of Otolaryngology-Head and Neck Surgery, University of California, Irvine, Irvine, California, U.S.A.,Department of Biomedical Engineering, University of California, Irvine, Irvine, California, U.S.A
| | - Hossein Mahboubi
- Division of Neurotology and Skull Base Surgery, Department of Otolaryngology-Head and Neck Surgery, University of California, Irvine, Irvine, California, U.S.A
| | - Yarah M Haidar
- Division of Neurotology and Skull Base Surgery, Department of Otolaryngology-Head and Neck Surgery, University of California, Irvine, Irvine, California, U.S.A
| | - Peyton Paulick
- Department of Biomedical Engineering, University of California, Irvine, Irvine, California, U.S.A
| | - Mark W Merlo
- Department of Biomedical Engineering, University of California, Irvine, Irvine, California, U.S.A
| | - Mark Bachman
- Department of Computer Science and Electrical Engineering, University of California, Irvine, Irvine, California, U.S.A
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12
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LIU HOUGUANG, GE SHIRONG, CHENG GANG, YANG JIANHUA, RAO ZHUSHI, HUANG XINSHENG. THE EFFECT OF IMPLANTABLE TRANSDUCERS ON MIDDLE EAR TRANSFER FUNCTION — A COMPARATIVE NUMERICAL ANALYSIS. J MECH MED BIOL 2016. [DOI: 10.1142/s0219519416500408] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Several types of middle ear implants (MEIs) have been invented as an alternative to conventional hearing aids for the rehabilitation of sensorineural hearing loss. Temporal bone and clinical studies have shown that the implantation of MEIs’ transducers influences middle ear transfer function. But there is little comparative data available about these influences. We conducted comparative studies on the influences of three principal types of MEI transducers in respect to their attachment points on the ossicular chain. To aid the investigation, a human middle ear finite element model was constructed. The model was built based on a complete set of micro-computerized tomography section images of a human ear by reverse engineering technology. The validity of the developed model was verified by comparing the motions obtained by this model with published experimental measurements on human temporal bones. The results show that the eardrum driving transducer (EDT) and the floating mass transducer (FMT) decrease stapes displacement prominently at high frequencies. The greater these transducers’ mass, the smaller is the displacement of the stapes footplate. In contrast, the incus body driving transducer (IBDT) decreases stapes displacement severely at low frequencies, and its adverse effect on residual hearing increases with increasing stiffness of the IBDT’s driving rod.
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Affiliation(s)
- HOUGUANG LIU
- School of Mechatronic Engineering, China University of Mining and Technology, Da Xue Road No. 1, Xuzhou 221116, P. R. China
| | - SHIRONG GE
- School of Mechatronic Engineering, China University of Mining and Technology, Da Xue Road No. 1, Xuzhou 221116, P. R. China
| | - GANG CHENG
- School of Mechatronic Engineering, China University of Mining and Technology, Da Xue Road No. 1, Xuzhou 221116, P. R. China
| | - JIANHUA YANG
- School of Mechatronic Engineering, China University of Mining and Technology, Da Xue Road No. 1, Xuzhou 221116, P. R. China
| | - ZHUSHI RAO
- State Key Laboratory of Mechanical System and Vibration, Shanghai Jiao Tong University, Dong Chuan Road No. 800, Shanghai 200240, P. R. China
| | - XINSHENG HUANG
- Department of Otorhinolaryngology-Head and Neck Surgery, Zhongshan Hospital, Fudan University, Feng Lin Road No. 180, Shanghai 200032, P. R. China
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Woo ST, Shin DH, Lim HG, Seong KW, Gottlieb P, Puria S, Lee KY, Cho JH. A New Trans-Tympanic Microphone Approach for Fully Implantable Hearing Devices. SENSORS 2015; 15:22798-810. [PMID: 26371007 PMCID: PMC4610505 DOI: 10.3390/s150922798] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Revised: 08/28/2015] [Accepted: 08/31/2015] [Indexed: 11/16/2022]
Abstract
Fully implantable hearing devices (FIHDs) have been developed as a new technology to overcome the disadvantages of conventional acoustic hearing aids. The implantable microphones currently used in FIHDs, however, have difficulty achieving high sensitivity to environmental sounds, low sensitivity to body noise, and ease of implantation. In general, implantable microphones may be placed under the skin in the temporal bone region of the skull. In this situation, body noise picked up during mastication and touching can be significant, and the layer of skin and hair can both attenuate and distort sounds. The new approach presently proposed is a microphone implanted at the tympanic membrane. This method increases the microphone’s sensitivity by utilizing the pinna’s directionally dependent sound collection capabilities and the natural resonances of the ear canal. The sensitivity and insertion loss of this microphone were measured in human cadaveric specimens in the 0.1 to 16 kHz frequency range. In addition, the maximum stable gain due to feedback between the trans-tympanic microphone and a round-window-drive transducer, was measured. The results confirmed in situ high-performance capabilities of the proposed trans-tympanic microphone.
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Affiliation(s)
- Seong Tak Woo
- Graduate School of Electronic Engineering, Kyungpook National University, 80 Daehak-ro, Buk-gu, 41566 Daegu, Korea.
| | - Dong Ho Shin
- Graduate School of Electronic Engineering, Kyungpook National University, 80 Daehak-ro, Buk-gu, 41566 Daegu, Korea.
| | - Hyung-Gyu Lim
- Graduate School of Electronic Engineering, Kyungpook National University, 80 Daehak-ro, Buk-gu, 41566 Daegu, Korea.
| | - Ki-Woong Seong
- Department of Biomedical Engineering, Kyungpook National University Hospital, 130 Dongdeok-ro, Jung-gu, 41944 Daegu, Korea.
| | - Peter Gottlieb
- Department of Mechanical Engineering, Stanford University, 496 Lomita Mall, 94305 CA, USA.
| | - Sunil Puria
- Department of Mechanical Engineering, Stanford University, 496 Lomita Mall, 94305 CA, USA.
| | - Kyu-Yup Lee
- Department of Otorhinolaryngology-Head and Neck Surgery, School of Medicine, Kyungpook National University, 680 Gukchaebosang-ro, Jung-gu, 41944 Daegu, Korea.
| | - Jin-Ho Cho
- Graduate School of Electronic Engineering, Kyungpook National University, 80 Daehak-ro, Buk-gu, 41566 Daegu, Korea.
- School of Electronics Engineering, College of IT Engineering, Kyungpook National University, 80 Daehakro, Buk-gu, 41566 Daegu, Korea.
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14
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Paulick PE, Merlo MW, Mahboubi H, Djalilian HR, Bachman M. A micro-drive hearing aid: a novel non-invasive hearing prosthesis actuator. Biomed Microdevices 2015; 16:915-25. [PMID: 25129112 DOI: 10.1007/s10544-014-9896-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The direct hearing device (DHD) is a new auditory prosthesis that combines conventional hearing aid and middle ear implant technologies into a single device. The DHD is located deep in the ear canal and recreates sounds with mechanical movements of the tympanic membrane. A critical component of the DHD is the microactuator, which must be capable of moving the tympanic membrane at frequencies and magnitudes appropriate for normal hearing, with little distortion. The DHD actuator reported here utilized a voice coil actuator design and was 3.7 mm in diameter. The device has a smoothly varying frequency response and produces a precisely controllable force. The total harmonic distortion between 425 Hz and 10 kHz is below 0.5 % and acoustic noise generation is minimal. The device was tested as a tympanic membrane driver on cadaveric temporal bones where the device was coupled to the umbo of the tympanic membrane. The DHD successfully recreated ossicular chain movements across the frequencies of human hearing while demonstrating controllable magnitude. Moreover, the micro-actuator was validated in a short-term human clinical performance study where sound matching and complex audio waveforms were evaluated by a healthy subject.
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15
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Oliveira FPM, Faria DB, Tavares JMRS. Automated segmentation of the incus and malleus ossicles in conventional tri-dimensional computed tomography images. Proc Inst Mech Eng H 2014; 228:810-8. [PMID: 25085697 DOI: 10.1177/0954411914546123] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
This article proposes a fully automated computational solution to segment the incus and malleus ear ossicles in conventional tri-dimensional X-ray computed tomography images. The solution uses a registration-based segmentation paradigm, followed by image segmentation refinement. It was tested against a dataset comprising 21 computed tomography volumetric images of the ear acquired using standard protocols and with resolutions varying from 0.162 × 0.162 × 0.6 to 0.166 × 0.166 × 1.0 mm(3). The images used were randomly selected from subjects who had had a computed tomography examination of the ear due to ear-related pathologies. Dice's coefficient and the Hausdorff distance were used to compare the results of the automated segmentation against those of a manual segmentation performed by two experts. The mean agreement between automated and manual segmentations was equal to 0.956 (Dice's coefficient), and the mean Hausdorff distance among the shapes obtained was 1.14 mm, which is approximately equal to the maximum distance between the neighbouring voxels in the dataset tested. The results confirm that the automated segmentation of the incus and malleus ossicles in tri-dimensional images acquired from patients with ear-related pathologies, using conventional computed tomography scanners and standard protocols, is feasible, robust and accurate. Thus, the solution developed can be employed efficiently in computed tomography ear examinations to help radiologists and otolaryngologists in the evaluation of bi-dimensional slices by providing the related tri-dimensional model.
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Affiliation(s)
- Francisco P M Oliveira
- Institute of Nuclear Sciences Applied to Health (ICNAS) and Institute for Biomedical Imaging and Life Sciences (IBILI), Faculty of Medicine, University of Coimbra, Coimbra, Portugal
| | - Diogo Borges Faria
- HPP Medicina Molecular, SA., Faculdade de Engenharia, Universidade do Porto, Porto, Portugal
| | - João Manuel R S Tavares
- Instituto de Engenharia Mecânica e Gestão Industrial, Departamento de Engenharia Mecânica, Faculdade de Engenharia, Universidade do Porto, Porto, Portugal
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16
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An incus-body driving type piezoelectric middle ear implant design and evaluation in 3D computational model and temporal bone. ScientificWorldJournal 2014; 2014:121624. [PMID: 25045723 PMCID: PMC4086470 DOI: 10.1155/2014/121624] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2014] [Revised: 05/21/2014] [Accepted: 05/26/2014] [Indexed: 11/17/2022] Open
Abstract
A new incus-body driving type transducer relying on piezoelectric stack, with broad frequency bandwidth, is proposed for use in a middle ear implant. To aid the design process of this transducer, a coupling biomechanical model of the human middle ear and the piezoelectric transducer was established by reverse engineering technology. The validity of this model was confirmed by comparing model predicted motions with experimental measurements. Based on this verified biomechanical model, the main parameters of the transducer were determined. And its power consumption was calculated. Finally, to verify the capability of the designed piezoelectric transducer, a human temporal bone experimental platform was built. And the dynamic characteristics and the stimulated performance of the piezoelectric transducer were tested. The result showed that stapes displacement stimulated by the transducer excitation at 10.5 V RMS was equivalent to that from acoustic stimulation at 100 dB SPL, which is an adequate stimulation to the ossicular chain. The corresponding power consumption is 0.31 mW per volt of excitation at 1 kHz, which is low enough for the transducer to be used in a middle ear implant. Besides, this transducer demonstrates high performance at high frequencies.
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17
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Efficacy of the active middle-ear implant in patients with sensorineural hearing loss. The Journal of Laryngology & Otology 2013; 127 Suppl 2:S8-16. [DOI: 10.1017/s0022215113001151] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
AbstractIntroduction:This systematic review aims to advise on the effectiveness of the active middle-ear implant in patients with sensorineural hearing loss, compared with external hearing aids.Methods:A systematic search of several electronic databases, including PubMed and Embase, was used to identify relevant studies for inclusion.Results:Fourteen comparative studies were included. Nine studies reported on the primary outcome of functional gain: one found that the middle-ear implant was significantly better than external hearing aids (p < 0.001), while another found that external hearing aids were generally significantly better than middle-ear implants (p < 0.05). Six of the seven remaining studies found that middle-ear implants were better than external hearing aids, although generally no clinically significant difference (i.e. ≥10 dB) was seen.Conclusion:Generally, the active middle-ear implant appears to be as effective as the external hearing aid in improving hearing outcomes in patients with sensorineural hearing loss.
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18
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Vibrant sound bridge application to middle ear windows versus conventional hearing aids: a comparative study based on international outcome inventory for hearing aids. Eur Arch Otorhinolaryngol 2013; 271:35-40. [DOI: 10.1007/s00405-013-2387-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2012] [Accepted: 01/28/2013] [Indexed: 10/27/2022]
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19
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Investigation of a novel completely-in-the-canal direct-drive hearing device: a temporal bone study. Otol Neurotol 2012. [PMID: 23202151 DOI: 10.1097/mao.0b013e318278522e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
HYPOTHESIS Whether a prototype direct-drive hearing device (DHD) is effective in driving the tympanic membrane (TM) in a temporal bone specimen to enable it to potentially treat moderate-to-severe hearing loss. BACKGROUND Patient satisfaction with air conduction hearing aids has been low because of sound distortion, occlusion effect, and feedback issues. Implantable hearing aids provide a higher quality sound but require surgery for placement. The DHD was designed to combine the ability of driving the ossicular chain with placement in the external auditory canal. METHODS DHD is a 3.5-mm wide device that could fit entirely into the bony ear canal and directly drive the TM rather than use a speaker. A cadaveric temporal bone was prepared. The device developed in our laboratory was coupled to the external surface of the TM and against the malleus. Frequency sweeps between 300 Hz to 12 kHz were performed in 2 different coupling methods at 104 and 120 dB, and the DHD was driven with various levels of current. Displacements of the posterior crus of the stapes were measured using a laser Doppler vibrometer. RESULTS The DHD showed a linear frequency response from 300 Hz to 12 kHz. Placement against the malleus showed higher amplitudes and lower power requirements than when the device was placed on the TM. CONCLUSION DHD is a small completely-in-the-canal device that mechanically drives the TM. This novel device has a frequency output wider than most air conduction devices. Findings of the current study demonstrated that the DHD had the potential of being incorporated into a hearing aid in the future.
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20
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Abstract
Strictly speaking, implantable hearing aids are technical systems that process audiological signals and convey these by direct mechanical stimulation of the ossicular chain or cochlea. They have certain benefits over conventional hearing aids in terms of wearing comfort and general acceptance. As current studies lack convincing audiological results, the indications for implantable hearing aids are primarily of medical or cosmetic nature. To date, three systems are available in Germany: Vibrant Soundbridge®, Carina®, and Esteem®. Because the performance of the different implantable and nonimplantable hearing systems together with various surgical procedures are currently undergoing major changes, audiological indications may also develop in the future.
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Affiliation(s)
- J C Luers
- HNO-Klinik, Universitätsklinik Köln, 50924, Köln, Deutschland.
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21
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Wang X, Hu Y, Wang Z, Shi H. Finite element analysis of the coupling between ossicular chain and mass loading for evaluation of implantable hearing device. Hear Res 2011; 280:48-57. [PMID: 21554941 DOI: 10.1016/j.heares.2011.04.012] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/08/2010] [Revised: 04/11/2011] [Accepted: 04/14/2011] [Indexed: 11/15/2022]
Abstract
Finite element (FE) model is used to analyze the coupling effects between ossicular chain and transducer of implantable middle-ear hearing devices. The mass loading of the transducer is attached to the long process of the incus in the form of floating mass transducer (FMT) or applied near the incus-stapes joint by a magnet of contactless electromagnetic transducer (CLT). By changing placement of the transducer, crimping connection and damping parameter of the crimping mechanism, theoretical performances of the transducers were investigated on mechanical characteristics in two aspects: (1) displacement change at the stapes footplate, which describes the change in hearing due to placement of the transducer; (2) the equivalent pressure output of the transducer, which relates the footplate displacement driven by transducer to the sound pressure applied to a normal ear to produce that displacement. For the FMT with a less tight crimping connection or low supporting rigidity, a large drop of the sound-induced stapes displacement occurs at a specific frequency, with a peak reduction about 25.8 dB. A tight connection or high supporting rigidity shifts the drop of the stapes displacement to higher frequency. For the CLT, an electromagnetic transducer of 25 mg placed near the incus-stapes joint produces a maximum decrease of the stapes displacement around 16.5 dB. The equivalent sound pressure output and electromagnetic force requirement are proposed to produce the stapes displacement equivalent to that ear canal sound stimulus. The drop of the footplate displacement caused by mass loading effect can be recovered by the transducer stimulation over frequency range from 1500 Hz to 4000 Hz. The FE analysis reveals that enhancing the coupling stiffness between the clip and the ossicular chain is much helpful for maximizing the efficiency of the transducer stimulation.
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Affiliation(s)
- Xuelin Wang
- School of Mechanical Science and Engineering, Huazhong University of Science and Technology, No. 1037, Luoyu Road, Wuhan, Hubei 430074, China.
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22
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Gan RZ, Dai C, Wang X, Nakmali D, Wood MW. A totally implantable hearing system--design and function characterization in 3D computational model and temporal bones. Hear Res 2009; 263:138-44. [PMID: 19772909 DOI: 10.1016/j.heares.2009.09.003] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2009] [Revised: 09/11/2009] [Accepted: 09/17/2009] [Indexed: 11/25/2022]
Abstract
Implantable middle ear hearing devices are emerging as an effective technology for patients with mild to moderately severe sensorineural hearing loss. Several devices with electromagnetic or piezoelectric transducers have been investigated or developed in the US and Europe since 1990. This paper reports a totally implantable hearing system (TIHS) currently under investigation in Oklahoma. The TIHS consists of implant transducer (magnet), implantable coil and microphone, DSP-audio signal processor, rechargeable battery, and remote control unit. The design of TIHS is based on a 3D finite element model of the human ear and the analysis of electromagnetic coupling of the transducer. Function of the TIHS is characterized over the auditory frequency range in three aspects: (1) mass loading effect on residual hearing with a passive implant, (2) efficiency of electromagnetic coupling between the implanted coil and magnet, and (3) functional gain of whole unit in response to acoustic input across the human skin. This paper focuses on mass loading effect and the efficiency of electromagnetic coupling of TIHS determined from the FE model of the human ear and the cadaver ears or temporal bones. Some preliminary data of whole unit function are also presented in the paper.
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Affiliation(s)
- Rong Z Gan
- University of Oklahoma, Norman, OK 73019, USA.
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23
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Kositsky M, Chiappalone M, Alford ST, Mussa-Ivaldi FA. Brain-machine interactions for assessing the dynamics of neural systems. Front Neurorobot 2009; 3:1. [PMID: 19430593 PMCID: PMC2679156 DOI: 10.3389/neuro.12.001.2009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2008] [Accepted: 02/08/2009] [Indexed: 11/14/2022] Open
Abstract
A critical advance for brain–machine interfaces is the establishment of bi-directional communications between the nervous system and external devices. However, the signals generated by a population of neurons are expected to depend in a complex way upon poorly understood neural dynamics. We report a new technique for the identification of the dynamics of a neural population engaged in a bi-directional interaction with an external device. We placed in vitro preparations from the lamprey brainstem in a closed-loop interaction with simulated dynamical devices having different numbers of degrees of freedom. We used the observed behaviors of this composite system to assess how many independent parameters − or state variables − determine at each instant the output of the neural system. This information, known as the dynamical dimension of a system, allows predicting future behaviors based on the present state and the future inputs. A relevant novelty in this approach is the possibility to assess a computational property – the dynamical dimension of a neuronal population – through a simple experimental technique based on the bi-directional interaction with simulated dynamical devices. We present a set of results that demonstrate the possibility of obtaining stable and reliable measures of the dynamical dimension of a neural preparation.
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Affiliation(s)
- Michael Kositsky
- Department of Physiology, Northwestern University Chicago, IL, USA
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