WO1999031937A1 - Automatic system for optimizing hearing aid adjustments - Google Patents

Automatic system for optimizing hearing aid adjustments Download PDF

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Publication number
WO1999031937A1
WO1999031937A1 PCT/US1998/025950 US9825950W WO9931937A1 WO 1999031937 A1 WO1999031937 A1 WO 1999031937A1 US 9825950 W US9825950 W US 9825950W WO 9931937 A1 WO9931937 A1 WO 9931937A1
Authority
WO
WIPO (PCT)
Prior art keywords
words
hearing aid
speech material
aid
hearing
Prior art date
Application number
PCT/US1998/025950
Other languages
French (fr)
Inventor
Reginald G. Garratt
Original Assignee
Knowles Electronics, Inc.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Knowles Electronics, Inc. filed Critical Knowles Electronics, Inc.
Priority to AU16307/99A priority Critical patent/AU1630799A/en
Publication of WO1999031937A1 publication Critical patent/WO1999031937A1/en

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Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R25/00—Deaf-aid sets, i.e. electro-acoustic or electro-mechanical hearing aids; Electric tinnitus maskers providing an auditory perception
    • H04R25/70—Adaptation of deaf aid to hearing loss, e.g. initial electronic fitting

Definitions

  • the present application relates to hearing aids having adjustable frequency response characteristics, and more particularly, to a system which optimizes the frequency response characteristics of a hearing aid for a particular user.
  • the hearing threshold of an individual is measured by one skilled in the art, typically an audiologist, using a variety of sounds, including pure tones and warble tones, and an audiometer. The result is displayed in an audiogram to show the difference in the hearing threshold for the individual and that of a normal hearing listener at 6 to 8 audio frequencies provided by the audiometer. Additional information is collected to characterize the sensitivity of the individual to loud sounds. This combined information is a measure of the individual's dynamic range of hearing. Various protocols or formulas (such as the Half Gain rule, NAL, and POGO) have been used to define the desired hearing aid performance that would best serve the impaired individual. The hearing aid(s) that most closely matches the desired performance are then selected by the dispenser. In the fitting step, the dispenser fine tunes the adjustable features in the hearing aid to achieve the best match to the desired performance.
  • the dispenser fine tunes the adjustable features in the hearing aid to achieve the best match to the desired performance.
  • the prior art hearing aid fitting adjustment procedure can be quite long and tedious, and its accuracy is limited because it is only guided by the fitting protocols and the experience/training of the dispenser to interpret the results of the work list test. While hearing loss has some typical patterns addressed by the fitting protocols, hearing loss is a highly specific condition that varies greatly from one individual to another such that the fitting protocols are not very accurate. As hearing aid technology has advanced with programmable and digital hearing aids, the range and number of parameters that can be electronically adjusted have increased. Fitting protocols have not developed as rapidly as hearing aid technology, and the fitting time has increased significantly, leading to sub- optimized performance. Summary Of The Invention
  • the present invention is directed to a computer system method an apparatus for optimizing and automating the fitting of hearing aids based on speech material (not tones) as the input source to measure the performance of the individual using the aid.
  • Figure 1 illustrate a flow diagram of the overall fitting process of the present invention
  • Figure 1 A illustrates a more detailed flow diagram for the determination of an imputed inverse transform, as used in the fitting process of Figure 1 ;
  • Figure IB illustrates a more detailed flow diagram of the optimization process as used in the fitting process of Figure 1 ;
  • Figure 2 illustrates a hearing impaired individual training the speech recognition engine (SRE) to learn to recognize words dictated by the individual as read from the SRE computer monitor;
  • SRE speech recognition engine
  • Figure 3 illustrates the hearing impaired individual with relevant hardware arrangement
  • Figure 4 illustrates a count of words in an error list as the optimization process proceeds.
  • the overall fitting process begins by having a hearing impaired subject train a voice/speech recognition engine (SRE) computer to recognize words as read from a visual presentation by the SRE on a computer monitor training screen. Subsequently, the dispenser fits a programmable hearing aid on the hearing impaired subject and connects the hearing aid to the program adjust module, such as Arthur, which is also resident in the computer.
  • SRE voice/speech recognition engine
  • a computer system 10 for optimizing and automating the fitting of hearing aids based on speech material (not tones) as an input source to measure performance of a hearing impaired individual using the hearing aid is illustrated in Figure 3.
  • the computer system includes, as resident software, an SRE module, a Arthur module, an imputed inverse transform module and an optimization module.
  • speech material consisting of nonsense sentences or un-related words from a word list that are very rich in frequency content and replete with time and amplitude variations is stored in the memory of the computer system 10.
  • the stored speech material is presented aurally by the computer system 10 by means of a speaker 12 to the hearing impaired individual wearing an electronically adjustable hearing aid 14.
  • the hearing aid 14 is connected to the computer system 10 by a cable, or some form of wireless data transfer.
  • the individual identifies the words that are heard by repeating them back into the computer system 10 via a microphone 16 (Fig. 2), which then compares this input to original speech material and lists the incorrect words in an error file in the computer system 10.
  • the computer system 10 calculates an imputed inverse transform for a digital (DSP) aid and guides the adjustable parameters within the imputed inverse transform in a programmable DSP aid in an optimization routine to reduce the error list to a minimum through repeated trials.
  • the computer system 10 can also adjust the parameters in a fixed program DSP aid or an analog aid in an optimization routine to reduce the error list to a minimum through repeated trials.
  • the fitting Since the optimization routine is based on mathematical concepts, such as the Simplex algorithm or those used in multi-dimensional servo control systems, the fitting is highly time efficient, accurate and independent of the experience of the dispenser. A further benefit is that the fitting is completely automatic, leading to lower hearing aid distribution cost.
  • the hearing impaired subject repeats the speech material into the microphone 16 connected to the SRE module, a voice/speech recognition engine that is a part of the computer system 10.
  • Keyboard entry or touch screens might also be used to enter the subject's repeated speech material into the computer system 10, but many subjects are not skilled with this form of data entry.
  • Another party, such as the dispenser could enter data, but this would not be automated and would not lower the cost of dispensing.

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  • Health & Medical Sciences (AREA)
  • General Health & Medical Sciences (AREA)
  • Neurosurgery (AREA)
  • Otolaryngology (AREA)
  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Signal Processing (AREA)
  • Electrically Operated Instructional Devices (AREA)

Abstract

A system for optimizing hearing aid adjustments is disclosed. The system includes a computer (10). Speech material consisting of nonsense sentences or unrelated words from a word list is provided (12). The words are rich in frequency content and replete with time and amplitude variations. The speech material is presented aurally by a computer system (10) to a hearing impaired individual wearing an electronically adjustable hearing aid (14). The individual repeats the words, and the computer system (10) compares the repeated words to the original speech material and identifies the incorrect words in an error file. The system considers the incorrectly identified words and uses pre-knowledge of their frequency content and their time and amplitude variations to calculate an imputed inverse transform for a digital (DSP) aid.

Description

AUTOMATIC SYSTEM FOR OPTIMIZING HEARING AID ADJUSTMENTS
DESCRIPTION
Technical Field
The present application relates to hearing aids having adjustable frequency response characteristics, and more particularly, to a system which optimizes the frequency response characteristics of a hearing aid for a particular user.
Background Of The Invention
The hearing threshold of an individual is measured by one skilled in the art, typically an audiologist, using a variety of sounds, including pure tones and warble tones, and an audiometer. The result is displayed in an audiogram to show the difference in the hearing threshold for the individual and that of a normal hearing listener at 6 to 8 audio frequencies provided by the audiometer. Additional information is collected to characterize the sensitivity of the individual to loud sounds. This combined information is a measure of the individual's dynamic range of hearing. Various protocols or formulas (such as the Half Gain rule, NAL, and POGO) have been used to define the desired hearing aid performance that would best serve the impaired individual. The hearing aid(s) that most closely matches the desired performance are then selected by the dispenser. In the fitting step, the dispenser fine tunes the adjustable features in the hearing aid to achieve the best match to the desired performance.
In recent years, the perceived loudness of sounds within the dynamic range is also measured, and new protocols, such as IHAFF and FIG6, have been developed to provide the dispenser guidance on the selection and adjustment of compression aids. It is common practice for the dispenser to read a list, or to use a recorded list, of words to the hearing impaired individual, with and without the hearing aid, to determine the improvement in hearing with the aid.
The prior art hearing aid fitting adjustment procedure can be quite long and tedious, and its accuracy is limited because it is only guided by the fitting protocols and the experience/training of the dispenser to interpret the results of the work list test. While hearing loss has some typical patterns addressed by the fitting protocols, hearing loss is a highly specific condition that varies greatly from one individual to another such that the fitting protocols are not very accurate. As hearing aid technology has advanced with programmable and digital hearing aids, the range and number of parameters that can be electronically adjusted have increased. Fitting protocols have not developed as rapidly as hearing aid technology, and the fitting time has increased significantly, leading to sub- optimized performance. Summary Of The Invention
The present invention is directed to a computer system method an apparatus for optimizing and automating the fitting of hearing aids based on speech material (not tones) as the input source to measure the performance of the individual using the aid. Other features and advantages of the invention will be apparent from the following specification taken in conjunction with the following drawings. Brief Description Of The Drawings
Figure 1 illustrate a flow diagram of the overall fitting process of the present invention; Figure 1 A illustrates a more detailed flow diagram for the determination of an imputed inverse transform, as used in the fitting process of Figure 1 ;
Figure IB illustrates a more detailed flow diagram of the optimization process as used in the fitting process of Figure 1 ; Figure 2 illustrates a hearing impaired individual training the speech recognition engine (SRE) to learn to recognize words dictated by the individual as read from the SRE computer monitor;
Figure 3 illustrates the hearing impaired individual with relevant hardware arrangement; and
Figure 4 illustrates a count of words in an error list as the optimization process proceeds. Detailed Description Of The Preferred Embodiment
While this invention is susceptible of embodiments in many different forms, there is shown in the drawings and will herein be described in detail a preferred embodiment of the invention with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the broad aspect of the invention to the embodiment illustrated. The overall fitting process begins by having a hearing impaired subject train a voice/speech recognition engine (SRE) computer to recognize words as read from a visual presentation by the SRE on a computer monitor training screen. Subsequently, the dispenser fits a programmable hearing aid on the hearing impaired subject and connects the hearing aid to the program adjust module, such as Noah, which is also resident in the computer. A computer system 10 for optimizing and automating the fitting of hearing aids based on speech material (not tones) as an input source to measure performance of a hearing impaired individual using the hearing aid is illustrated in Figure 3. The computer system includes, as resident software, an SRE module, a Noah module, an imputed inverse transform module and an optimization module. Referring to the Figures, speech material consisting of nonsense sentences or un-related words from a word list that are very rich in frequency content and replete with time and amplitude variations is stored in the memory of the computer system 10. The stored speech material is presented aurally by the computer system 10 by means of a speaker 12 to the hearing impaired individual wearing an electronically adjustable hearing aid 14. The hearing aid 14 is connected to the computer system 10 by a cable, or some form of wireless data transfer. The individual identifies the words that are heard by repeating them back into the computer system 10 via a microphone 16 (Fig. 2), which then compares this input to original speech material and lists the incorrect words in an error file in the computer system 10.
As illustrated in Figures 3 and 4, by considering the incorrectly identified words and using pre-knowledge of their frequency content and their time and amplitude variations, the computer system 10 calculates an imputed inverse transform for a digital (DSP) aid and guides the adjustable parameters within the imputed inverse transform in a programmable DSP aid in an optimization routine to reduce the error list to a minimum through repeated trials. The computer system 10 can also adjust the parameters in a fixed program DSP aid or an analog aid in an optimization routine to reduce the error list to a minimum through repeated trials.
Since the optimization routine is based on mathematical concepts, such as the Simplex algorithm or those used in multi-dimensional servo control systems, the fitting is highly time efficient, accurate and independent of the experience of the dispenser. A further benefit is that the fitting is completely automatic, leading to lower hearing aid distribution cost.
To facilitate the automation, the hearing impaired subject repeats the speech material into the microphone 16 connected to the SRE module, a voice/speech recognition engine that is a part of the computer system 10. Keyboard entry or touch screens might also be used to enter the subject's repeated speech material into the computer system 10, but many subjects are not skilled with this form of data entry. Another party, such as the dispenser, could enter data, but this would not be automated and would not lower the cost of dispensing. While the specific embodiment has been illustrated and described, numerous modifications come to mind without significantly departing from the spirit of the invention and the scope of protection is only limited by the scope of the accompanying Claim.

Claims

CLAIMSWhat I claim is:
1. A method of optimizing hearing aid adjustments comprising: providing a computer; providing speech material consisting of nonsense sentences or un-related words from a word list, said words being rich in frequency content and replete with time and amplitude variations; presenting said speech material aurally to a hearing impaired individual wearing an electronically adjustable hearing aid; repeating the words; comparing the repeated words to the original speech material and identifying the incorrect words in an error file; considering the incorrectly identified words using pre-knowledge of their frequency content and their time and amplitude variations; and calculating an imputed inverse transform for a digital (DSP) aid.
2. A system for optimizing hearing aid adjustments comprising: a computer system having a memory; speech material stored in said computer memory, said speech material consisting of nonsense sentences or un-related words from a word list, said words being rich in frequency content and replete with time .and .amplitude variations; said computer system including means for presenting said stored speech material aurally to a hearing impaired individual wearing an electronically adjustable hearing aid, means for receiving the words repeated by said individual, means for comparing the repeated words to the original speech material and identifying the incorrect words in an error file; means for considering the incorrectly identified words using pre-knowledge of their frequency content .and their time and amplitude variations; and means for calculating an imputed inverse transform for a digital (DSP) aid.
PCT/US1998/025950 1997-12-12 1998-12-07 Automatic system for optimizing hearing aid adjustments WO1999031937A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU16307/99A AU1630799A (en) 1997-12-12 1998-12-07 Automatic system for optimizing hearing aid adjustments

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US6814197P 1997-12-12 1997-12-12
US60/068,141 1997-12-12

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WO (1) WO1999031937A1 (en)

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7020581B2 (en) 2002-10-18 2006-03-28 Medacoustics Research & Technology Medical hearing aid analysis system
US7181297B1 (en) 1999-09-28 2007-02-20 Sound Id System and method for delivering customized audio data
EP1767060A2 (en) * 2004-06-14 2007-03-28 Johnson & Johnson Consumer Companies, Inc. At-home hearing aid training system and method
WO2010017156A1 (en) * 2008-08-04 2010-02-11 Audigence, Inc. Automatic performance optimization for perceptual devices
WO2010117711A1 (en) * 2009-03-29 2010-10-14 University Of Florida Research Foundation, Inc. Systems and methods for tuning automatic speech recognition systems
US8401199B1 (en) 2008-08-04 2013-03-19 Cochlear Limited Automatic performance optimization for perceptual devices
US8755533B2 (en) 2008-08-04 2014-06-17 Cochlear Ltd. Automatic performance optimization for perceptual devices
US8892233B1 (en) 2014-01-06 2014-11-18 Alpine Electronics of Silicon Valley, Inc. Methods and devices for creating and modifying sound profiles for audio reproduction devices
US8977376B1 (en) 2014-01-06 2015-03-10 Alpine Electronics of Silicon Valley, Inc. Reproducing audio signals with a haptic apparatus on acoustic headphones and their calibration and measurement
US9319812B2 (en) 2008-08-29 2016-04-19 University Of Florida Research Foundation, Inc. System and methods of subject classification based on assessed hearing capabilities
US9344817B2 (en) 2000-01-20 2016-05-17 Starkey Laboratories, Inc. Hearing aid systems
US9553984B2 (en) 2003-08-01 2017-01-24 University Of Florida Research Foundation, Inc. Systems and methods for remotely tuning hearing devices
US9844326B2 (en) 2008-08-29 2017-12-19 University Of Florida Research Foundation, Inc. System and methods for creating reduced test sets used in assessing subject response to stimuli
US10986454B2 (en) 2014-01-06 2021-04-20 Alpine Electronics of Silicon Valley, Inc. Sound normalization and frequency remapping using haptic feedback

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3009204A1 (en) * 1980-03-11 1981-09-24 Robert Bosch Gmbh, 7000 Stuttgart Audiometric measuring arrangement obviating subjective evaluation - has memories for original and repeated signals for supplying Fourier transform unit and difference evaluator
EP0360909A1 (en) * 1988-09-30 1990-04-04 Siemens Audiologische Technik GmbH Speech practising apparatus

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3009204A1 (en) * 1980-03-11 1981-09-24 Robert Bosch Gmbh, 7000 Stuttgart Audiometric measuring arrangement obviating subjective evaluation - has memories for original and repeated signals for supplying Fourier transform unit and difference evaluator
EP0360909A1 (en) * 1988-09-30 1990-04-04 Siemens Audiologische Technik GmbH Speech practising apparatus

Cited By (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7181297B1 (en) 1999-09-28 2007-02-20 Sound Id System and method for delivering customized audio data
US9344817B2 (en) 2000-01-20 2016-05-17 Starkey Laboratories, Inc. Hearing aid systems
US9357317B2 (en) 2000-01-20 2016-05-31 Starkey Laboratories, Inc. Hearing aid systems
US7020581B2 (en) 2002-10-18 2006-03-28 Medacoustics Research & Technology Medical hearing aid analysis system
US9553984B2 (en) 2003-08-01 2017-01-24 University Of Florida Research Foundation, Inc. Systems and methods for remotely tuning hearing devices
EP1767060A4 (en) * 2004-06-14 2009-07-29 Johnson & Johnson Consumer At-home hearing aid training system and method
EP1767060A2 (en) * 2004-06-14 2007-03-28 Johnson & Johnson Consumer Companies, Inc. At-home hearing aid training system and method
US8401199B1 (en) 2008-08-04 2013-03-19 Cochlear Limited Automatic performance optimization for perceptual devices
US8755533B2 (en) 2008-08-04 2014-06-17 Cochlear Ltd. Automatic performance optimization for perceptual devices
WO2010017156A1 (en) * 2008-08-04 2010-02-11 Audigence, Inc. Automatic performance optimization for perceptual devices
US9844326B2 (en) 2008-08-29 2017-12-19 University Of Florida Research Foundation, Inc. System and methods for creating reduced test sets used in assessing subject response to stimuli
US9319812B2 (en) 2008-08-29 2016-04-19 University Of Florida Research Foundation, Inc. System and methods of subject classification based on assessed hearing capabilities
WO2010117711A1 (en) * 2009-03-29 2010-10-14 University Of Florida Research Foundation, Inc. Systems and methods for tuning automatic speech recognition systems
US8977376B1 (en) 2014-01-06 2015-03-10 Alpine Electronics of Silicon Valley, Inc. Reproducing audio signals with a haptic apparatus on acoustic headphones and their calibration and measurement
US8891794B1 (en) 2014-01-06 2014-11-18 Alpine Electronics of Silicon Valley, Inc. Methods and devices for creating and modifying sound profiles for audio reproduction devices
US9729985B2 (en) 2014-01-06 2017-08-08 Alpine Electronics of Silicon Valley, Inc. Reproducing audio signals with a haptic apparatus on acoustic headphones and their calibration and measurement
US8892233B1 (en) 2014-01-06 2014-11-18 Alpine Electronics of Silicon Valley, Inc. Methods and devices for creating and modifying sound profiles for audio reproduction devices
US10560792B2 (en) 2014-01-06 2020-02-11 Alpine Electronics of Silicon Valley, Inc. Reproducing audio signals with a haptic apparatus on acoustic headphones and their calibration and measurement
US10986454B2 (en) 2014-01-06 2021-04-20 Alpine Electronics of Silicon Valley, Inc. Sound normalization and frequency remapping using haptic feedback
US11395078B2 (en) 2014-01-06 2022-07-19 Alpine Electronics of Silicon Valley, Inc. Reproducing audio signals with a haptic apparatus on acoustic headphones and their calibration and measurement
US11729565B2 (en) 2014-01-06 2023-08-15 Alpine Electronics of Silicon Valley, Inc. Sound normalization and frequency remapping using haptic feedback
US11930329B2 (en) 2014-01-06 2024-03-12 Alpine Electronics of Silicon Valley, Inc. Reproducing audio signals with a haptic apparatus on acoustic headphones and their calibration and measurement

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