JP5037435B2 - Hearing aid adjustment - Google Patents

Description

  The present invention relates to a method for adjusting a hearing aid that sets an amplification factor that is most easily heard by a wearer.

  Hearing loss using a hearing aid can be broadly divided into conductive hearing loss, sensory hearing loss and mixed hearing loss. In the case of conductive hearing loss, abnormalities such as the eardrum and ossicles are the main causes, so hearing aid wearers adjust the hearing aid amplification factor for each frequency band based on data obtained by hearing tests using an audiometer. It is possible to improve hearing. However, in the case of sensorineural hearing loss and mixed hearing loss, the ability to discriminate between words is reduced, and there is a phenomenon that it is difficult to hear small sounds and even loud sounds (replenishment phenomenon, recruitment phenomenon). This is characterized by large individual differences, and there remains a problem as a method for adjusting a hearing aid.

  The main improvement measures for sensorineural hearing loss are to compress the dynamic range of the input sound to a sound pressure level that is easy for the wearer to hear, so that the sound pressure range of the wearer and the normal hearing person is the most easily heard by the wearer. Then calculate the sound pressure level and gain that can be heard best from the results of the hearing characteristics / sound intelligibility test of the wearer for each frequency band, and further operate the volume etc. to adjust the maximum sound pressure / minimum A hearing aid processing method of a digital hearing aid that sets a sound pressure range of sound pressure is known (see, for example, Patent Document 1).

  In addition, as a hearing aid equipped with a data logging function to record the usage status of the wearer, in order to collect various hearing environment data of the wearer, change and input a predetermined signal parameter such as selection of a preset program, volume adjustment, etc. Performance is improved by analyzing past history of hearing prosthesis movements by recording the trigger event information in combination with the environmental sound of the wearer when the signal matches a predetermined reference signal, etc. There is known a method of recording data in a hearing prosthesis designed to achieve the above (see, for example, Patent Document 2).

Japanese Patent No. 2904272 JP 2003-339760 A

  However, in the hearing aid processing method described in Patent Document 1, the hearing characteristics / sound intelligibility test is performed and the dynamic range compression and gain of the hearing aid are set. Therefore, the adjustment that is easy to hear becomes insufficient, and the wearer must change the range of the sound pressure level of the maximum sound pressure level and the minimum sound pressure level according to the sound environment by operating the volume.

  Further, in the technique described in Patent Document 2, the sound environment data of the wearer is collected by using the data logging function, but a method for adjusting the hearing aid using the sound environment data is specifically described. It has not been. In hearing aids having a data logging function that are currently on the market, the volume indication value selected by the wearer is sampled over a predetermined period with respect to a preset reference volume indication value, and the average is used as a new reference volume indication value. The wearer must adjust the volume because it is quiet, noisy, or unable to respond to changes in the sound environment that he or she wants to hear.

  The present invention has been made in view of such problems of the prior art, and an object of the present invention is to input signal levels and volume indication values calculated from input sound pressure levels that are actual sound environments. In view of the above data, it is intended to provide a method for adjusting a hearing aid that can set an amplification factor that is most easily heard by the wearer.

  In order to solve the above problem, the invention according to claim 1 is a method for adjusting a hearing aid comprising a data log and adjusting an amplification factor of an output sound pressure level with respect to an input sound pressure level by adjusting a volume. A data logging step for storing an input signal level and a volume indication value calculated from an input sound pressure level, a representative volume indication value calculation step for calculating a representative volume indication value for each sound pressure category of the input signal level, and an input signal An amplification factor calculation step for calculating a new amplification factor using the representative volume indication value, a preset reference volume indication value, and a preset amplification factor for each sound pressure category of the level is provided. .

  The invention according to claim 2 is the method of adjusting a hearing aid according to claim 1, wherein the input signal level is any one of an input sound level, a noise level, and a conversation sound level.

  The invention according to claim 3 is the method of adjusting a hearing aid according to claim 1 or 2, wherein when data is stored up to the memory capacity of the storage unit, new data is overwritten in order from the oldest stored data. It is.

According to the first and second aspects of the invention, the amplification factor that is most easily heard by the wearer is calculated by calculating the new amplification factor using the data of the input signal level and the volume indication value in various sound environments of the wearer. Can be set.

  According to the invention which concerns on Claim 3, adjustment of the hearing aid most suitable for the wearer's sound environment can be performed by using the newest data.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. Here, FIG. 1 is a block diagram for implementing a method for adjusting a hearing aid according to the present invention, FIG. 2 is a flowchart showing the procedure of the method for adjusting a hearing aid according to the present invention, and FIG. 3 is a diagram showing input / output characteristics of the hearing aid. FIG. 4 is a diagram showing the relationship between the conversation sound level and the volume instruction value, and FIG. 5 is a frequency distribution diagram of the input sound pressure level.

  As shown in FIG. 1, a hearing aid 1 that implements the method for adjusting a hearing aid according to the present invention includes a microphone 2, a DSP (Digital Signal Processor) 3, a volume 4, a switch 5, an earphone 6, and the like. Reference numeral 7 denotes a personal computer connected to the DSP 3. The microphone 2 converts the input sound into an electrical signal and outputs the converted electrical signal. The DSP 3 constitutes a signal processing unit 8, a storage unit 9, a timer 10, and the like. The volume 4 allows the wearer to adjust the volume. The earphone 6 converts the output signal of the signal processing unit 8 into an acoustic signal and outputs it as an audio signal.

  The signal processing unit 8 performs various types of signal processing on the electrical signal from the microphone 2 according to the set of coefficients (program pattern) that has been set, and outputs the electrical signal that has undergone signal processing. Further, the signal processing unit 8 calculates the input signal level, stores data in the storage unit 9 at regular time intervals by the timer 10, and manages time-series data storage management.

  The storage unit 9 includes a program storage unit 11 and a data storage unit 12. The program storage unit 11 stores a plurality of (for example, four types) program patterns. An identification number is given to the program pattern, and the wearer can switch the sound pattern according to the sound environment in which the hearing aid is used by the switch 5, or the hearing aid can be automatically switched according to the sound environment. The data storage unit 12 stores the input signal level, the selected instruction value data of the volume 4, the selected program pattern identification number data, and the like. The new gain due to readjustment of the hearing aid is overwritten and stored as a coefficient of the program pattern. Here, the volume instruction value is indicated by an amplification factor, but an identification number may be assigned and stored.

  The personal computer 7 incorporates a hearing aid adjustment program including a calculation program for calculating a new amplification factor and the like.

  A method for adjusting a hearing aid according to the present invention using the hearing aid 1 configured as described above will be described. As shown in FIG. 2, in the adjustment method of the hearing aid 1, first, in step SP1, initial setting is performed. Here, hearing data is collected by the hearing test using the audiometer of the wearer, sound field hearing data is collected by the hearing test in the sound field, and speech intelligibility data is collected by the speech speech intelligibility test. Sets the amplification factor of the output sound pressure level relative to the sound pressure level.

  For example, the relationship between the input sound pressure level and the output sound pressure level at a certain frequency is set as shown by a broken line (a) in FIG. This is an example in sound-sensitive hearing loss, and the amplification factor (the slope of the graph) is not constant, and the amplification factor is gradually lowered when the input sound pressure level exceeds 50 dBSPL. Further, the output sound pressure level is limited so as not to exceed 91 dBSPL.

  The output sound pressure level can be adjusted by the wearer operating the volume 4 to change the amplification factor. For example, the volume indication value (reference volume indication value) at the amplification factor set in the initial setting is set to −3 dB, and the wearer changes the indication value (● mark) of the volume 4 between 0 to −10 dB. The amplification factor can be adjusted. Here, when the volume instruction value is set to 0 dB, the output sound pressure becomes +3 dB with respect to the initially set output sound pressure.

  Next, in step SP2, the signal processing unit 8 calculates the input signal level from the input sound pressure level captured by the microphone 2, and stores this input signal level in the data storage unit 12 (data logging step). Either input sound level, noise level or conversation sound level is used as the input signal level, and in the case of input sound level, sound pressure classification for input sound level, noise level or conversation as input signal level sound pressure classification In the case of a sound level, a noise level sound pressure classification is set and used. Here, the calculation method of the input signal level will be described for the case of the input sound level, the noise level, and the conversation sound level.

  As a method for calculating the input sound level, a representative frequency is set in advance for each predetermined frequency band. For example, at a frequency of 200 Hz to 8 kHz, one frequency band divided into frequency bands is set to 200 Hz or more and less than 800 Hz, and the representative frequency is set to 500 Hz. Then, for each representative frequency in each frequency band, the sound pressure level for each representative frequency is repeatedly measured with respect to the input sound pressure level at a first designated time (eg, 0.05 seconds), and a second designated time (eg, An average value is calculated at intervals of 1 second).

  Furthermore, at intervals of a third designated time (for example, 30 minutes), as shown in FIG. 5, the sound pressure classification for input sound level (for example, at 4 dBSPL intervals, center 60 dBSPL (58 dBSPL or more and less than 62 dBSPL), center 64 dBSPL (62 dBSPL) The frequency of the average value calculated every second designated time is obtained for each above (less than 66 dBSPL)...), And the highest sound pressure classification for input sound level is calculated as the input sound level. In the example shown in FIG. 5, the input sound level is the center value 60 dBSPL of the sound pressure classification for the input sound level at the center 60 dBSPL (greater than or equal to 58 dBSPL and less than 62 dBSPL) whose frequency is indicated by diagonal lines. When there are a plurality of sound pressure sections having the highest frequency, the center value of the lowest sound pressure section is set as the input sound level, but this is not restrictive.

  Next, in the noise level calculation method, a representative frequency is set in advance for each predetermined frequency band. For example, at a frequency of 200 Hz to 8 kHz, one frequency band divided into frequency bands is set to 200 Hz or more and less than 800 Hz, and the representative frequency is set to 500 Hz. Then, for each representative frequency in each frequency band, the sound pressure level for each representative frequency is measured repeatedly for a first designated time (for example, 0.05 seconds) with respect to the input sound pressure level.

  Further, at the second designated time (for example, 1 second), the sound pressure classification for noise level (for example, at the 5 dBSPL interval, the center 60 dBSPL (57.5 dBSPL or more and less than 62.5 dBSPL), the center 65 dBSPL (62.5 dBSPL or more 67). .. less than 5 dBSPL))), and the center value of the sound pressure classification with the highest frequency is calculated as the primary noise level. When there are a plurality of sound pressure sections having the highest frequency, the center value of the sound pressure section having the lowest frequency is set as the primary noise level, but this is not restrictive.

  Next, in the third designated time (for example, 15 minutes), the frequency of the primary noise level calculated every second designated time is obtained, and the center value of the noise level sound pressure classification with the highest frequency is calculated as the noise level. When there are a plurality of sound pressure sections having the highest frequency, the center value of the sound pressure section having the lowest frequency is set as the noise level, but this is not restrictive.

Next, the conversation sound level is calculated from the noise level using a calculation formula. For example, C _L = α · N _t + β is used as the calculation formula. Here, C _L : conversation sound level, N _t : noise level, α, β: coefficients (for example, α = 0.38, β = 37.2) (“Effect of Psychological Feedback on Conversational Noise Reduction in Rooms” "By TSKORN THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA VOLUME 26 NUMBER 5). This method of calculating the conversation sound level is an example, and the present invention is not limited to this. The conversation sound level C _L can also be calculated by the personal computer 7 from the data of the noise level N _t instead of being calculated by the signal processor 8 inside the hearing aid 1.

  The data stored in the data storage unit 12 at a predetermined time interval (third designated time) includes input sound level as input signal data, data of either noise level or conversation sound level, and the selected volume 4 The indicated value data and the selected program pattern identification number data. The indication value and program pattern identification number of the volume 4 can be sampled by sampling at a second designated time (for example, 1 second) and calculating the frequency from the data. When the data storage capacity of the data storage unit 12 reaches the memory capacity, new data is overwritten in the oldest order. Although the amount of data to be stored varies depending on the predetermined time interval and the capacity of the data storage unit 12, for example, data for about two weeks is stored in the data storage unit 12.

  In this embodiment, data is stored at a predetermined time interval. However, the present invention is not limited to this, and the switching of the volume 4 and the program pattern may be used as a trigger. From the data sampled at such irregular intervals, the input signal level is calculated at a predetermined designated time, and the input signal level, the volume indication value, and the program pattern identification number are stored in time series, A new amplification factor can also be calculated.

  Next, in step SP3, it is determined whether or not the indication value of the volume 4 has been changed. If the indication value of volume 4 has been changed, the process proceeds to step SP4. On the other hand, when the indication value of the volume 4 has not been changed, the adjustment ends.

  In step SP4, an amplification factor adjustment operation is performed (adjustment step). When the adjustment work is completed, the process returns to the data logging process of step SP2. Here, the adjustment work of the amplification factor in the case of the conversation sound level will be described. The personal computer 7 incorporates an adjustment program for the hearing aid 1 including a calculation program based on a predetermined algorithm (described later).

  In the adjustment of the amplification factor, first, the data stored in the data storage unit 12 including the conversation sound level data of the hearing aid 1 is taken into the personal computer 7. Next, an optimum amplification factor (new amplification factor) is obtained by a predetermined algorithm (described later) using the data fetched into the personal computer 7. Next, the personal computer 7 resets the new amplification factor obtained by a predetermined algorithm as the coefficient of the program pattern of the hearing aid 1 stored in the program storage unit 11.

  The new amplification factor resetting process can also be performed in the hearing aid 1, for example, the DSP 3 without using the personal computer 7.

  The predetermined algorithm described above will be described in the case of the conversation sound level. First, as shown in FIG. 4, the volume indication value (1 dB interval from 0 dB to −10 dB) is set for each conversation sound level (each center value of the sound pressure classification for noise level, eg, from 40 dBSPL to 80 dBSPL at 5 dBSPL intervals). Find the frequency. Next, a representative volume instruction value is calculated for each conversation sound level (representative volume instruction value calculating step). The representative volume instruction value is the highest value.

  In consideration of the fact that the frequency distribution is dispersed, the average of the volume instruction values may be used, or when the dispersion of the frequency distribution is wide, the average of the amplification factors corresponding to the volume instruction values may be used. Good. In addition, when there are a plurality of sound pressure categories having the highest frequency, the lowest volume indication value may be used, and there is no limitation.

  Actually, the number of data of the volume instruction value for each conversational sound level is large, but here, assuming that it is as shown in FIG. 4, when the conversational sound level is 65 dBSPL, the number of samples is two (indicated by −6 dB marked with ●). -8 dB), and since these are dispersed, if these are averaged to the nearest volume indication value, the representative volume indication value is -7 dB.

  Next, the degree of change in the amplification factor is a value obtained by subtracting the reference volume instruction value set in the initial setting from the obtained representative volume instruction value. For example, as shown in FIG. 4, if the representative volume instruction value is −7 dB and the reference volume instruction value is −3 dB when the conversation sound level is 65 dBPL, the degree of change in the amplification factor when the conversation sound level is 65 dBSPL is −4 dB. Become. Therefore, the new amplification factor is a value obtained by adding −4 dB to the amplification factor before adjustment (amplification factor calculation step).

  In the example shown in FIG. 4, when the conversation sound level is low (55 dBSPL or less), the volume 4 is not operated with the reference volume instruction value, but when the conversation sound level is high (60 dBSPL or more), the amplification factor is decreased. Since the volume 4 is operated, the output sound is too loud with the reference volume instruction value.

  In the example shown in FIG. 4, when the amplification factor adjustment operation is performed with a predetermined algorithm, as shown by a solid line (b) in FIG. 3, an adjustment to lower the amplification factor of a high input sound pressure level (55 dBSPL or more and 75 dBSPL or less) is performed. It is possible to make the input / output characteristics of the hearing aid 1 in accordance with the hearing characteristics of the wearer. Such an amplification factor adjustment operation is sequentially performed for each predetermined frequency band at predetermined time intervals.

  ADVANTAGE OF THE INVENTION According to this invention, the adjustment method of the fine hearing aid suitable for a wearer's symptom can be provided by calculating the amplification factor which is most easy to hear for a wearer.

The block block diagram which implements the adjustment method of the hearing aid concerning this invention The flowchart which shows the procedure of the adjustment method of the hearing aid concerning this invention. Diagram showing input / output characteristics of hearing aid The figure which shows the relationship between conversation sound level and volume indication value Frequency distribution chart of input sound level

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Hearing aid, 2 ... Microphone, 3 ... DSP, 4 ... Volume, 5 ... Switch, 6 ... Earphone, 7 ... Personal computer, 8 ... Signal processing part, 9 ... Memory | storage part, 10 ... Timer, 11 ... Program memory | storage part, 12: Data storage unit.

Claims (3)

A method for adjusting a hearing aid that includes a data log and adjusts an amplification factor of an output sound pressure level with respect to an input sound pressure level by adjusting a volume, the input signal level and volume calculated from an input sound pressure level that is a sound environment of a wearer A data logging process for storing an instruction value; a representative volume instruction value calculating process for calculating a representative volume instruction value for each sound pressure section of the input signal level; and the representative volume instruction value for each sound pressure section of the input signal level A method for adjusting a hearing aid, comprising: an amplification factor calculation step for calculating a new amplification factor using a set reference volume instruction value and a preset amplification factor. 2. The method for adjusting a hearing aid according to claim 1, wherein the input signal level is any one of an input sound level, a noise level, and a conversation sound level. The method for adjusting a hearing aid according to claim 1 or 2, wherein when data is stored up to the memory capacity of the storage unit, new data is overwritten in order from the oldest stored data. .

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