Abstract:
A programmable hearing aid apparatus includes a processor, digital-to-analog converter, audio output section, memory and a counter. The processor executes one or more available programs, which are stored in the memory, for processing digital audio signals. The digital-to-analog converter generates output analog audio signals based on the digital audio signals. The audio output section receives and amplifies the output analog audio signals, generates audible sound based thereon and provides the audible sound to a person using the hearing aid. The counter generates a counter value based on a count of events that are indicative of the application of power to or the removal of power from the apparatus. After a predetermined elapsed time, the processor determines which of the available programs has been used most in processing the digital audio signals, where the determination of elapsed time is based at least in part on the counter value. The counter may count occurrences of events indicative of the removal and replacement of the battery, such as a number of times a contact switch on a battery compartment door is electrically opened or closed. The counter may also count a number of times the voltage across the battery increases by a substantial amount indicating that a weak battery has been replaced with a fresh battery. The counter may also count a number of times an on/off switch is operated by a user.

Description:
[0001]    This application is a continuation-in-part of and claims priority to U.S. patent application Ser. No. 11/739,781 filed Apr. 25, 2007, entitled “Preprogrammed Hearing Assistance Device with Program Selection Based on Patient Usage.” 
     
    
     FIELD 
       [0002]    This invention relates to the field of hearing assistance devices. More particularly, this invention relates to a system for programming the operation of a hearing assistance device based on usage of the device by a patient. 
       BACKGROUND 
       [0003]    Hearing loss varies widely from patient to patient in type and severity. As a result, the acoustical characteristics of a hearing aid must be selected to provide the best possible result for each hearing impaired person. Typically, these acoustical characteristics of a hearing aid are “fit” to a patient through a prescription procedure. Generally, this has involved measuring hearing characteristics of the patient and calculating the required amplification characteristics based on the measured hearing characteristics. The desired amplification characteristics are then programmed into a digital signal processor in the hearing aid, the hearing aid is worn by the patient, and the patient&#39;s hearing is again evaluated while the hearing aid is in use. Based on the results of the audiometric evaluation and/or the patient&#39;s comments regarding the improvement in hearing, or lack thereof, an audiologist or dispenser adjusts the programming of the hearing aid to improve the result for the patient. 
         [0004]    As one would expect, the fitting procedure for a hearing aid is generally an interactive and iterative process, wherein an audiologist or dispenser adjusts the programming of the hearing aid, receives feedback from the patient, adjusts the programming again, and so forth, until the patient is satisfied with the result. In many cases, the patient must evaluate the hearing aid in various real world situations outside the audiologist&#39;s or dispenser&#39;s office, note its performance in those situations and then return to the audiologist or dispenser to adjust the hearing aid programming based on the audiologist&#39;s or dispenser&#39;s understanding of the patient&#39;s comments regarding the patient&#39;s experience with the hearing aid. 
         [0005]    One of the significant factors in the price of a hearing aid is the cost of the audiologist&#39;s or dispenser&#39;s services in fitting and programming the device, along with the necessary equipment, such as software, computers, cables, hyproboxes, etc. If the required participation of the audiologist and/or dispenser and the fitting equipment can be eliminated or at least significantly reduced, the cost of a hearing aid can be significantly reduced. 
         [0006]    The complexity and cost of fitting hearing assistance devices in general also applies in the fitting of tinnitus masking devices. Tinnitus is a condition wherein a person experiences a sensation of noise (as a ringing or roaring) that is caused from a condition (such as a disturbance of the auditory nerve, hair cells, temporal mandibular joint or medications, to name a few. Tinnitus is a significant problem for approximately 50 million people each year, and some people only find relief with tinnitus maskers. A tinnitus masker looks like a hearing aid, but instead of amplifying sensed sound, it produces a sound, such as narrow-band noise, that masks the patient&#39;s tinnitus. Some of these instruments have a trim pot that is used to change the frequency of the masking noise. Such instruments may also have a volume control so the user may select the intensity of the masking that works best. 
         [0007]    Most tinnitus maskers are prescribed to patients who do not have significant hearing loss, and the masking sound is designed to be more acceptable to the patient than the tinnitus. For most patients that have significant hearing loss, hearing aids can also provide tinnitus relief. However, there are some patients that need both amplification and tinnitus masking. 
         [0008]    The most appropriate masking stimuli to be generated by a tinnitus masker is usually determined by an audiologist or dispenser during a fitting procedure. Like the fitting of a hearing aid, the fitting procedure for a tinnitus masker also tends to be an iterative process which significantly increases the overall cost of the masking device. 
         [0009]    What is needed, therefore, is a programmable hearing assistance device that does not require a fitting procedure conducted by an audiologist or dispenser. To obviate the necessity of the programming equipment and the necessity of an audiologist or dispenser fitting procedure, a programmable hearing assistance device is needed which is automatically programmed based on selections made by a patient while using the device or based on usage patterns of the patient. This need applies to hearing aids as well as to tinnitus masking devices. 
       SUMMARY 
       [0010]    The above and other needs are met by a programmable apparatus for improving perception of sound by a person. In one embodiment, the apparatus includes a processor, digital-to-analog converter, audio output section and means for generating first and second control signals. The processor executes one or more available programs for processing digital audio signals based on control signals. The digital-to-analog converter generates output analog audio signals based on the digital audio signals. The audio output section receives and amplifies the output analog audio signals, generates audible sound based thereon and provides the audible sound to the person. The memory stores programs for processing the digital audio signals according to various acoustical configurations or with tinnitus masking stimuli. Based on an action by the person, a first control signal is generated for switching from one available program to another available program. Also based on an action by the person, a second control signal is generated for designating at least one of the available programs as a chosen program. Based on the first control signal, the processor ceases execution of one of the available programs and commences execution of another of the available programs. Based on the second control signal, the processor designates at least one of the available programs as a chosen program for continued use. 
         [0011]    In preferred embodiments, the means for generating the first and second control signals comprise a momentary push button switch and a controller. When activated by the person, the momentary push button switch changes from a first state to a second state. The controller generates the control signals based on periods of time during which the momentary push button switch is held in the second state. For example, the controller generates the first control signal when the momentary push button switch is held in the second state for a period of time exceeding a first time. The controller generates the second control signal when the momentary push button switch is held in the second state for a period of time exceeding a second time. 
         [0012]    In one embodiment, the programmable apparatus is a hearing aid device and the one or more available programs comprise acoustical configuration programs. In another embodiment, the programmable apparatus is a tinnitus masking device and the one or more available programs comprise masking stimuli programs. In yet another embodiment, the programmable apparatus is a combination hearing aid device and tinnitus masking device, and the one or more available programs comprise acoustical configuration programs and masking stimuli programs. 
         [0013]    In some embodiments, the programmable apparatus includes a timer for timing how long each of the available programs is used in processing digital audio signals. Based on how long each of the available programs is used, the processor designates at least one of the available programs as a chosen program for continued use. 
         [0014]    In another aspect, the invention provides a method for improving perception of sound by a person. The method includes steps of (a) storing in a memory device one or more available programs for processing digital audio signals, (b) processing the digital audio signals based on execution of the one or more available programs, (c) generating output analog audio signals based on the digital audio signals, (d) receiving and amplifying the output analog audio signals to generate audible sound based thereon, (e) generating a first control signal to switch from one available program to another available program based upon an action by the person, (f) generating a second control signal to designate at least one of the available programs as a chosen program based upon an action by the person, (g) ceasing execution of one of the available programs and commencing execution of another of the available programs based on the first control signal, and (h) designating at least one of the available programs as a chosen program based on the second control signal. 
         [0015]    In yet another aspect, the invention provides a programmable hearing aid apparatus comprising a processor, digital-to-analog converter, audio output section, memory and a counter. The processor executes one or more available programs for processing digital audio signals. The digital-to-analog converter generates output analog audio signals based on the digital audio signals. The audio output section receives and amplifies the output analog audio signals, generates audible sound based thereon and provides the audible sound to a person using the hearing aid. The memory stores the one or more available programs for processing the digital audio signals. The counter generates a counter value based on a count of events that are indicative of the application of power to or the removal of power from the programmable apparatus. After a predetermined elapsed time, the processor determines which of the one or more available programs has been used most in processing the digital audio signals. Preferably, the determination of elapsed time is based at least in part on the counter value. 
         [0016]    In some embodiments, the programmable apparatus includes a battery for providing power, and the counter is operable to count occurrences of events that are indicative of the removal and replacement of the battery. In one preferred embodiment, the apparatus includes a battery compartment door and a contact switch attached to the battery compartment door. The counter of this embodiment is operable to count a number of times the contact switch is electrically opened or closed. 
         [0017]    In some embodiments, the programmable apparatus includes voltage level detection circuitry for detecting a voltage across the battery. In these embodiments, the counter is operable to count a number of times the voltage across the battery increases by a substantial amount indicating that a weak battery has been replaced with a fresh battery. 
         [0018]    Some preferred embodiments include an on/off switch for turning the apparatus on and off. In these embodiments, the counter is operable to count a number of times the on/off switch is operated by a user. 
         [0019]    Further details of each of these and other embodiments of the invention are provided in the drawings and in the detailed description. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0020]    Further advantages of the invention are apparent by reference to the detailed description in conjunction with the figures, wherein elements are not to scale so as to more clearly show the details, wherein like reference numbers indicate like elements throughout the several views, and wherein: 
           [0021]      FIG. 1  depicts a functional block diagram of a hearing assistance device according to a preferred embodiment of the invention; 
           [0022]      FIGS. 2 and 3  depict a functional flow diagram of the programming of a hearing assistance device according to a first embodiment of the invention; 
           [0023]      FIGS. 4 and 5  depict a functional flow diagram of the programming of a hearing assistance device according to a second embodiment of the invention; 
           [0024]      FIG. 6  depicts a functional block diagram of a tinnitus masking device according to a preferred embodiment of the invention; 
           [0025]      FIG. 7  depicts a functional flow diagram of the programming of a tinnitus masking device according to a preferred embodiment of the invention; and 
           [0026]      FIG. 8  depicts a functional block diagram of components of a hearing assistance device according to a preferred embodiment of the invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0027]      FIG. 1  depicts one embodiment of a hearing assistance device  10  for improving the hearing of a hearing-impaired patient. The device  10  of  FIG. 1  is also referred to herein as a hearing aid. Another embodiment of a hearing assistance device is a tinnitus masking device as shown in  FIG. 6  which is discussed in more detail hereinafter. 
         [0028]    As shown in  FIG. 1  the hearing assistance device  10  includes one or more microphones  12   a - b  for sensing sound and converting the sound to analog audio signals. The analog audio signals generated by the microphones  12   a - b  are converted to digital audio signals by analog-to-digital (A/D) converters  14   a - 14   b . The digital audio signals are processed by a digital processor  16  to shape the frequency envelope of the digital audio signals to enhance those signals in a way which will improve audibility for the wearer of the hearing assistance device. Further discussion of various programs for processing the digital audio signals by the processor  16  is provided below. Thus, the processor  16  generates digital audio signals that are modified based on the programming of the processor  16 . The modified digital audio signals are provided to a digital-to-analog (D/A) converter  18  which generates analog audio signals based on the modified digital audio signals. The analog audio signals at the output of the D/A converter  18  are amplified by an audio amplifier  20 , where the level of amplification is controlled by a volume control  34  coupled to a controller  24 . The amplified audio signals at the output of the amplifier  20  are provided to a sound generation device  22 , which may be an audio speaker or other type of transducer that generates sound waves or mechanical vibrations which the wearer perceives as sound. The amplifier  20  and sound generation device  22  are referred to collectively herein as an audio output section  19  of the device  10 . 
         [0029]    With continued reference to  FIG. 1 , some embodiments of the invention include a telephone coil  30 . The telephone coil  30  is small coil of wire for picking up the magnetic field emitted by the ear piece of some telephone receivers or loop induction systems when the hearing assistance device  10  is disposed near such a telephone receiver or loop induction system. Signals generated by the telephone coil  30  are converted to digital signals by an A/D converter  14   c  and are provided to the processor  16 . As discussed in more detail below, the converted digital signals from the telephone coil  30  may be used in some embodiments of the invention for resetting or reprogramming the processor  16 , or controlling the operation of the hearing assistance device  16  in other ways. 
         [0030]    Some embodiments of the invention also include a wireless interface  32 , such as a Bluetooth interface, for receiving wireless signals for resetting or reprogramming the processor  16 . In some embodiments, the wireless interface  32  is also used to control the operation of the device  10 , including selection of acoustical configuration programs or masking stimuli programs. The wireless interface  32  may also be used to wirelessly deliver an audio signal to the device  10 , such as a music signal transmitted from a wireless transmitter attached to a CD player, or the audio portion of a television program transmitted from a wireless transmitter connected to a television tuner. In various embodiments, the wireless interface  32  comprises a WiFi link according to the IEEE 802.11 specification, an infrared link or other wireless communication link. 
         [0031]    As shown in  FIG. 1 , a manually operated input device  28 , also referred to herein as a momentary switch or push button, is provided for enabling the wearer to control various aspects of the operation and programming of the hearing assistance device  10 . The push button  28  is preferably very small and located on an outer surface of a housing associated with the device  10 . The push button  28  is located on a portion of the housing that is accessible to the wearer while the wearer is wearing and using the device  10 . 
         [0032]    For example, the device  10  may be configured as a behind-the-ear (BTE), in-the-ear (ITE) instrument, with the push button  28  located on an accessible surface of the BTE or ITE instrument. An example of a hearing aid having BTE and ITE portions is described in U.S. Patent Application Publication 2006/0056649, where reference number 34 of FIG. 1 of that publication indicates one possible location for a push button switch on the BTE portion of a hearing aid. The push button  28  may also be located on the ITE portion. It will be appreciated that the invention is not limited to any particular configuration of the device  10 . In various embodiments, the device  10  may comprise an open fit hearing aid, a canal hearing aid, a half-shell configuration, a BTE device, an ITE device or a completely in canal (CIC) device. 
         [0033]    The push button  28  is electrically connected to a controller  24  which generates digital control signals based on the state (open or closed) of the switch of the push button  28 . In a preferred embodiment of the invention, the digital control signals are generated by the controller  24  based on how long the push button  28  is pressed. In this regard, a timer is included in the controller  24  for generating a timing signal to time the duration of the pressing of the button  28 . Further aspects of the operation of the controller  24  and the push button  28  are described in more detail below. 
         [0034]    A second push button  328  may be included in embodiments of the invention that combine hearing aid functions with tinnitus masking functions. In these embodiments, a push button  328  is used to control the selection of tinnitus masking programs as described in more detail hereinafter. Alternatively, a single push button may be used for first programming the hearing aid functions and then programming the tinnitus masking functions. 
         [0035]    Nonvolatile memory  26 , such as read-only memory (ROM), programmable ROM (PROM), electrically erasable PROM (EEPROM), or flash memory, is provided for storing programming instructions and other operational parameters for the device  10 . Preferably, the memory  26  is accessible by the processor  16  and/or the controller  24 . 
         [0036]    According to preferred embodiments of the invention, the hearing assistance device  10  is operable in several different modes as determined by its programming. As the terms are used herein, “programs” and “programming” refers to one or more sets of instructions that are carried out by the processor  16  in shaping the frequency envelope of digital audio signals to enhance those signals to improve audibility for the wearer of the hearing assistance device  10 . “Programs” and “programming” also refers to the instructions carried out by the processor  16  in determining which of several stored enhancement programs provides the best improvement for the wearer.  FIGS. 2-5  depict the process flow of some exemplary methods for selecting the most effective hearing enhancement program for the wearer. 
         [0037]      FIGS. 2 and 3  depict a process flow according to one preferred embodiment of the invention wherein the selection of the most effective enhancement program is based upon a “trial and error” interactive and iterative method, where the wearer of the device evaluates several options for enhancement programs and chooses one or more programs that provide the best enhancement for the individual wearer. As shown in  FIG. 2 , a first step in the method is to store in memory  26  some number (N) of primary acoustical configuration programs for shaping the acoustical characteristics of the hearing assistance device  10  (step  100 ). This step may be performed at the time of manufacture of the hearing assistance device  10  or at a later time, such as during a reprogramming procedure. In a preferred embodiment of the invention, seven primary acoustical characteristic configuration programs are loaded into the memory  26  (N=7). However, it will be appreciated that any number of programs may be initially loaded into memory  26 , and the invention is not limited to any particular number. 
         [0038]    As the phrase is used herein, a “primary acoustical characteristic configuration program” is an algorithm that sets the audio frequency shaping or compensation provided in the processor  16 . These programs or algorithms may also be referred to by audiologists or dispensers as “gain-frequency response prescriptions.” Examples of generally accepted primary acoustical configuration programs include NAL (National Acoustic Laboratories; Bryne &amp; Tonisson, 1976), Berger (Berger, Hagberg &amp; Rane, 1977), POGO (Prescription of Gain and Output; McCandless &amp; Lyregaard, 1983), NAL-R (NAL-Revised; Byrne &amp; Dillon, 1986), POGO II (Schwartz, Lyregaard &amp; Lundh, 1988), NAL-RP (NAL-Revised, Profound; Byrne, Parkinson &amp; Newall, 1991), FIG. 6 (Killion &amp; Fikret-Pasa, 1993) and NAL-NL1 (NAL nonlinear; Dillon, 1999). It will be appreciated that other primary acoustical configuration programs could be used in association with the methods described herein, and the above list should not be construed as limiting the scope of the invention in any way. 
         [0039]    A “secondary acoustical characteristic configuration program” as that phrase is used herein refers to a variation on one of the primary programs. For example, in one of the primary programs, a parameter for gain at 1000 Hz may be set to a value of 20 dB which is considered to be in or near the center of a range for an average hearing loss patient. In an example of a related secondary program, the parameter for gain at 1000 Hz may be set to a value of 25 dB which is just above the “standard” value. Accordingly, another related secondary program may have the parameter for gain at 1000 Hz set to a value of 15 dB which is just below the “standard” value. There may be any number of secondary programs that include various variations of parameters which in the associated primary program are set to a standard or average value. Preferably, 2×N number of secondary acoustical configuration programs are loaded into memory at step  100 . For example, there may be two secondary programs associated with each primary program. 
         [0040]    In the preferred embodiment of the invention, a feedback canceller algorithm is also stored in the memory  26  of the device  10 . An example of a feedback canceller algorithm is described in U.S. Patent Application Publication 2005/0047620 by Robert Fretz. As described in more detail below, such an algorithm is used to set the acoustical gain levels in the processor  16  and/or the amplifier  20  to avoid audio feedback in the device  10 . 
         [0041]    At some point after the initial programming of the device (step  100 ), a wearer inserts the device  10  into the ear canal (in the case of an ITE device) or places the device  10  behind the ear (in the case of a BTE device) with the associated connections to the ear canal (step  102 ). Once the device  10  is in position, the wearer presses the button  28  for some extended period of time T 1 , such as 60 seconds, to activate the device  10  and initialize the feedback canceller program (step  104 ). According to a preferred embodiment of the invention, the feedback canceller program generates and stores acoustical coefficients that will be applicable to all of the primary and secondary acoustical configuration programs stored in the memory  26 . 
         [0042]    Once the feedback canceller program has performed its initialization procedure, the wearer can cycle through the N number of available primary acoustical configuration programs and try each to determine which provides the best enhancement for the wearer&#39;s hearing loss. The wearer does this by pressing the button  28  for at least some period of time T 2 , such as one second, to switch from one program to the next (step  108 ). For example, a first program may be executed by the processor  16  when the device  10  is first powered on. When the wearer presses the button  28  for at least one second, a second program is executed by the processor  16  (step  120 ). In some embodiments, the device  10  generates two beeps (step  118 ) to indicate to the selection of the second program. When the wearer presses the button  28  again for at least one second, a third program is executed by the processor  16  (step  120 ) and the device  10  generates three beeps to indicate that the third program is selected. This continues until the wearer has cycled through the N number of programs (such as seven). If the wearer presses the button  28  again for at least one second, the first program is loaded again. This process is represented by steps  108 - 122  of  FIG. 2 . To cycle through programs quickly, the wearer may press the button  28  several times consecutively until the desired program is selected. At this point, some number of beeps are generated to indicate which program is selected. 
         [0043]    If it is determined that the button  28  is pressed for less than one second (step  110 ), then no new program is loaded and the process waits for the next button press (step  122 ). This prevents inadvertent switching from one program to the next due to an accidental press of the button  28 . 
         [0044]    Once the wearer has had a chance to evaluate all of the available primary programs, the wearer may find that some smaller number of the programs, such as two, seem to be used most because they provide the best hearing enhancement for the user in various situations. For example, one of the programs may provide the best performance in normal quiet conversation settings. Another of the programs may provide the best performance in a noisy setting, such as in a crowded room. A preferred embodiment of the invention allows the user to eliminate programs that are not used or rarely used, and to evaluate some secondary programs that are variations on the best performing programs. As described below, this is accomplished by pressing the push button  28  for a time T 3 , such as 30 seconds, which is longer than the time T 2 . 
         [0045]    As shown in  FIG. 2 , if it is determined that the button  28  is pressed for a time T 3  or longer (step  124 ), such as 30 seconds, the processor  16  sets a flag or stores a value indicating that the currently-loaded primary program has been designated as a chosen program (step  126 ). At this point, the device  10  generates a distinctive sound (step  128 ) to indicate to the wearer that a program has been chosen. In a preferred embodiment, the device  10  allows the user to choose two of the N number of primary acoustical configuration programs. However, it will be appreciated that the device  10  could accommodate designation of more or fewer than two primary acoustical configuration programs as chosen. If it is determined at step  130  that two programs have not yet been chosen, the process waits for the next press of the button  28  (step  122 ). 
         [0046]    In an alternative embodiment of the invention, instead of pressing the button  28  to choose a program, the wearer presses the button  28  for at least time T 3  to deactivate a non-chosen program. Thus, it will be appreciated that the invention is not limited to the manner in which programs are designated as chosen or not chosen. 
         [0047]    If it is determined at step  130  that two primary acoustical configuration programs have been chosen, then the primary programs that have not been chosen are deactivated (step  132  in  FIG. 3 ). Deactivation in this sense means that the non-chosen programs are made unavailable for selection and execution using the procedure of repeated pressing of the button  28 . Thus, at this point, two primary programs are available for selection and execution. 
         [0048]    After the wearer has used the device  10  for some extended period of time T 4  (step  134 ), such as 80 hours, two secondary acoustical configuration programs are activated for each of the prioritized primary programs. For example, if two primary programs have been chosen by way of the user selection process of steps  124 - 130 , then four secondary programs are activated at step  136 , resulting in a total of six available programs (N=6). Activation of a program in this sense means to make a program available for selection and execution. In a preferred embodiment of the invention, each of the two newly-added secondary programs are variations on a corresponding one of the chosen primary programs. This allows the wearer to make a more refined selection so as to “fine tune” the desired acoustical response. At this point in this example, the wearer has six available programs to evaluate and the user can cycle through the six programs using the button pressing procedure depicted in steps  138 - 152  of  FIG. 3 . This procedure is essentially the same as the procedure of steps  108 - 122  of  FIG. 2 . 
         [0049]    Once the wearer has had a chance to try and compare the six available programs (two primary and four secondary), the wearer can choose the two programs that provide the best performance and deactivate the rest. This is accomplished by pressing the push button  28  for a time T 3 , such as 30 seconds. As shown in  FIG. 3 , if it is determined that the button  28  is pressed for a time T 3  or longer (step  154 ), the processor  16  sets a flag or stores a value indicating that the currently-loaded program has been designated as chosen (step  156 ). At this point, the device  10  generates a distinctive sound (step  158 ) to indicate to the wearer that a program has been chosen. In a preferred embodiment, the device  10  allows the user to choose two of the N number of available programs. However, it will be appreciated that the device  10  could accommodate the choice of more or fewer than two programs. 
         [0050]    If it is determined at step  160  that two programs have not yet been chosen, the process waits for the next press of the button  28  (step  152 ). If it is determined at step  160  that two programs have been chosen, then the other four non-chosen programs are deactivated (step  162  in  FIG. 3 ). At this point, the two best-performing programs as determined by the wearer are available for continued use. (N=2, step  164 .) The wearer can now switch between the two available programs using the button pressing procedure of steps  138 - 152 . 
         [0051]    In some embodiments of the invention, there is no process for activating and choosing secondary acoustical configuration programs. In such embodiments, the wearer chooses some number of best performing primary or secondary programs (such as N=2) and the thereafter the wearer can switch between those chosen programs. This is represented by the dashed line from the box  132  in  FIG. 2  with continuation at step  122 . Thus, in these embodiments, processing does not proceed to step  134  in  FIG. 3 . 
         [0052]    In preferred embodiments of the invention, the programming of the hearing assistance device  10  can be reset to default (factory) conditions by the wearer. In one embodiment, the reset is initiated by pressing the push button  28  for an extended time T 5 , such as two minutes, which is significantly longer than T 3 . In another embodiment, the reset is initiated by closing a battery compartment door while simultaneously pressing the button  28 . This embodiment includes a switch coupled to the battery compartment door, where the status of the switch is provided to the controller  24 . In another embodiment, the reset is initiated by a Dual-Tone Multi-Frequency (DTMF) telephone code received by the telephone coil  30  or microphone  12   a  or  12   b . In yet another embodiment, the reset is initiated by a coded wireless signal received by the wireless interface  32 . In some embodiments, more than one of the above procedures are available for resetting the programming of the device  10 . 
         [0053]    As described above, in preferred embodiments of the invention, a wearer switches between available programs and chooses programs using the manually operated push button  28  mounted on a housing of the device  10 . In alternative embodiments of the invention, the wearer switches between available programs and chooses programs using a wireless remote control device  33 , such as an infrared, radio-frequency or acoustic remote control. In these alternative embodiments, a push button is provided on the remote control device  33 , and the program selection and choosing process proceeds in the same manner as described above except that the wearer uses the push button on the remote control device  33  rather than a button mounted on the housing of the device  10 . In an embodiment including an acoustic remote control, coded acoustic signals, such as a series of clicks in a machine recognizable pattern, may be used to deliver commands to the device  10 . Such acoustic control signals may be received by one or both of the microphones  14   a - 14   b  and provided to the processor  16  for processing. 
         [0054]    In yet another embodiment incorporating voice recognition technology, the wearer switches between available programs and chooses programs by speaking certain “code words” that are received by one or more of the microphones  12   a - 12   b , converted to digital control signals and processed by the processor  16  to control operation of the device  10 . For example, the spoken phrase “switch program” may be interpreted by the processor  16  in the same manner as a push of the button  28  for a time T 2 , and spoken phrase “choose program” may be interpreted by the processor  16  in the same manner as a push of the button  28  for a time T 3 . 
         [0055]      FIGS. 4 and 5  depict a process flow according to another preferred embodiment of the invention wherein the designation of the most effective enhancement programs is based upon a method wherein the wearer of the device evaluates several options for enhancement programs and the device  10  keeps track of how long the wearer uses each program. With this embodiment, the basic assumption is that the program which provides the best performance for the wearer will be the program used most during the evaluation period. As described below, a variation on this embodiment allows the wearer to “override” the time-based designation process and manually choose one or more programs that provide the best performance. This override feature may be provided as an optional operational mode. 
         [0056]    As shown in  FIG. 4 , a first step in the method is to store in memory  26  some number (N) of primary acoustical configuration programs and 2×N number of secondary programs (step  200 ). This step may be performed at the time of manufacture of the hearing assistance device  10  or at a later time, such as during a reprogramming procedure. In a preferred embodiment of the invention, seven primary programs and fourteen secondary programs are loaded into the device memory  26  (N=7, 2×N=14). However, it will be appreciated that any number of programs may be initially loaded into memory  26 , and the invention is not limited to any particular number. In the preferred embodiment of the invention, a feedback canceller algorithm is also stored in the memory  26  of the device  10  at step  200 . 
         [0057]    At some point after the initial programming of the device (step  200 ), a wearer inserts the device  10  into the ear canal (in the case of an ITE device) or places the device  10  behind the ear (in the case of a BTE device) with the associated connection to the ear canal (step  202 ). Once the device  10  is in position, the wearer presses the button  28  for some extended period of time T 1 , such as 60 seconds, to activate the device  10  and initialize the feedback canceller program (step  204 ). According to a preferred embodiment of the invention, the feedback canceller program generates and stores acoustical coefficients that will be applicable to all of the primary and secondary acoustical configuration programs stored in the memory  26 . 
         [0058]    Once the feedback canceller program has performed its initialization procedure, the wearer can cycle through the N number of available primary acoustical configuration programs and try each to determine which provides the best enhancement for the wearer&#39;s hearing loss. The wearer does this by pressing the button  28  for at least some period of time T 2 , such as one second, to switch from one program to the next (step  208 ). For example, a first program may be executed by the processor  16  when the device  10  is first powered on. When the wearer presses the button  28  for at least one second, a second program is executed by the processor  16  (step  220 ). In some embodiments, the device  10  generates two beeps (step  218 ) to indicate to the selection of the second program. When the wearer presses the button  28  again for at least one second, a third program is executed by the processor  16  (step  220 ) and the device  10  generates three beeps to indicate that the third program is selected. This continues until the wearer has cycled through the N number of programs (such as seven). If the wearer presses the button  28  again for at least one second, the first program is loaded again. This process is represented by steps  208 - 228  of  FIG. 4 . To cycle through programs quickly, the wearer may press the button  28  several times consecutively until the desired program is selected. At this point, some number of beeps are generated to indicate which program is selected. 
         [0059]    As with the previously described embodiment, if it is determined that the button  28  is pressed for less than one second (step  210 ), then no new program is loaded for execution and the process waits for the next button press (step  228 ). This prevents inadvertent switching from one program to the next due to an accidental press of the button  28 . 
         [0060]    In the embodiment of  FIG. 4 , a timer circuit is used to time how long each selected primary program is used (step  222 ). The total time of use of each primary program is logged in memory and is continuously updated as the wearer switches from one program to another. After the wearer has used the device  10  for some extended period of time T 5 , such as 80 hours (step  226 ), a calculation is made based on the logged time information to determine which two primary programs have been used most during the T 5  period (step  230 ). The two primary programs having the highest usage time are then designated as chosen (step  232 ) and the remaining primary programs are deactivated (step  234 ). The wearer then uses the device  10  with the two chosen primary programs activated for a period of time T 6 , such as 80 hours (step  236 ). During this time, the wearer can switch between the two programs as desired. 
         [0061]    At the end of the T 6  period, the wearer has used the device  10  for a total time of T 5 +T 6 , such as 160 hours total. At this point, two secondary acoustical configuration programs are activated for each of the two active primary programs, resulting in a total of six available programs (N=6) (step  238 ). In a preferred embodiment of the invention, each of the two newly-added secondary programs is a variation on a corresponding one of the two most-used primary programs. This allows the wearer to make a more refined selection so as to “fine tune” the desired acoustical response. At this point in this example, the wearer has six available programs to evaluate and the wearer can again cycle through the available programs using the button pressing procedure depicted in steps  208 - 228  of  FIG. 4 . 
         [0062]    During the evaluation period of the N number of available primary and related secondary programs, the timer circuit is again used to time how long each program is loaded for use (step  222 ). The total time of use of each program is logged in memory and is continuously updated as the wearer switches from one program to another. After the wearer has used the device  10  for a total period of time T 7  (such as 240 hours, which is significantly greater than the sum of T 5 +T 6 ) (step  224 ), a calculation is made based on the logged time information to determine which two of the N number of available programs have been used most since the secondary programs were activated (step  240 ). The two programs having the highest usage time are then designated as chosen (step  242 ) and the remaining programs are deactivated (step  244 ). At this point, the two most-used programs as determined by the time-logging procedure are available for continued use. (N=2, step  246 .) The wearer can now switch between the two available programs using the button pressing procedure of steps  208 - 228 . 
         [0063]    As mentioned above, a preferred embodiment of the invention allows a wearer to override the time-based selection process and to manually choose one or more programs that provide the best performance for the wearer. This override option is depicted in  FIG. 5  and the dashed box portion of  FIG. 4 . At step  248 , if it is determined that the button  28  is pressed for a time T 3  or longer, such as 30 seconds, the processor  16  sets a flag or stores a value indicating that the currently-loaded program has been designated as chosen (step  250  in  FIG. 5 ). At this point, the device  10  generates a distinctive sound (step  252 ) to indicate to the wearer that a program has been chosen. In a preferred embodiment, the device  10  allows the user to choose two of the available acoustical configuration programs. However, it will be appreciated that the device  10  could accommodate the choice of more or fewer than two acoustical configuration programs. 
         [0064]    If it is determined at step  254  that two primary programs have not yet been chosen, the process waits for the next press of the button  28  (step  228  in  FIG. 4 ). If it is determined at step  254  that two primary programs have been chosen, then the non-chosen primary programs are deactivated (step  256  in  FIG. 5 ). Thus, at this point, two primary programs are available for use. If the wearer has not yet used the device  10  for at least a total period of time T 6  (such as 80 hours) (step  258 ), then processing continues at step  236  of  FIG. 4 . 
         [0065]    After the wearer has used the device  10  for a time T 6  (such as 80 hours) with two primary programs designated as chosen, two secondary programs are activated for each of the two active primary programs, resulting in a total of six available programs (N=6) (step  238 ). At this point in this example, the wearer again has six available programs from which to choose, and the wearer can again cycle through the six available programs using the button pressing procedure depicted in steps  208 - 228  of  FIG. 4 . In this embodiment, the time-logging processing continues as described above unless and until the wearer overrides the procedure by pressing the button  28  for longer than time T 3  (step  248 ). This transfers processing back to step  250  of  FIG. 5  where the processor  16  sets a flag or stores a value indicating that the currently-loaded program has been designated as chosen. Once two programs have been chosen (step  254 ), the non-chosen primary and secondary programs are deactivated (step  256 ), leaving two programs available for selection. 
         [0066]    At this point, the wearer has used the device  10  for at least a total period of time T 6  (such as 80 hours) (step  258 ), so that processing continues at step  246  of  FIG. 4 . Two programs are now available for continued use. These two programs were chosen based on the time-logging procedure, or the override procedure, or a combination of both. The wearer can now switch between the two available programs as desired using the button pressing procedure of steps  208 - 228 . If so desired, the programming of the device  10  may be reset to default conditions as described above using the button  28 , the wireless interface  32  or the telephone coil  30 , as described above. 
         [0067]      FIG. 6  depicts one embodiment of a hearing assistance device  300  for masking tinnitus. The device  300 , which is also referred to herein as a tinnitus masker, includes a digital processor  316  for processing digital audio signals, such as masking stimuli signals. In one preferred embodiment of the invention, the masking stimuli signals comprise narrow-band audio noise. The audio frequencies of these noise signals generally fall into the human audible frequency range, such as in the 20-20,000 Hz band. In one sense, “processing” these masking stimuli signals means accessing digital audio files (such as .wav or .mp3 files) from a digital memory device  326  and “playing” the files to generate corresponding digital audio signals. In another sense, “processing” the masking stimuli signals means to determine which digital audio files to access from memory  326  based on which frequency ranges of narrow-band noise have been designated as chosen. In yet another sense, “processing” the masking stimuli signals means to generate the masking stimuli signals using an audio masking stimuli generator program executed by the processor  316 . In any case, the masking stimuli signals are provided to a D/A converter  318  which converts them to analog audio signals. The analog audio signals at the output of the D/A converter  318  are amplified by an audio amplifier  320  where the level of amplification is controlled by a volume control  334  coupled to a controller  324 . The amplified audio signals at the output of the amplifier  320  are provided to a sound generation device  322 , which may be an audio speaker or other type of transducer that generates sound waves or mechanical vibrations which the user perceives as sound. The amplifier  320  and sound generation device  322  are referred to collectively herein as an audio output section  319  of the device  300 . 
         [0068]    In a preferred embodiment of the invention, the masking stimuli signals comprise narrow-band noise signals. However, it will be appreciated that other types of masking stimuli could be generated according to the invention, including frequency-modulated noise or speech babble noise. Thus, the invention is not limited to any particular type of masking stimuli. 
         [0069]    As shown in  FIG. 6 , a manually operated momentary switch  328 , also referred to herein as a push button  328 , is provided for enabling the user of the device  300  to control various aspects of the operation and programming of the device  300 . The push button  328  is preferably very small and located on an outer surface of a housing associated with the device  300 . In an embodiment wherein the device  300  is worn on or in the ear of the user, the push button  328  is located on a portion of the housing that is accessible to the user while the user is wearing and using the device  300 . For example, the device  300  may be configured as a behind-the-ear (BTE) or in-the-ear (ITE) instrument, with the push button  328  located on an accessible surface of the instruments. In an alternative embodiment of the invention, the wearer switches between available masking stimuli programs and chooses programs using a wireless remote control device  333 , such as an infrared, radio-frequency or acoustic remote control. 
         [0070]    In one alternative embodiment, the tinnitus masking device  300  is disposed in a housing suitable for tabletop use, such as on a bedside table. In this “tabletop” embodiment, the push button  328  and volume control  334  may be located on any surface of the housing that is easily accessible to the user. The sound generation device  322  of this embodiment is preferably a standard audio speaker such as may typically be used in a tabletop clock radio device. It could also have an extension pillow speaker. 
         [0071]    The push button  328  is electrically connected to a controller  324  which generates digital control signals based on the state (open or closed) of the switch of the push button  328 . In a preferred embodiment of the invention, the digital control signals are generated by the controller  324  based on how long the push button  328  is pressed. In this regard, a timer is included in the controller  324  for generating a timing signal to time the duration of the pressing of the button  328 . Further aspects of the operation of the controller  324  and the push button  328  are described in more detail below. 
         [0072]    Nonvolatile memory  326 , such as read-only memory (ROM), programmable ROM (PROM), electrically erasable PROM (EEPROM), or flash memory, is provided for storing programming instructions, digital audio sound files and other operational parameters for the device  300 . Preferably, the memory  326  is accessible by one or both of the processor  316  and the controller  324 . 
         [0073]      FIG. 7  depicts a process flow according to one preferred embodiment of the invention wherein the selection of most effective masking stimulus for tinnitus masking is based upon a “trial and error” interactive and iterative method where the user of the device  300  evaluates several options for noise frequency and chooses a frequency range that provides the best masking experience for the individual user. As shown in  FIG. 7 , a first step in the method is to store in memory various parameters for generating some number (N) of “programs” for generating narrow-band noise using the device  300  (step  350 ). When referring to the operation of the tinnitus masking device  300 , a “program” may refer to various stored commands, values, settings or parameters that are accessed by masking stimuli generation software or firmware to cause the software or firmware to generate masking stimuli within a particular frequency band or masking having particular spectral aspects. In another sense, “program” may refer to a specific digital audio file (.wav, .mp3, etc.) containing masking stimuli, such as audio noise in a particular frequency band or having particular spectral aspects. The step  350  may be performed at the time of manufacture of the device  300  or at a later time, such as during a reprogramming procedure. 
         [0074]    A user of the tinnitus masking device  300  can cycle through N number of available masking stimuli programs and evaluate each to determine which provides the best masking for the user&#39;s tinnitus condition. The user does this by pressing the button  328  for at least some period of time T 2 , such as one second, to switch from one masking program to the next (step  356 ). For example, a first masking program may be activated when the device  300  is first powered on. When the wearer presses the button  328  for at least one second, a second masking program is loaded from memory  326  to the processor  316  and the device  300  generates two beeps (step  366 ) to indicate to the user that the second masking program is loaded. When the wearer presses the button  328  again for at least one second, a third masking program is loaded from memory  326  to the processor  316  and the device  300  generates three beeps to indicate that the third masking program is loaded. This continues until the user has cycled through the N number of masking programs. If the wearer presses the button  328  again for at least five seconds, the first program is loaded for execution again. This process is represented by steps  356 - 370  of  FIG. 7 . 
         [0075]    If it is determined that the button  328  is pressed for less than one second (step  358 ), then no new masking program is loaded and the process waits for the next button press (step  370 ). This prevents inadvertent switching from one masking program to the next due to an accidental press of the button  328 . 
         [0076]    Once the user has had a chance to evaluate all of the available masking stimuli programs, the user may find that some smaller number of the programs, such as one or two, seem to be used the most because they provide the best masking performance for the user in various situations. For example, one of the masking stimuli programs may provide the best masking when the user is trying to sleep. Another of the masking stimuli programs may provide the best masking when the user is trying to concentrate while reading. A preferred embodiment of the invention allows the user to eliminate masking stimuli programs that are not used or rarely used, and to evaluate some additional masking stimuli programs that are variations on the best performing programs. This is accomplished by pressing the push button  328  for a time T 3 , such as 30 seconds, which is longer than the time T 2 , as described below. 
         [0077]    As shown in  FIG. 7 , if it is determined that the button  328  is pressed for a time T 3  or longer (step  372 ), the processor  316  sets a flag or stores a value indicating that the currently-loaded masking stimulus program has been designated as chosen (step  374 ). At this point, the device  300  generates a distinctive sound (step  376 ) to indicate to the user that a preferred masking stimulus program has been chosen. The masking stimuli programs not chosen are then deactivated (step  378 ). Deactivation in this sense means that the non-chosen programs are no longer available for selection using the procedure of repeated pressing of the button  328 . 
         [0078]    After the user has used the device  300  for some extended period of time T 4  (step  380 ), such as 40 hours, the frequency band of the chosen program is “split” to provide two additional masking stimuli programs (step  382 ). In the preferred embodiment of the invention, the two new programs provide masking stimuli in two frequency bands that are sub-bands of the frequency band of the chosen masking stimuli program. For example, in a case where the chosen program provides masking stimuli in the 1000-3000 KHz band, one of the newly activated programs may cover 1000-2000 KHz and the other newly activated program may cover 2000-3000 KHz. At this point, three masking stimuli programs are available for continued use and evaluation (N=3, step  384 ). 
         [0079]    The user can now switch between the three available masking stimuli programs using the button pressing procedure of steps  356 - 370  to decide which of the three provides the best masking performance. As described above, the user designates one of the three masking stimulus programs as chosen by pressing the button  328  for at least the time T 3  (step  372 ). The process steps  374 - 384  are then performed based on the newly-chosen masking stimulus program. This selection procedure may be repeated any number of times to allow the user to “tune in” on the most effective masking stimulus program. 
         [0080]    Once the user is satisfied with a particular masking stimulus program, the user presses the button  328  for a time T 4 , such as 30 seconds (step  386 ), at which point all non-chosen masking stimuli programs are removed or deactivated (step  388 ). From this point forward, the tinnitus masking device  300  operates indefinitely using the one selected masking stimulus program. 
         [0081]    In an alternative embodiment of the invention, instead of pressing the button  328  to choose a masking stimuli program, the wearer presses the button  328  for at least time T 3  to deactivate a non-chosen program. Thus, it will be appreciated that the invention is not limited to the manner in which masking stimuli programs are designated as chosen or not chosen. 
         [0082]    As with the hearing assistance device  10 , the tinnitus masking device  300  may be reset to default (factory) conditions by the user. In one embodiment, the reset is initiated by pressing the push button  328  for an extended time T 5  which is significantly longer than T 4 , such as two minutes. In another embodiment, the reset is initiated by closing the battery compartment while simultaneously pressing the button  328 . In yet another embodiment, the reset is initiated using the wireless remote control device  333 . 
         [0083]    In one alternative embodiment, the invention provides a hearing assistance device which is combination hearing aid and tinnitus masker. This embodiment comprises components as depicted in  FIG. 1 , which include the push button  28  for controlling the selection of hearing aid acoustical configuration programs for the hearing aid function (as described in  FIGS. 2-5 ) and a second push button  328  for controlling the selection of masking stimuli programs for the tinnitus masking function (as described in  FIG. 7 ). Alternatively, a single push button may be used for first programming the hearing aid functions and then programming the tinnitus masking functions. Those skilled in the art will appreciate that the processor  16  and controller  24  may be programmed to implement the hearing aid functions and the tinnitus masking functions simultaneously. 
         [0084]    In some preferred embodiments of the invention, instead of or in addition to using a clock signal to determine elapsed operational time of the hearing assistance device  10  (or tinnitus masking device  300 ), elapsed time is determined based on counting the number of times various events occur during the lifetime of the device. For example, since the battery of a hearing assistance device must be replaced periodically, one can count the number of times the battery is replaced to approximate the elapsed operational time of the device. Also, since hearing assistance devices are typically removed and powered down each evening, one can count the number times a device has been cycled on and off, either by opening the battery compartment or by operating an on/off switch, to approximate the elapsed operational time. 
         [0085]    Various batteries used in hearing assistance devices have operational lifetimes ranging from about 3 days to about 30 days, where the exact lifetime depends on the capacity of the particular battery and the power demand of the hearing assistance device. Accordingly, if the expected lifetime of a particular battery in a particular hearing assistance device is 10 days, and the battery has been replaced three times, then one can estimate that the hearing assistance device has been in use for about 30 days. In a preferred embodiment of the invention, the expected lifetime of the battery is a value that is stored in the memory  26  of the hearing assistance device. This value may be updated depending on the particular model of battery in use and the expected power demand of the particular hearing assistance device. 
         [0086]    As shown in  FIG. 8 , the opening and closing of battery compartment door contacts  42  provide an indication that the battery compartment door has been opened and closed. For example, a set of electrical contacts are provided which are closed when the battery compartment door is closed and open when the compartment door is opened. A door contact detection module  44  monitors the battery compartment contacts  42  and generates an “on” or “high” logic signal when the contacts  42  are open and an “off” or “low” logic signal when the contacts  42  are closed. This logic signal is provided to a counter  40  which is incremented each time the signal goes high. A counter value of n indicates that the battery compartment door has been opened n times, indicating either n number of battery replacements or n number of times that the device has been powered down by opening the battery compartment. The counter value is preferably stored in the nonvolatile memory device  26 . For a typical device (having no separate power on/off switch) that is powered down at the end of each day by opening the battery compartment door, a value n may indicate a total use time of n days. If a device does have a separate on/off switch, and the battery is typically removed only when it is being replaced, a value n may indicate a total use time of n×x days, where x is the expected lifetime of the battery in days. 
         [0087]    As also shown in  FIG. 8 , a voltage level detection module  38  may be provided which monitors the voltage of the battery  36 . The voltage level detection module  38  may generate an “on” or “high” logic signal whenever the battery voltage increases by some number of volts, indicating that an old battery has been replaced with a fresh one. This logic signal is provided to the counter  40  which is incremented each time the signal goes high. Similar to the battery replacement example above, a counter value of n indicates that the battery has been replaced n times, which indicates a total use time of n×x days. 
         [0088]    With continued reference to  FIG. 8 , a momentary on/off switch  48  may be provided to turn the hearing assistance device  10  on and off. For example, the switch  48  may be pressed once to turn the device on and once again to turn the device off. An on/off switch detection module  46  monitors the on/off switch  48  and generates an “on” or “high” logic signal each time the switch  48  is operated. This logic signal is provided to the counter  40  which increments each time the signal goes high. A counter value of n indicates that the device  10  (or the device  300 ) has been cycled on and off n/2 times. For example, if a device is typically turned on and off once per day, a counter value of n indicates the device has been in use for 2 days. 
         [0089]    Accordingly, in each operation depicted in  FIGS. 2-5  and  7  wherein a value for the total elapsed operational time of the device is needed, this time value may be determined based on the counter value generated by the counter  40 . For example, the counter value may be used to determine the time value in step  134  of  FIG. 3 , the time value in step  222  of  FIG. 4 , the time value in step  258  of  FIG. 5 , and the time value in step  380  of  FIG. 7 . 
         [0090]    It will be appreciated that a combination of two or more counter values may be used to calculate an elapsed operational time value. For example, one counter value may keep track of the number of times the battery compartment door contacts have opened/closed and another counter value may keep track of the number of times the battery voltage goes from a low value to a high value. In this example, if one counter value indicates that the battery compartment door has been opened/closed once and the other counter value indicates that the battery voltage has not changed significantly, this may indicate that the battery compartment door was opened to power down the device, but the battery was not replaced. 
         [0091]    In another example, the on/off switch counter value may indicate that the device has been in operation for 30 days, and the battery voltage level counter value may indicate that the device has been in operation for 40 days. In various embodiments, an average of these two time values, the greater of these two time values, or the lesser of these two time values may be selected as the elapsed operational time value. 
         [0092]      FIG. 8  depicts the detection modules  38 ,  44  and  46  and the counter  40  as components of the controller  24 . It will be appreciated that in other embodiments, any or all of these components may be in provided in circuitry which is separate from the controller  24 . 
         [0093]    The foregoing description of preferred embodiments for this invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise form disclosed. Obvious modifications or variations are possible in light of the above teachings. The embodiments are chosen and described in an effort to provide the best illustrations of the principles of the invention and its practical application, and to thereby enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the invention as determined by the appended claims when interpreted in accordance with the breadth to which they are fairly, legally, and equitably entitled.