WO2011116407A1

WO2011116407A1 - Method and apparatus for use in the treatment of tinnitus

Info

Publication number: WO2011116407A1
Application number: PCT/AU2010/000337
Authority: WO
Inventors: Burkhard K. H. G Franz
Original assignee: Burkhard Franz Pty Ltd
Priority date: 2010-03-24
Filing date: 2010-03-24
Publication date: 2011-09-29

Abstract

Creating an audible therapy track for use in treating a subject suffering tinnitus involves providing one or more suppression frequencies which may be specific to the subject and creating one or more therapy signals each of which contains a suppression frequency component. A plurality of therapy signals is mixed with ambient sounds to form the audible therapy track which is stored in a format suitable for playback on a sound generating device. The total number of therapy signals mixed in the audible therapy track is also stored. Preferably the intensity and/or occurrence and/or duration and/or total number of therapy signals mixed into the audible therapy track is randomised. During treatment, the subject listens to the audible therapy track several times per day and provides score input indicating the number of therapy signals that are heard in the audible therapy track. Randomisation of the therapy signals in the therapy track provides a hearing challenge to the subject.

Description

METHOD AND APPARATUS FOR USE IN THE TREATMENT OF TINNITUS

Field of the invention

This invention relates to a method and apparatus for treating a subject suffering from the condition of tinnitus and to a software product for controlling a processor for the same. It relates particularly but not exclusively to therapy involving use of an audible therapy track containing sound bursts at therapeutic frequencies which are listened to by the subject. The invention also relates to a method and apparatus for generating the audible therapy track, and software for use on a computer device for doing the same.

Background to the invention

Tinnitus is the perception of sound when no external sound is present and is colloquially referred to as "ringing in the ears". However, the sound heard by tinnitus sufferers is not limited to ringing but may also take other forms including hissing, roaring, whistling, chirping or clicking. It is an extremely common disease with an estimated 1 in 5 people in Australia experiencing some degree of tinnitus. In extreme cases sufferers are seriously debilitated.

There are a number of known causes of tinnitus of physiological and biochemical origin. Physiological causes include exposure to loud noise over an extended period of time, injury to the head or whiplash and medical conditions such as otosclerosis and Meniere's disease. Biochemical causes include reactions to certain medications such as ototoxic drugs and allergies. Viral infections can also cause tinnitus. In many patients the cause of tinnitus is not known.

It is widely accepted that the brain's primary auditory cortex is tonotopically organised. That is, neurons in the auditory cortex are organised according to the frequency of sound to which they respond best, forming a "frequency map". Previous studies have demonstrated that in tinnitus sufferers there is a marked shift of the cortical representation of the tinnitus frequency into an area adjacent to the expected tonotopic location (Muhlnickel et al 1. Proc Natl Acad Sci USA. 1998 Aug 18; 95(17):10340-3). In one study a strong positive correlation was found between the subjective strength of the tinnitus and the amount of cortical reorganisation.

To date, various approaches have been adopted to alleviate the symptoms of tinnitus with varying degrees of success. Anti-depressant medication has been utilised to ease discomfort and improve well being for serious tinnitus sufferers. Masking procedures have been used widely. Masking involves overriding the internal or tinnitus noise experienced by the patient with an audible external noise. Such an approach distracts the tinnitus sufferer from the tinnitus noise. Alternative approaches such as chiropractic, naturopathy, acupuncture and vitamin and mineral substances have also been tested with varying degrees of success. However to date, and to the best of the present inventor's knowledge, no reliable treatment for tinnitus is known.

The discussion of the background to the invention included herein including reference to documents, acts, materials, devices, articles and the like is intended to explain the context of the present invention. This is not to be taken as an admission or a suggestion that any of the material referred to was published, known or part of the common general knowledge in Australia as at the priority date of any of the claims.

Summary of the invention

The inventor has discovered that it is possible to achieve therapy-induced reorganisation of the brain in subjects suffering from tinnitus in its various forms and degrees of severity, by use of the present invention. This is achieved by addressing the physiological changes that are believed to have developed in the central auditory pathway of tinnitus sufferers, in which there has been an enlarged representation of auditory neurons sensitive to the tinnitus frequency at the cortical level in the brain's auditory field. The inventor hypothesises that expansion of this representation has occurred at the detriment of neighbouring neurons previously sensitive to frequencies neighbouring the tinnitus frequency, thus causing the brain to perceive the tinnitus frequency as an important signal.

According to various embodiments of the present invention, an aim is to reverse the neuronal under-representation in the central auditory cortex of frequencies neighbouring the tinnitus frequencies. This can be achieved by involving the subject in what may be referred to as "reversal therapy", according to embodiments of the present invention.

Viewed from one aspect, the present invention provides a method for creating an audible therapy track for use in treating a subject suffering tinnitus, including the steps of: providing one or more suppression frequencies; creating one or more therapy signals, each containing a suppression frequency; mixing a plurality of therapy signals with ambient sounds to form the audible therapy track; storing the audible therapy track in a format suitable for playback on a sound generating device such as a loudspeaker or earphones; and storing the number of therapy signals mixed in the audible therapy track. Throughout this description, "treatment" or "therapy" or variations thereof is to be taken as providing permanent or temporary relief of symptoms experienced by the subject when suffering tinnitus, or temporary or permanent removal of the subject's tinnitus sounds.

The therapy signals in the audible therapy track may include one or more of a pure tone sound, a polyphonic sound, a narrow band sound and a wide band sound and may have a duration of e.g. 300 to 650 milliseconds, preferably 400 to 600 milliseconds and more preferably about 500 milliseconds. In one embodiment, the minimum intensity of therapy signals in the audible therapy track is about 5 dB less than the minimum intensity of ambient sounds in the audible therapy track. Thus, when the audible therapy track is listened to at a comfortable loudness level, the quietest of the therapy signals will have a quite low intensity (loudness) and will sometimes not be audible to the subject. The maximum intensity of therapy signals in the audible therapy track may be about 25 dB above the maximum intensity of ambient sounds in the audible therapy track.

As described in more detail below, the intensity of the various therapy signals in the audible therapy track are preferably randomised so that during playback, some therapy signals can be heard by the subject easily, some cannot be heard at all and some are only just audible to the subject. By varying the intensity of the therapy signals varies throughout the track, the signals become more unpredictable so that their detection is a challenge to the subject. Preferably, during creation of the audible therapy track the proportion of therapy signals having a louder intensity vs. a quieter intensity is controlled.

Preferably, the method includes the step of randomising one or more of: therapy signal intensity, duration, bandwidth, spacing between signals and total number of therapy signals in the audible therapy track. Alternatively/additionally the total number of therapy signals mixed in the audible therapy track may be randomised. Randomisation of the therapy signal features may be constrained by one or more parameters selected from the group including but not limited to one or both of a minimum and a maximum therapy signal intensity; one or both of a minimum and a maximum therapy signal spacing; and one or both of a minimum and a maximum therapy signal duration.

Preferably, the one or more suppression frequencies are determined specifically for the subject being treated. In one embodiment, this involves: (a) presenting to the subject a sound of varying frequencies and identification by the subject of the frequency or frequencies that match the subject's tinnitus sound; (b) varying the frequency and intensity of the presented sound until a sound which masks or treats the subject's tinnitus or ameliorates the symptoms of the subject's tinnitus is obtained; and (c) identifying a frequency of the sound in step (b) as a subject-specific suppression frequency. Alternatively, a subject-specific suppression frequency may be ascertained by determining the subject's tinnitus frequency and calculating a subject-specific suppression frequency as one half octave above or one half octave below the subject's tinnitus frequency.

The audible therapy track may be stored in any suitable electronic file format such as e.g. WAV, AVI, FLAC, APE, WavPack, MPEG-3, MPEG-4, WMA and AIFF. In one aspect, the present invention provides storage media storing data representing an audible therapy track created using steps described in the foregoing.

Viewed from another aspect, the present invention provides apparatus for generating an audible therapy track for use in treating a subject suffering tinnitus, the apparatus including: (a) a processor configured to receive one or more suppression frequencies, to access one or more ambient sounds, and to create multiple therapy signals each of which includes at least one suppression frequency; (b) a mixer configured to create the audible therapy track by mixing the multiple therapy signals with the one or more ambient sounds; and (c) a memory bus adapted to transmit data representing the audible therapy track from the processor to a therapy track storage element. It is desirable that various occurrences of the therapy signals in the audible therapy track present a hearing challenge for the subject during playback.

Preferably, the apparatus includes a randomiser configured to randomise the multiple therapy signals by one or more of: signal intensity, signal duration, signal bandwidth, signal spacing and the total number of therapy signals mixed in the audible therapy track. In one embodiment, the randomiser is configurable with parameters limiting the extent of randomisation. These parameters may include but are not limited to: minimum/maximum therapy signal intensity; minimum/maximum therapy signal spacing; and minimum/maximum therapy signal duration and e.g. maximum/minimum number of therapy signals in the track. In one embodiment, the randomiser is configurable to provide proportional control over a number of therapy signals having a louder intensity and/or a number of therapy signals having quieter intensity. Signal intensity may be established e.g. relative to the maximum or minimum intensity of the ambient sounds with which the therapy signals are mixed.

The ambient sounds are preferably tracks of ambient sounds stored in an electronic data file. In one embodiment, the apparatus is configured to access a database of ambient sounds, preferably ambient sound tracks, tracks for creation of the audible therapy track. The database may include e.g. musical tracks, background noise tracks, human voice tracks, animal sound tracks or a combination of the foregoing. The database may be located remotely and accessed via a communication network or it may be directly coupled with or incorporated into the apparatus.

In one embodiment, the apparatus is provided with a communication element configured to transmit data between the processor and one or more remotely located devices such as a host or terminal computer. Thus, the processor and mixer may be provided by a host computer receiving inputs from a remotely located terminal computer. In such arrangement, the audible therapy track may be generated by the host computer and transmitted to a terminal computer, for playback or storage on a storage media.

Viewed from yet another aspect, the present invention provides a method for treating tinnitus in a human subject including the steps of: (a) operating a sound generating device to present to the subject an audible therapy track, the therapy track having multiple therapy signals mixed with ambient sounds; (b) detection by the subject of each therapy signal audible to the subject; (c) scoring the number of therapy signals detected by the subject; and (d) comparing the subject's score with the actual number of therapy signals in the audible therapy track; wherein the therapy signals each include at least one suppression frequency.

A suppression frequency is a frequency of sound at which there is complete or partial suppression of (i.e. relief from) the subject's tinnitus sounds, or a frequency at which suppression is expected to occur. In one embodiment, a suppression frequency used in the treatment method is determined specific to the subject being treated. A subject-specific suppression frequency may be determined by calculating one half octave above or below a tinnitus frequency identified for the subject. Alternatively, a subject-specific suppression frequency may be determined by (i) presenting to the subject a sound of varying frequencies and identification by the subject of the frequency or frequencies that match the subject's tinnitus sound; and (ii) varying the frequency and intensity of the presented sound until a sound which masks or treats the subject's tinnitus or ameliorates the symptoms of the subject's tinnitus is obtained; wherein a frequency of the sound in step (ii) is a subject-specific suppression frequency.

The therapy signals in the audible therapy track may be a pure tone sound, a polyphonic sound or a narrow or wide band sound having one or more frequency components at a suppression frequency. Preferably, the therapy signals are randomly arranged in one or more of intensity, duration, bandwidth, spacing and number of occurrences in the audible therapy track. Preferably, steps (a) to (d) are repeated a number times per day such as e.g. 2 to 4 times per day. The therapy may be administered such that the subject undergoes treatment for longer than 4 weeks, preferably longer than 8 weeks and more preferably 3 months to 6 or 12 months to achieve an improvement in the tinnitus condition.

In one embodiment, the method further includes the step of incentivising the subject to actively participate in the method by providing one or more of a reward when the subject's score improves upon a previous score or is higher than a threshold score (such as e.g. 50%, 60%, 70% or 80%) and/or by providing a penalty when the subject's score decreases from a previous score or is lower than a threshold score (e.g. 50%). A reward may involve a visible, audible or tactile indicator designed to please the subject whereas a penalty may involve providing a visible, audible or tactile output designed to displease the subject. Alternatively, incentivising may involve incorporating the treatment method into a game,

Preferably, the treatment method includes the step of determining the subject's tinnitus sound and where the character of the subject's tinnitus changes after a treatment period, adapting the treatment accordingly, by determining one or more new suppression frequencies and creating a new audible therapy track. The new audible therapy track may be based on a subject-specific suppression frequency ascertained using methods described herein.

Viewed from another aspect still, the present invention provides a software program controlling a processor in communication with a sound generating device, for use in treating tinnitus in a subject. The software program contains instructions for the processor to: (a) cause playback of an audible therapy track on the sound generating device in response to a playback input from the subject; (b) receive a score input from the subject indicative of a number of therapy signals heard by the subject during playback of the therapy track; and (c) store score input by the subject in step (b).

In a preferred embodiment, the software program further includes instructions for the processor to compare the score input with the actual number of therapy signals in the audible therapy track.

According to yet another aspect of the present invention, there is provided apparatus for treating tinnitus in a patient including: (a) an storage element storing data representing one or more audible therapy tracks; (b) a sound generating device for presenting to the subject one or more audible therapy tracks; (c) a user interface adapted to receive playback input and score input from the subject; (d) a score memory configured to store score data based on score input; and (e) a processor configured to access audible therapy track data in the storage element upon receiving a playback input from the subject, and to cause the sound generator to present an audible therapy track to the subject; wherein score data is indicative of the number of therapy signals heard by the subject during playback of a therapy track.

In one embodiment, the apparatus is configured to provide a reward e.g. when the subject's score improves upon a previous score or is higher than threshold score and/or a penalty when the subject's score decreases from a previous score and/or is lower than a threshold score. Providing a reward may involve e.g. providing a visible, audible or tactile indicator designed to please the subject whereas providing a penalty may involve providing e.g. a visible, audible or tactile indicator designed to displease the subject.

In an embodiment, the processor is configurable to provide a reminder to the subject, through the user interface, to listen to a therapy track. The reminder may prompt the subject to listen to a therapy track e.g. at pre-set intervals which may be programmed into the apparatus by the subject. The processor may also be configurable to instruct the subject, through the user interface, in how to use the apparatus. This may involve installation of an instruction module. In various embodiments the apparatus includes a communication interface configured to transmit data between the apparatus and a remote device.

Viewed from yet another aspect, the present invention provides a software program product for use in treating tinnitus in a subject, the software program containing instructions for controlling a computer processor, the software program product including: (a) an assessment module capable of controlling the processor to assess a subject's tinnitus character; (b) a track generating module capable of controlling the processor to generate one or more audible therapy tracks for treating the subject's tinnitus; and (c) a therapy module capable of controlling the processor to administer therapy by playback of an audible therapy track on a sound generating device such as a loudspeaker or headphones in communication with the computer processor and receiving score input from the subject. The software program product may further include an evaluation module capable of evaluating score data and usage data obtained from the subject.

According to still another aspect of the present invention, there is provided a software program for creating an audible therapy track for use in treatment of tinnitus in a subject, the software program including instructions for controlling a computer processor to: (a) receive one more suppression frequencies; (b) create one or more therapy signals, each including a suppression frequency; (c) mix a plurality of therapy signals having components at a received suppression frequency with ambient sounds to form the audible therapy track; (d) store the audible therapy track on storage media in a format suitable for playback on a loudspeaker device or earphones; and (e) store the number of therapy signals mixed in the audible therapy track.

The software program may further include instructions for randomising the therapy signals by one or more of: signal intensity, signal duration, signal bandwidth, spacing between signals and total number of therapy signals in the audible therapy track.

In one embodiment, the software program includes instructions for determining a subject- specific suppression frequency by controlling the processor to: (a) operate a loudspeaker device to present to the subject a sound of varying frequencies and receive an input indicating the frequency or frequencies that match the subject's tinnitus sound; and (b) vary the frequency and intensity of the presented sound until an input is received indicating that the presented sound masks or treats the subject's tinnitus or ameliorates the symptoms of the subject's tinnitus; wherein a frequency of the sound in step (b) is a subject-specific suppression frequency. Alternatively/additionally the software program may include instructions for determining a subject-specific suppression frequency by controlling the processor to: operate a loudspeaker device to present to the subject a sound of varying frequencies and receive a tinnitus frequency input indicating the frequency or frequencies that match the subject's tinnitus sound; and calculate a subject-specific suppression frequency as one half octave above or one half octave below the tinnitus frequency.

Brief Description of the Drawings

The present invention will now be described in greater detail with reference to the accompanying drawings. It is to be understood that the embodiments shown are examples only and are not to be taken as limiting the scope of the invention as defined in the claims appended hereto.

Figure 1 is a flowchart showing steps in a method of creating an audible therapy track for use in treating a subject suffering from tinnitus, according to an embodiment of the invention.

Figure 2 is a schematic drawing of apparatus for generating an audible therapy track for use in treating a subject suffering from tinnitus, according to another embodiment of the invention.

Figure 3 is a flowchart showing steps in a method of treating a subject suffering from tinnitus, according to an embodiment of the invention. Figure 4 is a schematic drawing of apparatus for use in treating tinnitus in a subject, according to another embodiment of the invention.

Figure 5 is a schematic drawing representing an embodiment of the invention for use over a network such as the Internet, a wireless network, local area network (LAN) or the like.

Detailed Description

Referring firstly to Figure 1 , there is shown a flow chart showing steps in a method for creating an audible therapy track for use in treating a subject suffering from the condition of tinnitus. In a step 100, at least one and preferably two tinnitus suppression frequencies, f_s and f_s2 are provided. The tinnitus suppression frequencies may be specific to the subject based on a frequency at which the subject's tinnitus symptoms diminish or are suppressed, or it may be an estimate of a frequency at which suppression (or diminishing) of tinnitus sounds is likely to occur.

A subject-specific suppression frequency may be determined in a number of ways. In some cases, a subject may have two or more suppression frequencies, being sound frequencies at which suppression or at least a degree of relief of the symptoms of tinnitus is achieved.

The subject-specific suppression frequency may be determined using an iterative process. Again, the subject's tinnitus frequency is found through a sound matching process. A pulsed narrow band noise at various frequencies is presented until a match for the subject's tinnitus sound is found. The narrow band noise can be generated by any good quality audiometer. A pulsed signal is used as this enables the tinnitus sufferer to distinguish the presented signal from his/her own indigenous tinnitus sounds. Once the tinnitus frequency has been determined, the intensity of this pulsed tinnitus matching signal is increased until the subject's tinnitus is masked. Thereafter, the intensity of the presented pulsed signal is decreased until tinnitus becomes again audible. Now the frequency of the presented pulsed signal is either increased (searching for the tinnitus suppression frequency around ½ octaves above the tinnitus frequency) or decreased (searching for the suppression frequency ½ octaves below the tinnitus frequency) until the subject indicates that his/her tinnitus has been masked. Then the intensity of the presented pulsed sound is reduced until tinnitus becomes again audible. This is then followed by increasing/decreasing the frequency of the presented pulsed signal until tinnitus is again masked. This procedure is repeated until neither the presented pulsed signal nor the indigenous tinnitus sound can be heard (complete suppression) or the intensity of tinnitus is reduced while the pulsed signal is still audible albeit at a very soft loudness level. Frequencies obtained using this method become the subject-specific suppression frequencies which may be used for reversal therapy according to embodiments of the present invention. It is to be noted that in some cases, it is not possible to identify a subject-specific suppression frequency, particularly where it is difficult for the subject to identify the tinnitus frequency, i.e. the frequency of sounds which correspond to the tinnitus sound suffered by the subject, as might be the case in octave confusion. In these and other circumstances, it can be difficult to fully suppress the tinnitus sounds and thus, to identify the suppression frequency. In such circumstances it may be possible to assume an estimate for the tinnitus frequency. A reasonable estimate can be made e.g. based on the subject's hearing loss. The tinnitus frequency usually is close to the frequency of maximum hearing loss. This could be e.g. 3,000 Hz. Thus, in one embodiment, the suppression frequencies provided may be calculated as one half octave above and below the assumed tinnitus frequency yielding suppression frequencies at 2,250 Hz and 4,500 Hz.

In another embodiment, the subject undergoes assessment to determine their tinnitus frequency, that is the frequency of the "ringing" or tinnitus sounds heard by the subject using sound matching techniques known in the art. Once the subject's tinnitus frequency has been established, the subject-specific suppression frequency can be calculated. The suppression frequency is usually found around ½ octaves above and around ½ octaves below the tinnitus frequency. It is the same for man and women. The suppression frequency might alter from typical values because of e.g. pathology of the inner ear. However, in many cases it is preferred to establish the suppression frequencies using the half octave "rule". Thus, for a subject whose tinnitus frequency is identified as 5,000 Hz, the subject will often experience suppression at 3,750 Hz and/or 7,500 Hz (calculated as 0.75 and 1 .5 times the tinnitus frequency); these are subject-specific suppression frequencies. This rule of thumb is applied when the specific suppression frequencies cannot be determined or when no suppression of tinnitus can be demonstrated.

After obtaining the one or more suppression frequencies, one or more therapy signals are created (step 102) and mixed with ambient sounds (step 106). A therapy signal may be e.g. a pure tone sound, a polyphonic sound, a narrow band sound or a wide band sound, each of which contains at least one frequency component at a suppression frequency identified in step 100. The multiple occurrences may include different signal types e.g. pure tone sounds, polyphonic tones and narrow band noise signals. For a narrow band sound a bandwidth of less than 25% of the centre frequency and more preferably less than 15% of the centre frequency is desirable. A typical bandwidth is about 5% of the centre frequency although narrower bandwidths (e.g. 1 -2%) are contemplated. In some cases it may be necessary to vary the bandwidth from subject to subject e.g. to accommodate for a patient's unreliable hearing. Hearing loss typically occurs at the higher frequencies so the bandwidth for therapy signals containing the higher suppression frequency may be chosen to be wider than the bandwidth of therapy signals including the lower suppression frequency where the subject's hearing is more reliable.

In one embodiment, step 104 involves creating a .wav or similar audio file containing the multiple occurrences of the therapy signal (hereinafter referred to as sound bursts). The .wav file is thus a collection of sound bursts of varying intensity, duration and bandwidth with silent periods interspersed. Preferably these variations are randomised in the .wav file so that the subject is unable to predict during playback when a sound burst will occur, or the number of sound bursts in the audible therapy track.

The .wav file containing the multiple sound bursts is then mixed (step 106) with a .wav (or similar) sound file containing ambient sounds such as music, vocal sounds or environmental sounds to form the audible therapy track. Mixing the sound bursts into ambient sounds in this way disguises them so that during playback, detection by the subject is challenging. The mixed file is then converted to a sound file or other media format suitable for storage on a medium that can be played back through a device used by the subject being treated. Data representing the audible therapy track may be stored in any format appropriate to the storage/playback device. One suitable file format is MP3 although others such as AVI, FLAC, APE, MPEG4, WMA and AIFF are contemplated and others still would be known to a person skilled in the art. The file of data comprising the audible therapy track is stored on a storage medium in a step 108. The storage medium may be a computer hard drive, or other device having memory such as a flash memory, compact disc, mini disc, MP3 player, personal digital assistant (PDA), portable personal computer or the like.

The number of therapy signals mixed into the audible therapy track is stored in step 1 10. The number of occurrences of the therapy signal may be recorded in a text file stored on the same device as the data file representing the audible therapy track or it may be appended to the audible therapy track data file itself, in a data field. Preferably, the stored number indicates the number of bursts provided at a lower suppression frequency separately from the number of sound bursts provided at a higher suppression frequency, although in some embodiments only one suppression frequency will be used and in other embodiments, it may be adequate to store the total number of sound bursts occurring in the audible therapy track, at either suppression frequency. The data field or text file may also include details such as the subject's name or other identification, the date on which the audible therapy track was created and parameters used in the creation of the audible therapy track. These may include but are not limited to: the suppression frequency/frequencies used in the creation of the audible therapy track, the duration (in seconds or minutes) of the track, the minimum and/or maximum intensity of the sound bursts, minimum and/or maximum duration of the sound bursts, minimum and/or maximum period between sound bursts and the sound burst bandwidth. The sound bursts typically have a duration of about 500 milliseconds with a rise time and falloff time of 125 milliseconds. In one embodiment, the parameters include one or more intensity ranges utilised in the generation of the audible therapy track and a proportional control input giving proportional control over sound bursts falling into e.g. a quieter intensity range or a louder intensity range.

In a preferred embodiment, the method includes a randomization step 1 12 in which one or more of the intensity, duration, bandwidth and spacing between sound bursts is varied randomly in the audible therapy track. During the inventive process, the inventor has realised that in order for the method of the invention to be most effective, the auditory task must present a challenge to the subject. That is, when the subject is being treated for tinnitus according to embodiments of the invention, the subject must give their full concentration by active participation in order to identify all or at least most/many of the occurrences of the therapy signal within the audible therapy track.

For further explanation, reference is made now to the flowchart of Figure 3 which shows steps in a method for treating tinnitus in a subject according to embodiments of the present invention. In a step 302, the subject operates a device having a loudspeaker, causing playback of the audible therapy track. In a step 304, the subject listens to the audible therapy track, focusing their hearing for detection of the sound bursts. In a step 306, the subject indicates the number of sound bursts heard during playback of the therapy track. This indication may occur at the conclusion of playback for that track with the subject keeping score while the track is playing. Alternatively, the subject may provide an indication each time a sound burst is heard during playback of the audible therapy track e.g. by pressing a button on a device to register each input. At the conclusion of playback, the total number of sound bursts heard by the subject forms a "score" which, in a step 308 is compared with the actual number of sound bursts in the audible therapy track. Ideally, the score is stored each time a therapy track is listened to by the subject so that the subject's performance over time can be monitored. In order to derive maximum benefit from the tinnitus treatment method, it is best that steps 302-308 are performed at least two to three times daily for a period of four weeks or longer. Experiments to date indicate that audible therapy tracks having a duration of approximately 5-10 minutes are useful in diminishing the subject's tinnitus symptoms, particularly where steps 302 to 308 are performed at least twice daily, over a period of several weeks. However in some experiments to date, there has been little change observed in the character of a subject's tinnitus sounds after a treatment period of four weeks. Thus, treatment according to embodiments of the present invention may be administered over a period of several weeks to several months for greatest effect. To maintain the subject's interest, it is preferred that a number of different audible tracks are generated for a particular subject to ensure each treatment continues to present a challenge, to avoid boredom developing and to ensure ongoing active participation in the therapy by the subject.

In one embodiment, the audible therapy track is created substantially in real time. That is, the sound bursts are randomised and mixed into the ambient sounds immediately before or during playback so that each audible therapy track is unique and listened to by the subject only once. Ambient sounds (e.g. a particular instrumental track) may be used more than once with a new randomised set of sound bursts mixed into the track to ensure that there is no familiarisation with or ability to predict (or remember) the location of the sound bursts in the audible therapy track.

Alternatively/additionally, several different audible therapy tracks can be made available to the subject, so the subject can choose a particular therapy track to listen to. Preferably, the tracks are listened to at a comfortable loudness level. This is achieved by causing playback of the audible therapy track on a loudspeaker or similar device. Earphones or headphones which minimise distraction by environmental sounds are preferred.

Some subjects may require treatment through only one ear e.g. where there is complete deafness in the other ear, or alternatively when tinnitus symptoms are only present in one ear.

Preferably, the character of the subject's tinnitus sounds is assessed periodically (step 314), e.g. every four weeks during therapy since the characteristics of the tinnitus sound heard by the subject can change with time, and should change after a period of treatment according to embodiments of the invention (see examples which follow). Thus, where the character of the subject's tinnitus sound has changed, it may be necessary to obtain a new subject-specific suppression frequency and new therapy tracks generated accordingly. After comparison step 308, where the subject's score is below the actual number of sound bursts in the therapy track (step 310), this may indicate that the subject is fully participating in the therapy by offering total concentration. A high score may indicate a higher likelihood of success but may also indicate that the character of the tinnitus sounds suffered by the subject has changed and/or that the track is no longer challenging the subject. Assessment will reveal whether new audible therapy tracks are required for continued success with therapy.

Thus, where the subject's score is less than the actual number of sound bursts in the therapy track (step 312), it is desirable to ascertain whether the score is within an acceptable range. In one embodiment, an acceptable range is 50% to 70% or up to e.g. 80 %. That is, a score less than 100% indicates that the auditory task of detecting the sound bursts remains a challenge.

If the score is too low, e.g. below 50% of the actual number of bursts, this may be an indication that the subject is actively participating but is having difficulty hearing each occurrence of the therapy signal. Monitoring the subject's performance over time and performing regular assessment (step 314) may reveal a gradual improvement in the score, suggesting that the subject's participation in the therapy is improving and/or the therapy itself is improving. Alternatively, a low score may indicate that the subject is not applying sufficient concentration while listening to the track and is not, therefore hearing each of the therapy signals. Alternatively, a very low score may indicate that the subject's hearing ability is inhibiting the treatment. In this situation, it may be necessary to vary one or more parameters for generation of the audible therapy track, such as the lower limit of the sound burst intensity, to make allowances for deficiencies in the subject's hearing.

Where the subject's score is above 100% the subject is falsely identifying sound bursts (false positives). This might indicate that the subject is detecting the wrong signal and needs to be reassessed.

Referring now to Figure 2, there is shown apparatus 200 for generating an audible therapy track according to an embodiment of the invention. Apparatus 200 includes a processor 202 configured to receive as an input via input device 203 one or more suppression frequencies f_s for use in determining therapy signals mixed into the audible therapy track. A mixer 204 is configured to create the audible therapy track by mixing multiple occurrences of therapy signals (hereinafter sound bursts), each of which includes at least one component at one of the suppression frequencies with an ambient soundtrack. A selection of ambient soundtracks may be stored in a memory or other device in communication with the processor or in a database 800 as illustrated in Figure 2. Ambient sounds in database 800 may be e.g. musical tracks, voice recordings, background noise or the like.

A memory bus 206 is provided for transmission of data representing the audible therapy track from the mixer to a therapy track storage element 700. In one embodiment, the apparatus 200 includes a randomiser 208 which randomises the occurrence of the sound bursts by one or more of intensity (i.e. loudness) duration, bandwidth and spacing between bursts.

In a preferred embodiment, processor 202 is also configured to receive as inputs an identifier for identifying the subject for whom the audible therapy track is being generated and controls for configuring the randomiser. Thus, in one embodiment the randomiser is configurable so that upper/or lower limits on the sound burst intensity, sound burst spacing and sound burst duration can be controlled, e.g. by an audiologist. The randomiser controls may also stipulate whether some or all of the sound bursts are pure tone, polyphonic or narrow/wide band noise and the bandwidth of the therapy signal. In a preferred embodiment, randomiser controls enable a user to control the proportion of sound bursts falling into e.g. a quiet intensity range or a louder intensity range. Thus, one or more intensity ranges may be specified as a randomiser control.

These parameters may be dictated according to the subject's hearing ability, changes in the characteristics of the subject's tinnitus sounds and other factors. By defining these parameters, it becomes easy to generate automatically, a number of different audible therapy tracks for a subject to listen to, each of which may be configured specific to a subject being treated, to improve or ameliorate the tinnitus condition of the subject. It may also be possible to provide as an input to the processor the number of tracks requiring generation, the desired track type (e.g. musical vs. voice vs. background noise) and the desired duration of each track. Experiments to date suggest that a track duration of around 5-10 minutes is satisfactory for most subjects, although other track lengths are contemplated.

The database 800 of ambient sounds with which the sound bursts are mixed may include musical tracks, background noise, human voice tracks, animal soundtracks and the like. Musical tracks may be operatic, rock, instrumental or the like. In each case, it is desirable that the audible therapy track is generated in such a way that the sound bursts are somewhat hidden and the task of identifying each of the sound bursts presents an auditory challenge for the subject so that the subject must concentrate in order to hear each sound burst. The level of concentration required and the hearing challenge presented may be relative to the subject's own abilities and any hearing loss which may be present.

In a preferred embodiment, apparatus 200 further includes communication element 210 which is configured to transmit data between the processor and one or more remotely located devices 360 such as terminal computers (see Figure 5) over a communication network 350 (e.g. the Internet, a Wi-Fi network, local area network or the like).

Figure 5 is a schematic illustration of an embodiment of the invention in which there is a centralised system for generating audible therapy tracks. The system provides a host computer 5200 incorporating the features of apparatus 200 and accessing ambient sounds database 800. Preferably, host computer 5200 also stores a database of the audible therapy tracks generated, and the parameters used to create each track. Host computer 5200 is in communication with terminal computers 560, 561 and 562 through communication network 350 although any number of terminal computers may be connected to host computer 5200 as would be understood by one of skill in the art.

A subject operating a terminal computer e.g. 560 may request from host computer 5200 one or more audible therapy tracks for treating tinnitus. In such an embodiment, a computer program embodied in software operating on host computer 5200 at a location remote from the terminal computer 560 interfaces with the subject for delivery of one or more audible therapy tracks in accordance with embodiments of the present invention. A storage medium such as a compact disc, MP3 device or the like may be accessed by the terminal computer 560, e.g. through a CD-RW drive, a USB port, Wi-Fi connection, Bluetooth connection or the like for storage of one or more audible therapy tracks. Alternatively, a device for administering therapy according to embodiments of the invention (e.g. a purpose built MP3 player device configured to receive and store score input from the user) may be connected to the terminal computer to facilitate storage of the one or more audible therapy tracks thereon.

In another embodiment the one or more audible therapy tracks may be stored on host computer 5200. A computer program embodied in software causes playback of a therapy track by terminal computer 560 upon receiving a playback input from the user; terminal computer 560 behaves as a device for treating tinnitus in accordance with embodiments of the present invention. The software program causing the terminal computer processor to cause playback of a therapy track may be stored on the host computer 5200 which essentially controls the behaviour of terminal computer 560, or on the terminal computer itself. Figure 4 is a schematic illustration of apparatus 400 for treating tinnitus according to an embodiment of the present invention. The apparatus includes a processor 402 controlled by a computer program containing instructions stored in software memory 407. The processor 402 is in communication with input/output interface 409 which receives user inputs from input device 403 and controls output devices such as loudspeaker 412 and visual display 414. Interface 409 permits transmission of data through communication network 350 via communication element 410. The apparatus also includes a therapy track storage element 470 storing data files representing one or audible therapy tracks of the kind created by processor 200 or according to the methods of the present invention.

Interface 409 is configured to receive a playback prompt from a user (e.g. the subject). The playback prompt is received via input device 403 in the form of e.g. a button, switch, touch screen or the like operated by the user. The loudspeaker device 412 is under control of the processor 402 and provides playback of an audible therapy track in accordance with the input. Preferably, a collection of different audible therapy tracks is stored on storage element 470 and part of the user's input is a selection of the track to be played. Alternatively the user may select a track type to be played (e.g. vocal, background noise, instrumental, operatic or the like). Alternatively/additionally, the track to be played may be selected at random by the processor, in response to the playback prompt provided by the user.

Interface 409 also receives score input from the user via the input device 403 indicating the number of therapy signals (sound bursts) mixed into the audible therapy track which are heard by the subject during playback. The score input may be provided by the user at the conclusion of playback by operating a keypad associated with the input device 403, or by repeatedly operating a button or switch until the score, indicating the total number of sound burst occurrences heard by the subject, is reached. Alternatively, an individual score input may be provided each time a sound burst is heard during playback. In the latter embodiment, the processor is configured to calculate the sum total of the individual score inputs. In either case, score data based on the score input is stored in score memory 480 for comparison with the actual number of sounds bursts mixed into the audible therapy track.

In one embodiment, software memory 407 of apparatus 400 contains game instruction elements which are designed to maximise engagement of the subject during operation of the apparatus. The game instruction elements may involve, in one embodiment, presentation of a reward when the subject provides a score input which is e.g. better than a previous score input stored for previous playback of a particular track or e.g. better than a pre-determined threshold score. Further, the game instruction elements may involve presentation of a penalty when the subject provides a score input which is less than a previous score input stored for previous playback of a particular track or e.g. less than a pre-determined threshold score.

In one embodiment, the reward is a reward image and the game instruction elements control processor 402 to cause display device 414 to present the reward image. The reward image may include e.g. a static image or animation designed to please the subject such as e.g. an image of a happy face, trophy, medal or prize; or an animation showing a presentation of a trophy, medal, prize or the like. A penalty image or animation may include e.g. a frowning face, a downward pointing thumb or the like. Other suitable images/animations of the type likely to please/displease the subject may be determined by one skilled in the art.

Alternatively/additionally to presentation of a reward image, the game instruction elements may cause loudspeaker device 412 to present to the subject an audible cue indicating a reward or penalty, i.e. reward or penalty sound. A reward sound may include e.g. the sound of a crowd cheering, polyphonic tones representing the sound "ta-daa" or other sounds (typically reaching crescendo) which are pleasing to the subject. Conversely, a penalty sound may include e.g. the sound of a crowd booing. Other suitable sounds of the type likely to please or displease the subject and which may be used as reward/penalty sounds may be determined by one skilled in the art.

Alternatively/additionally, the game instruction elements may cause miniature motors or vibrational elements within the apparatus 400 to activate, providing haptic feedback as part of a reward or penalty.

It is further contemplated that the game instruction elements may include more involved game play to retain the subject's interest. The game may be akin to a video game of the kind that may be played on a computer console or handheld device. In one gaming embodiment, the therapy signals represent auditory indicators for controlling movement of a character or vehicle in a game. Movements may include turning left or right, accelerating or braking, jumping and the like. The auditory indicators are preferably substantially randomised and may be independent or linked with visible cues displayed on a user interface (i.e. screen) providing the character's view of the game environment to enhance game play.

In one embodiment, apparatus 400 contains an internal clock 416 and internal power supply 490. Software memory 407 further contains instruction elements for automatically reminding a user to operate the apparatus 400 e.g. at pre-designated times during the course of a day. Reminder may be by way of e.g. activation of an alarm through loudspeaker device 412.

In one embodiment, software memory 407 may be upgraded from a remote device such as host computer 5200 or another device in communication with the apparatus via communication network 350. The communication network may include one or more of the Internet or other wide area network (WAN), a local area network (LAN), Wi-Fi network, Bluetooth connection or the like and/or physical connections such as a USB. Software memory upgrades may facilitate new enhancements in the apparatus such as new reward/penalty images, sounds and other cues. Additionally, new audible therapy tracks may be communicated to the storage element 470 from a remote device 5200 in communication with the apparatus.

Similarly, score data, usage data and the like may be transmitted from apparatus 400 through terminal computer 560 over network 350 to the remote device 5200. Score data may be analysed by software on the remote device or an audiologist operating the remote device to re-set parameters for use in the generation of new audible therapy tracks for a particular subject which may subsequently be transmitted from the remote device to the apparatus 400, for use by the subject. In some instances this may obviate the need for a face-to-face audiologist appointment. Preferably, the remote device (e.g. host computer 5200) includes a processor executing a software program containing instructions for a comprehensive tinnitus monitoring, therapy and research program.

In such arrangement, the comprehensive software program includes an assessment module for assessing a subject's tinnitus, a track generating module for generating one or more audible therapy tracks for treating the subject's tinnitus, and optionally for transmitting the audible therapy tracks over the communication network to a terminal computer accessible by the subject. The comprehensive software program also includes a therapy module for administering the therapy (playback of the audible therapy track(s) and receiving score input from the subject) and ideally, also includes an evaluation module for evaluating score data and usage data from the subject. The evaluation module may be used to e.g. conduct research into the aetiology of tinnitus and also the effectiveness of treatment programs involving the methods and apparatus of the present invention. The evaluation module may analyse score and usage data to identify when a subject is due for assessment by the assessment module. Thus, the evaluation module may, together with the assessment module, facilitate ongoing and remote evaluation of the subject's tinnitus condition and remotely adapt the therapy according to changes in the subject's tinnitus condition over time. In one embodiment, the assessment, track generating and evaluation modules provided by the software program operating on the host computer are accessible to the subject through the communication network on a subscriber basis. Confidentiality of the details pertaining to the subject's personal identification, tinnitus condition and treatment is maintained through use of secure login and data transmission protocols as are known in the art. In such arrangement, the subject enrols for participation in the program e.g. when attending an initial consultation with an audiologist, or by accessing an online site provided for that purpose over the Internet or the like. In one embodiment, the subject's enrolment involves payment of a fee. Alternatively, the subject may be required to make incremental payments to an organisation associated with the program e.g. each time one of the assessment, track generation or evaluation modules are accessed by that subject. Payments may be by way of direct debit, credit card, PayPal or the like, using secure payment methods as are known to one skilled in the art.

In one embodiment, the tinnitus therapy apparatus 400 is incorporated into e.g. a personal mobile computer, personal digital assistant, smart phone, iPhone or the like on which a tinnitus therapy software application (therapy module) can be stored. The tinnitus therapy software application may be obtained by purchasing and downloading at a kiosk or installing from an installation CD-ROM although it is preferable that the application is downloaded via communication network 350 from host computer 5200 e.g. through an online portal. Such a portal may be dedicated to audiology, or to the treatment of tinnitus, or may be dedicated to the sale of downloadable applications.

Embodiments of the invention which involve web-based distribution of tinnitus therapy software facilitate remote tracking of results and re-evaluation of the suppression frequencies contained in the therapy signals mixed into the audible therapy tracks. Periodic re-evaluation enables the therapy to be adjusted as the character of the subject's tinnitus changes thereby increasing the effectiveness of therapy. Collection of data at a host computer also facilitates collation and analysis for large numbers of subjects for use e.g. to study the effectiveness of the therapy among particular groups (e.g. elderly vs. young, male vs. female, good vs. poor hearing etc) and more broadly.

Embodiments of the invention will now be described in further detail with reference to the following examples obtained from actual patients. EXAMPLE 1

Subject M1 , a male of age 71 presented with tinnitus frequency of 2,676 Hz. M1 's tinnitus was partially suppressed at 4,288 Hz which is marginally above the expected upper suppression frequency of 4,014 Hz (one half octave above the tinnitus frequency). M1 was treated by periodic playback of an audible therapy sound track containing narrow band therapy signals (sound bursts) centred at 4,014 Hz and 2,007 Hz and having 500 milliseconds duration with 125 milliseconds rise and fall time and a bandwidth of approximately 5% of the suppression frequencies. The subject listened to the track three times per day. At initial assessment M1 had Tinnitus Intensity Index (Til): 5 (0-7); Tinnitus Annoying Index (TIA): 5 (0- 7); Tinnitus Stress Index (TSI): moderate (none, mild, moderate, severe, extreme); Tinnitus Handicap Inventory (THI): moderate (none, mild, moderate, severe, extreme) and Measurement of Depression Scale (MDS): mild (none, mild, moderate, severe, extreme). M1 's tinnitus condition was re-evaluated after 4 weeks and 8 weeks of therapy which involved listening to the audible therapy track.

After 4 weeks M1 had some difficulties hearing the sound bursts containing the lower suppression frequencies. M1 claims to have experienced absolutely no tinnitus sounds for about a day; M1 was waiting for the tinnitus sound to return and it did. M1 experienced this phenomenon a few times. M1 stated that the intensity of his tinnitus sounds also dropped off on numerous occasions. M1 remarked that the effectiveness of the therapy improved when using better quality earphones during playback of the audible therapy track.

After 8 weeks, M1 's tinnitus intensity was decreasing and the periods where no tinnitus sounds were experienced at all were becoming longer. M1 was very happy with his progress with the treatment. After 12 weeks tinnitus is absent most of the time and no longer present at night where it used to interrupt sleep.

EXAMPLE 2

Subject M2, a male of age 67 presented with tinnitus but an estimation of the tinnitus frequency could not be determined; M2 could not be suppressed. A tinnitus frequency estimation of 3,000 Hz was adopted for the purpose of determining the suppression frequencies to be used in the audible therapy track. The suppression frequencies (one half octave above and below the tinnitus frequency) were calculated as 4500 Hz and 2250 Hz. At initial assessment M1 had Til: 3; TAI: 4; TST: moderate; THI: mild; MDS: mild. M2's tinnitus condition was evaluated after 4 weeks, 8 weeks and 12 weeks of therapy which involved listening to the audible therapy track at least three times per day, sometimes more. After 4 weeks M2 described a change in the character of the tinnitus sounds, in which there were fewer noises inside the head than was previously the case when the tinnitus had the character of multiple noises. M2 described the change as if there was a reduction in the number of keys being played on a piano. Tinnitus intensity did not change.

After 8 weeks, M2 described the character of his tinnitus to have changed again from being located all over the head to isolated to the right back temple area. M2 described experiencing only one pitch of tinnitus for short periods of time, usually there were about 4 frequencies experienced, very close together. M2 described a decrease in the intensity of the tinnitus sounds such that he could ignore the them most of the time.

After 12 weeks, M2 described further improvement in his tinnitus condition. M2 described a further reduction in the tinnitus intensity and that there remained only one or 2 frequencies in the tinnitus sounds experienced. Localisation of the sounds was to the back of the head. M2 was very happy with the progress. M2 felt that the intensity of tinnitus was reduced by 60%.

Advantageously, the present invention provides methods and apparatus for treating subjects who experience tinnitus which treatment is believed to address physiological events of the condition. This is an improvement on the commonly adopted "masking" techniques or psychological techniques which serve only to divert attention away from the tinnitus sounds but do nothing to diminish the tinnitus sounds perceived by the patient when masking is removed.

The inventor has observed that through use of the inventive methods and apparatus, the reorganisation of the auditory cortex which occurs with the onset and progression of tinnitus can be reversed. It is believed that this is achieved by re-sensitising the affected neurones, i.e. those in the tonotopic "neighbourhood" of the tinnitus frequency. This is achieved by administering subject-controlled therapy which requires active participation by the subject being treated. In order for treatment to be successful, it must present to the subject an auditory challenge to exploit the plasticity of the brain and re-recruit neurons previously lost to perception of the tinnitus frequency.

Another advantage of the present invention is that the therapy can be personalised by ascertaining subject-specific suppression frequencies and/or by adjusting the intensities of the sound bursts to accommodate for e.g. deficiencies in a subject's hearing. Where the terms "comprise", "comprises", "comprised" or "comprising" are used in this specification (including the claims) they are to be interpreted as specifying the presence of the stated features, integers, steps or components, but not precluding the presence of one or more other features, integers, steps or components or group thereof.

It is to be understood that various modifications, additions and/or alterations may be made to the parts previously described without departing from the ambit of the present invention as defined in the claims appended hereto.

Future patent applications may be filed in Australia or in other countries on the basis of or claiming priority from the present application. It is to be understood that the following claims are not intended to limit the scope of what may be claimed in any such future application. Features may be added to or omitted from the claims at a later date so as to further define or re-define the invention or inventions.

Claims

1 . A method for creating an audible therapy track for use in treating a subject suffering tinnitus, including the steps of:

a. providing one or more suppression frequencies;

b. creating one or more therapy signals, each containing a suppression frequency;

c. mixing a plurality of therapy signals with ambient sounds to form the audible therapy track;

d. storing the audible therapy track in a format suitable for playback on a sound generating device; and

e. storing the number of therapy signals mixed in the audible therapy track.

2. A method for creating an audible therapy track according to claim 1 , including the step of, for the plurality of therapy signals, randomising one or more of: signal intensity, signal duration, signal bandwidth spacing between signals, and the total number of therapy signals in the audible therapy track.

3. A method for creating an audible therapy track according to claim 1 or claim 2, including the step of ascertaining a subject-specific suppression frequency, by:

(a) presenting to the subject a sound of varying frequencies and identification by the subject of the frequency or frequencies that match the subject's tinnitus sound;

(b) varying the frequency and intensity of the presented sound until a sound which masks or treats the subject's tinnitus or ameliorates the symptoms of the subject's tinnitus is obtained; and

(c) identifying a frequency of the sound in step (b) as a subject-specific suppression frequency.

4. A method for creating an audible therapy track according to claim 1 or claim 2, including the step of ascertaining a subject-specific suppression frequency by:

(a) determining the subject's tinnitus frequency; and

(b) calculating a subject-specific suppression frequency as one half octave above or one half octave below the subject's tinnitus frequency.

5. A method for creating an audible therapy track according to any one of the preceding claims, wherein therapy signals in the audible therapy track include one or more of a pure tone sound, a polyphonic sound, a narrow band sound and a wide band sound.

6. A method for creating an audible therapy track according to any one of the preceding claims wherein an therapy signal has a duration of 300 to 650 milliseconds, preferably 400 to 600 milliseconds and more preferably about 500 milliseconds.

7. A method for creating an audible therapy track according to claim 2 or any one of claims 3 to 6 when appended to claim 2, wherein the randomising step is constrained by one or more parameters selected from the group including:

(a) one or both of a minimum and a maximum therapy signal intensity;

(b) one or both of a minimum and a maximum therapy signal spacing; and

(c) one or both of a minimum and a maximum therapy signal duration.

8. A method for creating an audible therapy track according to any one of the preceding claims wherein the plurality of therapy signals have a minimum intensity of about 5 dB below the minimum intensity of ambient sounds in the audible therapy track.

9. A method for creating an audible therapy track according to any one of the preceding claims wherein the plurality of therapy signals have a maximum intensity about 25 dB above the maximum intensity of ambient sounds in the audible therapy track.

10. A method for creating an audible therapy track according to any one of the preceding claims including the step of controlling a proportion of therapy signals having a louder intensity and a proportion of therapy signals having a quieter intensity.

1 1 . A method for creating an audible therapy track according to any one of the preceding claims, wherein the audible therapy track is stored in an electronic file format selected from the group including: WAV, AVI, FLAC, APE, WavPack, MPEG-3, MPEG-4, WMA and AIFF.

12. Storage media storing data representing an audible therapy track created using steps according to the method of any one of the preceding claims.

13. Apparatus for generating an audible therapy track for use in treating a subject suffering tinnitus, the apparatus including:

(a) a processor configured to receive one or more suppression frequencies, to access one or more ambient sounds, and to create multiple therapy signals each of which includes at least one suppression frequency;

(b) a mixer configured to create the audible therapy track by mixing the multiple therapy signals with the one or more ambient sounds; and (c) a memory bus adapted to transmit data representing the audible therapy track from the processor to a therapy track storage element.

14. Apparatus for generating an audible therapy track according to claim 13, including a randomiser configured to randomise the multiple therapy signals by one or more of: signal intensity, signal duration, signal bandwidth, signal spacing and number of signals in the audible therapy track.

15. Apparatus for generating an audible therapy track according to claim 14, wherein the randomiser is configurable with parameters including:

(a) one or both of a minimum and a maximum therapy signal intensity;

(b) one or both of a minimum and a maximum therapy signal spacing; and

(c) one or both of a minimum and a maximum therapy signal duration.

16. Apparatus for generating an audible therapy track according to claim 14 or claim 15 wherein the randomiser is configurable for proportional control over a number of therapy signals having a louder intensity and/or a number of therapy signals having quieter intensity.

17. Apparatus for generating an audible therapy track according to any one of claims 13 to 16, wherein the processor is configured to access a database of ambient sounds including one or more of: musical tracks, background noise tracks, human voice tracks, animal sound tracks or a combination of the foregoing.

18. Apparatus for generating an audible therapy track according to any one of claims 13 to 17, wherein various occurrences of the therapy signal in the audible therapy track are configured to present a hearing challenge for the subject during playback.

19. Apparatus for generating an audible therapy track according to any one of claims 13 to 18, including a communication element configured to transmit data between the processor and one or more remotely located devices.

20. Apparatus for generating an audible therapy track according to claim 19, wherein the processor and mixer are provided by a host computer receiving inputs from a remotely located terminal computer.

21 . Apparatus for generating an audible therapy track according to claim 20, wherein the audible therapy track is generated by the host computer and transmitted for playback or storage on a storage media.

22. A method for treating tinnitus in a human subject including the steps of:

(a) operating a sound generating device to present to the subject an audible therapy track, the therapy track having multiple therapy signals mixed with ambient sounds;

(b) detection by the subject of each therapy signal audible to the subject;

(c) scoring the number of therapy signals detected by the subject; and

(d) comparing the subject's score with the actual number of therapy signals in the audible therapy track

wherein the therapy signals each include at least one suppression frequency.

23. A method for treating tinnitus according to claim 22 wherein steps (a) to (d) are repeated a number times per day.

24. A method for treating tinnitus according to claim 22 or claim 23, wherein a therapy signal is a pure tone sound, a polyphonic sound or a narrow or wide band sound having one or more frequency components at a suppression frequency.

25. A method for treating tinnitus according to any one of claims 22 to 24, wherein a suppression frequency component in a therapy signal is subject-specific and is determined by: calculating one half octave above or below a tinnitus frequency of the subject.

26. A method for treating tinnitus according to any one of claims 22 to 24, wherein a suppression frequency component in a therapy signal is subject-specific and is determined by:

(i) presenting to the subject a sound of varying frequencies and identification by the subject of the frequency or frequencies that match the subject's tinnitus sound;

(ii) varying the frequency and intensity of the presented sound until a sound which masks or treats the subject's tinnitus or ameliorates the symptoms of the subject's tinnitus is obtained; and

(iii) identifying a frequency of the sound in step (ii) as a subject-specific suppression frequency.

27. A method for treating tinnitus according to any one of claims 22 to 26, wherein the therapy signals in the audible therapy track are randomly arranged in one or more of intensity, duration, bandwidth, spacing and number of occurrences in the therapy track.

28. A method for treating tinnitus according to any one of claims 22 to 27, wherein a subject undergoes treatment for longer than 4 weeks, preferably longer than 8 weeks and preferably 3 months to 6 or 12 months.

29. A method for treating tinnitus according to any one of claims 22 to 28, wherein steps (a) to (d) are repeated 2 to 4 times per day.

30. A method for treating tinnitus according to any one of claims 22 to 29, including the step of incentivising the subject to actively participate in the method by providing one or more of:

(a) a reward when the subject's score improves upon a previous score;

(b) a reward when the subject's score is higher than threshold score;

(c) a penalty when the subject's score decreases from a previous score; and

(d) a penalty when the score is lower than a threshold score.

31 . A method for treating tinnitus according to claim 30, wherein providing a reward involves providing a visible, audible or tactile indicator designed to please the subject.

32. A method for treating tinnitus according to claim 30, wherein providing a penalty involves providing a visible, audible or tactile output designed to displease the subject.

33. A method for treating tinnitus according to any one of claims 22 to 32, including the step of determining the subject's tinnitus sound and where the character of the subject's tinnitus changes after a treatment period, determining one or more new suppression frequencies and creating a new audible therapy track.

34. A method for treating tinnitus according to claim 33, wherein the new audible therapy track contains therapy signals containing one or more subject-specific suppression frequencies determined according to the steps of claim 25 or claim 26.

35. A software program controlling a processor in communication with a sound generating device, for use in treating tinnitus in a subject; the software program containing instructions for the processor to: (a) cause playback of an audible therapy track on the sound generating device in response to a playback input from the subject;

(b) receive a score input from the subject indicative of a number of therapy signals heard by the subject during playback of the therapy track; and

(c) store score input by the subject in step (b).

36. A software program according to claim 35, further including instructions for the processor to compare the score input with the actual number of therapy signals in the audible therapy track.

37. Apparatus for treating tinnitus in a patient including:

(a) an storage element storing data representing one or more audible therapy tracks;

(b) a sound generating device for presenting to the subject one or more audible therapy tracks;

(c) a user interface adapted to receive playback input and score input from the subject;

(d) a score memory configured to store score data based on score input; and

(e) a processor configured to access audible therapy track data in the storage element upon receiving a playback input from the subject, and to cause the sound generator to present an audible therapy track to the subject;

wherein score data is indicative of the number of therapy signals heard by the subject during playback of a therapy track.

38. Apparatus for treating tinnitus in a patient according to claim 37, wherein the processor is further configured to provide:

(a) a reward when the subject's score improves upon a previous score;

(b) a reward when the subject's score is higher than threshold score;

(c) a penalty when the subject's score decreases from a previous score; and

(d) a penalty when the score is lower than a threshold score;

wherein providing a reward involves providing a visible, audible or tactile indicator designed to please the subject and providing a penalty involves providing a visible, audible or tactile indicator designed to displease the subject.

39. Apparatus for treating tinnitus in a patient according to claim 37 or claim 38 wherein the processor is configurable to provide a reminder to the subject, through the user interface, to listen to a therapy track.

40. Apparatus for treating tinnitus in a patient according to any one of claims 38 to 39 including: a communication interface configured to transmit data between the apparatus and a remote device.

41 . Apparatus for treating tinnitus in a patient according to any one of claims 37 to 40 wherein the processor is configurable to instruct the subject, through the user interface, in how to use the apparatus.

42. A software program product for use in treating tinnitus in a subject, the software program containing instructions for controlling a computer processor, the software program product including:

(a) an assessment module capable of controlling the processor to assess a subject's tinnitus character;

(b) a track generating module capable of controlling the processor to generate one or more audible therapy tracks for treating the subject's tinnitus; and

(c) a therapy module capable of controlling the processor to administer therapy by playback of an audible therapy track on a sound generating device in communication with the computer processor and receiving score input from the subject.

43. A software program product according to claim 42 further including an evaluation module capable of evaluating score data and usage data obtained from the subject.

44. A software program for creating an audible therapy track for use in treatment of tinnitus in a subject, the software program product including instructions for controlling a computer processor to:

(a) receive one more suppression frequencies;

(b) create one or more therapy signals, each including a suppression frequency;

(c) mix a plurality of therapy signals having components at a received suppression frequency with ambient sounds to form the audible therapy track;

(d) store the audible therapy track on storage media in a format suitable for playback on a loudspeaker device or earphones;

(e) store the number of therapy signals mixed in the audible therapy track.

45. A software program according to claim 44 further including instructions for randomising the therapy signals by one or more of: signal intensity, signal duration, signal bandwidth, spacing between signals and total number of therapy signals mixed in the audible therapy track.

46. A software program according to claim 44 or claim 45 further including instructions for determining a subject-specific suppression frequency by controlling the processor to:

(a) operate a loudspeaker device to present to the subject a sound of varying frequencies and receive an input indicating the frequency or frequencies that match the subject's tinnitus sound; and

(b) vary the frequency and intensity of the presented sound until an input is received indicating that the presented sound masks or treats the subject's tinnitus or ameliorates the symptoms of the subject's tinnitus;

wherein a frequency of the sound in step (b) is a subject-specific suppression frequency.

47. A software program according to claim 44 or claim 45 further including instructions for determining a subject-specific suppression frequency by controlling the processor to:

(a) operate a loudspeaker device to present to the subject a sound of varying frequencies and receive a tinnitus frequency input indicating the frequency or frequencies that match the subject's tinnitus sound; and

(b) calculate a subject-specific suppression frequency as one half octave above or one half octave below the tinnitus frequency.