Systems and methods for tinnitus suppression

Abstract

A method is provided that includes receiving a first signal indicative of a sound in a recipient's environment. The method also includes receiving a second signal indicative of the recipient's perception of the sound. The method also includes determining, in response to the first signal and the second signal, whether the recipient is experiencing tinnitus. The method also includes transmitting a stimulation signal to the recipient's auditory system when the recipient is experiencing tinnitus.

Description

Technical Field

[0001] The present application generally relates to a prosthesis configured to suppress the effects of tinnitus on a recipient of the hearing prosthesis. Background Art

[0002] Hearing loss, which can arise from many different causes, is generally of two types: conductive and / or sensorineural. Conductive hearing loss occurs when the normal mechanical pathways to the outer and / or middle ear are blocked (for example, due to damage to the ossicular chain or the ear canal). Sensorineural hearing loss occurs when the inner ear or the neural pathways from the inner ear to the brain are damaged. Various types of hearing prostheses are widely used to improve the lives of their users. Such devices include, for example, hearing aids, cochlear implants, bone conduction implants, middle ear implants, and electroacoustic devices.

[0003] Individuals with conductive hearing loss typically have some form of residual hearing because the hair cells in the cochlea are not damaged. Therefore, individuals with conductive hearing loss may receive a prosthesis that generates mechanical movement of the cochlear fluid rather than a hearing aid, depending on the type of conductive loss, the degree of hearing loss, and customer preference. Examples of such prostheses include bone conduction devices and direct acoustic stimulators.

[0004] However, in many people with severe hearing loss, the cause of their deafness is sensorineural hearing loss. Those with certain forms of sensorineural hearing loss are unable to obtain adequate benefit from hearing prostheses that generate mechanical movement of the cochlear fluid. These individuals can benefit from implanted hearing prostheses that stimulate the nerve cells of the recipient's auditory system in other ways (e.g., electrical, optical, etc.). Cochlear implants are often recommended when sensorineural hearing loss is caused by the absence or destruction of cochlear hair cells (which convert acoustic signals into nerve impulses). Auditory brainstem stimulators may also be recommended when the recipient experiences sensorineural hearing loss due to damage to the auditory nerve.

[0005] These forms of hearing prostheses that are "mostly implantable," "fully implantable," or "completely implantable" have the advantage of allowing the user to have superior aesthetics, as the recipient is visually indistinguishable during daily activities from an individual who has not received such a device. Such devices also have the further advantage of being generally inherently waterproof, allowing the recipient to shower, swim, etc. without taking any special measures. Examples of such devices include, but are not limited to, the Totally Implantable Cochlear Implant ("TICI"), the Mostly Implantable Cochlear Implant ("MICI"), and the Totally Implantable Cochlear Implant utilizing a Totally Implantable Actuator ("TIA"). Summary of the invention

[0006] In one aspect disclosed herein, a method is provided that includes receiving a first signal indicative of a sound in a recipient's environment. The method also includes receiving a second signal indicative of the recipient's perception of the sound. The method also includes determining, in response to the first signal and the second signal, whether the recipient is experiencing tinnitus. In some embodiments, the method also includes transmitting a stimulation signal to the recipient's auditory system when the recipient is experiencing tinnitus.

[0007] In another aspect disclosed herein, an apparatus is provided that includes a control circuit device configured to receive a sensor signal indicative of a biological response of a recipient. The biological response is associated with the recipient's phantom sound perception. The control circuit device is further configured to generate a control signal at least in part in response to the sensor signal. The apparatus also includes a signal processing circuit device configured to generate a data signal at least in part in response to the control signal. The signal processing circuit device is further configured to transmit the data signal to an actuation component of the hearing prosthesis.

[0008] In yet another aspect disclosed herein, an apparatus is provided that includes a signal processing circuit device configured to receive a transducer signal indicative of sound received by at least one acoustic transducer, the at least one acoustic transducer being worn or implanted in a recipient, and configured to generate a data signal to be provided to at least one actuation component of a hearing prosthesis. The at least one acoustic transducer is worn or implanted in a recipient, the hearing prosthesis being worn or implanted in the recipient. The apparatus also includes a control circuit device configured to monitor a neural response of the recipient and the transducer signal, the data signal, or both the transducer signal and the data signal. The control circuit device is further configured to generate a control signal indicative of a masking contribution to be included in the data signal, the masking contribution being configured to at least partially mask tinnitus being experienced by the recipient. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Embodiments are described herein with reference to the accompanying drawings, in which:

[0010] Figure 1 is a perspective view of an example cochlear implant hearing prosthesis implanted in a recipient according to certain embodiments described herein;

[0011] Figure 2A and Figure 2B schematically illustrates example apparatus according to certain embodiments described herein;

[0012] Figure 3 schematically illustrates example variations of masking contributions of a data signal (i) in the absence of tinnitus and (ii) in the presence of tinnitus;

[0013] Figure 4A and Figure 4Bare flow charts of two example methods according to certain embodiments described herein;

[0014] Figure 5 is a flow chart of another example method for providing closed-loop tracking of cortical responses to changes in the auditory environment according to certain embodiments described herein;

[0015] Figure 6 is a flow chart of another example method of providing closed-loop tracking of cortical responses to controlled changes in a masker according to certain embodiments described herein;

[0016] Figure 7 is a flow chart of another example method for providing closed-loop tracking of cortical response envelopes to account for attentional variations according to certain embodiments described herein; and

[0017] Figure 8 is a flow chart of another example method of modifying tinnitus treatment in response to detected distress (eg, gamma band synchronization) associated with tinnitus in accordance with certain embodiments described herein. DETAILED DESCRIPTION

[0018] Tinnitus is an auditory hallucination process that can be perceived as having various characteristics (e.g., pure tone; narrowband noise; chord) and can be experienced unilaterally or bilaterally. Recipients who perceive tinnitus can experience biological effects that can be detected and / or measured. For example, animal experiments have shown that the degree of behavioral importance of external sounds is correlated with the extension of the representation of their frequency in the primary auditory cortex. In addition, there is sound level-dependent activation in the gamma band of the contralateral auditory cortex, which, while may not be related to tinnitus perception itself, encodes its perceived intensity. In addition, while tinnitus perception has been reported to be associated with the gamma band, there is also a relationship between the intensity of distress and neural modulation in the upper beta band. Therefore, electroencephalographic (EEG) measurements can be used to identify, detect and / or characterize the presence of phantom auditory presentations (e.g., the intensity or amplitude of the phantom auditory presentations).

[0019] Masking has been used previously to treat tinnitus, using a consistent level of auditory or electrical stimulation for treatment. Masking can include: adding a masking stimulus (e.g., a signal) corresponding to the sound (e.g., white noise; music; patterned sounds; low-level sounds; sounds customized based on the recipient's tinnitus characteristics) to the sound from the surrounding auditory environment in order to mask or cover up the phantom sound (e.g., ringing; hissing) caused by the tinnitus. The added sound level can be close to the perceived loudness of the phantom sound or louder than it. Although tinnitus can be partially or completely masked by the added sound, thereby reducing the recipient's perception of the phantom sound, masking does not reduce or eliminate the tinnitus itself. In noisy auditory environments, masking may be easy to achieve, but in quieter auditory environments, the consistent level of auditory stimulation used in masking may be undesirable. In addition, in some cases, the perception of tinnitus is intermittent or variable in amplitude.

[0020] Certain embodiments described herein advantageously provide an automated system and method for adjusting masking stimuli (e.g., modifying the amplitude-frequency distribution, timing profile, duty cycle, and / or spectral content of the masking stimuli; increasing and / or decreasing the amplitude of the masking stimuli; activating and / or deactivating the masking stimuli) without intervention by the recipient and / or medical professional (e.g., in a hands-off manner). Certain embodiments advantageously provide an automated technique for treating tinnitus (e.g., using an active closed-loop configuration) by monitoring one or more predetermined biomarkers (e.g., predetermined characteristics of EEG measurements) that indicate the presence, intensity, and / or other characteristics of auditory hallucinations and responding by adjusting the masking stimuli. For example, the masking stimuli can be delivered to the recipient (i) only when auditory hallucinations are detected, (ii) only at an appropriate level to suppress auditory hallucinations, (iii) only when auditory hallucinations cause distress, (iv) in a manner that does not emphasize pulsatile tinnitus, and / or (v) to mitigate the degree of distress experienced by the recipient.

[0021] Figure 1 is a perspective view of an example cochlear implant hearing prosthesis 100 implanted in a recipient according to certain embodiments described herein. Figure 1 1 is shown as including an implanted stimulator unit 120 (e.g., an actuator) and an external microphone assembly 124 (e.g., a partially implantable cochlear implant). An example hearing prosthesis 100 (e.g., a mostly, fully, or completely implantable cochlear implant) according to certain embodiments described herein may replace Figure 1The externally mounted microphone assembly 124 shown in the figure is associated with a subcutaneous implantable assembly including an acoustic transducer (e.g., a microphone). Such a microphone assembly is configured to be positioned (e.g., during surgery) subcutaneously and on, in, or near a recipient's skull, and in a position that facilitates the microphone assembly to receive acoustic signals once implanted (e.g., in a position between the recipient's skin and skull, above and behind the recipient's ear or in the mastoid region).

[0022] like Figure 1 , the recipient has an outer ear 101, a middle ear 105, and an inner ear 107. In a fully functional ear, the outer ear 101 includes an auricle 110 and an ear canal 102. The auricle 110 collects sound pressure or sound waves 103 and conducts them into and through the ear canal 102. Disposed across the far end of the ear canal 102 is an eardrum 104, which vibrates in response to the sound waves 103. This vibration is coupled to an oval window or foramen ovale 112 through three bones of the middle ear 105 (collectively referred to as ossicles 106, including the malleus 108, the incus 109, and the stapes 111). The bones 108, 109, and 111 of the middle ear 105 serve to filter and amplify the sound waves 103, causing the oval window 112 to sound or vibrate in response to the vibrations of the eardrum 104. This vibration sets up fluid motion waves of peripheral lymph inside the cochlea 140. This fluid movement, in turn, activates tiny hair cells (not shown) inside the cochlea 140. The activation of the hair cells causes appropriate nerve impulses to be generated and transmitted through spiral ganglion cells (not shown) and the auditory nerve 114 to the brain (also not shown), where they are perceived as sound.

[0023] like Figure 1 As shown in , the example hearing prosthesis 100 includes one or more components that are temporarily or permanently implanted in a recipient. Figure 1 1 is shown as having an external component 142 that is attached directly or indirectly to the recipient's body and an internal component 144 that is temporarily or permanently implanted in the recipient (e.g., positioned in a depression of the temporal bone adjacent to the recipient's auricle 110). The external component 142 typically includes one or more sound input elements (e.g., external microphone 124) for detecting sound, a sound processing unit 126 (e.g., housed in a behind-the-ear unit), a power source (not shown), and an external transmitter unit 128. Figure 1In the illustrative embodiment of the invention, the external transmitter unit 128 includes an external coil 130 (e.g., a wire antenna coil including multiple turns of electrically insulated single or multiple strands of platinum or gold wire), and preferably includes a magnet (not shown) affixed directly or indirectly to the external coil 130. The external coil 130 of the external transmitter unit 128 is part of an inductive radio frequency (RF) communication link with the internal component 144. The sound processing unit 126 processes the output of the microphone 124, which is positioned external to the recipient's body, in the depicted embodiment, by the recipient's pinna 110. The sound processing unit 126 generates an encoded signal, sometimes referred to herein as an encoded data signal, which is provided to the external transmitter unit 128 (e.g., via a cable). It should be appreciated that the sound processing unit 126 can utilize digital processing techniques to provide frequency shaping, amplification, compression, and other signal conditioning, including conditioning based on recipient-specific fitting parameters.

[0024] The power source of the external component 142 is configured to provide power to the hearing prosthesis 100, wherein the hearing prosthesis 100 includes a battery (e.g., located in the internal component 144, or positioned in a separate implanted location) that is charged by power provided from the external component 142 (e.g., via a transcutaneous energy transfer link). The transcutaneous energy transfer link is used to transfer power and / or data to the internal component 144 of the hearing prosthesis 100. Various types of energy transfer, such as infrared (IR), electromagnetic, capacitive, and inductive transfer, may be used to transfer power and / or data from the external component 142 to the internal component 144. During operation of the hearing prosthesis 100, the power stored by the rechargeable battery is distributed to various other implanted components as needed.

[0025] The internal component 144 includes an internal receiver unit 132, a stimulator unit 120, and an elongated electrode assembly 118. In some embodiments, the internal receiver unit 132 and the stimulator unit 120 are tightly sealed in a biocompatible housing. The internal receiver unit 132 includes an internal coil 136 (e.g., a wire antenna coil comprising a single or multiple strands of electrically insulated platinum or gold wire with multiple turns), and preferably includes a magnet (also not shown) fixed relative to the internal coil 136. The internal receiver unit 132 and the stimulator unit 120 are tightly sealed in a biocompatible housing and are sometimes collectively referred to as a stimulator / receiver unit. The internal coil 136 receives power and / or data signals from the external coil 130 via a transcutaneous energy transfer link (e.g., an inductive RF link). The stimulator unit 120 generates an electrical stimulation signal based on the data signal and delivers the stimulation signal to the recipient via the elongated electrode assembly 118.

[0026] The elongated electrode assembly 118 has a proximal end connected to the stimulator unit 120 and a distal end implanted in the cochlea 140. The electrode assembly 118 extends from the stimulator unit 120 through the mastoid bone 119 to the cochlea 140. In some embodiments, the electrode assembly 118 can be implanted at least in the basal region 116, and sometimes further. For example, the electrode assembly 118 can extend toward the top of the cochlea 140, referred to as the cochlear apex 134. In some cases, the electrode assembly 118 can be inserted into the cochlea 140 via a cochleostomy 122. In other cases, the cochleostomy can be formed by the round window 121, the oval window 112, the promontory 123, or by the apical turn 147 of the cochlea 140.

[0027] The elongated electrode assembly 118 includes a longitudinally aligned and distally extending array 146 of electrodes or contacts 148 disposed along its length, sometimes referred to herein as electrode or contact array 146. Although the electrode array 146 can be disposed on the electrode assembly 118, in most practical applications, the electrode array 146 is integrated into the electrode assembly 118 (e.g., the electrode array 146 is disposed in the electrode assembly 118). As noted, the stimulator unit 120 generates stimulation signals that are applied by the electrodes 148 to the cochlea 140, thereby stimulating the auditory nerve 114.

[0028] Although Figure 1 The hearing prosthesis 100 is schematically illustrated as utilizing an external component 142 including an external microphone 124, an external sound processing unit 126, and an external power source, but in certain other embodiments, one or more of the microphone 124, the sound processing unit 126, and the power source may be implanted on or in a recipient (e.g., within the internal component 144). For example, the hearing prosthesis 100 may have each of the microphone 124, the sound processing unit 126, and the power source implantable on or in a recipient (e.g., encapsulated within a biocompatible component located subcutaneously), and may be referred to as a totally implantable cochlear implant ("TICI"). For another example, the cochlear implant 100 may have most of the components of a cochlear implant implantable on or in a recipient (e.g., excluding the microphone, which may be an in-ear canal microphone), and may be referred to as a mostly implantable cochlear implant ("MICI").

[0029] Figure 2A and Figure 2BAn example device 200 is schematically illustrated in accordance with certain embodiments described herein. The example device 200 of certain embodiments is configured to treat tinnitus by monitoring one or more predetermined biomarkers (e.g., predetermined characteristics of EEG measurements) that indicate the presence, intensity, and / or other characteristics of auditory hallucinations and responding (e.g., by adjusting a masking stimulus). For example, the device 200 can be configured to automatically and actively adjust the masking stimulus (e.g., modify the amplitude-frequency distribution, timing profile, duty cycle, and / or spectral content of the masking stimulus; increase and / or decrease the amplitude of the masking stimulus; activate and / or deactivate the masking stimulus) in a closed-loop configuration without intervention by the recipient and / or medical professional (e.g., in a hands-off manner). For other examples, the device 200 can be configured to initiate (e.g., trigger) other therapeutic and / or tinnitus suppression actions (e.g., delivery of therapeutic drugs; such as applying neural stimulation to the vagus nerve), to communicate the detected presence of one or more predetermined biomarkers to a component configured to perform other therapeutic and / or tinnitus suppression actions (e.g., delivery of therapeutic drugs; applying neural stimulation, such as applying to the vagus nerve), and / or to communicate the detected presence of one or more predetermined biomarkers to a medical professional (e.g., a caregiver).

[0030] In certain embodiments, the device 200 is a component of an implantable (e.g., fully implantable or partially implantable) or non-implantable hearing prosthesis system, examples of which include, but are not limited to: a cochlear implant system, a bone conduction implant system (e.g., an active bone conduction system; a passive bone conduction system, a transcutaneous bone conduction system; a percutaneous bone conduction system), a hearing aid system, a direct acoustic cochlear implant (DACI) system, a middle ear implant system, a middle ear transducer (MET) system, an electroacoustic implant system, another type of hearing prosthesis system, and / or combinations or variations thereof, or any other suitable hearing prosthesis system with or without one or more external components. For example, U.S. Patent Application Publication No. 2017 / 0347213 discloses a tinnitus relief system in combination with a cochlear implant system compatible with certain embodiments described herein. Embodiments may include any type of hearing prosthesis that may utilize the teachings detailed herein and / or variations thereof.

[0031] Figure 2A and Figure 2BThe device 200 includes a control circuit device 210 (e.g., firmware, software, or a combination of firmware and software) that is configured to receive (e.g., from a biomonitor 220) a sensor signal 222 that indicates a biological response of a recipient (e.g., a predetermined biomarker). The biological response is associated with the recipient's phantom sound perception. The control circuit device 210 is also configured to generate a control signal 212 at least partially in response to the sensor signal 222. The device 200 also includes a signal processing circuit device 230 that is configured to generate a data signal 232 at least partially in response to the control signal 212 and transmit the data signal 232 to an actuation component 240 of a hearing prosthesis (e.g., an implantable stimulator unit 120 of a cochlear implant hearing prosthesis 100). In some embodiments, as Figure 2B As schematically illustrated, control circuitry 210 includes monitoring circuitry 260 , tinnitus analysis circuitry 270 (eg, configured to be operably coupled to cortical measurement component 280 of biomonitor 220 ), and masking circuitry 290 .

[0032] As described herein, by comparing sensor signals 222 indicative of a recipient's biological response with signals indicative of actual sound received by an acoustic transducer 250 worn by the recipient, the control circuitry 210 of certain embodiments is configured to objectively measure tinnitus onset and customize masking signals provided to the recipient to automatically counteract (e.g., reduce) the effects of tinnitus. For example, Figure 2B As schematically illustrated in FIG. 1 , control circuit device 210 is configured to provide active, automated, closed-loop suppression of the effects of tinnitus (e.g., masking as needed, when needed, and at the minimum feasible intensity level without user intervention). In some embodiments, control circuit device 210 is also configured to preemptively counteract the effects of tinnitus even before the recipient perceives the phantom sound (e.g., before the phantom sound becomes loud enough for the recipient to be consciously aware of the phantom sound) and / or before the recipient experiences discomfort due to the phantom sound.

[0033] like Figure 2A and Figure 2BAs schematically illustrated in , the device 200 can also be configured to be operably coupled to at least one acoustic transducer 250 (e.g., at least one microphone). The at least one acoustic transducer 250 is configured to respond to sound received by the at least one acoustic transducer 250 by generating a transducer signal 252 indicative of the sound received by the at least one acoustic transducer 250 and transmitting the transducer signal 252 to the device 200 (e.g., the signal processing circuit device 230). In some embodiments, the at least one acoustic transducer 250 includes one or more microphone assemblies located external to the recipient and / or one or more microphone assemblies implanted on or in the recipient. The teachings and / or variations thereof detailed herein can be utilized with any type of external or implantable microphone arrangement.

[0034] In some embodiments, the device 200 includes a signal processing unit (e.g., external or implantable) of a hearing prosthesis system (e.g., hearing prosthesis 100), which may include at least a portion of the control circuit device 210 and / or the signal processing circuit device 230. For example, the signal processing unit may include a digital signal processor ("DSP") having one or more microprocessors or an application specific integrated circuit device ("ASIC"), which includes one or more portions of the control circuit device 210 (e.g., one or more of the monitoring circuit device 260, the tinnitus analysis circuit device 270, and the masking circuit device 290) and the signal processing circuit device 230. In some embodiments, the control circuit device 210 (e.g., one or more of the monitoring circuit device 260, the tinnitus analysis circuit device 270, and the masking circuit device 290) and / or the signal processing circuit device 230 include at least one processor (e.g., microelectronic circuit device; one or more microprocessors or ASICs) and at least one storage device (e.g., non-volatile memory; flash memory) operably coupled to the at least one processor. In some embodiments, two or more of the monitoring circuitry 260, the tinnitus analysis circuitry 270, and the masking circuitry 290 include the same at least one processor and / or the same at least one memory device. In some embodiments, the control circuitry 210 and the signal processing circuitry 230 include the same at least one processor and / or the same at least one memory device. Although the monitoring circuitry 260, the tinnitus analysis circuitry 270, and the masking circuitry 290 are described herein as separate components that communicate with each other (e.g., via the monitoring signal 262 and the detection signal 272), in some embodiments, two or more of these portions of the control circuitry 210 are integrated with each other and provide the functionality described herein without transmitting at least some signals (e.g., the monitoring signal 262 and the detection signal 272) therebetween.

[0035] In some embodiments, the signal processing circuitry 230 is configured to generate the data signal 232 at least in part in response to the transducer signal 252. The signal processing circuitry 230 of some embodiments includes filtering circuitry and an automatic gain controller (AGC) configured to apply filtering (e.g., adaptive filtering) to the resulting data signal 232. For example, the filtering circuitry may be configured to generate a filtered signal 252 indicative of artifacts, noise, oscillations, instabilities, and / or other unwanted acoustic effects of the transducer, and the AGC may be configured to generate and apply corrections to reduce these unwanted effects in the data signal 232.

[0036] In some embodiments, the actuation assembly 240 is configured to receive and respond to the data signal 232 by generating and providing a stimulation signal to the recipient's auditory system. For example, for a cochlear implant hearing prosthesis, the actuation assembly 240 may include a stimulation unit 120 having an elongated electrode assembly 118 having an array 146 of electrodes 148 disposed along its length and configured to apply the stimulation signal to the cochlea 140, thereby stimulating the auditory nerve 114.

[0037] In some embodiments, monitoring circuitry 260 is configured to receive and monitor data signal 232 from signal processing circuitry 230. In some other embodiments, monitoring circuitry 260 is configured to receive and monitor transducer signal 252 from at least one acoustic transducer 250. In some other embodiments, monitoring circuitry 260 is configured to receive and monitor data signal 232 and transducer signal 252. Monitoring circuitry 260 of some embodiments is configured to monitor data signal 232 and / or transducer signal 252 for one or more characteristics of the auditory environment (e.g., amplitude, frequency, spectral content, and / or noise level) and / or for changes in one or more characteristics to a sufficient degree (e.g., satisfying at least one predetermined condition about at least one predetermined range) to warrant determining whether a recipient is experiencing tinnitus (e.g., determining whether tinnitus is present). For example, monitoring circuit device 260 can be configured to detect whether the auditory environment is loud enough (e.g., a sound level above a predetermined value) so that the recipient is unlikely to perceive any auditory hallucinations to a degree that warrants masking by device 200 and / or detect whether the auditory environment is quiet enough (e.g., a sound level below a predetermined value) so that the recipient is likely to perceive auditory hallucinations to a degree that warrants masking by device 200.

[0038] Monitoring circuitry 260 of certain embodiments is further configured to generate monitoring signal 262 and transmit monitoring signal 262 to tinnitus analysis circuitry 270. In certain embodiments, monitoring signal 262 includes information regarding detected characteristics and / or detected changes in characteristics of the auditory environment that are indicative of potential tinnitus perception of the recipient.

[0039] In certain embodiments, tinnitus analysis circuitry 270 is in operative communication with bio-monitor 220 and is configured to receive sensor signal 222 from bio-monitor 220. Tinnitus analysis circuitry 270 of certain embodiments is configured to transmit a trigger signal to bio-monitor 220 (e.g., initiating measurement of a biological response of the recipient by bio-monitor 220) when monitoring signal 262 indicates that the recipient is potentially experiencing an auditory phantom. In certain embodiments, tinnitus analysis circuitry 270 is further configured to receive and respond to monitoring signal 262 by analyzing sensor signal 222 to determine whether the recipient is experiencing an auditory phantom (e.g., due to tinnitus).

[0040] In some embodiments, the biomonitor 220 includes a cortical measurement component 280 configured to perform electroencephalogram (EEG) measurements and transmit sensor signals 222 (e.g., EEG signals indicative of a recipient's neural response) to the tinnitus analysis circuit device 270. For example, the EEG measurement can be independent of or interleaved with the stimulation of the actuation component 240 and can be used to identify the onset of tinnitus, the amplitude of tinnitus, and / or the level of distress caused by tinnitus. In some embodiments, the EEG measurement is performed by the cortical measurement component 280 using one or more electrodes configured to respond to the electrical activity of the recipient's brain. The cortical measurement component 280 of some embodiments is configured to detect electrical potentials (e.g., spontaneous potentials; evoked potentials associated with stimulus presentation) between at least two electrodes in response to brain electrical activity. The at least two electrodes can be selected from the group consisting of: implanted cochlear extra-electrodes (e.g., subcutaneous electrodes); implanted cochlear intra-electrodes; electrodes on the skin surface of the recipient. For example, EEG potentials can be measured between two or more implanted external cochlear electrodes, between two or more electrodes on the skin surface of a recipient, between one or more implanted external cochlear electrodes and one or more electrodes on the skin surface of a recipient, or between one or more implanted external cochlear electrodes and one or more implanted intracochlear electrodes (e.g., one or more electrodes 148 of electrode array 146 of elongated electrode assembly 118; see, e.g., U.S. Patent Application Publication No. 2015 / 0018699A1).

[0041] In some embodiments, tinnitus analysis circuitry 270 is configured to detect the presence of tinnitus using EEG measurements. For example, at least some cortical responses (e.g., mismatch negativity (MMN) responses and / or P100 responses) to auditory stimuli in a person experiencing tinnitus tend to be suppressed compared to the cortical responses of a person with normal hearing. Without being bound by theory, the presence of tinnitus can make the auditory stimulus less noticeable to the recipient, resulting in a reduced response at the cortical level.

[0042] In some embodiments, cortical measurement component 280 is configured to measure auditory evoked potentials (e.g., potentials associated with auditory stimuli) used by tinnitus analysis circuitry 270 to detect the presence of tinnitus. In some such embodiments, the auditory stimuli are generated by signal processing circuitry 230 in response to control signal 212 from control circuitry 210. For example, control signal 212 may direct signal processing circuitry 230 to change the masking contribution of data signal 232, thereby causing a corresponding change in the stimulation signal generated by actuation component 240 and provided to the recipient's auditory system. Figure 3 Schematically illustrates an example variation of the masking contribution of the data signal 232 (i) in the absence of tinnitus and (ii) in the presence of tinnitus. The variation includes introducing gaps (e.g., relatively short periods of time during which the masking contribution is reduced or zero) in an otherwise constant masking contribution. Figure 3 As schematically illustrated in , the presence of tinnitus reduces the magnitude of the MMN response due to the gap compared to the magnitude of the MMN response due to the gap in the absence of tinnitus. In some embodiments, other changes in masking contributions (e.g., changes in masking spectral components; changes in masking volume) are used as auditory stimuli presented to the recipient.

[0043] In certain embodiments, tinnitus analysis circuitry 270 is further configured to respond to monitoring signal 262 (e.g., indicating auditory stimulation provided to the recipient; indicating a change in the auditory environment) by triggering bio-monitor 220 (e.g., cortical measurement component 280) to generate sensor signal 222 (e.g., one or more cortical measurements) and provide sensor signal 222 to tinnitus analysis circuitry 270. For example, after monitoring circuitry 260 detects an auditory stimulation or a change in the auditory environment (e.g., as expressed in data signal 232), monitoring signal 262 may indicate the auditory stimulation or the change in the auditory environment, and tinnitus analysis circuitry 270 may provide a trigger signal to cortical measurement component 280 to initiate one or more cortical measurements.

[0044] In some embodiments, tinnitus analysis circuitry 270 is further configured to respond to monitoring signal 262 (e.g., indicating auditory stimulation and / or auditory environment changes) and to sensor signal 222 (e.g., indicating a neural response of the recipient) by generating a detection signal 272 indicating the presence or absence of tinnitus (e.g., whether the recipient is experiencing tinnitus; whether the recipient is perceiving phantom sounds that are not from the auditory environment). In some embodiments, detection signal 272 also includes information about one or more characteristics of tinnitus (e.g., amplitude).

[0045] In some embodiments, the masking circuit device 290 is configured to receive the detection signal 272 and generate a control signal 212 transmitted to the signal processing circuit device 230 at least in part in response to the detection signal 272. In some embodiments, the control signal 212 indicates a masking contribution of the data signal 232 to be formed by the signal processing circuit device 230 (e.g., indicating a modification of the masking contribution). The masking contribution of some embodiments is configured to at least partially mask or otherwise counteract the effects of the tinnitus experienced by the recipient (e.g., the level of the masking signal can be close to the perceived loudness of the phantom sound or louder than it). The data signal 232 including the masking contribution is transmitted to the actuation component 240, which is configured to transmit a stimulation signal to the auditory system of the recipient. The stimulation signal is configured to at least partially alleviate (e.g., mask) the recipient's discomfort based on the phantom sound (e.g., at least partially mask the recipient's phantom sound perception; at least partially reduce the effects of the tinnitus experienced by the recipient).

[0046] Figure 4- Figure 8 is a flow chart of various example methods according to certain embodiments described herein. Figure 8 An example method is to refer to Figure 2A and Figure 2B The example device is described in FIG4- Figure 8 The example method may be performed by other structures according to certain embodiments described herein. In certain embodiments, FIG. Figure 8 Only one of the example methods is used, while in some other embodiments, two or more example methods are used in combination with each other.

[0047] Figure 4A and Figure 4Bare flow charts of two example methods 400 according to certain embodiments described herein. In operation block 410, method 400 includes receiving a first signal (e.g., transducer signal 252 received from at least one microphone) indicating sound in a recipient's environment. In operation block 420, method 400 also includes receiving a second signal (e.g., sensor signal 222; EEG signal) indicating the recipient's perception of sound (e.g., indicating brain activity associated with the recipient's perception of sound). In operation block 430, method 400 also includes determining whether the recipient is experiencing tinnitus (e.g., analyzing the presence of tinnitus) in response to the first signal and the second signal. For example, determining whether the recipient is experiencing tinnitus may include identifying a time period in which the first signal indicates silence in the environment (e.g., the sound in the environment is less than a predetermined amplitude) and in which the second signal indicates the recipient's perception of sound (e.g., the sound perception is greater than a predetermined level). This coincidence of a lack of sound in the environment and the recipient's perception of sound may indicate that the recipient is experiencing tinnitus. In operation block 440, Figure 4B The method 400 also includes transmitting a stimulation signal to the recipient's auditory system when the recipient is experiencing tinnitus.

[0048] In some embodiments, method 400 further includes configuring the stimulation signal to provide therapy for tinnitus to the recipient. For example, configuring the stimulation signal may include iteratively adjusting at least a portion of an amplitude-spectrum of the stimulation signal in response to the second signal.

[0049] In some embodiments, receiving the first signal, receiving the second signal, determining whether the recipient is experiencing tinnitus, and transmitting the stimulation signal are automatically performed by the hearing prosthesis. In this way, some embodiments advantageously provide active, closed-loop suppression of the recipient's tinnitus.

[0050] Figure 5Flowchart of another example method 500 for providing closed-loop tracking of cortical responses to changes in an auditory environment according to some embodiments described herein. In operation block 510, method 500 includes receiving an input auditory signal (e.g., transducer signal 252 received from at least one microphone) indicating a sound in a recipient's environment. In operation block 520, method 500 also includes processing and encoding the input auditory signal with a masking signal. For example, the masking signal may correspond to a sound (e.g., white noise; music; patterned sound; sound customized based on the recipient's tinnitus characteristics) to be added to the sound in the recipient's environment to mask or cover up phantom sounds (e.g., ringing; hissing) due to tinnitus. The resulting encoded signal (e.g., data signal 232) has an auditory contribution (e.g., indicating a sound received by at least one microphone) mixed with a masking contribution (e.g., indicating a sound added to mask the phantom sound). In some embodiments, receiving the input auditory signal and processing and encoding the input auditory signal with the masking signal are performed by signal processing circuit device 230.

[0051] At operation block 530, the method 500 further includes transmitting the resulting coded signal (e.g., the data signal 232) to the actuation assembly 240 of the hearing prosthesis worn by the recipient. At operation block 540, the method 500 further includes identifying a change in the auditory environment by monitoring the coded signal for a substantial change (e.g., a change in the amplitude or spectral content of the coded signal greater than or equal to a predetermined level). In some embodiments, identifying a change in the auditory environment is performed by the monitoring circuit device 260 that receives the data signal 232.

[0052] In operation block 550, method 500 also includes measuring the cortical response of the recipient. In some embodiments, one or more cortical measurements are triggered when a substantial change in the auditory environment is detected (e.g., configured to detect one or more MMN responses and / or P100 responses). In some embodiments, a programmable delay is introduced when a substantial change in the auditory environment is detected and before the cortical measurement is initiated, and the programmable delay can be variable between different recipients (e.g., to take into account different processing delays of different recipients for the change). For example, in order to correlate the measured cortical response with the incoming signal, the measured cortical response can be buffered and aligned after the fact, or the measurement can be delayed to the expected time of the event to better (e.g., more easily) associate the cortical response with the input signal. In some embodiments, the programmable delay can limit the amount of cortical measurement data recorded. In some embodiments, the cortical measurements are aggregated with a time-weighted average to reduce the effects of noise. Example averaging schemes may include, but are not limited to:

[0053] epoch mean(n) =α*epoch n+(1-α)*epoch mean(n-1) , where α∈(0,1).

[0054] In certain embodiments, upon detecting a substantial change in the auditory environment (e.g., as expressed in data signal 232), monitoring circuitry 260 may transmit monitoring signal 262 to tinnitus analysis circuitry 270, and measuring the recipient's cortical response may be performed by cortical measurement component 280 under the control of tinnitus analysis circuitry 270, which may receive the cortical measurement (e.g., sensor signal 222).

[0055] In operation block 560, method 500 also includes analyzing cortical measurements for the presence of tinnitus. In some embodiments, the amplitude of at least one cortical response (e.g., one or more MMN responses and / or P100 responses) is compared to a corresponding level or threshold. In some embodiments, the threshold is predetermined (e.g., a previous calibration level or a long-term reference level). In some other embodiments, the threshold is adaptively adjusted. For example, the threshold can be adaptively changed in response to the input / output ratio. For another example, the threshold can also be mediated by a secondary response (e.g., a P100 threshold can be mediated based on the P300 amplitude, or vice versa, because these responses are both attention-mediated, but to different degrees). In some other embodiments, rather than comparing to a corresponding level or threshold, a change in the cortical measurement (as a statistical outlier) can be used as an indication of tinnitus.

[0056] In operation block 570, method 500 further includes updating the masking signal to be mixed with the input auditory signal in operation block 520. Depending on the comparison of at least one cortical response to the corresponding predetermined level, one or more characteristics (e.g., amplitude; spectral content) of the masking signal may be updated to improve the degree of masking of the phantom sound. In some embodiments, analyzing the cortical measurements is performed by tinnitus analysis circuitry 270, which generates a detection signal 272 indicating the presence or absence of tinnitus and transmits the detection signal 272 to masking circuitry 290. In some embodiments, updating the masking signal is performed by masking circuitry 290 in response to the detection signal 272, and masking circuitry 290 generates control signal 212 (e.g., indicating the masking signal to be mixed with the input auditory signal) and transmits the control signal 212 to signal processing circuitry 230.

[0057] Figure 6 is a flow chart of another example method 600 for providing closed-loop tracking of cortical responses to controlled changes in a masker according to certain embodiments described herein. The method 600 includes the method described herein with respect to Figure 5The example method 500 of operation blocks 510-570 is described. In operation block 610, the method 600 also includes controllably changing the masking signal after updating the masking signal in operation block 570. In some embodiments, a predetermined function is used to controllably change the masking signal (e.g., at pseudo-random times when the recipient is in a quiet auditory environment) and the changed masking signal is mixed with the input auditory signal in operation block 520. For example, controllably changing the masking signal may include introducing gaps (e.g., relatively short time periods in which the masking signal is reduced or zero) in an otherwise constant masking signal. In some embodiments, such changes in the masking signal may be accompanied by the triggering of one or more measurements of the cortical response in operation block 550. As Figure 6 As schematically illustrated by delay block 620 of , triggering of one or more cortical response measurements may be performed after a programmable delay corresponding to a known timing when the altered masking signal will be presented to the recipient (e.g., by signal processing circuitry 230 and actuation component 240). In some embodiments, controllably altering the masking signal is performed by masking circuitry 290.

[0058] Figure 7 is a flow chart of another example method 700 for providing closed-loop tracking of cortical response envelopes to account for attentional changes according to certain embodiments described herein. Higher-level cortical response amplitudes (e.g., MMN amplitudes) are attention-dependent (e.g., if the recipient attends to an auditory stimulus, the response amplitude increases). Figure 7 The method 700 is configured to provide an improved level of closed-loop control of tinnitus treatment by correlating EEG responses in the temporal cortex (e.g., envelopes of cortical responses) with auditory signals provided to the recipient that the recipient is paying attention to (e.g., envelopes of delivered audio). In some embodiments, attention behavior is used as a measure of the substantial change in expected cortical responses (e.g., expected cortical MMN responses and / or P100 responses) and delivered auditory output.

[0059] Method 700 includes the following aspects of the present invention: Figure 5 The method 700 includes extracting the envelope of the auditory signal delivered to the recipient at operation block 710 (e.g., performed by the monitoring circuit device 260) and performing the following steps: Figure 7The method 700 may further include extracting an envelope of a measured cortical response (e.g., measured using the cortical measurement component 280 in operation block 550) and providing the extracted envelope for analysis (e.g., providing the extracted envelope to the tinnitus analysis circuit device 270 for analysis) after a programmable delay schematically illustrated in the delay block 720 of the method 700. In operation block 730, the method 700 may further include extracting an envelope of a measured cortical response (e.g., measured using the cortical measurement component 280 in operation block 550) and providing the extracted envelope for analysis (e.g., providing the extracted envelope to the tinnitus analysis circuit device 270 for analysis). Analyzing the presence of tinnitus in operation block 560 may include comparing the extracted envelope of the auditory signal and the extracted envelope of the measured cortical response and identifying correlation of the extracted envelopes. Updating the masking signal in operation block 570 (e.g., performed by the masking circuit device 290) may include using information about the correlated extracted envelope to generate an update of the masking signal to be mixed with the input auditory signal in operation block 520.

[0060] Figure 8 is a flow chart of another example method 800 for modifying tinnitus therapy in response to detected distress (e.g., gamma band synchronization) associated with tinnitus in accordance with certain embodiments described herein. In some cases, if the recipient does not notice the tinnitus and / or is not aggravated by the tinnitus, the presence of tinnitus is not a problem that needs to be treated, and at certain times, the presence of a masking signal may be detrimental to the recipient and / or the overall treatment. In certain embodiments, the example method 800 includes monitoring cortical responses for features (e.g., gamma band synchronization and / or beta band synchronization) associated with distress (e.g., distress associated with tinnitus) and providing a masking signal to the recipient (e.g., applying tinnitus therapy) and / or modifying the masking signal only when the recipient exhibits signs of distress that may be associated with the presence of tinnitus.

[0061] Method 800 includes the following Figure 5 The method 800 may further include performing, in operation block 810, operations 510-530 and 550-570 as described in the example method 500 of . In operation block 810, the method 800 includes extracting information about gamma band synchronization and / or beta band synchronization of the measured cortical response (e.g., provided by the cortical measurement component 580 in operation block 550). The method 800 also includes analyzing, in operation block 560, the presence of tinnitus (e.g., analyzing information for an indication that the recipient is experiencing distress that may be due to tinnitus). For example, operations 560 and 810 may be performed by the tinnitus analysis circuit device 270. The method 800 also includes updating a masking signal in operation block 570 (e.g., performed by the masking circuit device 290), which is to be mixed with the input auditory signal in operation block 520.

[0062] Certain embodiments described herein are configured to detect pulsatile sounds and / or phantom sounds due to pulsatile tinnitus (e.g., corresponding to the recipient's heartbeat) and provide corresponding treatment. For example, biomonitor 220 may also include a heart rate monitor configured to detect the recipient's heartbeat and provide a sensor signal 222 that is used by control circuitry 210 to adjust the temporal characteristics of the masking signal to treat (e.g., mask; cancel) the pulsatile sounds and / or phantom sounds.

[0063] In some embodiments, the biomonitor 220 includes a functional near infrared spectroscopy (fNIRS) monitor configured to detect blood oxygenation using infrared light (e.g., different wavelengths). In some such embodiments, an fNIRS matrix of light sources is located on the skin of the recipient or implanted in or under the skin of the recipient. For example, the fNIRS matrix can be used in place of EEG electrodes. Although fNIRS monitors have some similarities to pulse oximetry sensors, unlike pulse oximetry sensors, fNIRS monitors include multiple light sources, each of which is associated with multiple recipients, allowing the location of the part of the brain where oxygen absorption occurs. Increased oxygen utilization is closely related to brain activity levels, so in some embodiments, fNIRS monitors are used to measure some of the same phenomena as EEG monitors, but with improved spatial resolution and reduced temporal resolution. Although the morphology and time constants of fNIRS signals are different from those of EEG signals, in some embodiments, fNIRS signals are used to identify MMN responses, as well as to track low-frequency brain oscillations, as an alternative to EEG measurements or as an additional supplement to electroencephalogram measurements.

[0064] It should be understood that the embodiments disclosed herein are not mutually exclusive and can be combined with each other in various arrangements.

[0065] The scope of the present invention described and claimed herein is not limited by the specific exemplary embodiments disclosed herein, as these embodiments are intended to be illustrative of several aspects of the present invention rather than limiting. Any equivalent embodiments are intended to fall within the scope of the present invention. In fact, various modifications of the present invention in form and detail, in addition to those shown and described herein, will become apparent to those skilled in the art from the foregoing description. Such modifications are also intended to fall within the scope of the claims. The breadth and scope of the present invention should not be limited by any exemplary embodiments disclosed herein, but should only be limited according to the claims and their equivalents.

Claims

1. A device for tinnitus suppression, configured to: receiving a first signal indicative of a sound in an environment of a recipient; receiving a second signal indicative of a biological response of the recipient associated with phantom sound perception; as well as determining whether the recipient is experiencing tinnitus in response to the first signal and the second signal; When the recipient is experiencing tinnitus, a stimulation signal is transmitted to the recipient's auditory system, the stimulation signal being configured to provide therapy for the tinnitus to the recipient.

2. The apparatus of claim 1, wherein the stimulation signal is configured by iteratively adjusting at least a portion of an amplitude-spectrum of the stimulation signal in response to the second signal.

3. The apparatus of claim 1 or claim 2, wherein receiving the first signal, receiving the second signal, determining whether the recipient is experiencing tinnitus, and transmitting the stimulation signal are performed automatically by a hearing prosthesis.

4. The apparatus according to any one of claims 1 to 3, wherein the first signal is received from at least one microphone.

5. The apparatus according to any one of claims 1 to 4, wherein the second signal is indicative of brain activity of the recipient, the brain activity being associated with the recipient's perception of sound. The apparatus of claim 5 , wherein the second signal comprises an electroencephalogram (EEG) signal.

7. A device for suppressing tinnitus, comprising: A control circuit device is configured to: receiving a sensor signal indicative of a biological response of a recipient, the biological response being associated with a phantom sound perception by the recipient; determining whether the recipient is experiencing tinnitus in response to the sensor signal and a transducer signal from at least one acoustic transducer, the transducer signal being indicative of sounds in the recipient's environment; as well as generating a control signal at least in part in response to the sensor signal; and a signal processing circuit arrangement configured to generate a data signal at least in part in response to the control signal, the signal processing circuit arrangement further configured to transmit the data signal to an actuation assembly of the hearing prosthesis.

8. The device of claim 7, wherein the signal processing circuit device is further configured to receive the transducer signal from at least one acoustic transducer, the transducer signal indicating the sound received by the at least one acoustic transducer, and the signal processing circuit device is further configured to generate the data signal at least partially in response to the transducer signal.

9. The apparatus of claim 8, wherein the control circuitry is further configured to receive the transducer signal and to automatically generate the control signal at least partially in response to the transducer signal.

10. The apparatus of claim 8, wherein the control circuitry is further configured to receive the data signal and to automatically generate the control signal at least in part in response to the data signal.

11. The device according to any one of claims 7 to 10, wherein the biological response comprises a neural response.

12. The apparatus of any one of claims 7 to 11, wherein the actuation assembly is configured to transmit a stimulation signal to the recipient's auditory system, the stimulation signal being configured to at least partially alleviate the recipient's phantom sound-based discomfort.

13. The device of any one of claims 7 to 12, wherein the actuation assembly is configured to transmit a stimulation signal to the auditory system of the recipient, the stimulation signal being configured to at least partially mask the phantom sound perception of the recipient.

14. An apparatus according to any one of claims 7 to 13, wherein the control circuitry and the signal processing circuitry are in a closed loop configuration.

15. A device for suppressing tinnitus, comprising: signal processing circuitry configured to receive transducer signals indicative of sounds in an environment of a recipient and received by at least one acoustic transducer, the at least one acoustic transducer being worn or implanted in the recipient, and configured to generate data signals to be provided to at least one actuation component of a hearing prosthesis being worn or implanted in the recipient; as well as and a control circuit arrangement configured to monitor a sensor signal of a biological response associated with the recipient's phantom sound perception and the transducer signal, the control circuit arrangement being further configured to: determine whether the recipient is experiencing tinnitus in response to the sensor signal and the transducer signal; and generate a control signal indicative of a masking contribution to be included in the data signal, the masking contribution being configured to at least partially mask the tinnitus being experienced by the recipient.

16. The apparatus of claim 15, wherein the signal processing circuitry is further configured to respond to the control signal by modifying the masking contribution of the data signal.

17. An apparatus according to claim 15 or claim 16, wherein the biological response comprises a neural response and the control circuitry is configured to receive an electroencephalogram (EEG) signal indicative of the neural response of the recipient.

18. The apparatus of claim 17, wherein the control circuitry is configured to receive a functional near infrared spectroscopy (fNIRS) signal indicative of the neural response of the recipient.

19. An apparatus according to any one of claims 15 to 18, wherein the control circuit device is further configured to receive a signal from a heart rate monitor, the heart rate monitor being configured to detect a heartbeat of the recipient, and the control circuit is further configured to adjust the temporal characteristics of the masking contribution to mask pulsatile tinnitus being experienced by the recipient.

20. The device according to any one of claims 15 to 19, wherein the control circuit device comprises: monitoring circuitry configured to generate a monitoring signal indicative of one or more characteristics of the recipient's auditory environment and / or changes in the one or more characteristics; an analysis circuit arrangement configured to receive the monitoring signal and a sensor signal indicative of the biological response of the recipient, and configured to generate a detection signal indicative of the tinnitus being experienced by the recipient; as well as A masking circuit arrangement is configured to generate the control signal at least in part in response to the detection signal.

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