Patent ID: 12251564

DETAILED DESCRIPTION

Systems and methods for fitting a hearing system to a recipient based on cortical potentials of the recipient are described herein. As mentioned above, hearing recipients may include people suffering from various types of hearing loss and having various degrees of hearing loss, including different types and/or degrees of hearing loss at each ear. Regardless of what type or degree of hearing loss a particular hearing system recipient may have, it may be desirable for a hearing system used by the recipient to be customized for various unique preferences and/or characteristics of the recipient. The process of customizing a hearing system to preferences and characteristics of a recipient may be referred to as “fitting” the hearing system to the recipient, and may be performed in various ways using a variety of tools, tests, and measurements. For example, certain novel systems and methods for fitting a hearing system to a recipient are described herein as performing the fitting based on cortical potentials of the recipient that may be detected using electrodes integrated with an cochlear implant system.

As will be described in more detail below, cortical potentials of the recipient may refer to various types of neurofeedback detectable from the brain of a hearing system recipient. Voluntarily (i.e., as a result of conscious efforts of the recipient) or involuntarily (i.e., as a result of subconscious brain processes of the recipient), the recipient's brain may produce signals (e.g., brain waves, etc.) that may be detected (e.g., as voltages, currents, and/or other types of signals) by various types of electrodes and/or other suitable sensors. In certain examples, stimulation may be applied to the recipient such that cortical potentials are detected as evoked responses to the stimulation. In other examples, it may be useful to monitor cortical potentials without any particular stimulation being applied to evoke a response. Various types of stimulation and cortical potentials that may be evoked thereby will be described in more detail below.

By detecting and analyzing cortical potentials in certain ways, systems and methods described herein allow for hearing systems to be accurately and efficiently fitted to recipients. These systems and methods may significantly improve hearing system technology and provide technical benefits to hearing and fitting systems, while also providing usability benefits and advantages to recipients, caretakers, clinicians, and other users associated with the hearing systems.

As one illustrative benefit, system and methods configured to rely on cortical potentials (e.g., instead of or together with behavioral feedback and/or other types of feedback obtained from the recipient) when performing fitting procedures may lead to fitting parameters that are highly accurate and objective, fitting sessions that are performed more dynamically and flexibly (e.g., including virtual fitting sessions that will be described below), and improvements in recipient hearing and overall hearing system experience. In particular, systems and methods described herein for fitting a hearing system to a recipient based on cortical potentials may lead to desirable outcomes for recipients who may have difficulty in expressing or articulating their subjective experiences. For example, it may be useful to determine how a recipient's brain responds to different stimuli if the recipient is a small child for whom behavioral feedback or conventional peripheral measurements (electrocochleography (“ECochG”), auditory brainstem responses (“ABRs”), etc.) are unreliable. Similarly, systems and methods described herein may provide significant fitting improvements for recipients with disabilities that affect speech or understanding (e.g., such that the recipients have difficulty in providing verbal or other behavioral feedback), as well as for recipients who suffer from auditory neuropathy.

As another illustrative benefit, systems and methods described herein for fitting hearing systems based on cortical potentials may be performed automatically from time to time without needing to be directed or facilitated by a clinician (e.g., including in virtual fitting sessions when the recipient is not present at a clinic). In some examples, accurate fitting parameters may be determined, updated, and/or adjusted without recipients even needing to be consciously aware that fitting procedures are underway. In this way, fitting parameters may be automatically and dynamically determined and optimized for a variety of different contexts and situations. For example, it may be advantageous for certain fitting parameters to be used when a recipient is in a quiet room and exerting a high degree of focus, and for different fitting parameters to be used when the recipient is in a noisy room, or is asleep or experiencing various other circumstances or hearing contexts.

Various specific embodiments will now be described in detail with reference to the figures. It will be understood that the specific embodiments described below are provided as non-limiting examples of how various novel and inventive principles may be applied in various situations. Additionally, it will be understood that other examples not explicitly described herein may also be captured by the scope of the claims set forth below. Systems and methods described herein for fitting a hearing system to a recipient based on cortical potentials of the recipient may provide any of the benefits mentioned above, as well as various additional and/or alternative benefits that will be described and/or made apparent below.

FIG.1shows an illustrative cochlear implant system100configured to be used by a recipient. Cochlear implant system100will be understood to represent one illustrative type of hearing system that may be fitted to a recipient based on cortical potentials in accordance with principles described herein. Additionally, as will be made apparent, cochlear implant system100may further serve as an example of a system configured to perform or facilitate methods described herein for fitting hearing systems based on cortical potentials. For instance, an implementation of cochlear implant system100may be configured to perform and/or facilitate various operations involved in fitting the cochlear implant system itself to a recipient (e.g., by detecting and/or analyzing cortical potentials of the recipient, determining or facilitating the determination of fitting parameters, and so forth).

While cochlear implant systems such as cochlear implant system100will be described in detail as the focus of this disclosure, it will be understood that other types of hearing systems and medical systems may also implement the principles described herein (e.g., taking the place of the cochlear implant system or operating in concert with the cochlear implant system) in certain instances. As one example, hearing aids that do not include an electrode lead configured for implantation into the recipient may be employed in certain implementations (e.g., either for both ears or in one ear of a bimodal system that also includes a cochlear implant system). In other examples, medical systems that are not necessarily associated with improving the recipient's hearing may also employ principles described herein. For instance, systems and methods described herein may be implemented as part of a spinal cord stimulation system, a visual prosthetic system, or any other implantable prosthetic or other medical system as may serve a particular implementation.

As shown inFIG.1, cochlear implant system100includes a cochlear implant102, an electrode lead104physically coupled to cochlear implant102and having an array of electrodes106, and a processing unit108configured to be communicatively coupled to cochlear implant102by way of a communication link110.

The cochlear implant system100shown inFIG.1is unilateral (i.e., associated with only one ear of the recipient). Alternatively, a bilateral configuration of cochlear implant system100may include separate cochlear implants and electrode leads for each ear of the recipient. In the bilateral configuration, processing unit108may be implemented by a single processing unit configured to interface with both cochlear implants or by two separate processing units each configured to interface with a different one of the cochlear implants.

Cochlear implant102may be implemented by any suitable type of implantable stimulator. For example, cochlear implant102may be implemented by an implantable cochlear stimulator. Additionally or alternatively, cochlear implant102may be implemented by a brainstem implant and/or any other type of device that may be implanted within the recipient and configured to apply electrical stimulation to one or more stimulation sites located along an auditory pathway of the recipient.

In some examples, cochlear implant102may be configured to generate electrical stimulation representative of an audio signal processed by processing unit108in accordance with one or more stimulation parameters transmitted to cochlear implant102by processing unit108. Cochlear implant102may be further configured to apply the electrical stimulation to one or more stimulation sites (e.g., one or more intracochlear locations) within the recipient by way of one or more electrodes106on electrode lead104. In some examples, cochlear implant102may include a plurality of independent current sources each associated with a channel defined by one or more of electrodes106. In this manner, different stimulation current levels may be applied to multiple stimulation sites simultaneously by way of multiple electrodes106.

Cochlear implant102may additionally or alternatively be configured to generate, store, and/or transmit data. For example, cochlear implant102may use one or more electrodes106to record one or more signals (e.g., one or more voltages, impedances, evoked responses within the recipient, and/or other measurements) and transmit, by way of communication link110, data representative of the one or more signals to processing unit108. In some examples, this data is referred to as back telemetry data.

Electrode lead104may be implemented in any suitable manner. For example, a distal portion of electrode lead104may be pre-curved such that electrode lead104conforms with the helical shape of the cochlea after being implanted. Electrode lead104may alternatively be naturally straight or of any other suitable configuration.

In some examples, electrode lead104includes a plurality of wires (e.g., within an outer sheath) that conductively couple electrodes106to one or more current sources within cochlear implant102. For example, if there are N electrodes106on electrode lead104and n current sources within cochlear implant102, there may be N separate wires within electrode lead104that are configured to conductively connect each electrode106to a different one of the N current sources. It will be understood that, as used herein, “N” may be used as a placeholder value (e.g., an integer1or greater) to generically relate the number of various different types of items described herein. As such, an N used to describe the number of one type of item herein may be different than an N used to describe the number of another item herein. In this case, the number N of electrodes may be 8, 12, 16, or any other suitable number.

Electrodes106are located on at least a distal portion of electrode lead104. In this configuration, after the distal portion of electrode lead104is inserted into the cochlea, electrical stimulation may be applied by way of one or more of electrodes106to one or more intracochlear locations. One or more other electrodes (e.g., including a ground electrode, not explicitly shown) may also be disposed on other parts of electrode lead104(e.g., on a proximal portion of electrode lead104) to, for example, provide a current return path for stimulation current applied by electrodes106and to remain external to the cochlea after the distal portion of electrode lead104is inserted into the cochlea. Additionally or alternatively, a housing of cochlear implant102may serve as a ground for stimulation current applied by electrodes106.

Processing unit108may be configured to interface with (e.g., control and/or receive data from) cochlear implant102. For example, processing unit108may transmit commands (e.g., stimulation parameters and/or other types of operating parameters in the form of data words included in a forward telemetry sequence) to cochlear implant102by way of communication link110. Processing unit108may additionally or alternatively provide operating power to cochlear implant102by transmitting one or more power signals to cochlear implant102by way of communication link110. Processing unit108may additionally or alternatively receive data (e.g., in a backward telemetry sequence) from cochlear implant102by way of communication link110. Communication link110may be implemented by any suitable number of wired and/or wireless bidirectional and/or unidirectional links.

As shown, processing unit108includes a memory112and a processor114configured to be selectively and communicatively coupled to one another. In some examples, memory112and processor114may be distributed between multiple devices and/or multiple locations as may serve a particular implementation.

Memory112may be implemented by any suitable non-transitory computer-readable (e.g., processor-readable) medium such as any combination of non-volatile storage media and/or volatile storage media. Examples of non-volatile storage media may include read-only memory, flash memory, a solid-state drive, a magnetic storage device (e.g., a hard drive), ferroelectric random-access memory (“RAM”), an optical disc, and so forth. Examples of volatile storage media may include RAM (e.g., dynamic RAM) or other types of volatile memory.

Memory112may maintain (e.g., store) executable data used by processor114to perform one or more of the operations described herein. For example, memory112may store instructions116that may be executed by processor114to perform any of the operations described herein. Instructions116may be implemented by any suitable application, program (e.g., sound processing program), software, script, code, and/or other executable data instance. Memory112may also maintain any data received, generated, managed, used, and/or transmitted by processor114.

Processor114may be configured to perform (e.g., execute instructions116stored in memory112to perform) various operations with respect to cochlear implant102. For instance, processor114may perform any of the operations described herein as being performed by processing unit108, including directing operations performed by cochlear implant102. As one illustrative operation, processor114may receive an audio signal (e.g., by way of a microphone communicatively coupled to processing unit108, a wireless interface (e.g., a Bluetooth interface), and/or a wired interface (e.g., an auxiliary input port)). Processor114may process the audio signal in accordance with a sound processing program (e.g., a sound processing program stored in memory112) to generate appropriate stimulation parameters. Processor114may then transmit the stimulation parameters to cochlear implant102to direct cochlear implant102to apply electrical stimulation representative of the audio signal to the recipient.

In some implementations, processor114may also be configured to apply acoustic stimulation to the recipient. For example, cochlear implant system100may be implemented as an electroacoustic hearing system that includes, together with electrode lead104for applying electrical stimulation to the recipient, a loudspeaker (also referred to as a receiver) that is optionally coupled to processing unit108for delivering acoustic stimulation to the recipient. The acoustic stimulation may be representative of an audio signal (e.g., an amplified version of the audio signal), and may be configured to produce sound at frequencies that the recipient retains an ability to hear and, in certain examples as will be described in more detail below, to produce acoustic stimulation that may elicit an evoked response (e.g., a cortical potential) within the recipient.

Processor114may be additionally or alternatively configured to receive and process data generated by cochlear implant102. For example, processor114may receive data representative of a signal recorded by cochlear implant102using one or more electrodes106and, based on the data, adjust one or more operating parameters of processing unit108. Additionally or alternatively, processor114may use the data to perform one or more diagnostic operations with respect to cochlear implant102and/or the recipient.

Other operations may be performed by processor114as may serve a particular implementation. In the description provided herein, any references to operations performed by processing unit108and/or any implementation thereof may be understood to be performed by processor114based on instructions116stored in memory112.

Processing unit108may be implemented by one or more devices configured to interface with cochlear implant102. To illustrate,FIG.2shows an illustrative implementation200of cochlear implant system100in which processing unit108is implemented by a sound processor202configured to be located external to the recipient. In configuration200, sound processor202is communicatively coupled to a microphone204and to a headpiece206that are both configured to be located external to the recipient.

Sound processor202may be implemented by any suitable device that may be worn or carried by the recipient. For example, sound processor202may be implemented by a behind-the-ear (“BTE”) unit configured to be worn behind and/or on top of an ear of the recipient. As another example, sound processor202may be implemented by an off-the-ear unit (also referred to as a body worn device) configured to be worn or carried by the recipient away from the ear. In yet another example, at least a portion of sound processor202may be implemented by circuitry implemented within headpiece206.

Microphone204is configured to detect one or more audio signals (e.g., signals including speech and/or any other type of sound) in an environment of the recipient. Microphone204may be implemented in any suitable manner. For example, microphone204may be implemented by a microphone that is configured to be placed within the concha of the ear near the entrance to the ear canal, such as a T-MIC™ microphone from Advanced Bionics. Such a microphone may be held within the concha of the ear near the entrance of the ear canal during normal operation by a boom or stalk that is attached to an ear hook configured to be selectively attached to sound processor202. Additionally or alternatively, microphone204may be implemented by one or more microphones in or on headpiece206, one or more microphones in or on a housing of sound processor202, one or more beam-forming microphones, and/or any other suitable microphone or set of microphones as may serve a particular implementation.

Headpiece206may be selectively and communicatively coupled to sound processor202by way of a communication link208, which may be implemented by a cable or any other suitable wired or wireless communication link as may serve a particular implementation. Headpiece206may include an external antenna (e.g., a coil and/or one or more wireless communication components) configured to facilitate selective wireless coupling of sound processor202to cochlear implant102. Headpiece206may additionally or alternatively be used to selectively and wirelessly couple any other external device to cochlear implant102. To this end, headpiece206may be configured to be affixed to the recipient's head and positioned such that the external antenna housed within headpiece206is communicatively coupled (e.g., by way of an inductive link) to a corresponding implantable antenna such as an implanted coil (and/or one or more other wireless communication components) associated with cochlear implant102. In this manner, stimulation parameters and/or power signals may be wirelessly and transcutaneously transmitted between sound processor202and cochlear implant102by way of a wireless and transcutaneous communication link210.

In configuration200, sound processor202may receive an audio signal detected by microphone204by receiving a signal (e.g., an electrical signal) representative of the audio signal from microphone204. Sound processor202may additionally or alternatively receive the audio signal by way of any other suitable interface as described herein. Sound processor202may process the audio signal in any of the ways described herein and transmit, by way of headpiece206, stimulation parameters to cochlear implant102to direct cochlear implant102to apply electrical stimulation representative of the audio signal to the recipient.

In an alternative configuration, sound processor202may be implanted within the recipient instead of being located external to the recipient. In this alternative configuration, which may be referred to as a fully implantable configuration of cochlear implant system100, sound processor202and cochlear implant102may be combined into a single device or implemented as separate devices configured to communicate one with another by way of a wired and/or wireless communication link. In a fully implantable implementation of cochlear implant system100, headpiece206may not be included and microphone204may be implemented by one or more microphones implanted within the recipient, located within an ear canal of the recipient, and/or located external to the recipient.

FIG.3shows an illustrative implementation300of cochlear implant system100in which processing unit108is implemented by a combination of sound processor202and a computing device302configured to communicatively couple to sound processor202by way of a communication link304, which may be implemented by any suitable wired or wireless communication link.

Computing device302may be implemented by any suitable combination of hardware and software. To illustrate, computing device302may be implemented by a mobile device (e.g., a mobile phone, a laptop, a tablet computer, etc.), a desktop computer, a clinical tool configured to facilitate fitting the cochlear implant system to the recipient, and/or any other suitable computing device as may serve a particular implementation. As an example, computing device302may be implemented by a mobile device configured to execute an application (e.g., a “mobile app”) that may be used by a user (e.g., the recipient, a clinician, and/or any other user). In some instances, such applications may be configured to control one or more settings of sound processor202and/or cochlear implant102and/or to perform one or more operations (e.g., diagnostic operations, fitting operations, etc.) with respect to data generated by sound processor202and/or cochlear implant102.

In some examples, computing device302may be configured to control an operation of cochlear implant102by transmitting one or more commands to cochlear implant102by way of sound processor202. Likewise, computing device302may be configured to receive data generated by cochlear implant102by way of sound processor202. Alternatively, computing device302may interface with (e.g., control and/or receive data from) cochlear implant102directly by way of a wireless communication link between computing device302and cochlear implant102. In some implementations in which computing device302interfaces directly with cochlear implant102, sound processor202may or may not be included in cochlear implant system100.

Computing device302is shown as having an integrated display306. Display306may be implemented by a display screen or touchscreen, for example, and may be configured to display content generated by computing device302. Additionally or alternatively, computing device302may be communicatively coupled to an external display device (not shown) configured to display the content generated by computing device302.

In some examples, computing device302represents a fitting device configured to be selectively used (e.g., by a clinician) to fit sound processor202and/or cochlear implant102to the recipient. In these examples, computing device302may be configured to execute a fitting program configured to determine and set one or more operating parameters of sound processor202and/or cochlear implant102to values that are optimized for the recipient. As such, in these examples, computing device302may not be considered to be part of cochlear implant system100. Instead, computing device302may be considered to be separate from cochlear implant system100such that computing device302may be selectively coupled to cochlear implant system100when it is desired to fit sound processor202and/or cochlear implant102to the recipient.

As one example of functionality that cochlear implant system100or a fitting system associated therewith (e.g., a fitting system separate from cochlear implant system100such as by being implemented by a computing device302in the manner described above) may perform,FIG.4shows an illustrative method400. Method400may serve as an illustrative method for fitting a hearing system to a recipient based on cortical potentials of the recipient. Method400may be performed by any configuration or implementation of cochlear implant system100described herein or by another suitable hearing system or medical system as may serve a particular implementation. For instance, method400may be performed by an implementation of cochlear implant system100such as implementation200ofFIG.2or implementation300ofFIG.3. In other examples, method400may be performed by a fitting system separate from the hearing system, or by another type of hearing system or non-hearing medical system as may serve a particular implementation (e.g., an electroacoustic hearing system, a hearing aid system, a bimodal system, etc.).

WhileFIG.4shows illustrative operations according to one embodiment, other embodiments may omit, add to, reorder, and/or modify any of the operations shown inFIG.4. In some examples, multiple operations shown inFIG.4or described in relation toFIG.4may be performed concurrently (e.g., in parallel) with one another, rather than being performed sequentially as illustrated and/or described.

In some examples, the operations ofFIG.4may be performed in real time so as to provide, receive, process, and/or use data described herein immediately as the data is generated, updated, changed, exchanged, or otherwise becomes available. Moreover, certain operations described herein may involve real-time data, real-time representations, real-time conditions, and/or other real-time circumstances. As used herein, “real time” will be understood to relate to data processing and/or other actions that are performed immediately, as well as conditions and/or circumstances that are accounted for as they exist in the moment when the processing or other actions are performed. For example, a real-time operation may refer to an operation that is performed immediately and without undue delay, even if it is not possible for there to be absolutely zero delay. Similarly, real-time data, real-time representations, real-time conditions, and so forth, will be understood to refer to data, representations, and conditions that relate to a present moment in time or a moment in time when decisions are being made and operations are being performed (e.g., even if after a short delay), such that the data, representations, conditions, and so forth are temporally relevant to the decisions being made and/or the operations being performed.

Each of operations402-406of method400will now be described in more detail as the operations may be performed by cochlear implant system100(e.g., by processing unit108), an implementation thereof, or another suitable hearing system, medical system, or dedicated fitting system.

At operation402, cochlear implant system100may direct the cochlear implant to apply stimulation to the recipient by way of the array of electrodes106of electrode lead104. This stimulation may be provided in any of the ways described above in relation toFIGS.1-3, such as by using any suitable sound processing programs, by basing the stimulation on any suitable audio source (e.g., microphone204, an audio input signal provided by computing device302, etc.), and so forth. The stimulation provided at operation402by way of electrodes106may be electrical stimulation that is applied to the cochlea in a tonotopic manner in which stimulation associated with different frequencies is applied at different parts of the recipient's cochlea that correspond to the different frequencies. In some examples, electrical stimulation provided at operation402may be provided together with acoustic stimulation provided by way of a loudspeaker (e.g., such as for one of the electroacoustic hearing system implementations of cochlear implant system100mentioned above).

As will be described in more detail below, the stimulation that the cochlear implant is directed to apply at operation402may, in certain examples, serve as stimulation configured to evoke responses (e.g., evoked cortical potentials, etc.) from the recipient. In other examples, stimulation aimed at evoking a response from the recipient may not be employed or may be separate from electrical stimulation applied as part of operation402. Regardless of whether or not electrodes106of electrode lead104are used to apply stimulation to evoke a response, however, it will be understood that one or more of these same electrodes106that are used to apply stimulation during normal operation of cochlear implant system100may also be employed for detecting certain cortical potentials that are produced by the recipient and used to perform fitting procedures described herein.

At operation404, cochlear implant system100may detect one or more cortical potentials produced by the recipient. As mentioned above, the cortical potentials detected at operation404may be detected by way of one or more electrodes included in the array of electrodes106of cochlear implant system100(i.e., one or more electrodes from the same array of electrodes106used to provide stimulation to the recipient at operation402). In certain examples, along with or instead of being detected by way of the one or more electrodes106of cochlear implant system100, one or more cortical potentials and/or other evoked or non-evoked responses (e.g., the cortical potentials of operation404) may also be detected using electrodes or other sensors other than the electrodes106. For instance, external electrodes placed on the head of the recipient, implanted electrodes dedicated to cortical potential monitoring, and/or other such electrodes may be employed in certain implementations.

In certain examples, cochlear implant system100may perform operation404automatically and/or in an automated way (e.g., without necessarily being initiated and/or overseen by a human being such as a clinician). In other examples, however, a human user (e.g., a clinician responsible for performing a fitting procedure with respect to cochlear implant system100, the recipient, a caretaker of the recipient, etc.) may be involved in directing the performance of operation404. For instance, the detecting of the cortical potential at operation404may be performed in these examples under direction of the user such as by being initiated by the user, by being performed based on input from the user, by using electrodes or other sensors put in place or initialized by the user, or the like. In certain examples, the user may perform any of these or other tasks based on instruction provided by cochlear implant system100or a fitting system associated therewith (e.g., user instructions presented by computing device302by way of display306, etc.).

The detecting of the one or more cortical potentials at operation404may be performed under any of various suitable circumstances. For example, in certain implementations, a fitting procedure may be configured to employ cortical potentials such that operation404may be an integral part of the fitting procedure whenever the procedure is performed. While behavioral and other fitting methodologies (e.g., ECochG tests, neural response imaging (“NRI”), electrically evoked compound action potentials (“ECAPs”), etc.) may sometimes be available and well suited for facilitating and optimizing fitting procedures involving hearing systems that rely only on electrical stimulation, fitting procedures for hearing systems used by recipients retaining at least some residual hearing (e.g., electroacoustic hearing systems, bimodal hearing systems, etc.) may benefit from acoustically evoked responses such as may be represented by cortical potentials detected using electroencephalogram (“EEG”) tests or the like. In certain of these examples, cortical potentials alone may be measured, while, in other examples, a combination of cortical potentials and electrically evoked potentials (e.g., ECochG) may be used to fit an electroacoustic or bimodal system to a recipient.

Rather than being included as an integral part of the fitting procedure, cortical potentials may, in certain implementations, be detected and employed only when other modes of detecting hearing characteristics and preferences of the recipient are unavailable. For instance, certain fitting procedures may use behavioral responses provided by the recipient (i.e., verbal or other voluntary input expressed by the recipient to indicate, for instance, whether test sounds are a comfortable level, are uncomfortably loud, are just short of being uncomfortably loud, are just loud enough to be perceptible, etc.). Even in situations where behavioral responses are not available (e.g., because the recipient is unable to provide such information due to age, disability, etc.), electrically evoked responses such as ECochG, NRI, ECAP, or other responses may be available and used as a primary input to facilitate the fitting procedures. However, if behavioral and/or ECochG or other types of response methodologies are unavailable or insufficient to facilitate a particular fitting procedure under a particular set of circumstances, acoustically evoked cortical potentials (or other cortical potentials such as electrically-evoked or non-evoked potentials) may be employed.

Specifically, for instance, certain implementations of cochlear implant system100may be configured to determine, prior to or as part of operation404, that a behavioral fitting methodology and an ECochG fitting methodology (such as described above) are both unavailable for determining the fitting parameter. This may be the case due to abilities of the recipient (e.g., an ability or lack of ability to hear acoustically), circumstances surrounding how or when the fitting procedure is to be carried out, the amount or nature of human oversight that may be available for a given fitting procedure, or for various other reasons. The detecting of the one or more cortical potentials at operation404(as well as the determining of the fitting parameter based on the detected cortical potentials, as will be described below in relation to operation406) may then be performed in response to the determining that the behavioral and ECochG fitting methodologies are unavailable for determining the fitting parameter. In other words, in these implementations, cortical-potential-based fitting methodologies may be used as a fallback when other methodologies fail or are unavailable for a variety of reasons.

At operation406, cochlear implant system100may determine one or more fitting parameters based on one or more cortical potentials detected at operation404. For example, the fitting parameters may be associated with cochlear implant system100by defining characteristics of the cochlear implant system, how the cochlear implant system is to operate with respect to the recipient, or the like. The fitting parameters determined at operation406may be customized to (e.g., unique to, specific to, etc.) the cochlear implant system100itself, and/or to the particular recipient who is to use the cochlear implant system and who produced the cortical potentials upon which the fitting parameters are based. To this end, the fitting parameters may include any of the types of fitting parameters described herein and may be determined based on cortical potentials or other recipient input in any manner as may serve a particular implementation. For example, various stimulation parameters that may be determined during a fitting procedure include, but are not limited to, an M-level value representative of a most comfortable sound level for the recipient, a T-level value associated with a softest sound that the recipient is capable of hearing, an loudness threshold at which sounds become uncomfortably loud to the user, various gains or other operating parameters for the cochlear implant system, and other fitting parameters that will be described or may serve a particular implementation.

FIG.5shows an illustrative configuration500in which certain components of cochlear implant system100operate to fit the cochlear implant system to a recipient based on cortical potentials of the recipient in accordance with principles described herein. As shown inFIG.5, a brain502of a recipient may produce cortical potentials504that may be detected by electrodes106(e.g., a detecting electrode and a ground electrode) of electrode lead104as the electrodes detect electrical signals in cochlear tissue506where the electrodes are disposed.

In some examples, cortical potentials504may be evoked potentials that are emitted in response to different types of stimulation. For instance,FIG.5shows electrical stimulation508that may be applied by cochlear implant102(e.g., by directing the stimulation to be applied to cochlear tissue506by electrodes106of electrode lead104) to evoke a cortical potential response. As another example,FIG.5also shows acoustic stimulation510that may be applied by a loudspeaker512(e.g., a loudspeaker included within an electroacoustic hearing system, a bimodal hearing system with a hearing aid, etc.). Whichever type of stimulation may be applied in a particular implementation (e.g., electrical stimulation508or acoustic stimulation510) the stimulation may be directed by processing unit108, which may have some degree of control over cochlear implant102and/or loudspeaker512. Additionally, back telemetry from cochlear implant102may be provided to processing unit108to transmit data that has been detected using electrodes106of electrode lead104. For example, as shown, cortical potential data514representative of cortical potentials504that have been detected by electrodes106may be transmitted by cochlear implant102to processing unit108.

Processing unit108may be configured not only to direct stimulation to be applied to the recipient (as has been described), but may also receive and process cortical potential data514that is received from cochlear implant102. For example, processing unit108may use cortical potential data514to determine one or more fitting parameters516associated with fitting cochlear implant system100to the recipient. In some examples, the processing of cortical potential data514to determine fitting parameters516may be performed in a manner that accounts for movements of the recipient that may affect cortical potentials504or the detection thereof. Such movements may be detected by a movement sensor518, which may provide data representative of the movements of the recipient to processing unit108.

Various additional details of the components illustrated in configuration500, as well as aspects of a fitting procedure that is performed using configuration100to fit cochlear implant system100to the recipient, will now be described in relation toFIGS.6-9with further reference toFIG.5.

Brain502of the recipient of cochlear implant system100may constantly produce cortical potentials and/or other voltage fluctuations and brain waves. As used herein, a cortical potential (also known as a central potential, an auditory potential, a brain wave potential, etc.) may refer to any type of voltage fluctuation emitted by the brain (e.g., the cerebral cortex, the midbrain, the brainstem, other portions of the auditory pathway, etc.) that is detectable by way of an EEG test or another such brain wave measurement tool. For instance, processing unit108may be configured to perform an EEG test using one or more electrodes106included in the array of electrodes of electrode lead104, and the detecting of one or more cortical potentials504may be performed as part of the EEG test.

Certain cortical potentials504may be produced by normal brain activity without any specific test stimulus being applied to evoke the cortical potential response.

In contrast, other cortical potentials504may be emitted as evoked responses (i.e., evoked potentials) to a particular stimulus (e.g., electrical stimulation508, acoustic stimulation510, and/or other suitable test stimuli that evoke a reaction by brain502). For instance, event-related potentials (“ERPs”), auditory steady state responses (“ASSRs”), auditory brainstem responses (“ABRs”), electrical auditory brainstem responses (“EABRs”), mid latency responses (MLR), late latency responses (LLR), and/or other evoked responses may be included among the cortical potentials504to indicate evoked or non-evoked activity of brain502.

FIG.6shows examples of illustrative cortical potentials504that may be detected using configuration500ofFIG.5. Specifically, as shown inFIG.6, a cortical potential504-1shows an example of a non-evoked cortical potential detected when brain502is relatively neutral and not responding to any particular stimulus. While certain amplitude peaks may be present in this type of example, it is shown that it may be more difficult for processing unit108to derive helpful information from this non-evoked example. In contrast, cortical potentials504-2and504-3each represent examples of cortical potentials that are evoked in response to certain stimuli applied to the recipient. For instance, the stimulus applied to evoke the example of cortical potential504-2is shown to cause brain502to produce certain peaks such as a P1, N1, and P2peak that are each identifiable by processing unit108when cortical potential504-2is received and analyzed. As another example, the stimulus applied to evoke the example of cortical potential504-3is shown to cause brain502to produce not only the P1, N1, and P2peaks, but also to include an N2and separate P3peak (also referred to as a P300peak) that is also identifiable by processing unit108when cortical potential504-3is received and analyzed.

Certain peaks detected from different cortical potentials504may be indicative of what brain502of the recipient is experiencing even if the recipient has difficulty in articulating or otherwise behaviorally expressing that experience for various reasons. For example, as will be described in more detail below, the latency of the P1peak (e.g., how much time separates the P1peak from the application of the stimulation that evokes the cortical potential) may be indicative of how responsive brain502acts under test conditions associated with a particular stimulation. As another example, the P3(or P300) peak may be evoked from brain502when brain502is processing a stimulus such as to make a decision based on the stimulus. As a result, the occurrence of the P3peak may be indicative that the recipient is reacting to a stimulus in a particular manner that goes beyond a physiological reflexive reaction. For example, the presence of the P3peak in cortical potential504-3may signify that something about the stimulation applied in that example (e.g., a change to the stimulation as compared to stimulation applied to evoke cortical potential504-2, etc.) is consciously identified by the recipient as being differentiable from other stimuli that have been applied (e.g., the stimulus is novel, etc.). Accordingly, the presence or absence of the P3peak in response to different stimulation configurations may be interpreted to identify certain aspects of how the recipient perceives the stimulation (e.g., whether the recipient can differentiate or discriminate between different stimuli, etc.).

As one example of how the presence or absence of the P3peak may be useful to objectively analyze the experience of brain502without needing to rely on behavioral feedback deliberately provided by the recipient, a first stimulus that evokes cortical potential504-2(without a P3peak) and a second stimulus that evokes cortical potential504-3(with a P3peak) will be considered. In this example, both first and second stimuli could include a same electrical stimulation component while only the second stimulus includes an acoustic stimulation component. Alternatively, each stimulus in this example could include both electrical and acoustic stimulation components, but the acoustic stimulation component may be of greater intensity in the second stimulus than the in the first stimulus.

While cortical potential504-2illustrates several expected peaks (e.g., P1, N1, P2, etc.), it may be seen that the first stimulus associated with cortical potential504-2has failed to elicit a P3peak. In contrast, due to the difference between the first stimulus and the second stimulus,FIG.6shows that a P3peak is present in cortical potential504-3after the other expected peaks (i.e., after the P1, N1, and P2peaks).

As processing unit108objectively evaluates these differences (e.g., in an effort to determine one or more fitting parameters516) processing unit108may determine, for a given set of fitting parameters516, whether the recipient is able to differentiate the different stimuli. From this determination, it may be determined whether the recipient has viable acoustic hearing (e.g., residual hearing at certain frequencies, etc.) and/or how sensitive or effective the acoustic hearing of the recipient might be. For example, processing unit108may detect the absence of the P3peak in cortical potential504-2and the presence of the P3peak in cortical potential504-3as different stimuli are presented. The stimuli may differ in any suitable way such as mentioned above. For instance, after only electrical stimulation has been applied for one or more EEG tests (resulting in cortical potentials such as cortical potential504-2), an EEG test may be performed where an acoustic stimulation component is also provided with the electrical stimulation component. If the recipient identifies that the stimulation is different (i.e., because the recipient perceives the acoustic stimulus as being separate from the electrical stimulus), the P3peak may be detectable within the resultant cortical potential (e.g., such as shown in cortical potential504-3) and processing unit108may conclude that the recipient retains at least some acoustic hearing ability.

When the cortical potential produced by the recipient indicates that the recipient perceives acoustic stimulation that has evoked the cortical potential in this way (e.g., by processing unit108identifying the presence of the P3peak on cortical potential504-3), processing unit108may be configured to provide a recommendation to a user. For instance, based on the detected cortical potential indicating that the recipient perceives the acoustic stimulation, processing unit108may make a recommendation to a user (e.g., a clinician, the recipient, etc.) that a hearing system that leverages both electrical and acoustic stimulation (i.e., applies both electrical and acoustic stimulation to the recipient) is to be prescribed for use by the recipient. As one example, a recommendation for an electroacoustic hearing system or a bimodal hearing system with a hearing aid (rather than, for example, a bilateral cochlear implant system or another such hearing system that relies exclusively on electrical stimulation) may be made such that the recipient may benefit from his or her ability to perceive acoustic stimulation.

In contrast, if the recipient fails to identify that the stimulation is different in this testing scenario (i.e., because the recipient cannot sufficiently perceive the acoustic stimulus as being separate from the electrical stimulus), the P3peak may be absent on each cortical potential (e.g., such that a waveform such as cortical potential504-3is never generated) and processing unit108may determine that the recipient does not have a useable acoustic hearing ability. In this example, processing unit108may make a recommendation to the user that an electric-stimulation-only hearing system (e.g., a bilateral cochlear implant system) is to be prescribed for use by the recipient.

Another example will now be considered to illustrate how the analysis of cortical potentials504(and including the identification of the presence and/or absence of P3peaks on different cortical potentials) may be employed in certain implementations. In this example, the stimulation provided for each test may be the same, and may include a plurality different stimuli (e.g., two simple or complex tones of different pitches, two vowels, two spectral ripple stimuli which differ in either modulation depth or modulation frequencies, etc.). In these tests, different cochlear implant system programming (e.g., using different test parameters) may be applied for different tests and the presence or absence of the P3peak may be used to indicate how well the programming for a given test allows the recipient to differentiate between the different components of the stimulus. For example, programming changes may lead to different outcomes for the cortical potentials produced by the recipient, which may indicate the extent to which the programming changes help the recipient discriminate between different stimuli.

The cortical potential produced and detected under these testing circumstances may be used to indicate the extent to which the recipient may retain usable acoustic hearing ability or used for other suitable purposes. For example, processing unit108may provide the same stimulus and different programming parameters for each test and may determine which programming parameters are optimal based on the size, latency, or other aspects of the P3peak detected in the resultant cortical potential. For example, an optimal set of test parameters (e.g., fitting parameters that are optimally fitted to a recipient) may allow the recipient to successfully discriminate between different sounds even when the difference between the sounds is relatively slight. Accordingly, test parameters that lead a recipient to produce strong P3peaks for relatively minor stimulation differences may be determined to be more optimal fitting parameters than fitting parameters that lead the recipient to produce weak P3peaks or fail to produce P3peaks at all.

Returning toFIG.5, different types of test stimulation (e.g., stimulation508and510) are shown. In certain examples, processing unit108may be configured to direct such test stimulation to be applied to the recipient to thereby evoke responses such as cortical potentials504-2and504-3illustrated inFIG.6. In such examples where cortical potentials504are evoked potentials produced by the recipient (e.g., by brain502of the recipient) in response to test stimulation, the test stimulation may be implemented by at least one of: 1) electrical stimulation applied to the recipient by way of the array of electrodes106(e.g., the electrodes106shown in configuration500or one or more other electrodes of electrode lead104), or 2) acoustic stimulation applied to the recipient by loudspeaker512as the loudspeaker is directed by processing unit108.

Electrical stimulation508may be applied by electrode lead104in any of the ways and by any of the cochlear implant system100implementations that have been described. In contrast, acoustic stimulation510may be provided only by hearing system implementations that include or are associated with a loudspeaker512that the processing unit108is able to direct.

As one example, cochlear implant system100may be included within a bimodal hearing system together with a hearing aid system employed contralaterally to cochlear implant system100on a different ear of the recipient than cochlear implant system100. In this example, acoustic test stimulation510may be provided by a loudspeaker512that is included within the hearing aid system and is configured to provide acoustic stimulation510when directed by processing unit108. For example, the cochlear implant and hearing aid systems included within the bimodal hearing system may be communicatively coupled to one another by way of a wireless link such that the processing unit108of the cochlear implant system may direct tests that rely on acoustic stimulation applied by a loudspeaker512of the hearing aid system.

As another example, cochlear implant system100may be implemented as an electroacoustic hearing system that includes a loudspeaker512as part of the electroacoustic hearing system. In this example, the loudspeaker512of the electroacoustic hearing system may apply acoustic test stimulation510to the recipient as directed by processing unit108of the electroacoustic hearing system. In still other examples, a loudspeaker512that is not included within the implementation of cochlear implant system100may be used for testing purposes and may be controlled by an implementation of processing unit108such as a clinical fitting tool, a mobile device, or another type of computing device302.

Fitting parameters516may be generated by processing unit108in any suitable way and may include any fitting parameters as may serve a particular implementation. To illustrate,FIGS.7-9show illustrative aspects of how certain fitting parameters may be determined based on detected characteristics of cortical potentials504that are detected as part of fitting tests performed on the recipient of cochlear implant system100and that are represented by cortical potential data514received from cochlear implant102.

FIG.7, for example, shows amplitudes of a particular peak (e.g., the P1peak, etc.) for cortical potentials504measured as part of several different fitting tests. More particularly,FIG.7shows a graph having a horizontal axis along which different fitting tests are represented and a vertical axis along which is represented a respective peak amplitude value for each particular peak detected as part of each fitting test. For example, a respective amplitude702(e.g., one of amplitudes702-1through702-9) may be determined as the amplitude of the P1peak of each respective cortical potential504detected as part of each different fitting test that is performed.

As shown, based on these amplitudes702, various fitting parameters516may be determined. For instance, one fitting parameter may be a T-level704that is representative of a softest sound level the recipient is capable of perceiving. T-level704may be determined based on the lowest amplitude702that is non-zero or that meets a particular threshold level. Any non-zero amplitude702(or amplitude that satisfies the particular threshold level) may indicate that brain502of the recipient perceived the stimulus, and the smallest of all such amplitudes702(i.e., amplitude702-1in the example ofFIG.7) may represent the stimulus that is the smallest that the recipient is capable of perceiving. Accordingly, as shown, T-level704may correspond to amplitude702-1(e.g., may be derived based on the stimulus that was applied to evoke the cortical potential associated with amplitude702-1).

Another fitting parameter516that processing unit108may determine based on cortical potential data514may be an M-level706that is representative of a most comfortable sound level for the recipient. M-level706may be determined based on whichever of the amplitudes702is nearest to an amplitude level708that is associated with the most comfortable sound level for the recipient. For example, it may be expected that a particular peak amplitude level is associated with comfortable and desirable sound levels as perceived by the recipient, and this particular level may be used as amplitude level708. Whichever of the fitting tests evokes a cortical potential having an amplitude702closest to this ideal level (i.e., the fitting test associated with amplitude702-6in this example) may be used to derive M-level706. Accordingly, as shown, M-level706may correspond to amplitude702-6(e.g., may be derived based on the stimulus that was applied to evoke the cortical potential associated with amplitude702-6).

Yet another fitting parameter516that processing unit108may determine based on cortical potential data514may be a loudness threshold710that is representative of an upper comfort level at which the recipient perceives sound as uncomfortably loud. Loudness threshold710may be determined based on whichever of the amplitudes702is nearest to, but less than, an amplitude level712that is associated with the sound level at which the recipient is likely to perceive pain, receive hearing damage, or otherwise subjectively find the sound to be too loud. For example, it may be expected that a particular peak amplitude level is associated with sound levels that are just loud enough to be uncomfortable, harmful, or otherwise undesirable for the recipient, and this particular level may be used as amplitude level712. Whichever of the fitting tests evokes a cortical potential having an amplitude702closest to, but less than, this upper level (i.e., the fitting test associated with amplitude702-8in this example) may be used to derive loudness threshold710. Accordingly, as shown, loudness threshold710may correspond to amplitude702-8(e.g., may be derived based on the stimulus that was applied to evoke the cortical potential associated with amplitude702-8).

In still other examples, other fitting parameters516may be determined by processing unit108based on cortical potential data514. For instance, parameters associated with optimizing the bandwidth and/or gain of acoustic stimulation being provided may be determined based on peak amplitudes detected for different fitting tests in any manner as may serve a particular implementation. As another example, parameters determined to help optimize power consumption or other characteristics of cochlear implant system100for the recipient may be determined.

Along with determining fitting parameters516based on differences in peak amplitudes702that may be detected in different fitting tests, processing unit108may also determine certain fitting parameters516based on other characteristics that may be detected in different fitting tests. For example,FIG.8shows latencies of a particular peak (e.g., the P1peak, the P3peak, etc.) for cortical potentials504as part of the same or other fitting tests as represented inFIG.7. More particularly,FIG.8shows a graph having a vertical axis along which different fitting tests are represented and a horizontal axis along which is represented a respective peak latency time for each particular peak detected as part of each fitting test. For example, a respective latency802(e.g., one of latencies802-1through802-10) may be determined as the latency of the relevant peak (e.g., the P1peak, the P3peak, etc.) of each respective cortical potential504detected as part of each different fitting test that is performed.

As shown, based on these latencies802, various fitting parameters516may be determined. For instance, the latency at which cortical responses are received for different fitting tests may be used as an indicator of which programming configuration (e.g., which fitting parameters, etc.) will be most optimal for the recipient. Specifically, the time it takes for the brain to react to a particular acoustic stimulus, which is measured as the latency at which a particular cortical potential peak is detected, may be indicative of the quality level the brain perceived for the test stimulation. In other words, for example, stimuli that evoke lower-latency cortical potentials (e.g., more immediate peaks or latencies802that are closer to the left-hand side of the graph inFIG.8) may be determined to be more optimal for the recipient than stimuli that evoke higher-latency cortical potentials (e.g., more delayed peaks or latencies802that are closer to the right-hand side of the graph inFIG.8). As such, latencies802measured for cortical potentials504evoked by different stimuli may be used to quantify relative contributions of electric and acoustic components, and, in general, to optimize the mix between the electric and acoustic stimulation components. For example, the configuration that results in the smallest latency may indicate the least effort for the brain of the recipient and may thus be considered the most optimal.

In one example, these principles may be implemented by cochlear implant system100as follows. Processing unit108may detect a plurality of cortical potentials504that are produced by the recipient during a plurality of different fitting tests each employing a different fitting test configuration. Processing unit108may then determine a respective latency802for each of the plurality of cortical potentials504produced by the recipient during the plurality of different fitting tests. For instance, as shown, latencies802-1through802-10may coincide with when a particular peak is detected to arrive within the cortical potential evoked by each fitting test. Processing unit108may determine one or more fitting parameters516by determining a “best latency” of the respective latencies802determined for each of the plurality of cortical potentials. The best latency may be the latency802produced by the recipient during a particular fitting test of the plurality of different fitting tests. As such, and based on the determining of the best latency, processing unit108may select, as the one or more fitting parameters516, one or more parameters used during the particular fitting test that resulted in the best latency. For example, whichever parameters were used in the configuration that produced the best latency may be determined to be suitable or the most optimized for future use of cochlear implant system100by the recipient and may therefore be selected for use in the future as parameters516.

The “best latency” of the measured latencies802may be defined in any suitable way and the determination of whether a particular measured latency802is the “best” may be made in any manner as may serve a particular implementation. As one example, the “best” latency may be defined as a latency that first satisfies a particular latency threshold804as the respective latencies are being determined for each of the plurality of cortical potentials504. In other words, the “best” latency may be the first latency of a tested configuration that satisfies (e.g., is less than) a particular latency threshold. As shown inFIG.8, and assuming that the fitting tests are performed in order starting from the bottom (the fitting test associated with latency802-1) and moving upward (up to the fitting test associated with latency802-10), the first three fitting tests may each fail to produce a latency802that satisfies latency threshold804(i.e., since latencies802-1through802-3each fall to the right of latency threshold804). The fourth fitting test, however, is shown to be the first one to produce a latency802(i.e., latency802-4) that does satisfy latency threshold804. Accordingly, latency802-4may be considered to be the “best latency” in this example when the best latency is defined in this way.

As another example, the “best” latency may be defined as a shortest latency802of the respective latencies802after all the respective latencies802have been determined for each of the plurality of cortical potentials504. In other words, the “best” latency in these examples may only be determined after each of a plurality of configurations has been tested and the latency results are being compared to determine the lowest one. As shown inFIG.8, regardless of what order the fitting tests are performed in, when all the tests have been performed it is the fitting test associated with latency802-5that produces the shortest latency of all. Accordingly, latency802-5may be considered to be the “best latency” in this example when the best latency is defined in this manner.

The stimulation applied to evoke cortical potentials504corresponding to the different fitting tests represented inFIGS.7and8may include tones of various frequencies and/or various broad-band noises, as well as unfiltered or filtered speech stimuli. As such, in certain examples, processing unit108may determine any of the fitting parameters516described herein as broadband parameters that are to be applied for every channel, while, in other examples, the fitting parameters516may be determined on a frequency-by-frequency or channel-by-channel basis. For example, T-level, M-level, loudness, and other thresholds described herein may be assessed for each of a variety of frequencies or frequency ranges.

To illustrate,FIG.9shows various sets of fitting parameters516that may be determined for different sound frequencies relevant to human hearing. Specifically, as shown inFIG.9, a frequency scale902is shown to extend from approximately 20 Hz (i.e., the lowest frequency general perceivable by the human hear) to approximately 20 kHz (i.e., the highest frequency generally perceivable by the human ear). A plurality of sound frequencies904(e.g. sound frequencies or frequency ranges904-1through904-9) are shown along frequency scale902, each with several respective fitting parameters516associated with that sound frequency904.

Processing unit108may perform the determining of fitting parameters516by determining respective sets906(e.g., sets906-1through906-3) of fitting parameters516. For example, a first set906-1of fitting parameters may include fitting parameters associated with a T-level, a second set906-2of fitting parameters may include fitting parameters associated with an M-level, a third set906-3of fitting parameters may include fitting parameters associated with a loudness threshold, and so forth for any of the fitting parameters described herein or as may serve a particular implementation. Within each set906, a different fitting parameter516is shown to be associated with a different sound frequency904. Accordingly, for example, rather than determining a single M-level to be employed by cochlear implant system100at all frequencies, this implementation may determine a set906of M-level fitting parameters516to be employed by cochlear implant system100to serve each of the various channels and/or sound frequencies904that the system covers.

Returning toFIG.5, movement sensor518may be employed to mitigate and/or resolve certain issues that may arise as processing unit108determines fitting parameters516in certain of the ways that have been described. For example, when EEG fitting tests are performed using implanted electrodes106of cochlear implant system100, certain artifacts may be present on cortical potentials504and/or on cortical potential data514as a result of movements made by the recipient as the cortical potentials were recorded. To deal with such artifacts, cochlear implant system100may include or be communicatively coupled with at least one motion sensor518such as an accelerometer or the like. Motion detected by motion sensor518may be used by processing unit108to help mitigate, correct, compensate for, and/or otherwise address unwanted artifacts on the EEG measurements.

For example, in one implementation, the detecting of cortical potentials504by cochlear implant system100may include detecting (e.g., using movement sensor518) a movement of the recipient as a raw cortical potential is measured, and determining (e.g., by processing unit108) that the movement of the recipient results in an artifact in the raw cortical potential. The detecting may then include altering the raw cortical potential to compensate for the artifact prior to the detected cortical potential504being used as a basis for the determining of any fitting parameters516.

As another example, in the same or other implementations, the detecting of cortical potentials504by cochlear implant system100may include tracking (e.g., using movement sensor518) movements of the recipient prior to cortical potentials504being measured, and determining that the tracked movements of the recipient satisfy a movement threshold. For example, the movement threshold may be satisfied only when the recipient's movements are at a minimum (i.e., when the recipient is relatively still). The detecting may include measuring cortical potentials504in response to the determining that the tracked movements satisfy the movement threshold. In other words, motion sensors518may indicate when the recipient is holding relatively still such that EEG tests or other fitting tests may be performed with a low risk of unwanted artifacts being present in the test results.

FIGS.10A and10Bshow illustrative fitting sessions1000(e.g., sessions1000-A and1000-B) during which a hearing system such as an implementation of cochlear implant system100may be fitted to a recipient based on cortical potentials of the recipient. Specifically, as shown,FIG.10Aillustrates a clinical fitting session1000-A in which a recipient1002of an implementation of cochlear implant system100undergoes fitting procedures administered by a clinician1004using a fitting device1006while both recipient1002and clinician1004are co-located together at a single site1008(e.g., at a hearing clinic or the like).

Clinical fitting sessions such as session1000-A where recipient1002and clinician1004are co-located may be scheduled periodically to allow clinician1004to check in on recipient1002in person and to monitor his or her progress with respect to cochlear implant system100. Cochlear implant system100, fitting device1006(which may implement computer device302in certain examples), and/or other technology may assist in tracking the progress of recipient1002in any suitable way. For example, cochlear implant system100may be configured detect cortical potentials produced by the recipient during different fitting sessions1000over a period of time (e.g., over several months, several years, etc.). Based on these detected cortical potentials, cochlear implant system100may track a progress of recipient1002over the period of time and provide (e.g., to clinician1004by way of fitting device1006) an indication of the tracked progress of the recipient over the period of time.

In some examples, the tracked progress may be based on the detection of P3peaks over time (e.g., from fitting session1000to fitting session1000, etc.) to determine if a particular recipient is progressing in a rehabilitation regime or if the progression of the recipient is insufficient (e.g., below a threshold, etc.). Upon making such a determination, cochlear implant system100may be configured to provide input regarding the progress (e.g., a warning, etc.) to recipient1002and/or to clinician1004. In some examples, cochlear implant system100may provide a visual display of P3peaks during or subsequent to clinical fitting sessions such as session1000-A to help recipient1002and clinician1004track the recipient's development and progress. For example, such a visual display may be provided to a mobile device of recipient1002, to fitting device1006of clinician1004, to another implementation of computing device302, or to another suitable display device.

Additionally or alternatively, the tracked progress may be based on a detection and analysis of binaural interaction components (“BICs”) associated with bilateral hearing systems (e.g., bilateral cochlear implant systems, bimodal hearing systems, etc.). BICs may serve as a particular type of cortical potential that indicate the extent to which both sides of the bilateral hearing system are engaging with one another. In other words, a BIC measurement may indicate the difference between how a recipient benefits from a bilateral hearing system as compared to how the recipient would benefit from only the sum of the unilateral left and right hearing systems. Accordingly, cochlear implant system100may use BIC measurements to optimize interaural time difference (“ITD”) and/or interaural level difference (“ILD”) alignment among electrodes and levels. As with the P3peak tracking described above, progress related to BIC measurements for recipient1002may be tracked and displayed using a mobile device of recipient1002, fitting device1006of clinician1004, or another suitable device.

In still other examples, the tracked progress may be based on auditory ERPs used to monitor a cortical phase synchrony (inter-trial coherence (“ITC”)) after a recipient is treated with cochlear implant system100. Recipients such as deaf children, children with auditory neuropathy, and so forth, may typically exhibit a reduced ITC. Fortunately, cochlear implant implantation may help improve ITC, and improvements in cortical phase synchrony may serve as an objective marker of benefit from treatment. If improvements are not achieved, cochlear implant system100may indicate to clinician1004that changes in the cochlear implant system program should be recommended or implemented (e.g. by increasing levels, by prescribing an electroacoustic hearing system rather than a cochlear implant system, etc.). To this end, cochlear implant system100may perform a time-frequency decomposition of a recorded EEG cortical signal and compute the phase synchronization across trials. Hypothetically, this synchrony should improve over the course of cochlear implant use (e.g., particularly in neuropathy subjects, because the cochlear implant is providing strong electrical stimulation that is driving more robust and synchronous firing along the central auditory pathway). As with the P3peak and BIC tracking described above, progress related to cortical phase synchrony measurements for recipient1002may be tracked and displayed using a mobile device of recipient1002, a fitting device1006of clinician1004, or another suitable device.

In contrast to clinical fitting session1000-A ofFIG.10A, where recipient1002and clinician1004are co-located at site1008for the fitting session,FIG.10Billustrates a virtual fitting session1000-B during which recipient1002undergoes fitting procedures that are automatically administered or remotely overseen by clinician1004while recipient1002and clinician1004are not co-located at a single site. Specifically, as shown, during virtual fitting session1008-B, recipient1002and cochlear implant system100may be located at a first site1010-1(e.g., the recipient's home, etc.), clinician1004and fitting device1006may be located at a second, different site1010-2(e.g., the hearing clinic, etc.), and cochlear implant system100may be remotely coupled to fitting device1006by way of a network1012. In certain examples (not explicitly shown), cochlear implant system100and fitting device1006may not be communicatively coupled to one another during virtual fitting session1000-B. For instance, as described above, cochlear implant system100may automatically perform fitting procedures, in certain examples, without direction from fitting device1006or clinician1004.

As shown inFIG.10B, the detecting of the cortical potentials (e.g., cortical potentials504) and the determining of the fitting parameters based on the detected cortical potentials (e.g., fitting parameters516) may be performed as part of virtual fitting session1000-B during which the recipient is located at a first location (e.g., site1010-1) that is different from a second location (e.g., site1010-2) at which clinician1004overseeing virtual fitting session1000-B is located. In some implementations, it may be determined that it is undesirable for virtual fitting session1000-B to take place under certain circumstances. For example, if recipient1002is away from home (e.g., at work, driving to another location, engaged in a social interaction, etc.), it may be undesirable for a virtual fitting session to be initiated due to distractions that the fitting session could cause for recipient1002. Accordingly, prior to initiating virtual fitting session1000-B, cochlear implant system100may be configured to determine the first location at which the recipient is located, determine that the first location is an approved location for the recipient to be located during the virtual fitting session (e.g., determine if site1010-1where recipient1002is located is the home of recipient1002or another approved location, etc.), and initiate virtual fitting session1000-B based on the determining that the first location is an approved location.

The determining of the location at which the recipient is located and whether the location is approved may be performed in any suitable way. For example, a global positioning system (“GPS”) sensor associated with cochlear implant system100or recipient1002(e.g., built in to a mobile device carried by recipient1002and communicatively coupled to cochlear implant system100) may indicate the recipient's current geolocation in certain implementations. Additionally, measurement from a microphone of cochlear implant system100(e.g., microphone204) may be used to determine whether the time is appropriate for a virtual fitting session. For example, if the microphone signal level is low and no speech information is present, it may be determined (in combination with geolocation) that it is a suitable time for the virtual fitting session.

Virtual fitting sessions such as session1000-B may provide various advantages and conveniences that are not provided by conventional clinical fitting sessions such as session1000-A. For example, virtual fitting session1000-B may remove the need for recipient1002and/or his or her caretaker (e.g., parent in the case of a child recipient, etc.) to set an appointment for the session, to drive in to the clinic at a particular time to keep the appointment, and so forth. Moreover, virtual fitting sessions such as session1000-B may be performed more frequently than clinical fitting sessions such as session1000-A to provide more optimized and updated fitting parameters, more detailed and accurate progress tracking, and so forth.

In the preceding description, various illustrative embodiments have been described with reference to the accompanying drawings. It will, however, be evident that various modifications and changes may be made thereto, and additional embodiments may be implemented, without departing from the scope of the invention as set forth in the claims that follow. For example, certain features of one embodiment described herein may be combined with or substituted for features of another embodiment described herein. The description and drawings are accordingly to be regarded in an illustrative rather than a restrictive sense.