Abstract: An exemplary cochlear stimulation method includes applying a main current to a first electrode associated with a first pitch and disposed within a cochlea of a patient, concurrently applying a compensation current to a second electrode disposed within the cochlea and associated with a second pitch during the application of the main current, the compensation current being out-of-phase with the main current, and optimizing an amount of the compensation current to result in a target pitch being presented to the patient that is distanced from the first pitch in a pitch direction opposite a pitch direction of the second pitch in relation to the first pitch. Corresponding methods and systems are also disclosed.

Abstract: Psychophysical tests are administered to cochlear implant (CI) users to determine a spectral modulation transfer function (SMTF), the smallest detectable spectral contrast as a function of spectral modulation frequency, for each individual CI user. The determined SMTF for individual CI user is compared against a SMTF of a normal hearing person to determine the specific enhancements needed. A spectral contrast enhancement that best fits the needed enhancements for the individual CI user is selected, and a sound processing strategy is adjusted to provide customized spectral contrast enhancement for the individual CI user. The sound processing strategy implemented includes an outer hair cell model.

Abstract: Errors in pitch allocation within a cochlear implant are corrected in order to provide a significant and profound improvement in the quality of sound perceived by the cochlear implant user. The disclosure provides a tool for determining the implant fitting curve for cochlear implant system to correct pitch warping. The method presents familiar musical tunes to determine the implant fitting slope (relative alignment). In addition, in one embodiment, speech sounds may be used to determine the offset of the fitting line (absolute alignment). The use of music and speech to determine the implant fitting curve (line) and the slope is facilitated by using techniques to implement virtual electrodes to more precisely direct stimuli to the location or “place” on the cochlea.

Abstract: Errors in pitch allocation within a cochlear implant are corrected in order to provide a significant and profound improvement in the quality of sound perceived by the cochlear implant user. The disclosure provides a tool for determining the implant fitting curve for cochlear implant system to correct pitch warping. The method presents familiar musical tunes to determine the implant fitting slope (relative alignment). In addition, in one embodiment, speech sounds may be used to determine the offset of the fitting line (absolute alignment). The use of music and speech to determine the implant fitting curve (line) and the slope is facilitated by using techniques to implement virtual electrodes to more precisely direct stimuli to the location or “place” on the cochlea.

Abstract: Methods and systems of spectral tilt optimization for a cochlear implant patient include applying electrical stimulation representative of an audio signal to a patient in accordance with a spectral tilt value and optimizing the spectral tilt value in response to a measured ability of the patient to recognize at least one attribute of the audio signal.

Abstract: An exemplary method of conveying fine structure information to a cochlear implant patient includes dividing an audio signal into a plurality of analysis channels, generating electrical stimulation in accordance with the information contained within each of the analysis channels, applying the electrical stimulation to at least one stimulation site within a patient via a plurality of stimulation channels, and at least partially isolating one of the stimulation channels from a rest of the stimulation channels, wherein fine structure information is conveyed to the patient via the isolated stimulation channel. Corresponding methods and systems are also disclosed.

Abstract: A multichannel cochlear implant system spatially spreads the excitation pattern in the target neural tissue by either: (1) rapid sequential stimulation of a small group of electrodes, or (2) simultaneously stimulating a small group of electrodes. Such multi-electrode stimulation stimulates a greater number of neurons in a synchronous manner, thereby increasing the amplitude of the extra-cellular voltage fluctuation and facilitating its recording. The electrical stimuli are applied simultaneously (or sequentially at a rapid rate) on selected small groups of electrodes while monitoring the evoked compound action potential (ECAP) on a nearby electrode. The presence of an observable ECAP not only validates operation of the implant device at a time when the patient may be unconscious or otherwise unable to provide subjective feedback, but also provides a way for the magnitude of the observed ECAP to be recorded as a function of the amplitude of the applied stimulus.

Abstract: Methods and systems of optimizing sound sensation of a cochlear implant patient include dividing an audio signal into a plurality of analysis channels, generating one or more tonality indices each representing a tonality of one of the analysis channels, generating one or more stimulation pulses configured to represent the audio signal in accordance with one or more stimulation parameters, and adjusting at least one of the stimulation parameters based on at least one of the tonality indices.

Abstract: An adaptive place-pitch ranking procedure for use with a cochlear implant or other neural stimulation system provides a systematic method for quantifying the magnitude and direction of errors along the place-pitch continuum. The method may be conducted and completed in a relatively short period of time. In use, the implant user or listener is asked to rank the percepts obtained after a sequential presentation of monopolar stimulation pulses are applied to a selected spatially-defined electrode pair. The spatially-defined electrode pair may be a physical electrode pair or a virtual electrode pair. A virtual electrode pair includes at least one virtual electrode contact. Should the patient's judgment of pitch order be correct for all applied interrogations, then no further testing involving the tested electrode pair (two electrode contacts) is undertaken.

Abstract: The stimulation provided in the electrically stimulated cochlea is modulated in accordance with the amplitude of a received acoustic signal and the onset of a sound in a received acoustic signal to provide increased sound perception. An onset time that corresponds to the onset of a sound is detected in an acoustic signal associated with a frequency band. A forcing voltage and a transmitting factor are determined, wherein the forcing voltage and the transmitting factor are associated with the frequency band at the detected onset time. The acoustic signal is modulated as a function of the forcing voltage and the transmitting factor to generate an output signal. The generated output signal can be used to stimulate the cochlea. The modulation strategy can be used in conjunction with sound processing strategies that employ frequency modulation, amplitude modulation, or a combination of frequency and amplitude modulation.

Abstract: The stimulation provided in the electrically stimulated cochlea is modulated in accordance with the amplitude of a received acoustic signal and the onset of a sound in a received acoustic signal to provide increased sound perception. An onset time that corresponds to the onset of a sound is detected in an acoustic signal associated with a frequency band. A forcing voltage and a transmitting factor are determined, wherein the forcing voltage and the transmitting factor are associated with the frequency band at the detected onset time. The acoustic signal is modulated as a function of the forcing voltage and the transmitting factor to generate an output signal. The generated output signal can be used to stimulate the cochlea. The modulation strategy can be used in conjunction with sound processing strategies that employ frequency modulation, amplitude modulation, or a combination of frequency and amplitude modulation.

Abstract: Sound processing strategies for use with cochlear implant systems utilizing simultaneous stimulation of electrodes are provided. The strategies include computing a frequency spectrum of a signal representative of sound, arranging the spectrum into channels and assigning a subset of electrodes to each channel. Each subset is stimulated so as to stimulate a virtual electrode positioned at a location on the cochlea that corresponds to the frequency at which a spectral peak is located within an assigned channel. The strategies also derive a carrier for a channel having a frequency that may relate to the stimulation frequency so that temporal information is presented. In order to fit these strategies, a group of electrodes is selected and the portion of the current that would otherwise be applied to electrode(s) having a partner electrode in the group is applied to the partner electrode.

Abstract: Sound processing strategies for use with cochlear implant systems utilizing simultaneous stimulation of electrodes are provided. The strategies include computing a frequency spectrum of a signal representative of sound, arranging the spectrum into channels and assigning a subset of electrodes to each channel. Each subset is stimulated so as to stimulate a virtual electrode positioned at a location on the cochlea that corresponds to the frequency at which a spectral peak is located within an assigned channel. The strategies also derive a carrier for a channel having a frequency that may relate to the stimulation frequency so that temporal information is presented. In order to fit these strategies, a group of electrodes is selected and the portion of the current that would otherwise be applied to electrode(s) having a partner electrode in the group is applied to the partner electrode.

Abstract: Among other things, enhancing spectral contrast for a cochlear implant listener includes detecting a time domain signal. A first transformation is applied to the detected time domain signal to convert the time domain signal to a frequency domain signal. A second transformation is applied to the frequency domain signal to express the frequency domain signal as a sum of two or more components. A sensitivity of the cochlear implant listener to detect modulation of each component is obtained.

Abstract: Exemplary cochlear implant systems include an implantable cochlear stimulator configured to be implanted within a patient and generate a stimulation current having an adjustable current level, one or more electrodes communicatively coupled to the stimulator and configured to apply the stimulation current to one or more locations within an ear of the patient, and a probe configured to acquire sound data used to derive an acoustic reflectance of the ear. The implantable cochlear stimulator is configured to adjust the current level of the stimulation current until a change in the acoustic reflectance above a threshold is detected.

Abstract: Methods of denoising a neural recording signal include correlating a neural recording signal with a number of basis functions to obtain a number of weights and then multiplying the weights with the basis functions to obtain a denoised neural recording signal. The basis functions are derived using principal component analysis. Systems for denoising a neural recording signal include one or more devices configured to correlate a neural recording signal with the basis functions to obtain the weights and then multiply the weights with the basis functions to obtain the denoised neural recording signal.

Abstract: Sound processing strategies for use with cochlear implant systems utilizing simultaneous stimulation of electrodes are provided. The strategies include computing a frequency spectrum of a signal representative of sound, arranging the spectrum into channels and assigning a subset of electrodes to each channel. Each subset is stimulated so as to stimulate a virtual electrode positioned at a location on the cochlea that corresponds to the frequency at which a spectral peak is located within an assigned channel. The strategies also derive a carrier for a channel having a frequency that may relate to the stimulation frequency so that temporal information is presented. In order to fit these strategies, a group of electrodes is selected and the portion of the current that would otherwise be applied to electrode(s) having a partner electrode in the group is applied to the partner electrode.

Abstract: A multichannel neurostimulation device spatially spreads the excitation pattern in the target neural tissue by either: (1) rapid sequential stimulation of a small group of electrodes, or (2) simultaneously stimulating a small group of electrodes. Such multi-electrode stimulation stimulates a greater number of neurons in a synchronous manner, thereby increasing the amplitude of the extra-cellular voltage fluctuation and facilitating its recording. The electrical stimuli are applied simultaneously (or sequentially at a rapid rate) on selected small groups of electrodes while monitoring the evoked compound action potential (ECAP) on a nearby electrode. The presence of an observable ECAP not only validates operation of the implant device at a time when the patient may be unconscious or otherwise unable to provide subjective feedback, but also provides a way for the magnitude of the observed ECAP to be recorded as a function of the amplitude of the applied stimulus.

Abstract: Methods of automatically determining a neural response threshold current level include identifying one or more neural response signals at one or more corresponding stimulation current levels, identifying one or more non-response signals at one or more corresponding stimulation current levels, and analyzing a trend between the neural response signals and the non-response signals. Systems for automatically determining a neural response threshold current level include one or more devices configured to identify one or more neural response signals at one or more corresponding stimulation current levels, identify one or more non-response signals at one or more corresponding stimulation current levels; and analyze a trend between the neural response signals and the non-response signals.

Abstract: The present invention provides a cochlear stimulation system and method for capturing and translating fine time structure (“FTS”) in incoming sounds and delivering this information spatially to the cochlea. The system comprises a FTS estimator/analyzer and a current navigator. An embodiment of the method comprises analyzing the incoming sounds within a time frequency band, extracting the slowly varying frequency components and estimating the FTS to obtain a more precise dominant FTS component within a frequency band. After adding the fine structure to the carrier to identify a precise dominant FTS component in each analysis frequency band (or stimulation channel), a stimulation current may be “steered” or directed, using the concept of virtual electrodes, to the precise spatial location (place) on the cochlea that corresponds to the dominant FTS component. This process is simultaneously repeated for each stimulation channel and each FTS component.