Abstract: The present invention relates to the manufacture of benzoquinones, in particular to the manufacture of a potassium salt of a benzoquinone, such as 2,5-dihydroxy-1,4-benzoquinone di-potassium salt. The potassium salt of a benzoquinone is obtained by oxidation of a hydroquinone using potassium hydroxide and hydrogen peroxide, which results in an efficient process with high yields.

Abstract: A bilateral hearing implant system has a left side and a right side. Left and right side filter bank pre-processors preprocess left and right microphone signals to generate band pass signals for each side. A bilateral signal processing arrangement processes the band pass signals in a time sequence of stimulation frames. The signal processing module includes a bilateral channel selection module synchronously selects for each stimulation frame a set of stimulation channels for each side based on spectral content of the band pass signals. Left and right side signal processing submodules process for each stimulation frame a limited subset of each side band pass signals corresponding to the selected stimulation channels to generate electrical stimulation signals.

Abstract: A signal processing arrangement generates electrical stimulation signals to electrode contacts in an implanted cochlear implant array. An input sound signal is processed to generate band pass signals that each represent an associated band of audio frequencies. A characteristic envelope signal is extracted for each band pass signal based on its amplitude. Stimulation timing signals are generated for each band pass signal, including for one or more selected band pass signals using a timing function defined to: i. represent instantaneous frequency as determined by the band pass signal temporal fine structure features, and ii. exclude temporal fine structure features occurring within a time period shorter than a band-specific upper frequency limit. The electrode stimulation signals are produced for each electrode contact based on the envelope signals and the stimulation timing signals.

Abstract: A bilateral hearing implant system has a left side and a right side. Left and right side filter bank pre-processors preprocess left and right microphone signals to generate band pass signals for each side. A bilateral signal processing arrangement processes the band pass signals in a time sequence of stimulation frames. The signal processing module includes a bilateral channel selection module synchronously selects for each stimulation frame a set of stimulation channels for each side based on spectral content of the band pass signals. Left and right side signal processing submodules process for each stimulation frame a limited subset of each side band pass signals corresponding to the selected stimulation channels to generate electrical stimulation signals.

Abstract: A bilateral hearing implant system has a left side and a right side. There is an interaural time delay (ITD) processing module on each side that adjusts ITD characteristics of the stimulation signals based on defined groups of stimulation channels that include: i. an apical channel group on each side corresponding to a lowest range of audio frequencies up to a common apical channel group upper frequency limit, wherein a common number of one or more stimulation channels is assigned to each apical channel group, and wherein corresponding apical channel group stimulation channels on each side have matching bands of audio frequencies, and ii. one or more basal channel groups on each side corresponding to higher range audio frequencies above the apical channel group upper frequency limit.

Abstract: A signal processing arrangement generates electrode stimulation signals to stimulation contacts in a cochlear implant electrode array. A signal filter bank transforms an input sound signal into band pass signals, which each represent an associated frequency band of audio frequencies. An envelope processing module processes the band pass signals in a sequence of sampling time frames, wherein for each time frame, the processing includes calculating for each band pass signal at least one signal envelope dynamic property that is changing during the time frame. A channel selection module selects one or more of the band pass signals for each time frame based on the dynamic properties to produce the electrode stimulation signals to the stimulation contacts.

Abstract: A signal processing arrangement generates electrical stimulation signals to electrode contacts in an implanted cochlear implant array. An input sound signal is processed to generate band pass signals that each represent an associated band of audio frequencies. A characteristic envelope signal is extracted for each band pass signal based on its amplitude. Stimulation timing signals are generated for each band pass signal, including for one or more selected band pass signals using a timing function defined to: i. represent instantaneous frequency as determined by the band pass signal temporal fine structure features, and ii. exclude temporal fine structure features occurring within a time period shorter than a band-specific upper frequency limit. The electrode stimulation signals are produced for each electrode contact based on the envelope signals and the stimulation timing signals.

Abstract: A signal processing arrangement generates electrode stimulation signals to stimulation contacts in a cochlear implant electrode array. A signal filter bank transforms an input sound signal into band pass signals, which each represent an associated frequency band of audio frequencies. A signal processing module processes the band pass signals in a sequence of sampling time frames, wherein for each time frame, the processing includes performing a spectral feature analysis of the band pass signals, and dynamically assigning a stimulation focus pattern to one or more of the band pass signals based on the spectral feature analysis. A stimulation coding module is configured to code the processed band pass signals for each time frame to produce the electrode stimulation signals for delivery by the stimulation contacts to a region of adjacent auditory neural tissues.

Abstract: A bilateral hearing implant system has a left side and a right side. There is an interaural time delay (ITD) processing module on each side that adjusts ITD characteristics of the stimulation signals based on defined groups of stimulation channels that include: i. an apical channel group on each side corresponding to a lowest range of audio frequencies up to a common apical channel group upper frequency limit, wherein a common number of one or more stimulation channels is assigned to each apical channel group, and wherein corresponding apical channel group stimulation channels on each side have matching bands of audio frequencies, and ii. one or more basal channel groups on each side corresponding to higher range audio frequencies above the apical channel group upper frequency limit.

Abstract: A signal processing arrangement is described for signal processing in a bilateral hearing implant system having left side and right side hearing implants. An interaural coherence analysis module analyzes system input signals to produce an interaural coherence signal output characterizing reverberation-related similarity of the input signals.

Abstract: A signal processing system is described for a bilateral hearing implant system having left side and right side hearing implants. An interaural coherence analysis module receives input signals from each hearing implant including sensing microphone signals and band pass signals, and analyzes the input signals to produce an interaural coherence signal output characterizing reverberation-related similarity of the input signals. A pulse timing and coding module for each hearing implant then processes the band pass signals to develop stimulation timing signals, wherein for one or more selected band pass signals, wherein the processing includes using an envelope gating function developed from the interaural coherence signal.

Abstract: Arrangements are described for generating electrode stimulation signals for an implanted electrode array having multiple stimulation contacts. An audio input preprocessor receives an input audio signal and generates band pass signals that represent associated bands of audio frequencies. A band pass signal analyzer analyzes each band pass signal to detect when one of the band pass signal components reaches a defined transition event state. A stimulation signal generator generates a set of electrode stimulation signals for the stimulation contacts from the band pass signals such that the electrode stimulation signals to a given stimulation contact: i. use a transition event stimulation pattern whenever a transition event is detected in a band pass signal associated with the given stimulation contact, and ii. use a different non-transition stimulation pattern after the transition event stimulation pattern until a next subsequent transition event is detected.

Abstract: A signal processing arrangement generates electrical stimulation signals to stimulation contacts in an implanted cochlear implant array. An input sound signal is decomposed into dominant psychophysically relevant frequency components, with each frequency component changing over time in frequency and level. Each frequency component is coded as a patient-specific, frequency-specific function of stimulation location, rate, and level to produce a sequence of requested stimulation events having an instantaneous frequency and level. And the electrical stimulation signals are generated from the requested stimulation events for delivery by the stimulation contacts to adjacent auditory neural tissue.

Abstract: Arrangements are described for generating electrode stimulation signals for stimulation contacts in implanted electrode arrays of a bilateral hearing implant system having electrode arrays on both the left- and right-sides. Left-side and right-side audio input signals are processed to generate corresponding left-side and right-side band pass signals, which each represent an associated band of audio frequencies in the audio input signal. Frequency-specific interaural time delays (ITDs) are estimated for the band pass signals, and the estimated ITDs are used to adjust interaural level differences (ILDs) in the band pass signals. The adjusted band pass signals then are used to generate left-side and right-side electrode stimulation signals for the stimulation contacts in the corresponding left-side and right-side electrode arrays.

Abstract: A signal processing system is described for a bilateral hearing implant system having left side and right side hearing implants. An interaural coherence analysis module receives input signals from each hearing implant including sensing microphone signals and band pass signals, and analyzes the input signals to produce an interaural coherence signal output characterizing reverberation-related similarity of the input signals. A pulse timing and coding module for each hearing implant then processes the band pass signals to develop stimulation timing signals, wherein for one or more selected band pass signals, wherein the processing includes using an envelope gating function developed from the interaural coherence signal.

Abstract: A signal processing arrangement is described for signal processing in a bilateral hearing implant system having left side and right side hearing implants. An interaural coherence analysis module analyzes system input signals to produce an interaural coherence signal output characterizing reverberation-related similarity of the input signals.

Abstract: A signal processing arrangement generates electrode stimulation signals to stimulation contacts in a cochlear implant electrode array. A signal filter bank transforms an input sound signal into band pass signals, which each represent an associated frequency band of audio frequencies. A signal processing module processes the band pass signals in a sequence of sampling time frames, wherein for each time frame, the processing includes performing a spectral feature analysis of the band pass signals, and dynamically assigning a stimulation focus pattern to one or more of the band pass signals based on the spectral feature analysis. A stimulation coding module is configured to code the processed band pass signals for each time frame to produce the electrode stimulation signals for delivery by the stimulation contacts to a region of adjacent auditory neural tissues.

Abstract: A hearing signal processor processes an input sound signal and generates an electrical communications signal for an upper range of sound frequencies, and an acoustic communications signal for a lower range of sound frequencies. An implanted electrical stimulation subsystem includes an electrode array with one or more electrode contacts in an acoustically perceivable cochlear region retaining residual natural hearing. The electrical stimulation subsystem receives the electrical communications signal and delivers corresponding electrical stimulation signals to the electrode contacts for electrical stimulation of adjacent neural tissue. An external acoustic stimulation subsystem receives the acoustic communications signal and delivers corresponding amplified acoustic stimulation signals to the ear canal of the patient.

Abstract: A signal processing arrangement generates electrical stimulation signals to electrode contacts in an implanted cochlear implant array. An input sound signal is analyzed to determine characteristic frequency components. One or more stimulation events are requested based on the timing and amplitude of the frequency component. A frequency-specific stimulation sequence (FSSS) is generated for stimulation of a plurality of adjacent electrode contacts. The FSSS starts with a stimulation pulse to the highest-frequency, most-basal electrode contact of the adjacent electrode contacts, ends with a stimulation pulse to the lowest-frequency, most-apical electrode contact of the adjacent electrode contacts, and reaches a maximum stimulation amplitude at a frequency-specific location within the cochlea corresponding to a natural traveling wave maximum. The electrode stimulation signals are then generated from the FSSS for delivery by the electrode contacts to adjacent auditory neural tissue.

Abstract: A signal processing arrangement generates electrical stimulation signals to stimulation contacts in an implanted cochlear implant array. An input sound signal is decomposed into dominant psychophysically relevant frequency components, with each frequency component changing over time in frequency and level. Each frequency component is coded as a patient-specific, frequency-specific function of stimulation location, rate, and level to produce a sequence of requested stimulation events having an instantaneous frequency and level. And the electrical stimulation signals are generated from the requested stimulation events for delivery by the stimulation contacts to adjacent auditory neural tissue.