Cochlear Implant Directional Cue Encoding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Individuals with sensorineural hearing loss face difficulties in localizing sound sources due to distorted interaural time or level differences caused by cochlear implant signal processing, especially in unilateral CI usage or bimodal fittings, which lack effective frequency overlap between electrical and acoustic stimulation.
Innovation Solution
A cochlear stimulation system that determines the main direction of sound incidence and encodes this information into the ipsilateral auditory nerve stimulation to enhance localization ability, using techniques like spectral filtering, echo effects, or phase shifting, without requiring bilateral stimulation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If cochlear implant signal processing is used to provide electrical stimulation to the auditory nerve, then hearing function is restored, but sound localization ability deteriorates due to distorted interaural time or level differences
Solution Approach 1:
The patent introduces an intermediary processing stage that analyzes the audio signal to determine the main direction of sound incidence, then uses this directional information to modulate the electrical stimulation pattern. This intermediary step allows the system to preserve hearing function while adding directional cues that compensate for the loss of natural interaural differences.
Solution Approach 2:
The patent changes the parameters of electrical stimulation by varying the timing, intensity, or pattern of pulses across different electrodes based on the determined sound direction. By dynamically adjusting these stimulation parameters according to directional information, the system restores sound localization capability while maintaining hearing function.
2Measurement precision
If bilateral stimulation is used to improve sound localization, then localization ability improves, but device complexity and cost increase
Solution Approach 1:
The patent makes the single cochlear implant system multi-functional by enabling it to perform both hearing restoration and sound localization tasks. Through algorithmic processing of audio signals and intelligent modulation of electrical stimulation, the implant provides directional information processing capabilities that would traditionally require a second implant, thereby reducing overall system complexity.
Solution Approach 2:
The system uses the audio signal already being processed for hearing restoration to also determine directional information. By extracting spatial cues from the same audio input used for stimulation generation, the system achieves sound localization functionality without requiring additional sensors or separate processing channels, making the system self-sufficient.
Data Source
Figure 1
Figure 2~3
Figure 4
AI summary
There is provided a system for stimulation of a patient's ipsilateral cochlea (200), comprising: at least two spaced apart microphones (20, 20A, 60, 60A, 160, 160A, 220, 220A) worn by the patient for providing a first input audio signal and a second audio signal from ambient sound, respectively; a sound processor (24) for generating an ipsilateral auditory nerve stimulation signal in a plurality of output channels from at least one of the input audio signals; and a stimulation assembly (19) for being implanted within the ipsilateral cochlea and having a plurality of stimulation channels for ipsilateral stimulation of the patient's hearing according to the ipsilateral auditory nerve stimulation signal, the sound processor comprising a DOA unit (66) for determining periodically a main direction of incidence of ambient sound from a sound source by analyzing the first and second audio signals, and a directional information coding unit (68) for coding information concerning the determined main direction of incidence in the ipsilateral auditory nerve stimulation signal in manner so as to render said directional information perceivable by the patient in order to enable the patient to localize the sound source by ipsilateral cochlear stimulation.