Identification of speech response of cochlear implant patient using chaotic model

The enthusiasm of deep analysis of nonlinear dynamical system turns on the idea of chaos. Models of chaotic system have been used to analyze nonlinear dynamics in speech signal which has been traditionally modeled as a linear system for several decades. Nonlinear modeling of speech opens a new horizon in the field of cochlear implant devices in various aspects. These devices are designed to provide a measure of hearing to the deaf. It has been very successful in restoring partial hearing to profoundly deaf people. Despite all benefits one of the major issues is a great variability in the speech-recognition performance of cochlear implant patient. For a given type of implant, auditory performance which is defined as the ability to discriminate, detect, identify or recognize speech may vary from 0 to 100% The factors which affect are lack of understanding about cognitive and perceptual mechanism of individuals, numbers of nerve fibers and processing of sensory information. Neural response telemetry is a technique applied for testing of device to find clue for onepsilas actual hearing perception. In this technique evoked action potential has been measured which provides estimation about loudness levels of patient in different position of electrodes. This estimate does not tell about formants missing and frequency information. In this paper, chaotic analysis of speech has been presented for comparison of normal hearing response and implanted patient response.