A new approach for speech synthesis in cochlear implant systems based on electrophysiological factors

Abstract

BACKGROUND:

Speech synthesis models have been considered as viable tools for performance evaluation of cochlear stimulation algorithms, due to the difficulties of clinical tests.

OBJECTIVE:

The present study has developed a tool that can be used before any audio signal reconstruction algorithm, which shows more conformity with the electrophysiological parameters of the patient in evaluation of the cochlear implant stimulation algorithms.

METHODS:

In this method, excitable nerve fiber characteristics such as stimulation threshold and effective refractory period have been considered in the signal pre-reconstruction process. This algorithm subsumes the user's biological parameters (e.g., the manner of distribution of the remaining intact nerve fibers) as well as the stimulation signal parameters(e.g., stimulation rate, pulse width, amplitude of stimulation, the distance between stimulation electrode and fibers) in the signal pre-reconstruction.

RESULTS:

Effect of changes in these parameters can be observed by the number of excited fibers, which is directly related to the signal intensity and pitch frequency perceived by the user. The obtained results from simulations are in accordance with previous clinical findings. Also, the ability of the proposed tool can be seen by the correspondence between the results obtained from the proposed model and the amplitude growth functions of the cochlear implant users.

CONCLUSIONS:

This paper has introduced a tool for signal reconstruction from electrical stimulation so that a more comprehensive criterion for examination of the stimulating algorithms in cochlear implant can be achieved.

Keywords

Cochlear implant speech reconstruction electrical stimulation auditory nerve fiber

References

Loizou

. Introduction to cochlear implants. IEEE Engineering in Medicine and Biology Magazine: the Quarterly Magazine of the Engineering in Medicine & Biology Society. 1999; 18(1): 32-42.

Zeng

F-G

. Trends in cochlear implants. Trends in Amplification. 2004; 8(1): 1-34.

NIH Publication. Cochlear implants. National Institute on Deafness and Other Communication Disorders. 2013; No11-4798.

McDermott

. Music perception with cochlear implants: a review. Trends in Amplification. 2004; 8(2): 49-82.

Vandali

, Sucher

, Tsang

, McKay

, Chew

, McDermott

. Pitch ranking ability of cochlear implant recipients: A comparison of sound-processing strategies. The Journal of the Acoustical Society of America. 2005; 117(5): 3126-38.

Chen

, Zhang

. Zerocrossing-based nonuniform sampling to deliver low-frequency fine structure cue for cochlear implant. Digital Signal Processing. 2011; 21: 427-32.

Lorens

, Zgoda

, Obrycka

, Skarzynski

. Fine Structure Processing improves speech perception as well as objective and subjective benefits in pediatric MED-EL COMBI 40+ users. International Journal of Pediatric Otorhinolaryngology. 2010; 74(12): 1372-8.

Liu

, Wang

, Liu

, Zhang

. An improved speech coding strategy for cochlear implants. BMEI; 2010: IEEE.

, Nie

, Atlas

, Rubinstein

. Harmonic coherent demodulation for improving sound coding in cochlear implants. ICASSP; 2010: IEEE.

10.

Chen

, Zhang

. Zerocrossing-based nonuniform sampling to deliver low-frequency fine structure cue for cochlear implant. Digital Signal Processing. 2011; 21: 427-32.

11.

Chen

, Zhang

. A novel temporal fine structure-based speech synthesis model for cochlear implant. Signal Processing. 2008; 88(11): 2693-9.

12.

Chen

, Zhou

, Xiao

, Chen

, Wang

. A New Speech Coding for Improving the Quality of Cochlear Implant. BMEI; 2008: IEEE Computer Society.

13.

Nie

, Atlas

, Rubinstein

. Single sideband encoder for music coding in cochlear implants. ICASSP; 2008: IEEE.

14.

Sit

, Simonson

, Oxenham

, Faltys

, Sarpeshkar

. A Low-Power Asynchronous Interleaved Sampling Algorithm for Cochlear Implants That Encodes Envelope and Phase Information. IEEE Transactions on Biomedical Engineering. 2007; 54(1): 138-49.

15.

Nie

, Stickney

, Zeng

. Encoding frequency modulation to improve cochlear implant performance in noise. IEEE Transactions on Bio-Medical Engineering. 2005; 52(1): 64-73.

16.

Chen

, Zhang

Y-T

. An integrate-and-fire-based auditory nerve model and its response to high-rate pulse train. 2007; [cited 70 4-6]; 1051-5.

17.

Chen

, Zhang

. Zerocrossing-based fine structure representation to convey Mandarin tonal information: a study on the noise effect. 30th IEEE EMBS; 2008 August; vancouver, Canada.

18.

Tabibi

, Sadjedi

. A new adaptive frequency and amplitude modulation encoding in multi channel cochlear implant. UKsim; 2011: IEEE.

19.

Bahmer

, Baumann

. New parallel stimulation strategies revisited: Effect of synchronous multi electrode stimulation on rate discrimination in cochlear implant users. Cochlear Implants International. 2012.

20.

Loizou

. Speech processing in vocoder-centric cochlear implants. Adv Otorhinolaryngol. 2006; 64: 109-43.

21.

Shannon

, Zeng

F-G

, Kamath

, Wygonski

, Ekelid

. Speech recognition with primarily temporal cues. Science. 1995; 270(5234): 303-4.

22.

Loizou

, Dorman

, Tu

. On the number of channels needed to understand speech. The Journal of the Acoustical Society of America. 1999; 106(4): 2097-103.

23.

McKay

, Carlyon

. Dual temporal pitch percepts from acoustic and electric amplitude-modulated pulse trains. The Journal of the Acoustical Society of America. 1999; 105(1): 347-57.

24.

, Carroll

, Zeng

. On acoustic simulations of cochlear implants. Conference on Implantable Auditory Prostheses, Lake Tahoe, CA; 2007.

25.

Loizou

. Mimicking the human ear. Signal Processing Magazine, IEEE. 1998; 15(5): 101-30.

26.

Botros

, Psarros

. Neural response telemetry reconsidered: II. The influence of neural population on the ECAP recovery function and refractoriness. Ear and Hearing. 2010; 31(3): 380-91.

27.

Cosetti

, Shapiro

, Green

, Roman

, Lalwani

, Gunn

et al. Intraoperative neural response telemetry as a predictor of performance. Otology & Neurotology. 2010; 31(7): 1095-9.

28.

Spivak

, Auerbach

, Vambutas

, Geshkovich

, Wexler

, Popecki

. Electrical compound action potentials recorded with automated neural response telemetry: threshold changes as a function of time and electrode position. Ear and Hearing. 2011; 32(1): 104-13.

29.

Miller

, Abbas

, Rubinstein

. An empirically based model of the electrically evoked compound action potential. Hearing Research. 1999; 135(1): 1-18.

30.

Dillier

WKLN

. A simple two-component model of the electrically evoked compound action potential in the human cochlea. Audiology & Neuro-Otology. 2000; 5: 333-45.

31.

Briaire

, Frijns

. Unraveling the electrically evoked compound action potential. Hearing Research. 2005; 205(1): 143-56.

32.

McKay

, Chandan

, Akhoun

, Siciliano

, Kluk

. Can ECAP measures be used for totally objective programming of cochlear implants? Journal of the Association for Research in Otolaryngology. 2013; 14(6): 879-90.

33.

Bruce

, Irlicht

, White

, O'Leary

, Dynes

, Javel

et al., A stochastic model of the electrically stimulated auditory nerve: Pulse-train response. Biomedical Engineering, IEEE Transactions on. 1999; 46(6): 630-7.

34.

Spoendlin

, Schrott

. Analysis of the human auditory nerve. Hearing Research. 1989; 43(1): 25-38.

35.

Rubinstein

, Miller

, Mino

, Abbas

. Analysis of monophasic and biphasic electrical stimulation of nerve. Biomedical Engineering, IEEE Transactions on. 2001; 48(10): 1065-70.

36.

Moore

. Coding of sounds in the auditory system and its relevance to signal processing and coding in cochlear implants. Otology & Neurotology. 2003; 24(2): 243-54.

37.

Bonnet

, Boermans

P-PB

, Avenarius

, Briaire

, Frijns

. Effects of pulse width, pulse rate and paired electrode stimulation on psychophysical measures of dynamic range and speech recognition in cochlear implants. Ear and Hearing. 2012; 33(4): 489-96.

38.

Cartee

, van den Honert

, Finley

, Miller

. Evaluation of a model of the cochlear neural membrane. I. Physiological measurement of membrane characteristics in response to intrameatal electrical stimulation. Hearing Research. 2000; 146(1): 143-52.

39.

Bruce

. Spatiotemporal coding of sound in the auditory nerve for cochlear implants: University of Melbourne. Department of Otolaryngology; 1997.

40.

Rattay

, Lutter

, Felix

. A model of the electrically excited human cochlear neuron: I. Contribution of neural substructures to the generation and propagation of spikes. Hearing Research. 2001; 153(1): 43-63.