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J Am Acad Audiol 2000; 11(08): 418-428
DOI: 10.1055/s-0042-1748129
Original Article

Effects of Electrode Location on Speech Recognition with the Nucleus-22 Cochlear Implant

Lendra M. Friesen
House Ear Institute, Los Angeles, California
,
Robert V. Shannon
House Ear Institute, Los Angeles, California
,
William H. Slattery III
House Ear Institute, Los Angeles, California
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Abstract

Speech recognition performance was measured as a function of electrode in two experiments with the Nucleus-22 cochlear implant using 4–electrode SPEAK speech processors. In experiment 1, the four stimulated electrode pairs were shifted in 0.75–mm steps over 3 mm in the apical-basal direction. In experiment 2, the four electrodes were closely spaced and positioned apically, medially, or basally. An additional condition spaced the four electrodes as widely as possible. In experiment 1, City University of New York sentence scores showed a significant decrease in performance as the electrodes were shifted basally; no other speech measures showed a significant change with electrode location. For experiment 2, all scores were the best with the processor that had the electrodes spaced as widely as possible. In both experiments, all 4–electrode SPEAK processors produced significantly poorer speech recognition than the subject's own 20–electrode processor. These results indicate that the location of electrodes is an important factor in implant performance.

Abbreviations: C = maximum comfortable loudness levels, CI = cochlear implant, CUNY = City University of New York, NU-6 = Northwestern University Auditory Test No. 6, Τ = electrical thresholds

Key Words

Cochlear implant - electrical stimulation


Publication History

Article published online:
13 April 2022

© 2000. American Academy of Audiology. This article is published by Thieme.

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  • REFERENCES

  • Boothroyd A, Hanin L, Hnath T. (1985). CUNY Laser Videodisk of Everyday Sentences. New York: Speech and Hearing Sciences Research Center, City University of New York.
  • Boothroyd A, Nittrouer S. (1988). Mathematical treatment of context effects in phoneme and word recognition. J Acoust Soc Am 84:101–114.
  • Cochlear Corporation. (1989). Audiologist Handbook. Englewood, CO: Cochlear Corporation.
  • Cox R, Gilmore C. (1990). Development of the Profile of Hearing Aid Performance (PHAP). J Speech Hear Res 33:343–357.
  • Dorman MF, Loizou PC, Rainey D. (1997). Simulating the effect of cochlear-implant electrode insertion-depth on speech understanding. J Acoust Soc Am 102:2993–2996.
  • Fishman KE, Shannon RV, Slattery WH. (1997). Speech recognition as a function of the number of electrodes used in the SPEAK cochlear implant speech processor. J Speech Hear Res 40:1201–1215.
  • Fu Q-J, Shannon RV. (1999a). Recognition of spectrally degraded and frequency-shifted vowels in acoustic and electric hearing. J Acoust Soc Am 105:1889–1900.
  • Fu Q-J, Shannon RV. (1999b). Effects of electrode configuration and frequency allocation on vowel recognition with the Nucleus-22 cochlear implant. Ear Hear 20:332–344.
  • Fu Q-J, Shannon RV. (1999c). Effects of electrode location and spacing on speech recognition with the Nucleus-22 cochlear implant. Ear Hear 20:321–331.
  • Fu Q-J, Shannon RV, Wang X. (1998). Effects of noise and number of channels on vowel and consonant recognition: acoustic and electric hearing. J Acoust Soc Am 104:3586–3596.
  • Hillenbrand J, Getty L, Clark M, Wheeler K. (1995). Acoustic characteristics of American English vowels. J Acoust Soc Am 97:3099–3111.
  • McDermott HJ, McKay CM, Vandali AE. (1992). A new portable sound processor for the University of Melbourne/Nucleus Limited Multichannel cochlear implant. J Acoust Soc Am 91:3367–3371.
  • Robert ME. (1998). CONDOR: Documentation for Identification Test Program. Los Angeles: House Ear Institute.
  • Shannon RV, Zeng FG, Kamath V, Wygonski J, Ekelid M. (1995). Speech recognition with primarily temporal cues. Science 27:303–304.
  • Shannon RV, Zeng FG, Wygonski J. (1998). Speech recognition with altered spectral distribution of envelope cues. J Acoust Soc Am 104:2467–2476.
  • Tillman TW, Carhart R. (1966). An Expanded Test for Speech Discrimination Utilizing CNC Monosyllabic Words. Northwestern University Auditory Test No. 6, Technical Report No. SAM-TR-66–55. Brooks Air Force Base, TX: USAF School of Aerospace Medicine.
  • Tyler RS, Preece JP, Lowder MW. (1987). The Iowa Audiovisual Speech Perception Laser Videodisc. Laser Videodisc and Laboratory Report. Iowa City, IA: Department of Otolaryngology, Head and Neck Surgery, University of Iowa Hospital and Clinics.