Mandarin tone identification in cochlear implant users using exaggerated pitch contours

Alice He, Mickael L. Deroche, Judy Doong, Patpong Jiradejvong, Charles J. Limb

Research output: Contribution to journalArticlepeer-review

Abstract

Objective: To determine whether exaggerating the variations in fundamental frequency (F0) contours of Mandarin-based pitch fluctuations could improve tone identification by cochlear implant (CI) users. Methods: Twelve normal-hearing (NH) listeners and 11 CI users were tested for their ability to recognize F0 contours modeled after Mandarin tones, in 4-or 5-Alternatives forcedchoice paradigms. Two types of stimuli were used: computer-generated complex tones and voice recordings. Four contours were tested with voice recordings: flat, rise, fall, and dip. A fifth contour, peak, was added for complex tones. The F0 range of each contour was varied in an adaptive manner. A maximum-likelihood technique was used to fit a psychometric function to the performance data and extract threshold at 70% accuracy. Results: As F0 range increased, performance in tone identification improved but did not reach 100% for some CI users, suggesting that confusions between contours could always be made even with extremely exaggerated contours. Compared with NH participants, CI users required substantially larger F0 ranges to identify tones, on the order of 9.3 versus 0.4 semitones. CI users achieved better performance for complex tones than for voice recordings, whereas the reverse was true for NH participants. Confusion matrices showed that the ''flat'' tone was often a default option when the tone contour's F0 range presented was too narrow for participants to respond correctly. Conclusion: These results demonstrate markedly impaired ability for CI users to identify tonal contours, but suggest that the use of exaggerated pitch contours may be helpful for tonal language perception.

Original languageEnglish (US)
Pages (from-to)324-331
Number of pages8
JournalOtology and Neurotology
Volume37
Issue number4
DOIs
StatePublished - Mar 23 2016

Keywords

  • Cochlear implants
  • Mandarin tones
  • Pitch perception.

ASJC Scopus subject areas

  • Otorhinolaryngology
  • Sensory Systems
  • Clinical Neurology

Fingerprint Dive into the research topics of 'Mandarin tone identification in cochlear implant users using exaggerated pitch contours'. Together they form a unique fingerprint.

Cite this