Graeme Clark Collection

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    Phonemic information transmitted by a multichannel electrotactile speech processor
    Blamey, P. J. ; Cowan, R. S. C. ; Alcantara, J. I. ; Clark, Graeme M. ( 1988)
    A wearable electrotactile speech processor was evaluated in a study with seven normally hearing and four hearing-impaired subjects. The processor estimated the fundamental frequency, the second-formant frequency, and amplitude of the acoustic speech signal. These parameters were presented as a pattern of electrical pulses applied to eight electrodes positioned over the digital nerve bundles on one hand. The device was shown to provide useful information for the recognition of phonemes in closed sets of words using tactile information alone. The device also supplemented lipreading to improve the recognition of open-set words. The recognition of duration and first-and second-formant frequencies of vowels and the recognition of voicing and manner of consonants were improved over recognition with lipreading alone. Recognition of final consonants was improved more than recognition of initial consonants. These results indicate that the device may be useful to both severely and profoundly hearing-impaired people.
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    Interim results of open-set speech discrimination with a wearable multichannel electrotactile speech processor
    Cowan, R. S. C. ; Alcantara, J. I. ; Blamey, P. J. ; Clark, Graeme M. ( 1987)
    Abstract not available due to copyright.
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    Acoustic parameters measured by a formant-estimating speech processor for a multiple-channel cochlear implant
    Blamey, P. J. ; Dowell, R. C. ; Clark, Graeme M. ; Seligman, P. M. ( 1987)
    Abstract not available due to copyright.
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    Vowel and consonant recognition of cochlear implant patients using formant-estimating speech processors
    Blamey, P. J. ; Dowell, R. C. ; Brown, A. M. ; Clark, Graeme M. ; Seligman, P. M. ( 1987)
    Abstract not available due to copyright.
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    A formant-estimating speech processor for cochlear implant patients
    Blamey, P. J. ; Dowell, R. C. ; Brown, A. M. ; Clark, Graeme M. ; Seligman, P. M. ( 1987)
    A simple formant-estimating speech processor has been developed to make use of the “hearing” produced by electrical stimulation of the auditory nerve with a multiple-channel cochlear implant. Thirteen implant patients were trained and evaluated with a processor that presented the second formant frequency, fundamental frequency, and amplitude envelope of the speech (F0F2). Nine patients were trained and evaluated with a processor that presented the first and second formant frequencies, fundamental frequency, and first and second formant amplitudes (F0F1F2). The most common use of the speech processor was in conjunction with lipreading, so the patients were trained in lipreading plus hearing, as well as hearing alone. The F0F1F2 group performed significantly better in discrimination tasks and word and sentence recognition through hearing alone. The F0F1F2 group also showed a significantly greater improvement when hearing and lipreading was compared with lipreading alone in a speech tracking task. A study of spondee recognition in noise with hearing alone indicated that the added first formant information produced an improvement that was equivalent to a 5 dB increase in the signal-to-noise ratio.
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    Psychophysical studies relevant to the design of a digital electrotactile speech processor
    Blamey, P. J. ; Clark, Graeme M. ( 1987)
    Abstract not available due to copyright.