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OBJECTIVE 1) To determine whether the N1-P2 acoustic change complex is elicited by a change of periodicity in the middle of an ongoing stimulus, in the absence of changes of spectral envelope or rms intensity. 2) To compare the N1-P2 acoustic change complex with the mismatch negativity elicited by the same stimuli in terms of amplitude and signal to noise(More)
The acoustic change complex (ACC) is a scalp-recorded negative-positive voltage swing elicited by a change during an otherwise steady-state sound. The ACC was obtained from eight adults in response to changes of amplitude and/or spectral envelope at the temporal center of a three-formant synthetic vowel lasting 800 ms. In the absence of spectral change, the(More)
Changed hearing occurs when sensorineural loss is acquired or increases, when hearing aids or cochlear implants are first acquired, when hearing aids are reprogrammed, and when cochlear implants are remapped. The changes affect speech perception-a process in which decisions about a talker's language output are made on the basis of sensory and contextual(More)
Interlist equivalency and short-term practice effects were evaluated for the recorded stimuli of the Computer-Assisted Speech Perception Assessment (CASPA) Test. Twenty lists, each consisting of 10 consonant-vowel-consonant words, were administered to 20 adults with normal hearing. The lists were presented at 50 dB SPL (Leq) in the presence of spectrally(More)
Recognition of words in conversational sentences of known topic was measured in nine normally hearing subjects by speechreading alone and by speechreading supplemented with auditory presentation of the output of an electroglottograph. Mean word recognition probability rose from 30% to 77% with the addition of the acoustic signal. When this signal was(More)
OBJECTIVE To investigate whether the evoked potential to a complex naturally produced speech syllable could be decomposed to reflect the contributions of the acoustic events contained in the constituent phonemes. DESIGN Auditory cortical evoked potentials N1 and P2 were obtained in eight adults with normal hearing. Three naturally produced speech stimuli(More)
The recognition of phonemes in consonant-vowel-consonant words, presented in speech-shaped random noise, was measured as a function of signal to noise ratio (S/N) in 10 normally hearing adults and 10 successful adult users of the Nucleus cochlear implant. Optimal scores (measured at a S/N of +25 dB) were 98% for the average normal subject and 42% for the(More)
Adult listeners are able to recognize speech even under conditions of severe spectral degradation. To assess the developmental time course of this robust pattern recognition, speech recognition was measured in two groups of children (5-7 and 10-12 years of age) as a function of the degree of spectral resolution. Results were compared to recognition(More)
The purpose was to determine a target for the upper frequency limit of a hearing aid that will provide access to the important spectral cues for all the sounds of English. The sibilant /s/ was studied because of its high-frequency content. Repeated tokens of /s/ were recorded from five men and five women before and between the vowels /u/, /a/, and /i/.(More)
Nasality is widely recognized as a problem in the speech of many deaf people. This paper describes one approach to the assessment of nasalization and to the development of visual aids to assist in training of velopharyngeal control. The approach involves detection of the velopharyngeal opening during voiced sounds by means of a small accelerometer attached(More)