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N Tye-Murray

Publications and source records attributed to N Tye-Murray.

35 records · Page 2Linked to original sources
PubMed1990

Effects of repair strategies on visual identification of sentences.

This investigation determined whether information elicited by repair strategies enhances an individual's ability to lipread a misperceived sentence. Five groups of subjects were each assigned one of five repair strategies: (a) asking the talker to repeat a sentence, (b) simplify it, (c) rephrase it, (d) say an important keyword, and (e) speak two sentences. Subjects viewed sentences spoken by six different talkers. When a subject did not recite a sentence verbatim, the talker performed the assigned repair strategy and then repeated the original sentence. A control group of subjects saw only the original sentence repeated twice. All five test groups demonstrated a significantly greater improvement for the second presentation score (referenced to the first presentation score) than the control group. The benefits provided by the repair strategies were independent of the talker, and benefits did not differ significantly among the groups.

Adult↗
PubMed1990

Comparison of the F0F2 and F0F1F2 processing strategies for the Cochlear Corporation cochlear implant.

In April 1985, an updated processing strategy became available for the Cochlear Corporation Nucleus cochlear implant. Whereas the original strategy codes only fundamental frequency, amplitude, and information in the second formant region, the newer strategy also codes frequencies in the first formant region. This investigation evaluated the speech recognition skills of five subjects who were experienced with both designs. On average, the addition of first formant information improved word identification in an audition-only condition and improved spondee recognition in noise. Scores for the NU 6 Monosyllabic Word Test and the Sentence Test Without Context improved from 8% (2-12%) to 28% words correct (10-42%), and from 31% (10-45%) to 64% words correct (39-84%), respectively. Scores for the Four-Choice Spondee Test in noise improved from 37% (25-50%) to 75% (45-90%). The percent correct scores for the Iowa 14-Item Consonant Confusion Test in an audition-only and vision-plus-audition condition did not vary with the change in processing strategy. However, an information transfer analysis performed on the responses to the consonant test in a vision-only and a vision-plus-audition condition suggested that the newer strategy enhances the transmission of the voicing, duration, and envelope features.

Adult↗
PubMed1990

Jaw and lip movements of deaf talkers producing utterances with known stress patterns.

This investigation determined whether prelingually deaf talkers could correctly produce stressed and unstressed syllables across known changes in stress patterning and phonetic composition. Three deaf and three hearing adults spoke sets of homogeneous syllable strings with stress patterns that they could tap successfully with a finger. Strain gauge transduction of lower lip and jaw movement indicated that both deaf and hearing subjects produced different displacements and durations for the stressed and unstressed syllables, regardless of the stress pattern. Jaw movement did not become more variable with changes in phonetic composition of the syllables. The results show no evidence that motoric abilities (as assessed in lip and jaw movements) limit deaf talkers in producing desired stress patterns.

Adult↗
PubMed1989

Alternating current at the eardrum for tinnitus reduction.

The effectiveness of alternating current (AC) stimulus on tinnitus was investigated in 10 patients who reported constant tinnitus in at least one ear. Patients were first screened to determine their responsiveness to electrical stimulation in relation to tinnitus reduction. The responsive patients were then stimulated for a treatment period of at least 10 min, during which time the tinnitus was measured. The AC stimuli (62 Hz to 8000 Hz) were applied to the eardrum of the patients via a specially constructed electrode. Psychophysical measurements (pitch matching, loudness matching, minimum masking level, and loudness and annoyance scaling) of the patient's tinnitus were made before and after electrical stimulation. Minimal masking level was determined and tinnitus scaling was performed during the treatment period. Electrical stimulation was effective in tinnitus reduction in 5 of the 10 patients. These 5 patients reported that the loudness and the annoyance of their tinnitus decreased during the treatment period. These observations were consistent with psychophysical measures of contralateral broadband noise masking. Poststimulation reduction in tinnitus varied in duration among individuals from 40 s to about 4 hr.

Adult↗
PubMed1989

Auditory consonant and word recognition skills of cochlear implant users.

Auditory consonant recognition and sentence recognition tests were administered to two subjects wearing the 3M/House cochlear implant, three subjects wearing the 3M/Vienna implant, seven subjects wearing the Cochlear Corporation (Nucleus) implant and 10 subjects wearing the Symbion implant. For the 14-item consonant test, the Symbion subjects scored an average of 41% consonants correct (17-58%), the Cochlear Corporation subjects scored an average of 34% (25-48%), the 3M/Vienna subjects scored 19% (15-26%), and the 3M/House subjects scored 11% (7-14%). An information transfer analysis performed on the consonant data suggested that subjects perceive the envelope feature relatively well and the place feature relatively poorly. All of the 3M/House and 3M/Vienna subjects scored 0% words correct for the sentence test. The Symbion and Cochlear Corporation subjects scored an average of 35% (0-92%) and 32% (9-45%) words correct, respectively. To better understand the variability in word recognition skills, the scores from the sentence test were correlated with the results of the information transfer analysis. The voicing and duration features did not correlate with the sentence scores very well. Place and frication features were shown to be most predictive of auditory word recognition. This finding suggests that subjects who utilize middle and high-frequency speech information are more likely to score better on open-set word recognition tests than subjects who do not.

Cochlear Implants↗
PubMed1989

The influence of final-syllable position on the vowel and word duration of deaf talkers.

Hearing talkers produce shorter vowel and word durations in multisyllabic contexts than in monosyllabic contexts. This investigation determined whether a similar effect occurs for deaf talkers, a population often characterized as lacking coarticulation in their speech. Four prelingually deafened adults and two hearing controls produced three sets of word sequences. Each set included a kernel word and six derived forms (e.g., "speed," "speedy," "speeding," etc.). The derived forms were created by adding unstressed and stressed syllables to the kernel form. A spectrographic analysis indicated that the deaf subjects did not always decrease word and vowel durations for the derivatives. Unlike hearing speakers, they often did not reduce vowel segments more than consonant segments. Three explanations are forwarded for the shortening effects. One relates to the implementation of temporal rules, the second concerns the organization imposed upon the articulators to produce speech, and the third suggests a language-independent vocal tract characteristic. The role of auditory information in developing the shortening effects is also considered.

Adult↗
PubMed1989

The recognition of vowels differing by a single formant by cochlear-implant subjects.

The ability to recognize synthetic, two-formant vowels with equal duration and similar loudness was measured in five subjects with the Cochlear and five subjects with the Symbion cochlear implants. In one set of test stimuli, vowel pairs differed only in the first-formant frequency (F1). In another set, vowel pairs differed only in the second-formant frequency (F2). When F1 differed, four of five Cochlear subjects and four of five Symbion subjects recognized the vowels significantly above chance. When F2 differed, two of five Cochlear subjects and three of five Symbion subjects scored above chance. These results suggest that implanted subjects can utilize both "place" information across different electrodes and "rate" information on a single electrode to derive information about the spectral content of the stimulus.

Adult↗
PubMed1989

Synthetic two-formant vowel perception by some of the better cochlear-implant patients.

Synthetic two-formant vowel recognition was tested in some of the better cochlear-implant users to determine their ability to resolve sounds that differ essentially in their frequency content. The vowels /i, epsilon, alpha, u/ were synthesized with equal duration and similar sound pressure level. The formant values were chosen to approximate the values of these vowels in French, German and American English. Performance ranged from 29 to 71% for the 6 patients with the Chorimac implant, from 25 to 67% for the 9 patients with the 3M/Vienna implant, from 63 to 92% for the 10 patients with the Nucleus implant from Hannover, from 17 to 79% for the 10 patients with the Duren/Cologne implant, from 54 to 100% for the 9 patients with the Symbion implant, and from 79 to 100% for the 10 Nucleus patients from the USA. Patients with each of these devices can utilize some spectral information when recognizing steady-state vowels.

Cochlear Implants↗
PubMed1988

A critique of continuous discourse tracking as a test procedure.

Continuous discourse tracking is a versatile aural rehabilitation procedure. However, it is frequently used as a test instrument to evaluate the effectiveness of communication aids and aural rehabilitation strategies or to compare communication performance using auditory and/or visual stimuli. In this report, shortcomings of this practice are reviewed. Continuous discourse tracking has numerous uncontrolled variables related to the sender (i.e., the tester), the receiver (i.e., the subject), the text materials, and repeated presentations. We suggest that tracking is inappropriate for across-subject designs. For within-subject test designs, stringent guidelines are offered to minimize some of the problems. Test developers should focus their future efforts on devising a test that reflects a natural communication interaction--one that engages the subject in a conversational style of listening.

Correction of Hearing Impairment↗
PubMed1988

Evaluation of five different cochlear implant designs: audiologic assessment and predictors of performance.

The audiologic performance of 54 postlingually deafened adults wearing cochlear implants was uniformly evaluated. The participants had 9 months' or more experience with one of five different cochlear prostheses (Los Angeles Single Channel (N = 11), Vienna Single Channel (N = 4), Melbourne Multichannel (N = 18), Utah Multichannel (N = 19), San Francisco Multichannel (N = 2). The multichannel designs enabled participants to recognize more environmental sounds, provided more speech reading enhancement, and enabled most users to understand limited speech in the sound-only condition, compared to the single-channel implant group.

Adult↗
PubMed1987

Detection of missing words in spoken text.

Two tests were conducted to examine listeners' detection of missing words in spoken paragraph contexts. Detection was assessed by presenting listeners with normal paragraphs and with paragraphs each containing a single occurrence of a missed word, an inappropriate pause, or a mispronounced word. In the first test, listeners were simply asked whether they detected any abnormalities and to describe them. The results indicated that listeners reported missed words in only 34 to 49% of the paragraphs containing such words. In the second test, a separate group of listeners was given more specific instructions beforehand, indicating the three possible types of abnormality. In this task, the correct detection of missed words rose to 96%. Taken together, the results indicate that listeners do not readily detect occasional missing words under ordinary circumstances but are capable of such detection in a task specifically focused on message abnormalities.

Attention↗
PubMed1987

Effects of vowel context on the articulatory closure postures of deaf speakers.

Using cinefluorography, this investigation evaluated how the bilabial and dorsal stop closure postures of 2 hearing and 5 deaf speakers varied with vowel context. The jaw and tongue body postures of the hearing and the 2 most intelligible deaf speakers altered with the identity of the following vowel. This did not occur consistently for the remaining deaf speakers. The results concur with a previous suggestion (Tye, Zimmerman, & Kelso, 1983) that some speakers who learn speech without audition may develop a different articulatory coordination than hearing speakers. Discovering these differences may lead to a general account for many of their intelligibility deficits.

Articulation Disorders↗
PubMed1987

Movement timing in deaf and hearing speakers: comparison of phonetically heterogeneous syllable strings.

We review evidence suggesting that deaf speakers do not move their articulators toward the following open posture throughout closure and report results from a preliminary cinefluorographic study. Two prelingually deaf and two hearing speakers produced two different strings of alternating heterogeneous monosyllables as though speaking in time with a metronome (the so-called P-center task). Events traditionally associated with vowel production appeared evenly timed throughout the productions, and, in general, the deaf speakers performed similarly to the hearing speakers. We relate the results to Fowler's (1983) interpretation of the P-center phenomenon as an indicant of continuous vowel production.

Adult↗
PubMed1986

Visual feedback during speech production.

The question of whether visual information can affect ongoing speech production arises from numerous studies demonstrating an interaction between auditory and visual information during speech perception. In a preliminary study, the effect of delayed visual feedback on speech production was examined. Two of the 13 subjects demonstrated speech errors that were directly related to the delayed visual signal. However, in the main experiment, providing immediate visual feedback of the articulators did not diminish the effects of delayed auditory feedback for 11 speakers.

Feedback↗