Frequency Discrimination Ability and Stop-Consonant Identification in Normally Hearing and Hearing-Impaired Subjects

1989 ◽  
Vol 32 (1) ◽  
pp. 133-142 ◽  
Author(s):  
Marleen T. Ochs ◽  
Larry E. Humes ◽  
Ralph N. Ohde ◽  
D. Wesley Grantham
Keyword(s):  
Stop Consonant ◽  
Frequency Discrimination ◽  
Hearing Impaired ◽  
Formant Frequency ◽  
Discrimination Ability ◽  
Impaired Performance ◽  
Place Of Articulation ◽  
Listening In Noise ◽  
Burst Spectrum ◽  
Second Formant

Identification of place of articulation in the synthesized syllables/bi/,/di/, and /gi/ was examined in three groups of listeners: (a) normal hearers, (b) subjects with high-frequency sensorineural hearing loss, and (c) normally hearing subjects listening in noise. Stimuli with an appropriate second formant (F2) transition (moving-F2 stimuli) were compared with stimuli in which F2 was constant (straight-F2 stimuli) to examine the importance of the F2 transition in stop-consonant perception. For straight-F2 stimuli, burst spectrum and F2 frequency were appropriate for the syllable involved. Syllable duration also was a variable, with formant durations of 10, 19, 28, and 44 ms employed. All subjects' identification performance improved as stimulus duration increased. The groups were equivalent in terms of their identification of /di/ and /gi/ syllables, whereas the hearing-impaired and noise-masked normal listeners showed impaired performance for/bi/, particularly for the straight-F2 version. No difference in performance among groups was seen for /di/ and /gi/ stimuli for moving-F2 and straight-F2 versions. Second-formant frequency discrimination measures suggested that subjects' discrimination abilities were not acute enough to take advantage of the formant transition in the /di/and /gi/stimuli.

Effects of Aging on the Subcortical Encoding of Stop Consonants

2020 ◽  
Vol 29 (3) ◽  
pp. 391-403
Author(s):  
Dania Rishiq ◽  
Ashley Harkrider ◽  
Cary Springer ◽  
Mark Hedrick
Keyword(s):  
Older Adults ◽  
Repeated Measures ◽  
Mixed Model ◽  
Auditory Brainstem ◽  
Auditory Brainstem Responses ◽  
Aging Effects ◽  
Formant Frequency ◽  
Place Of Articulation ◽  
Second Formant ◽  
Effects Of Aging

Purpose The main purpose of this study was to evaluate aging effects on the predominantly subcortical (brainstem) encoding of the second-formant frequency transition, an essential acoustic cue for perceiving place of articulation. Method Synthetic consonant–vowel syllables varying in second-formant onset frequency (i.e., /ba/, /da/, and /ga/ stimuli) were used to elicit speech-evoked auditory brainstem responses (speech-ABRs) in 16 young adults ( M age = 21 years) and 11 older adults ( M age = 59 years). Repeated-measures mixed-model analyses of variance were performed on the latencies and amplitudes of the speech-ABR peaks. Fixed factors were phoneme (repeated measures on three levels: /b/ vs. /d/ vs. /g/) and age (two levels: young vs. older). Results Speech-ABR differences were observed between the two groups (young vs. older adults). Specifically, older listeners showed generalized amplitude reductions for onset and major peaks. Significant Phoneme × Group interactions were not observed. Conclusions Results showed aging effects in speech-ABR amplitudes that may reflect diminished subcortical encoding of consonants in older listeners. These aging effects were not phoneme dependent as observed using the statistical methods of this study.

Frequency-Discrimination Ability of Hearing-Impaired Listeners

1981 ◽  
Vol 24 (1) ◽  
pp. 108-112 ◽  
Author(s):  
P. M. Zurek ◽  
C. Formby
Keyword(s):  
Hearing Loss ◽  
Hearing Impairment ◽  
Frequency Modulation ◽  
Hearing Threshold ◽  
Low Frequency ◽  
Frequency Discrimination ◽  
Normal Hearing ◽  
Hearing Impaired ◽  
Discrimination Ability ◽  
Hearing Sensitivity

Thresholds for frequency modulation were measured by an adaptive, two-alternative, forced-choice method with ten listeners: eight who showed varying degrees of sensorineural hearing impairment, and two with normal-hearing sensitivity. Results for test frequencies spaced at octave intervals between 125 and 4000 Hz showed that, relative to normal-hearing listeners, the ability of the hearing-impaired listeners to detect a sinusoidal frequency modulation: (1) is diminished above a certain level of hearing loss; and (2) is more disrupted for low-frequency tones than for high-frequency tones, given the same degree of hearing loss at the test frequency. The first finding is consistent with that of previous studies which show a general deterioration of frequency-discrimination ability associated with moderate, or worse, hearing loss. It is proposed that the second finding may be explained: 1) by differential impairment of the temporal and place mechanisms presumed to, encode pitch at the lower and higher frequencies, respectively; and/or, 2) for certain configurations of hearing loss, by the asymmetrical pattern of cochlear excitation that may lead to the underestimation, from measurements of threshold sensitivity, of hearing impairment for low-frequency tones and consequently to relatively large changes in frequency discrimination for small shifts in hearing threshold.

Phonemic Information Transmitted by a Multichannel Electrotactile Speech Processor

1988 ◽  
Vol 31 (4) ◽  
pp. 620-629 ◽  
Author(s):  
P. J. Blamey ◽  
R. S. C. Cowan ◽  
J. I. Alcantara ◽  
G. M. Clark
Keyword(s):  
Hearing Impaired ◽  
Digital Nerve ◽  
Formant Frequency ◽  
Tactile Information ◽  
Speech Processor ◽  
Closed Sets ◽  
Open Set ◽  
Electrical Pulses ◽  
Acoustic Speech Signal ◽  
Second Formant

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.

Processing of Cues for Stop Consonant Voicing by Young Hearing-Impaired Listeners

1984 ◽  
Vol 27 (1) ◽  
pp. 112-118 ◽  
Author(s):  
Deborah Johnson ◽  
Patricia Whaley ◽  
M. F. Dorman
Keyword(s):  
Stop Consonant ◽  
Normal Hearing ◽  
Response Variability ◽  
Hearing Impaired ◽  
Hearing Impairments ◽  
Stimulus Uncertainty ◽  
Place Of Articulation ◽  
Auditory Representation ◽  
Cochlear Damage ◽  
Consonant Voicing

To assess whether young hearing-impaired listeners are as sensitive as normal-hearing children to the cues for stop consonant voicing, we presented stimuli from along VOT continua to young normal-hearing listeners and to listeners with mild, moderate, severe, and profound hearing impairments. The response measures were the location of the phonetic boundaries, the change in boundaries with changes in place of articulation, and response variability. The listeners with normal hearing sensitivity and those with mild and moderate hearing impairments did not differ in performance on any response measure. The listeners with severe impairments did not show the expected change in VOT boundary with changes in place of articulation. Moreover, stimulus uncertainty (i.e., the number of possible choices in the response set) affected their response variability. One listener with profound impairment was able to process the cues for voicing in a normal fashion under conditions of minimum stimulus uncertainty. We infer from these results that the cochlear damage which underlies mild and moderate hearing impairment does not significantly alter the auditory representation of VOT. However, the cochlear damage underlying severe impairment, possibly interacting with high signal presentation levels, does alter the auditory representation of VOT.

Stimulus Ratio Effects on Speech Discrimination by Children and Adults

1991 ◽  
Vol 34 (3) ◽  
pp. 671-678 ◽  
Author(s):  
Joan E. Sussman
Keyword(s):  
Discrimination Task ◽  
Response Pattern ◽  
Response Patterns ◽  
Speech Discrimination ◽  
Adult Group ◽  
Discrimination Accuracy ◽  
Formant Frequency ◽  
Response Strategies ◽  
Place Of Articulation ◽  
Adults And Children

This investigation examined the response strategies and discrimination accuracy of adults and children aged 5–10 as the ratio of same to different trials was varied across three conditions of a “change/no-change” discrimination task. The conditions varied as follows: (a) a ratio of one-third same to two-thirds different trials (33% same), (b) an equal ratio of same to different trials (50% same), and (c) a ratio of two-thirds same to one-third different trials (67% same). Stimuli were synthetic consonant-vowel syllables that changed along a place of articulation dimension by formant frequency transition. Results showed that all subjects changed their response strategies depending on the ratio of same-to-different trials. The most lax response pattern was observed for the 50% same condition, and the most conservative pattern was observed for the 67% same condition. Adult response patterns were most conservative across condition. Differences in discrimination accuracy as measured by P(C) were found, with the largest difference in the 5- to 6-year-old group and the smallest change in the adult group. These findings suggest that children’s response strategies, like those of adults, can be manipulated by changing the ratio of same-to-different trials. Furthermore, interpretation of sensitivity measures must be referenced to task variables such as the ratio of same-to-different trials.

scholarly journals Evaluation of working memory in relation to cochlear implant consonant speech discrimination

2021 ◽  
Vol 37 (1) ◽  
Author(s):  
Mai M. El Ghazaly ◽  
Mona I. Mourad ◽  
Nesrine H. Hamouda ◽  
Mohamed A. Talaat
Keyword(s):  
Working Memory ◽  
Speech Perception ◽  
High Frequency ◽  
Word List ◽  
Frequency Discrimination ◽  
Frequency Resolution ◽  
Speech Discrimination ◽  
Place Of Articulation ◽  
Strong Positive Relationship ◽  
Speech And Language Development

Abstract Background Speech perception in cochlear implants (CI) is affected by frequency resolution, exposure time, and working memory. Frequency discrimination is especially difficult in CI. Working memory is important for speech and language development and is expected to contribute to the vast variability in CI speech reception and expression outcome. The aim of this study is to evaluate CI patients’ consonants discrimination that varies in voicing, manner, and place of articulation imparting differences in pitch, time, and intensity, and also to evaluate working memory status and its possible effect on consonant discrimination. Results Fifty-five CI patients were included in this study. Their aided thresholds were less than 40 dBHL. Consonant speech discrimination was assessed using Arabic consonant discrimination words. Working memory was assessed using Test of Memory and Learning-2 (TOMAL-2). Subjects were divided according to the onset of hearing loss into prelingual children and postlingual adults and teenagers. Consonant classes studied were fricatives, stops, nasals, and laterals. Performance on the high frequency CVC words was 64.23% ± 17.41 for prelinguals and 61.70% ± 14.47 for postlinguals. These scores were significantly lower than scores on phonetically balanced word list (PBWL) of 79.94% ± 12.69 for prelinguals and 80.80% ± 11.36 for postlinguals. The lowest scores were for the fricatives. Working memory scores were strongly and positively correlated with speech discrimination scores. Conclusions Consonant discrimination using high frequency weighted words can provide a realistic tool for assessment of CI speech perception. Working memory skills showed a strong positive relationship with speech discrimination abilities in CI.

Second Formant Transitions of Selected Consonant-Vowel Combinations in the Speech of Deaf and Normal-Hearing Children

1976 ◽  
Vol 19 (2) ◽  
pp. 279-289 ◽  
Author(s):  
Randall B. Monsen
Keyword(s):  
Speech Intelligibility ◽  
Normal Subjects ◽  
Normal Hearing ◽  
Hearing Impaired ◽  
Acoustic Cues ◽  
Target Frequency ◽  
Second Formant ◽  
Hearing Children

Although it is well known that the speech produced by the deaf is generally of low intelligibility, the sources of this low speech intelligibility have generally been ascribed either to aberrant articulation of phonemes or inappropriate prosody. This study was designed to determine to what extent a nonsegmental aspect of speech, formant transitions, may differ in the speech of the deaf and of the normal hearing. The initial second formant transitions of the vowels /i/ and /u/ after labial and alveolar consonants (/b, d, f/) were compared in the speech of six normal-hearing and six hearing-impaired adolescents. In the speech of the hearing-impaired subjects, the second formant transitions may be reduced both in time and in frequency. At its onset, the second formant may be nearer to its eventual target frequency than in the speech of the normal subjects. Since formant transitions are important acoustic cues for the adjacent consonants, reduced F 2 transitions may be an important factor in the low intelligibility of the speech of the deaf.

Intelligibility of Modified Speech for Young Listeners With Normal and Impaired Hearing

2002 ◽  
Vol 45 (5) ◽  
pp. 1027-1038 ◽  
Author(s):  
Rosalie M. Uchanski ◽  
Ann E. Geers ◽  
Athanassios Protopapas
Keyword(s):  
Speech Processing ◽  
Normal Hearing ◽  
Hearing Impaired ◽  
Processing Conditions ◽  
Impaired Hearing ◽  
Slowing Down ◽  
Listening In Noise ◽  
Hearing Children ◽  
Impaired Children ◽  
Hearing Impaired Children

Exposure to modified speech has been shown to benefit children with languagelearning impairments with respect to their language skills (M. M. Merzenich et al., 1998; P. Tallal et al., 1996). In the study by Tallal and colleagues, the speech modification consisted of both slowing down and amplifying fast, transitional elements of speech. In this study, we examined whether the benefits of modified speech could be extended to provide intelligibility improvements for children with severe-to-profound hearing impairment who wear sensory aids. In addition, the separate effects on intelligibility of slowing down and amplifying speech were evaluated. Two groups of listeners were employed: 8 severe-to-profoundly hearingimpaired children and 5 children with normal hearing. Four speech-processing conditions were tested: (1) natural, unprocessed speech; (2) envelope-amplified speech; (3) slowed speech; and (4) both slowed and envelope-amplified speech. For each condition, three types of speech materials were used: words in sentences, isolated words, and syllable contrasts. To degrade the performance of the normal-hearing children, all testing was completed with a noise background. Results from the hearing-impaired children showed that all varieties of modified speech yielded either equivalent or poorer intelligibility than unprocessed speech. For words in sentences and isolated words, the slowing-down of speech had no effect on intelligibility scores whereas envelope amplification, both alone and combined with slowing-down, yielded significantly lower scores. Intelligibility results from normal-hearing children listening in noise were somewhat similar to those from hearing-impaired children. For isolated words, the slowing-down of speech had no effect on intelligibility whereas envelope amplification degraded intelligibility. For both subject groups, speech processing had no statistically significant effect on syllable discrimination. In summary, without extensive exposure to the speech processing conditions, children with impaired hearing and children with normal hearing listening in noise received no intelligibility advantage from either slowed speech or envelope-amplified speech.

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