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Purpose: Previous studies of speech articulation have shown that individuals who can perceive smaller differences between similar-sounding phonemes showed larger contrasts in their productions of those phonemes. Here, a similar relationship was examined between the perception and production of breathy voice quality. Method: Twenty females with healthy voices were recruited to participate in both a voice production and a perception experiment. Each participant produced repetitions of a sustained vowel, and acoustic correlates of breathiness were calculated. Identification and discrimination tasks were performed with a series of synthetic stimuli along a breathiness continuum. Categorical boundary location and boundary width were obtained from the identification task as a measurement of perception of breathiness. Spearman's correlation analysis was performed to estimate associations between values of boundary location and width and the acoustic correlates of breathiness from the participants' voices. Results: Significant correlations between boundary width (r = -0.53 to -0.6) and some acoustic correlates were found, but no significant relationships were observed between boundary location and the acoustic correlates. Conclusions: Speakers with small boundary widths, which suggest higher perceptual precision in differentiating breathiness, had typical voices that were less breathy, as estimated with acoustic measures, compared to speakers with large boundary widths. Our findings may support a link between perception and production of breathy voice quality.

Purpose: To assess the effects of short- and long-term changes in auditory feedback on vowel and sibilant contrasts and to evaluate hypotheses arising from a model of speech motor planning. Method: The perception and production of vowel and sibilant contrasts were measured in 8 postlingually deafened adults prior to activation of their cochlear implant speech processors, 1 month postactivation, and 1 year postactivation. Measures were taken postactivation both with and without auditory feedback. Contrast measures were also made for a group of speakers with reportedly normal hearing speaking with masked and unmasked auditory feedback. Results: Vowel and sibilant contrasts, measured in the absence of auditory feedback after 1 month of prosthesis use, were diminished compared with their values measured before prosthesis. Contrasts measured in the absence of auditory feedback after 1 year's experience with the prosthesis were increased compared with their values after 1 month's experience. In both time samples, contrasts were enhanced when auditory feedback was restored. Conclusion: The provision of prosthetic hearing to postlingually deafened adults impaired their phonemic contrasts at first, as their auditory feedback had novel characteristics. Once auditory feedback became recalibrated with prosthesis use, it could, in turn, revise feedforward commands that control the contrasts in its absence.

Analysis of data from eight adult cochlear implant users found that improvements in their production and perception of a given vowel contrast and normally hearing listeners' identification of that contrast tended to occur together. Results support the view that restoring self-hearing allows a speaker to adjust articulatory routines to ensure sufficient perceptual contrast for listeners. (Contains references.) (Author/DB)

This study analyzed 36 digitized spondaic words for speech reception threshold in an attempt to create a more homogeneous set of spondaic words for research on determining hearing loss for speech. None of the acoustic properties were correlated with word thresholds. When the threshold of each word was adjusted to the mean threshold, dispersion was greatly reduced. (DB)

The articulator positions of a man with deafness who had a cochlear implant were measured with an electromagnetic midsagittal articulometer system with and without auditory feedback via his implant. Findings suggest that the cochlear implant was providing important auditory cues that can be used to monitor speech and maintain phonemic contrasts. (Author/CR)

Purpose: To describe cochlear implant users' phoneme labeling, discrimination, and prototypes for a vowel and a sibilant contrast, and to assess the effects of 1 year's experience with prosthetic hearing. Method: Based on naturally produced clear examples of "boot," "beet," "said," and "shed" by 1 male and 1 female speaker, continua with 13 stimuli were synthesized for each contrast. Seven hearing controls labeled those stimuli and assigned them goodness ratings, as did 7 implant users at 1-month postimplant. One year later, these measures were repeated, and within category discrimination, d', was assessed. Results: Compared with controls, implant users' vowel and sibilant labeling slopes were substantially shallower but improved over 1 year of prosthesis use. Their sensitivity to phonetic differences within phoneme categories was about half that of controls. The slopes of their goodness rating functions were shallower and did not improve. Their prototypes for the sibilant contrast (but not the vowels) were closer to one another and did not improve by moving apart. Conclusions: Implant users' phoneme labeling and within-category perceptual structure were anomalous at 1-month postimplant. After 1 year of prosthesis use, phoneme labeling categories had sharpened but within category discrimination was well below that of hearing controls. KEY WORDS: speech perception, cochlear implants, hearing loss, Phoneme labeling, discrimination and, more rarely, goodness ratings have been reported for several special populations, among them children with apraxic disorders (Maassen, Groenen, & Crul, 2003), children with otitis media [...]

Two speech perception experiments were conducted with 12 normally hearing adults using a modified speech tracking procedure to determine the effects of controlling connected discourse materials and the effects of specific prompting techniques on tracking rate and subjects' responses. Results showed higher tracking rates for controlled materials. (Author/JDD)

Purpose: Previous studies of speech articulation have shown that individuals who can perceive smaller differences between similar-sounding phonemes showed larger contrasts in their productions of those phonemes. Here, a similar relationship was examined between the perception and production of breathy voice quality. Method: Twenty females with healthy voices were recruited to participate in both a voice production and a perception experiment. Each participant produced repetitions of a sustained vowel, and acoustic correlates of breathiness were calculated. Identification and discrimination tasks were performed with a series of synthetic stimuli along a breathiness continuum. Categorical boundary location and boundary width were obtained from the identification task as a measurement of perception of breathiness. Spearman’s correlation analysis was performed to estimate associations between values of boundary location and width and the acoustic correlates of breathiness from the participants’ voices. Results: Significant correlations between boundary width (r = −.53 to −.6) and some acoustic correlates were found, but no significant relationships were observed between boundary location and the acoustic correlates. Conclusions: Speakers with small boundary widths, which suggest higher perceptual precision in differentiating breathiness, had typical voices that were less breathy, as estimated with acoustic measures, compared to speakers with large boundary widths. Our findings may support a link between perception and production of breathy voice quality. [ABSTRACT FROM AUTHOR]

The American English phoneme /[are]/ has long been associated with large amounts of articulatory variability during production. This paper investigates the hypothesis that the articulatory variations used by a speaker to produce /[are]/ in different contexts exhibit systematic tradeoffs, or articulatory trading relations, that act to maintain a relatively stable acoustic signal despite the large variations in vocal tract shape. Acoustic and articulatory recordings were collected from seven speakers producing /[are]/ in five phonetic contexts. For every speaker, the different articulator configurations used to produce /[are]/ in the different phonetic contexts showed systematic tradeoffs, as evidenced by significant correlations between the positions of transducers mounted on the tongue. Analysis of acoustic and articulatory variabilities revealed that these tradeoffs act to reduce acoustic variability, thus allowing relatively large contextual variations in vocal tract shape for /[are]/ without seriously degrading the primary acoustic cue. Furthermore, some subjects appeared to use completely different articulatory gestures to produce /[are]/ in different phonetic contexts. When viewed in light of current models of speech movement control, these results appear to favor models that utilize an acoustic or auditory target for each phoneme over models that utilize a vocal tract shape target for each phoneme. © 1999 Acoustical Society of America. [ABSTRACT FROM AUTHOR]