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Biomedical subjects

R L Whitehead

Publications and source records attributed to R L Whitehead.

At least 19 recordsLinked to original sources
PubMed1998

Effect of fingerspelling task on temporal characteristics and perceived naturalness of speech in simultaneous communication.

This study investigated the effect of fingerspelling task length on temporal characteristics and perceived naturalness of speech produced during simultaneous communication. Stimulus words at four levels of fingerspelling task length were embedded in a sentence that was spoken and produced with simultaneous communication. Five temporal measures were calculated from acoustic recordings, and perceived speech naturalness was rated by a panel of listeners using a 9-point scale. Results indicated significant differences in temporal measures and naturalness ratings between the speech and simultaneous communication conditions and among levels of fingerspelling task length. Speech produced during simultaneous communication was rated as less natural and demonstrated increased interword interval, diphthong, word, and sentence durations. Regression analysis indicated significant correlations between temporal measures and perceived speech naturalness, and analysis of variance showed significant increases in segmental and interword interval durations and perceived speech unnaturalness as fingerspelling task length increased. These results are discussed in relation to previous findings regarding production and perception characteristics of speech that is altered in temporal parameters by a variety of conditions.

Communication↗
PubMed1996

Voice onset time in speech produced during simultaneous communication.

This study investigated speaking rate and voice onset time (VOT) in speech produced during simultaneous communication (SC) by speakers with normal hearing. Stimulus words initiated with voiced and voiceless plosives were embedded in a sentence that was spoken and produced with SC. VOT measures were calculated from acoustic recordings and results indicated significant differences between speech-only and SC conditions, with speech produced during SC demonstrating both slower speaking rate and increased VOT of voiceless consonants. VOTs produced during both SC and speech-only conditions followed English voicing rules and varied appropriately with place of articulation. The somewhat enlarged voicing contrast during SC was consistent with previous findings regarding the influence of rate changes on the temporal fine structure of speech (Miller, 1987) and was similar to the voicing contrast results reported for clear speech by Picheny, Durlach, and Braida (1986).

Communication↗
PubMed1995

Temporal characteristics of speech in simultaneous communication.

The purpose of this investigation was twofold: (a) to determine if there are changes in specific temporal characteristics of speech that occur during simultaneous communication, and (b) to determine if known temporal rules of spoken English are disrupted during simultaneous communication. Ten speakers uttered sentences consisting of a carrier phrase and experimental CVC words under conditions of: (a) speech, (b) speech combined with signed English, and (c) speech combined with signed English for every word except the CVC word that was fingerspelled. The temporal features investigated included: (a) sentence duration, (b) experimental CVC word duration, (c) vowel duration in experimental CVC words, (d) pause duration before and after experimental CVC words, and (e) consonantal effects on vowel duration. Results indicated that for all durational measures, the speech/sign/fingerspelling condition was longest, followed by the speech/sign condition, with the speech condition being shortest: It was also found that for all three speaking conditions, vowels were longer in duration when preceding voiced consonants than vowels preceding their voiceless cognates, and that a low vowel was longer in duration than a high vowel. These findings indicate that speakers consistently reduced their rate of speech when using simultaneous communication, but did not violate these specific temporal rules of English important for consonant and vowel perception.

Humans↗
PubMed1992

Spectral study of deviant resonance in the speech of women who are deaf.

In a previous radiographic study of 4 deaf women, some aberrant features in vocal tract configuration were identified for vowels produced with excessive pharyngeal resonance. These features included neutralization of tongue position, elevation of the hyoid, and a retraction of the tongue, associated with a deflection of the epiglottis in the lower pharynx. The vowels, produced simultaneously with X-ray exposure, were analyzed spectrographically to study acoustic correlates of the vocal tract deformation. Comparisons of the formants for vowels /i/ /u/ and /a/ produced by the deaf women with mean formant values for these vowels produced by normal-hearing women revealed no consistent pattern of second-formant deviation. Formant structure evaluated on isovowel lines disclosed consistent neutralization of vowels, with F2 values clustering in the 1500-2100 Hz frequency range, which is attributed to the observed restricted horizontal movements of the tongue within the oral and pharyngeal cavities. If such restrictions affect the production of all vowels, a lower F2 might be assumed for the front vowels, which normally have a high F2; a higher F2 frequency would be anticipated for back vowels, which normally have a low F2. The limited sample studied supports this assumption.

Adult↗
PubMed1992

How we improved turn around time through voice-communication technology.

This hospital phlebotomy team tackled their age-old turn around time (TAT) problem by implementing a technology that is becoming commonplace in a variety of businesses. Through the use of two-way communication headsets, this hospital laboratory significantly reduced TAT, improved service perceptions by the medical and nursing staffs, and diminished stress levels of the venipuncture team.

Blood Specimen Collection↗
PubMed1989

Articulatory dimensions of hearing-impaired speakers' intelligibility: evidence from a time-related aerodynamic, acoustic, and electroglottographic study.

Regression and principal components analyses were employed to study the relationship between 30 aerodynamic speech parameters and the speech intelligibility of 40 severely to profoundly hearing-impaired speakers. Regression analysis on the original 30 aerodynamic variables revealed that speech intelligibility was predicted by a cognate-pair voice onset-time difference measure and a measure of the stability of the volume-velocity rise time. Principal components analysis of the 30 independent variables derived seven factors that accounted for 84.3% of the variance in the original 30 parameters. Subsequent regression analysis using the seven factors as predictor variables revealed four factors with independent relationships to speech intelligibility. These included a factor that reflected cognate-pair voice onset-time distinctions, a factor that reflected cognate-pair peak volume-velocity distinctions, and two other factors, which reflected production stability of temporal distinctions between cognate pair members.

Adult↗
PubMed1989

Effect of maternal rubella on hearing and vision: a twenty year post-epidemic study.

Three years of research conducted at NTID beginning in 1984 examined the hearing and vision characteristics of two groups of deaf college students. All 242 students studied received complete audiometric assessments and ophthalmological examinations. Of those students examined, 104 were known to be deaf as a result of maternal rubella (congenital rubella syndrome (CRS) group). The remaining 138 (non-CRS group) became deaf for a variety of other reasons. No significant differences were found between groups in puretone thresholds for frequencies measured at octave intervals from 250 thru 8000 Hz. There were, however, significant differences between the two groups relative to their vision characteristics. Seven visual pathologies or resulting conditions were found to be more prevalent with the CRS population. Among them were 38 cases of amblyopia which might have been prevented with early intervention. The various implications of this problem are discussed.

Adolescent↗
PubMed1987

Orosensory perception and articulatory proficiency in hearing-impaired adults.

Articulation errors and intelligibility of rated speech of 75 hearing-impaired young adults were compared to their errors on a test of orosensory perception. Analysis indicated no significant correlations between articulation, intelligibility of speech, and orosensory perception when total errors were compared. Some significant relationships were evident, however, for types of error. In addition, orosensory perception errors were compared with degree of hearing loss and history of use of amplification. These results indicated no significant relationships between the communication characteristics and total orosensory perception errors; however, when types of orosensory perception errors were compared, several significant relationships were evident. In general, present results may be useful in the development of appropriate remediation strategies for use by speech-language pathologists working with hearing-impaired persons.

Adult↗
PubMed1986

Consonant influences on vowel duration as a function of speech intelligibility for hearing-impaired individuals.

The purpose of this investigation was to study the effects of consonant environment on vowel duration for normally hearing males, hearing-impaired males with intelligible speech, and hearing-impaired males with semi-intelligible speech. The results indicated that the normally hearing and intelligible hearing-impaired speakers exhibited similar trends with respect to consonant influence on vowel duration; i.e., vowels were longer in duration, in a voiced environment as compared with a voiceless, and in a fricative environment as compared with a plosive. The semi-intelligible hearing-impaired speakers, however, failed to demonstrate a consonant effect on vowel duration, and produced the vowels with significantly longer durations when compared with the other two groups of speakers. These data provide information regarding temporal conditions which may contribute to the decreased intelligibility of hearing-impaired persons.

Acoustic Stimulation↗
PubMed1985

Acoustic characteristics of vocal tension/harshness in the speech of the hearing impaired.

The purpose of this investigation was to calculate, from vowels in continuous speech, the signal-to-noise ratio (S/N ratio) and average fundamental vocal frequency (F0) for hearing-impaired young adults who demonstrated varying degrees of vocal tension/harshness, and to correlate these acoustic measures with the degree of perceived, vocal tension/harshness. Subjects for this investigation consisted of 20 hearing-impaired males and 20 hearing-impared females who ranged in degree of tension/harshness from severe to normal/relaxed. S/N ratios and F0s were calculated, using a computer analysis program, from audio recordings of the speakers' reading of the first two sentences of the Rainbow Passage. The results indicated significant correlations between S/N ratios and degree of perceived tension/harshness, as well as between the average F0s and perceived tension/harshness. The clinical implications of these objective acoustic measures are discussed.

Adult↗
PubMed1985

Acoustic dimensions of hearing-impaired speakers' intelligibility.

Regression and principal components analyses were employed to study the relationship between three measures of speech intelligibility and 12 segmental, prosodic, and hearing ability parameters in 20 severely to profoundly hearing-impaired speakers. Regression analyses on the original 12 parameters revealed that cognate pair voice onset time differences and mean sentence duration strongly predicted speech intelligibility based on readings of isolated word and contextual speech material. A principal components analysis derived four factors that accounted for the majority of the variance in the original 12 parameters. Subsequent regression analyses using the four factors as predictor variables revealed two factors with strong relationships to the speech intelligibility measures. One factor primarily reflected segmental production processes related to the temporal and spatial differentiation of phonemes, whereas the other factor reflected prosodic features and production stability. These results are consistent with prior research that suggests independent primary and secondary roles for segmental and prosodic speech characteristics, respectively, in determining intelligibility in severely to profoundly hearing-impaired speakers.

Adult↗
PubMed1984

Mechanics of vocal fold vibration and laryngeal articulatory gestures produced by hearing-impaired speakers.

The purpose of this study was to gain a better understanding of how abnormal laryngeal mechanical valving actions might contribute to excessive air volume expenditures during the speech of the deaf. High-speed laryngeal film and high-quality acoustic data were collected simultaneously from two normally hearing and four hearing-impaired adults. Results indicate that hearing-impaired speakers (a) may be unable to control the intrinsic laryngeal musculature which maintains periodic vocal fold oscillation, and (b) may exhibit inappropriate positioning of laryngeal structures during speech production.

Adult↗
PubMed1984

Vibratory patterns of the vocal folds during pulse register phonation.

The purpose of the present study was to investigate the vibratory patterns of the vocal folds during pulse register phonation. Glottal area-time functions were calculated from three high speed laryngeal films (4000 frames/second) obtained during phonation of the schwa vowel in pulse register by a normally hearing and speaking adult female. The results for the first film indicated that each of 35 consecutive vibratory cycles of the vocal folds consisted of a single opening/closing gesture followed by a lengthy closed phase. The analysis of the second film revealed that each of 33 consecutive vibratory cycles consisted of a double opening/closing vocal fold pattern, followed by a long closed phase. For the third film, the results indicated that each of 26 consecutive vibratory cycles of the vocal folds consisted of either a double or triple opening/closing gesture followed by a lengthy closed period. From these data, it appears that one of the physiological descriptors of pulse phonation is multiple, as well as single, vocal fold vibratory patterning.

Adult↗
PubMed1983

Integrated spoken and written English instruction for the hearing-impaired student.

This study was designed to investigate the effect of integrated instruction in both spoken and written English on oral expression of hearing-impaired persons. Twenty-five hearing-impaired young adults were enrolled in English courses that focused on reading and writing skills only (control group) or on reading, writing, and complementary oral language instruction (experimental group). The experimental group demonstrated significant improvement in grammatical correctness of spoken English and in speech intelligibility, while the control group failed to demonstrate a significant improvement in these areas.

Hearing Disorders↗
PubMed1983

Airflow characteristics of fricative consonants produced by normally hearing and hearing-impaired speakers.

The purpose of this study was to investigate the rates of airflow for fricative consonants produced by normally hearing speakers and by hearing-impaired speakers who varied in degree of hearing loss and speech intelligibility. Subjects consisted of 20 normally hearing adults (10 men and 10 women), 20 moderately-to-severely hearing-impaired adults with intelligible speech (10 men and 10 women), and 20 profoundly hearing-impaired adults with semi-intelligible speech (10 men and 10 women). Average airflow rates were obtained for the fricatives /s/, /z/, /f/, and /v/ in CV and VCV syllables. In general, it was found that normally hearing, intelligible hearing-impaired, and some semi-intelligible hearing-impaired speakers produced voiceless fricatives with substantially greater airflow rates than they produced voiced cognates. The data also revealed that both male and female semi-intelligible hearing-impaired speakers produced fricatives in the CV context with greater amounts of airflow and fricatives in the VCV environment with less airflow than did the normally hearing and intelligible hearing-impaired speakers. Further, the male and female semi-intelligible hearing-impaired speakers failed to demonstrate the trend, as exhibited by the other speakers, for lingua-alveolar fricatives to be produced with greater air flow than the labiodental fricatives. The data from this investigation provide additional evidence to support the assumption that some hearing-impaired speakers fail to control and coordinate the biomechanical aspects of speech properly.

Adult↗