bluuebunny/crossref_metadata_2025 huggingface dataset:
Recruitment Thresholds of Lower-Lip Motor Units with Changes in Movement Direction
Authors: McClean Michael D.
Published: July 2014

Recruitment threshold may provide a useful measure for understanding the functional organization of speech muscles. The objective of the present study was to describe the recruitment thresholds of orbicularis oris inferior (OOI) and mentalis (MENT) motor units with changes in the direction of lower lip movement. Three subjects produced slow ramp displacements of the lower lip in three directions while simultaneous single motor unit recordings were obtained. Analysis was performed on 28 OOI units and 20 MENT units. The OOI motor units had their lowest recruitment thresholds for anterior lip movements, and the MENT units had their lowest thresholds for superior movements. In general, motor unit recruitment order was fixed and recruitment thresholds remained proportional with changes in the direction of movement. There was one instance of a recruitment order reversal in a pair of MENT motor units.
Magnitude Estimation of Loudness II
Authors: Knight Kimberly Keller , Margolis Robert H.
Published: July 2014

Because clinical methods most commonly used for assessing loudness are indirect measures that require one normal or near normal ear, loudness perception has not been studied thoroughly in listeners with symmetrical hearing loss. In this investigation, loudness perception was studied in three groups of listeners: normal listeners, listeners with asymmetrical sensorineural hearing loss, and individuals with bilaterally symmetrical hearing impairment due to presbycusis. In Experiment 1, a Magnitude Estimation of Loudness (ME) technique was compared to Alternate Binaural Loudness Balance (ABLB) results for subjects with asymmetrical hearing impairment. Results indicate that ME and ABLB measurements produce similar evidence of abnormally rapid growth of loudness in asymmetrically impaired listeners. In Experiment 2, loudness growth in individuals with normal hearing or with presbycusic hearing impairment was determined from ME measurements. Although presbycusic subjects tended to have steeper loudness functions than normal subjects, the differences did not reach statistical significance except at 6000 Hz, suggesting that, as a group, presbycusic listeners display little, if any, recruitment of loudness.
Symbolic Play in Normal and Language-Impaired Children
Authors: Terrell Brenda Y. , Schwartz Richard G. , Prelock Patricia A. , Messick Cheryl K.
Published: July 2014

The symbolic play of 15 normally developing (CA, 16–22 months) and 15 language-impaired children (CA, 32–49 months), whose productive language skills were at the single-word utterance level, was compared. Symbolic play was assessed formally through the Symbolic Play Test and informally through the observation of spontaneous play. The language-impaired children were found to be developmentally advanced when compared to the language-matched normal children in the level and direction of their symbolic play. Relative to age norms, however, the language-impaired children evidenced deficits in symbolic play. Thus, their linguistic and symbolic play abilities were not equally impaired. These findings are discussed in terms of their implications for the relationship between symbolic play and language and for the nature of specific language impairment.
Some Environmental Factors and Hypotheses for Stuttering in Families with Several Stutterers
Authors: Cox Nancy J. , Seider Robin A. , Kidd Kenneth K.
Published: July 2014

Individuals in families with several stutterers (five or more) and individuals in families with no stutterers were the basis of abroad study designed to elucidate both genetic and nongenetic factors relevant to stuttering. In order to examine both nongenetie hypotheses regarding the etiology of stuttering as well as enviromnental factors possibly predisposing to stuttering, data were collected using two structured case-history interviews .and four self-report inventories. We were unable to identify prenatal, developmental, or medical factors that distinguish stutterers from their nonstuttering family members. Further, we found no.evidence of (a) anxiety levels differing among stutterers, their nonstuttering family members, and nonstuttering controls; (b)familial attitudes toward speech differing between nonstuttering family members and those of nonstuttering controls; or (c) ratings of parental behavior or children's traits which distinguished stutterers from nonstuttering family members.
Simplification of /s/ + Stop Consonant Clusters
Authors: Catts Hugh W. , Kamhi Alan G.
Published: July 2014

This longitudinal study examined individual patterns and changes in /s/ + stop cluster simplifications of six normally developing children. Subjects produced selected words containing initial voiced and voiceless stops and /s/+ stop clusters at monthly intervals. Speech samples were transcribed phonetically, and voice onset times (VOT) of the stop consonants were measured. The results revealed that subjects reduced clusters most frequently to stop consonants with short-lag VOTs. However, two children also occasionally employed prevoicing, and one subject used long-lag VOTs in cluster-reduced stops. Because cluster-reduced stops and voiced singleton stops were generally produced with similar VOTs, it was concluded that subjects represented clustered stops most frequently as phonemically voiced.
Initial Iowa Results with the Multichannel Cochlear Implant from Melbourne
Authors: Tyler Richard S. , Lowder Mary W. , Otto Steven R. , Preece John P. , Gantz Bruce J. , McCabe Brian F.
Published: July 2014

Two subjects who use the Melbourne multichannel cochlear implant were studied. Live-voice word, consonant, and vowel recognition tests, and a speech-tracking task were administered at regular intervals during the first 90 days after implantation. Results indicated 30-50% correct recognition of vowels (given 9 alternatives) and about 30-60% correct recognition of consonants (given 12 alternatives). Speech tracking showed from two to three times faster rates with the implant and vision compared to a vision-alone condition. After 3-4 months of implant experience, a number of recorded tests from the Minimal Auditory Capabilities battery and the Iowa Cochlear-Implant tests were then administered. These results indicated about 80% recognition of everyday sounds in a five-choice closed-set condition and about 50% recognition of everyday sounds in an open-set condition. The subjects were 50% correct at identifying the accented words in a sentence and about 50% correct at determining the number of syllables in a word. One subject was unable to recognize a sentence as a statement or a question. Background noise (+10 dB S/N) reduced their performance on a four-choice spondee test to chance. Both subjects were able to identify a sound as either a voice or a modulated noise at 95% correct, and both could recognize speaker sex at 95% correct. Neither could discriminate whether two (successive) sentences were spoken by the same speaker or by two different speakers. Remarkably, one subject identified 45% and the other 85% of the words in sentences that were preceded by a contextual picture using sound alone. One subject identified 13% of the words in sentences in sound alone even without contextual information.
Production of Intonation and Contrastive Stress in Electrolaryngeal Speech
Authors: Gandour Jack , Weinberg Bernd
Published: July 2014

Acoustical investigations of intonation and contrastive stress patterns in speech produced with electronic artificial larynges were completed. High-quality tape recordings of sentences spoken by 4 normal speakers, 3 users of the Western Electric 5A electrolarynx, and 2 users of the Servox electrolarynx were subjected to acoustic analysis. All electrolarynx users distinguished stressed from unstressed syllables by varying the duration of syllables and contiguous pauses. One Western Electric 5A speaker also controlled fundamental frequency. This speaker distinguished statements from questions by varying the rate and extent of the initial rising portion of fundamental frequency contours. Findings are interpreted in relation to their implications for clinical intervention and in terms of suggestions for improved design of artificial larynges.
Prediction of Contextual Speech Intelligibility from Isolated Word Intelligibility Measures
Authors: Schiavetti Nicholas , Sitler Ronald W. , Metz Dale Evan , Houde Robert A.
Published: July 2014

The purpose of this study was to evaluate the efficacy of two nonlinear formulae posited by Boothroyd (1978) for prediction of contextual intelligibility from measures of isolated word intelligibility with four different sets of speech intelligibility data. Both of Boothroyd's formulae, P
c
= 1 - (1 ? P
i
)
2
and P
c
= 1 - (1 ? P
i
)
1.5 (1 + Pi)
, provided excellent fit of measured contextual intelligibility with predicted contextual intelligibility for all sets of data. Attempts to improve correlation coefficients between measured and predicted contextual intelligibility by iterating Boothroyd's suggested exponents did not significantly improve the predictive ability of the original formulae.
Variability of Lip and Jaw Movements in Children and Adults
Authors: Sharkey Susan G. , Folkins John W.
Published: July 2014

The development of speech motor skill was studied by measuring the variability of lower lip and jaw movements. Groups of five adults, and children at ages 4, 7, and 10 years produced [mæ] and [bæ] 20 times each. The duration of lip-opening movements, jaw-opening movements, lip-open postures, jaw-open postures, and the timing between the onset of lower lip opening and jaw opening decreased in variability between the child and adult groups. No significant differences were observed in the variability of these measures across the child groups. The variability of lower lip displacement decreased significantly between the 4-year-old and 7-year-old groups, but not between any other age groups. Jaw displacement variability did not change significantly between any groups. No significant differences in variability were found between [bæ] and [mæ]. It is hypothesized that different developmental motor processes affect the variability of speech movements at early, intermediate, and older ages.
Relationships between the Perception of Nasalization and Speech Movements in Speakers with Cleft Palate
Authors: Karnell Michael P. , Folkins John W. , Morris Hughlett L.
Published: July 2014

The purpose of this study was to examine the relationships between several temporal measures of speech movements and perceived nasalization in speakers with cleft palate. Four adult subjects with repaired cleft palate were filmed using high-speed (100 frames/s) cinefluorography as they produced target syllables embedded in a carrier phrase. Perceived nasalization of each extracted acoustic target syllable was rated by 18 trained judges. Movements of the tongue tip, tongue dorsum, jaw, velar knee, velar tip, and posterior pharyngeal wall were plotted over time. Time of movement onsets and movement offsets was identified from the plots. Voice onset and offset times were identified from the synchronized acoustic recordings. The findings indicate that normally expected velopharyngeal movements occurred near the time of jaw-lowering onset during nasalized CVC and CVN productions in two subjects who were judged to exhibit high levels of nasalization. The other two subjects showed no velopharyngeal movements during the CVC production. It is speculated that velopharyngeal movements normally expected in CVC utterances may be avoided by some speakers with cleft palate in order to minimize perceptible nasalization.
Prephonatory Laryngeal and Chest Wall Dynamics
Authors: Cavallo Stephen A. , Baken R. J.
Published: July 2014

The timing of prephonatory movements of the larynx, rib cage, and abdomen was examined in order to gain insight into the contribution of the vocal folds to the posturing of the chest wall. A simple stimulus-response paradigm was used in eliciting brief utterances—/α/ and /hα/—from six adult males. Chest wall movements were observed using mercury strain gages while simultaneous electroglottographic and airflow records provided information about vocal fold behavior. Independence of prephonatory laryngeal and chest wall behavior was demonstrated. Laryngeal adjustment preceded the start of vocal fold oscillation by a constant amount of time, whereas the time of onset of the chest wall adjustment varied as a function of the utterance type. The qualitative characteristics of prephonatory chest wall posturing were unaffected by altering glottal configuration requirements. Rib cage enlargement occurred during postural adjustment while the vocal folds were abducted (in preparation for/h/). This implies that rib cage enlargement during prephonatory chest wall posturing was not a passive response to abdominal compression.
Constructive Comprehension Abilities Exhibited by Language-Disordered Children
Authors: Weismer Susan Ellis
Published: July 2014

Constructive comprehension abilities were compared in a group of 12 language-disordered children (second graders) and two groups of children acquiring language normally (12 second graders matched to the language-disordered subjects on nonverbal cognitive skills and 12 kindergartners matched on language comprehension). Differences were examined in proficiency of the children in constructing spatial and causal inferences associated with short stories presented in a Verbal Task and Picture Task. The language-disordered group scored significantly lower on inference items than the cognitively matched control group of second graders on both tasks. A conditional analysis indicated that even when the language-disordered subjects appropriately answered the relevant premise items, they were significantly less likely than the second-grade controls to correctly respond to inference items on both tasks. There was no significant difference between the language-disordered and kindergarten children for either the overall or conditional analysis. The finding that language-disordered children evidenced difflculty in inference construction for both verbal and pictorial material was interpreted as being indicative of a cognitive deficit.
Evaluation of Speech Production of the Hearing Impaired
Authors: Boothroyd Arthur
Published: July 2014

The speech production performance of 16 hearing-impaired subjects (thresholds 82-110 dB HL) was measured using both experienced and inexperienced listeners. Four types of measure were obtained: (a) score on a forced-choice test requiring the production of eight segmental contrasts, (b) recognition probability for phonemes produced in consonant-vowel-consonant (CVC) words, (c) recognition probability for CVC words produced in a simple carrier phrase, and (d) recognition probability for words produced in sentence context. The experienced listeners gave higher scores than did the inexperienced listeners, but the magnitude of the effect decreased with decreasing linguistic redundancy in the test material, falling to only 1.3 percentage points for the forced-choice test. The pattern of performance across the eight contrasts of the forced-choice test changed significantly from subject to subject. Performance on the contrast test accounted for 70% of the variance in the scores on the sentence test. The results demonstrate that forced-choice tests can be used to provide speech production measures that are virtually independent of listener experience, that provide analytic detail about an individual's production of phonetic contrasts, and that are reasonably predictive of the intelligibility of speech produced in more natural communicative settings.
Tympanometric and Acoustic-Reflex Studies in Neonates
Authors: Sprague Barbara H. , Wiley Terry L. , Goldstein Robert
Published: July 2014

Tympanograms and acoustic reflexes for a broadband noise and for a 1000-Hz tone were measured in normal neonates. Notched tympanograms were typical of neonatal ears for a 220-Hz probe tone. A single-peaked tympanogram was most characteristic for a probe frequency of 660 Hz. Ipsilateral and contralateral acoustic reflexes were present more frequently for a 660-Hz probe tone compared to a 220-Hz probe tone, but acoustic-reflex thresholds were not significantly different between probe tones. As with adults, acoustic-reflex thresholds for the noise were significantly lower than for the tone, and ipsilateral reflex thresholds were lower than contralateral reflex thresholds. Reliability of acoustic-reflex and tympanometric measures was high. Age change from 2 to 4 days had no significant effect on tympanometric or acoustic-reflex characteristics. There was no apparent relation between tympanometric pattern and acoustic-reflex characteristics.
Word Recognition Performance with Modified CID W-22 Word Lists
Authors: Runge Cheryl A. , Hosford-Dunn Holly
Published: July 2014

Abbreviated CID W-22 lists were administered to large groups of normal and hearing-impaired listeners to test the hypothesis, that fewer, judiciously chosen items can be used to test word recognition without compromising test accuracy. Data were analyzed by comparing each subject's performance on half- and 10-word lists to full-list scores. Sensitivity and specificity for various sublists and for several pass/fail criteria were calculated. Results show that fewer than the traditional 50 items can be used in word recognition test procedures if the words are sufficiently difficult and strict passing criteria are employed. We recommend terminating testing after 10 words if no errors occur and after 25 words if there are no more than four errors. Otherwise, a full 50-item list should be administered.
Empty Speech in Alzheimer's Disease and Fluent Aphasia
Authors: Nicholas Marjorie , Obler Loraine K. , Albert Martin L. , Helm-Estabrooks Nancy
Published: July 2014

Fourteen measures of empty speech during a picture description task were examined in four subject groups—patients with Alzheimer's dementia, Wernicke's aphasias, anomic aphasias, and normal controls—to discover if these groups could be distinguished on the basis of their discourse. Patients with Alzheimer's dementia were distinguished from patients with Wernicke's aphasia by producing more empty phrases and conjunctions, whereas patients with Wernicke's aphasia produced more neologisms, and verbal and literal paraphasias. The demented patients shared many empty speech characteristics with patients with anomic aphasia. Naming deficits, as measured by confrontation naming tasks, did not correlate with empty discourse production. Our findings may be useful clinically for distinguishing these different patient groups.
Magnitude Estimation of Loudness III
Authors: Margolis Robert H.
Published: July 2014

Aided and unaided loudness functions for narrow-band noise stimuli were obtained from hearing-impaired listeners with a magnitude estimation procedure. A comparison of aided loudness functions with those obtained from normal-hearing subjects suggests that the hearing aids did not restore normal loudness relations among the spectral components of speech stimuli. Instead, aided loudness functions tend to reflect an interaction between the abnormal loudness growth that frequently characterizes sensorineural hearing loss and the saturation characteristics of the hearing aid.
Phonetic Speech Perception Deficits in Dyslexia
Authors: Lieberman Philip , Meskill Robert H. , Chatillon Mary , Schupack Helaine
Published: July 2014

Adult developmental dyslexics showed deficits in the identification of the vowels of English when the sole acoustic cues were steady-state formant frequency patterns. Deficits in the identification of place of articulation of the English stop-consonants [b], [d] and [g] in syllable-initial position were also observed. The average vowel error rate was 29%. The average consonantal error rate was 22%. These error rates are significantly different from those of nondyslexic control groups (p < .01). No single deficit characterized the entire group of dyslexic subjects. The pattern of errors with respect to place of articulation also varied for different groups of subjects. Three dyslexics have high vowel error rates and low consonantal error rates. The data are consistent with the premise that dyslexic subjects may have different perceptual deficits rather than a general auditory deficit involving the rate at which they can process perceptual information. The clinical histories of the present subjects suggest genetic transmission of these speech perception deficits. The presence of genetic variation in the biological substrate relevant to the perception of human speech should be further explored.
Development of Print Awareness in Language-Disordered Preschoolers
Authors: Gillam Ronald B. , Johnston Judith R.
Published: July 2014

This study examined print awareness and related oral language abilities in language-disordered and normally developing preschoolers. Twenty subjects, ages 3:1 to 6:5 (years:months), were shown high frequency environmental print in four conditions varying in the amount of non-print information present in the print setting. They were asked to match the print to the object that it signified and to provide verbal labels for the same objects. Results indicated that normal-language children were responding meaningfully to print settings that contained reduced non-print cues while the language-disordered subjects were not. General language ability was correlated with print awareness, but knowledge of specific oral lexemes was not necessary for accurate print responses. Parent questionnaire data suggested that group differences did not result from differential prior experience with the print items. Results are discussed with reference to hypothesized relationships between oral and written language.
Tinnitus Induced by Tones
Authors: Kemp Simon , Plaisted Ian D.
Published: July 2014

Noisy sounding tinnitus was induced in 11 normally hearing subjects following monaural presentation of intense pure tones. The sensation level of a comparison noise, matched in loudness to the tinnitus by the subjects, was found to increase first rapidly and then slowly before dying away within about 90 s. The peak level of the tinnitus increased with the level of the inducing tone but was unaffected by its duration or frequency; the duration of the tinnitus was positively related to the frequency but not to the level or duration of the tone. Temporary threshold shift measured with pulsed noise generally occurred after, rather than during, the tinnitus. Substantial individual differences, particularly in the duration of the tinnitus, were apparent.
Differential Fine Force Control of the Upper and Lower Lips
Authors: Barlow Steven M. , Netsell Ronald
Published: July 2014

From a review of the literature, it was hypothesized that the upper lip and lower lip are differentially controlled by separate, but interacting, neuronal connectivities. A normal data base was developed for select measures of fine force control occurring within physiologic levels presumably involved in speech production. Fine force control in the lower lip was found to be significantly more stable, and recruited at higher rates than the upper lip. Explanations are presented for the lower lip superiority on these measures and observations are made concerning the use of these rudimentary physiologic measures in studies of the dysarthrias.
Visual Feedback and Lip-Positioning Skills of Children with and without Impaired Hearing
Authors: Fletcher Samuel G.
Published: July 2014

Interplay between visual feedback and lip-positioning skill was studied in 10 5- to 14-year-old children with normal hearing and 10 with severe to profound hearing impairment. With visual feedback, the subjects in both groups had similar response times and accuracy in matching six visually specified lip separation "targets." Special skill in processing visual information by the hearing-impaired subjects was suggested by higher velocities of lip movement toward the targets and shorter latencies in reaching the goal positions. In the responses of the hearing children, lip-closing movements were executed more accurately than opening movements both with and without visual feedback. In general, the findings showed that, given visually displayed lip-position targets and feedback from positioning actions, children can achieve the targets with high accuracy regardless of hearing status or prior speaking experience.
Digital Inverse Filtering for Linguistic Research
Authors: Javkin Hector Raul , Antoñanzas-Barroso Norma , Maddieson Ian
Published: July 2014

To enable differences in modes of glottal vibration to be studied, glottal air volume velocity waveforms can be recovered from speech recordings by inverse filtering. Most previous published work in this area has made use of analog filters. Digital inverse filters offer many advantages, including the ability to change filter settings to match changing vocal tract filter functions. Although the theory and many of the methods necessary for digital inverse filtering have been described in the literature, a straightforward description of the entire process has been lacking. The digital inverse filtering process developed for linguistic research at the UCLA Phonetics Laboratory is described in detail in this paper, with the intention of facilitating such work at other institutions.
Word and Feature Identification by Profoundly Deaf Teenagers Using the Queen's University Tactile Vocoder
Authors: Brooks P. L. , Frost B. J. , Mason J. L. , Gibson D. M.
Published: July 2014

The experiments described are part of an ongoing evaluation of the Queen's University Tactile Vocoder, a device that allows the acoustic waveform to be felt as a vibrational pattern on the skin. Two prelingually profoundly deaf teenagers reached criterion on a 50-word vocabulary (live voice, single speaker) using information obtained solely from the tactile vocoder with 28.5 and 24.0 hours of training. Immediately following word-learning experiments, subjects were asked to place 16 CVs into five phonemic categories (voiced & unvoiced stops, voiced & unvoiced fricatives, approximants). Average accuracy was 84.5%. Similar performance (89.6%) was obtained for placement of 12 VCs into four phonemic categories. Subjects were able to acquire some general rules about voicing and manner of articulation cues.
Reflex Responses in Human Jaw, Lip, and Tongue Muscles Elicited by Mechanical Stimulation
Authors: Weber Christine M. , Smith Anne
Published: July 2014

Reflex responses in human jaw, lip, and tongue muscles were elicited with brief, innocuous mechanical stimuli. Stimuli were applied to the masseter (and overlying tissue), the lower lip vermilion, and the tongue dorsum. Reflex responses occurred in masseter, orbicularis oris inferior, and genioglossus muscles upon direct stimulation of the sites associated with each of these muscles. In contrast, reflex responses to stimulation of "distant" sites occurred almost exclusively in masseter; that is, stimulation of the lip and tongue produced responses in masseter, but, stimulation of jaw muscle spindle afferents and overlying cutaneous receptors had no observable effect on activity in genioglossus or orbicularis oris inferior muscles. It could be hypothesized that the motoneuron pools controlling jaw muscles are more sensitive to synaptic inputs generated by reflex pathways originating in other structures. The sensitivity of the masseter muscle to inputs from the lip and tongue may serve to link these structures functionally.
Cohesion in the Discourse of Normal and Head-Injured Adults
Authors: Mentis Michelle , Prutting Carol A.
Published: July 2014

Cohesion strategies used by 3 normal and 3 head-injured adults were examined in both conversational and narrative conditions. Two major findings emerged. First, the head-injured subjects used different cohesion patterns from the normal adults in both conditions. Second, both groups used different cohesion patterns in the conversational and narrative conditions. The study highlights the importance of viewing the language of head-injured adults within the context of discourse. Testing the language system through narrative as well as conversational discourse is important since both conditions are characterized by their own distinctive internal structure and organization.
Effect of Formant Transition Rate on the Differentiation of Synthesized Child and Adult /w/ and /r/ Sounds
Authors: Ohde Ralph N. , Sharf Donald J.
Published: July 2014

The purpose of this research was to assess the perceptual effects of a range of second (F2) and third (F3) formant transition rates that occur naturally in the production of /w/ and /r/ by children and adults. Synthesized CV continua that varied in the second (F2) and third (F3) formant onset frequencies between values appropriate for /w/ and /r/ were used as stimuli. Subjects participated in four experimental conditions that involved changing the rate of transition of either F2 or F3 by varying the duration of the transition between the glide onset and an /e/ vowel nucleus for child and adult stimuli. In each condition, the transition rates of the /w/-endpoint stimulus, the /r/-endpoint stimulus, and at least one of the midpoint stimuli were varied across values appropriate for /w/ and /r/. Mean ratings of the stimuli were compared to test the predictions that /w/ perception increases with increased F2 transition rate and increases with decreased F3 transition rate. The results were as follows: (a) one of the 10 comparisons for the child F2 stimuli was significant, but it involved a change opposite to the predicted direction; (b) four of the six comparisons for the child F3 stimuli were significant, but they involved changes opposite to the predicted direction; (c) 14 comparisons of adult F2 stimuli were significant, but 12 of these 14 comparisons involved changes opposite to the predicted direction; and (d) four of the six comparisons for the adult F3 stimuli were significant, but none of them involved changes in the predicted direction. Only one of all the comparisons involved a significant change in rating between the /w/ and /r/ categories.
Some Technical Considerations in Voice Perturbation Measurements
Authors: Titze Ingo R. , Horii Yoshiyuki , Scherer Ronald C.
Published: July 2014

The maximum theoretical quantization noise (shimmer and jitter) for digital recording systems is estimated and compared with normal vocal shimmer and jitter. Nine bits of resolution and 500 samples per cycle are needed to minimize the contaminating sampling noise without interpolation between samples. With interpolation, however, fewer than 100 samples per cycle can resolve jitter down to 0.1%. Low-pass filtering is not harmful unless peak-picking strategies are used, and the peaks are severely broadened by the low-pass filter. A window of at least 20 cycles is suggested, and multiple tokens of an utterance are necessary to obtain a stable mean for perturbation measures.
Formant Frequencies of Stuttered and Fluent Vowels
Authors: Prosek Robert A. , Montgomery Allen A. , Walden Brian E. , Hawkins David B.
Published: July 2014

The formant frequencies of 15 adult stutterers' fluent and disfluent vowels and the formant frequencies of stutterers' and nonstutterers' fluent vowels were compared in an F1-F2 vowel space and in a normalized F1-F2 vowel space. The results indicated that differences in formant frequencies observed between the stutterers' and nonstutterers' vowels can be accounted for by differences among the vocal tract dimensions of the talkers. In addition, no differences were found between the formant frequencies of the fluent and disfluent vowels produced by the stutterers. The overall pattern of these results indicates that, contrary to recent reports (Klich & May, 1982), stutterers do not exhibit significantly greater vowel centralization than nonstutterers.
Conversational Turn-Taking Violations in Mother-Child Interaction
Authors: Bedrosian Jan L. , Wanska Susan K. , Sykes Kim M. , Smith Anne J. , Dalton Beth M.
Published: July 2014

Conversational turn-taking violations and corresponding repair mechanisms in mother-child interaction were examined. Thirty mother-child dyads, with children ranging in age from 2:10 (years:months) to 6:3, were videotaped in a 10-min free play situation. The interactions were analyzed for several aspects of overlaps (i.e., simultaneous talking), including general characteristics, participant involvement, turn-taking repair mechanisms, topic characteristics, and communicative intent. Of the 246 overlaps identified, the majority Were single, nonconsecutive, and internal (Gallagher & Craig, 1982). Mothers interrupted significantly more than did the children. In terms of repair mechanisms, children exhibited a greater frequency of discontinuation of talking when the mothers interrupted than did the mothers for the comparable situation. Both within and following the majority of overlaps, mothers and children maintained the same topic. Utterances consisting of informative statements were interrupted more often than those consisting of requests. In general, mothers did not appear to be as facilitative of their children's turn-taking skills as they are for other pragmatic skills.
Amplitude Compression and Profound Hearing Loss
Authors: Boothroyd Arthur , Springer Nancy , Smith Lynn , Schulman Jane
Published: July 2014

Nine subjects with prelingually acquired, sensorineural, hearing loss were given a three-interval, forced-choice, test of speech pattern contrast perception under two amplification conditions. The first involved adjustment of the low and high frequency outputs of a two-channel Master Hearing Aid to each subject's highest comfortable level, but without compression of the short-term dynamic range of the signal. The second involved the additional compression of a 30 dB input range into the subject's dynamic range of hearing, as measured by the difference between speech awareness threshold and highest comfortable level, in each of the two channels. One of the subjects performed much better with compression than without. Among the other eight, however, there was a small but significant reduction of performance when compression was introduced. It is proposed that the one positive result is due to the increased audibility of speech cues made possible by amplitude compression. It is further proposed that the negative results are due mainly to the distortions of time-intensity cues introduced by amplitude compression. The results suggest that, in terms of potential access to meaningful speech cues, the addition of amplitude compression, to an otherwise optimize signal, is unnecessary, or even detrimental, for most profoundly deaf subjects, but could be beneficial for some.
A Comparison of Stutterers' and Nonstutterers' Affective, Cognitive, and Behavioral Self-Reports
Authors: Watson Jennifer Barber
Published: July 2014

This study compared stutterers' and nonstutterers' communication attitudes. A self-report inventory based on a tripartite attitudinal model was administered to 75 adult stutterers and 81 adult nonstutterers. Ratings of 39 items representing 13 situational subseales, or types of speaking situations, on four response scales reflecting behavioral, affective, and cognitive components and a frequency scale were obtained. Self-ratings of speech enjoyment and speech skills best discriminated stutterers and nonstutterers. However, these self-ratings were related for both stutterers and nonstutterers. Frequency of encountering speaking situations was related to enjoyment of speech for stutterers, but not for nonstutterers. Moreover, stutterers, unlike nonstutterers, believed that most people's enjoyment of speech was not related to most people's speech skills. Similarities and differences in stutterers' and nonstutterers' ratings of specific speaking situations were identified.
A Modified Speech Tracking Procedure as a Communicative Performance Measure
Authors: Matthies Melanie L. , Carney Arlene Earley
Published: July 2014

A modified speech tracking procedure was investigated to determine the effects of controlling connected discourse materials and of Specific prompting techniques on tracking rate and subjects' responses. In addition, comprehension was tested after subjects completed the tracking task. Two experiments were conducted with normally hearing subjects, one in which subjects tracked in an auditory plus noise condition and the second in which they tracked in a visual-alone condition. The results of these two experiments showed significant differences between tracking rates for controlled versus uncontrolled materials for both modalities, with higher tracking rates observed for the controlled materials. The use of specific prompting techniques reduced intertester variability in both modalities. Further, results indicated that comprehension ability and tracking skill are not perfectly related.
Vibrotactile Perception of Segmental Features of Speech
Authors: Carney Arlene Earley
Published: July 2014

This experiment compared the recognition performance of artificially deafened listeners for segmental stimuli presented through a single-channel tactile device and through a 24-channel vocoder. Both consonant and vowel stimuli were tested under visual only, tactile only, and visual + tactile conditions. Each subject received a pretest, eight 2-hr training sessions, and a posttest. Results indicated no significant differences between subjects' overall recognition performance with two different tactile devices. Analysis of consonant confusions showed that both devices transmit the features of voicing, manner, and place of articulation in a similar fashion. In contrast to an earlier study on suprasegmental features by Carney and Beachler (1986), these results do not support the notion that preservation of the waveform envelope of speech is necessary for the transmission of segmental features of speech. These results also suggest that tactile perception of segmental features may not be altered significantly by the tactile array chosen.
Unisensory and Bisensory Processing Skills of Children Having Misarticulations and Normally Speaking Peers
Authors: Hetrick R. Dennis , Sommers Ronald K.
Published: July 2014

The purpose of this investigation was to test the developmental delay hypothesis as a possible explanation for the existence of misarticulations in 7- and 8-year-old children. To accomplish this, 10 normally speaking children, 10 having mild misarticulations, and 10 children with severe misarticulations were administered unisensory and bisensory processing tasks. Unisensory tasks consisted of oral and manual form discrimination and auditory recall of word strings. Bisensory tasks were combinations of the unisensory ones and were of major interest, because this form of processing has been considered a test of children's CNS maturity. Results showed that children having misarticulations obtained lower scores than children with normal articulation on all bisensory tasks and had larger decrements from unisensory to bisensory tasks than control subjects. On unisensory tasks involving recall of word strings and manual form discrimination, differences were also found in favor of the control subjects. The results supported the hypothesis that delayed CNS development may coexist with misarticulations of 7- and 8-year-old children.
Phonemic Information Transmitted by a Multichannel Electrotactile Speech Processor
Authors: Blamey P. J. , Cowan R. S. C. , Alcantara J. I. , Clark G. M.
Published: July 2014

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.
Alternating Current at the Eardrum for Tinnitus Reduction
Authors: Kuk Francis K. , Tyler Richard S. , Rustad Nancy , Harker Lee A. , Tye-Murray Nancy
Published: July 2014

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 rain, 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.
Spasmodic Dysphonia, Whether and Where
Authors: Finitzo Terese , Freeman Frances ,   The Dallas Center for Vocal Motor Control
Published: July 2014

Two questions are addressed in this presentation and integration of experimental data from seven years of research. They are (a) is spasmodic dysphonia (SD) a neurologic disorder; and (b) if so, where in the nervous system does the dysfunction have its locus? The conclusion is that SD is a supranuclear movement disorder primarily, but not exclusively, affecting the larynx. For over 50% of the subjects, isolated, multifocal, cortical lesions can be identified, specifically in left frontal/temporal cortex (perisylvian region), medial frontal cortex, and right posterior temporal/parietal cortex. Twenty-five percent have mixed subcortical and cortical pathology. Seven percent manifest subcortical lesions alone. For 16%, neither cortical nor subcortical structural or functional lesions are identified. Three etiologic processes that could produce mild multiple cortical and subcortical lesions are closed head injury, multi-infarct microvascular disease, and exposure to neurotoxins. These processes are discussed with reference to the population studied.
The Effects of Emphasis on Passage Comprehension
Authors: Bean Carolyn , Folkins John W. , Cooper William E.
Published: July 2014

It may be inferred from reaction time studies that the location of emphasis on nouns and noun phrases facilitates their comprehension (understanding and memory). However, we know of no previous demonstration of improved passage comprehension in normal listeners associated with emphasis placement. The present experiment examined effects of emphasis on comprehension of 12 passages that were read aloud and tape recorded. Emphasis placement was varied by splicing sentences containing emphasized or nonemphasized noun phrases into passages without altering the wording of the passages. These passages, contrasting in emphasis, were presented to 60 listeners. Comprehension was measured with multiple-choice, recognition questions that required subjects to link ideas across sentences. Comprehension was accurate significantly more often when correct response alternatives had been emphasized (71%), than when incorrect alternatives had been emphasized (56%), or no emphasis occurred in passages (57%). Findings reflect enhanced comprehension of emphasized items in terms of their meaning links to other concepts presented in passages. Results support the pragmatic assumption that the role of emphasis is to delineate constituents important in discourse meaning.
The Bifrequency Binaural Interaction Component of the Auditory Brainstem Response
Authors: Fowler Cynthia G.
Published: July 2014

The binaural interaction component of the auditory brainstem response was investigated in three stimulus conditions, 1000-Hz tone pips to both ears, 3000-Hz tone pips to both ears, and 1000-Hz tone pips to the left ear and 3000-Hz tone pips to the right ear. A binaural interaction component was produced in all conditions in which the stimuli were presented in quiet and in broadband noise, suggesting that a frequency separation of 2000 Hz between ears can produce a fused image. Responses to the bifrequency stimuli in noise indicated the peak A of the binaural interaction component is not dependent solely on the slope of wave V because when the noise caused a dissociated binaural wave V, peak A was associated only with the trailing wave V.
The Perception of Rhythm and Word Boundaries in Noise-Masked Speech
Authors: Smith Mary R. , Cutler Anne , Butterfield Sally , Nimmo-Smith Ian
Published: July 2014

The present experiment tested the suggestion that human listeners may exploit durational information in speech to parse continuous utterances into words. Listeners were presented with six-syllable unpredictable utterances under noise-masking, and were required to judge between alternative word strings as to which best matched the rhythm of the masked utterances. For each utterance there were four alternative strings: (a) an exact rhythmic and word boundary match, (b) a rhythmic mismatch, and (c) two utterances with the same rhythm as the masked utterance, but different word boundary locations. Listeners were clearly able to perceive the rhythm of the masked utterances: The rhythmic mismatch was chosen significantly less often than any other alternative. Within the three rhythmically matched alternatives, the exact match was chosen significantly more often than either word boundary mismatch. Thus, listeners both perceived speech rhythm and used durational cues effectively to locate the position of word boundaries.
Masking of Tone Bursts by Modulated Noise in Normal, Noise-Masked Normal, and Hearing-Impaired Listeners
Authors: Humes Larry E.
Published: July 2014

Threshold of 4.6-ms tone bursts was measured in quiet and in the presence of a 100% sinusoidally amplitude-modulated speech-shaped noise. For the modulated-noise conditions, the onset of the tone burst coincided either with the maximum or the minimum modulator amplitude. The difference in these two masked thresholds provided an indication of the psychoacoustic modulation depth, or the modulation depth preserved within the auditory system. Modulation frequencies spanning the modulation spectrum of speech (2.5 to 20 Hz) were examined. Tone bursts were 500, 1400, and 4000 Hz. Subjects included normal listeners, normal listeners with a hearing loss simulated by high-pass noise, and hearing-impaired listeners having high-frequency sensorineural hearing loss. Normal listeners revealed a psychoacoustic modulation depth of 30–40 dB for the lowest modulation frequencies which decreased to about 15 dB at 20 Hz. The psychoacoustic modulation depth was decreased in the normal listeners with simulated hearing loss and in the hearing-impaired listeners. There was general agreement in the data, however, for the latter two groups of listeners suggesting that the normal listeners with hearing loss simulated by an additional masking noise provided a good representation of the performance of hearing-impaired listeners on this task.