bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of an Articulation-Index Based Model for Predicting the Effects of Adaptive Frequency Response Hearing Aids
Authors: Fabry David A. , Tasell Dianne J. Van
Published: August 2014

The Articulation Index (AI) was used to evaluate an “adaptive frequency response” (AFR) hearing aid with amplification characteristics that automatically change to become more high-pass with increasing levels of background noise. Speech intelligibility ratings of connected discourse by normal-hearing subjects were predicted well by an empirically derived AI transfer function. That transfer function was used to predict aided speech intelligibility ratings by 12 hearing-impaired subjects wearing a master hearing aid with the Argosy Manhattan Circuit enabled (AFR-on) or disabled (AFR-off). For all subjects, the AI predicted no improvements in speech intelligibility for the AFR-on versus AFR-off condition, and no significant improvements in rated intelligibility were observed. The ability of the AI to predict aided speech intelligibility varied across subjects. However, ratings from every hearing-impaired subject were related monotonically to AI. Therefore, AI calculations may be used to predict relative—but not absolute—levels of speech intelligibility produced under different amplification conditions.
Effects of Apparent Listener Knowledge and Picture Stimuli on Aphasic and Non-Brain-Damaged Speakers’ Narrative Discourse
Authors: Brenneise-Sarshad Robin , Nicholas Linda E. , Brookshire Robert H.
Published: August 2014

This experiment investigated whether aphasic adults’ assumptions regarding listener knowledge of the topic of discourse affects the content of their narrative discourse. Aphasic and non-brain-damaged adults told two stories about sequences of black-and-white line drawings in two conditions. In a knowledgeable listener condition, subjects told the stories to a listener while the subject and listener were looking at the pictures portraying the story. In a naive listener condition, subjects told the stories to a listener whom the subject had not met before, who did not have access to pictures about the stories, and who the subject was led to believe had no knowledge of the pictures upon which the stories were based. The differences in performance between non-brain-damaged and aphasic subjects were greater than the differences between listener conditions and between stories. Non-brain-damaged subjects produced significantly more words, more information, a greater percentage of words that communicated relevant and accurate information, and longer grammatical units than aphasic subjects did. There were no significant differences between non-brain-damaged and aphasic subjects in their use of four kinds of cohesive ties. Listener conditions and stories had few significant effects on non-brain-damaged or aphasic subjects’ performance, and the few statistically significant effects that were observed did not appear to be clinically important.
A Comparison of Young Stutterers’ Fluent Versus Stuttered Utterances on Measures of Length and Complexity
Authors: Gaines Natalie D. , Runyan Charles M. , Meyers Susan C.
Published: August 2014

This investigation attempted to clarify the relationship between stuttering in young children and the language factors of length and grammatical complexity. Sentences containing stutterings within the first few words, as produced by 12 stutterers (4–6 years old) in spontaneous conversational dyads, were analyzed for length and grammatical complexity. Results indicated that sentences in which an episode of stuttering occurred within the first three words were significantly longer and more complex than sentences that were free of perceptible stuttering and all other forms of fluency failure. Implications of these findings for the clinician are presented and discussed.
Development and Validation of an Instrument to Measure Occupational Stress in Speech-Language Pathologists
Authors: Fimian Michael J. , Lieberman R. Jane , Fastenau Philip S.
Published: August 2014

The Speech-Language Pathologist Stress Inventory (SLPSI) is a 48-item questionnaire adapted from the Teacher Stress Inventory (Fimian, 1988). Factor analyses of the responses of 626 speech-language pathologists revealed four stress source factors (Bureaucratic Restrictions, Time and Workload Management, Lack of Professional Supports, and Instructional Limitations) and two stress manifestation factors (Emotional-Fatigue Manifestations and Biobehavioral Manifestations). The internal consistency reliability of scales based on these factors ranged from .71 to .87, with .93 for the entire scale. Evidence for construct validity was found in moderate positive correlations between the scales of the SLPSI and the scales of the Maslach Burnout Inventory (MBI) (Maslach & Jackson, 1986). Stress and burnout subscale intercorrelations ranged from .10 to .82 (
p
<.01), and the correlation between stress strength and burnout frequency was .66 (
p
<.001).
The Effects of Sampling Conditions on Sentence Production in Normal, Reading-Disabled, and Language-Learning-Disabled Children
Authors: Masterson Julie J. , Kamhi Alan G.
Published: August 2014

This study explored the effects of contextual support, discourse genre, and the listener’s knowledge of information on syntactic and phonologic production and fluency. Subjects were language-learning-disabled, reading-disabled, and normal primary school children. Clause structure complexity, fluency, and grammatical and phonemic accuracy tended to be highest when children were discussing absent referents, providing explanations and stories, and giving unshared information. These effects were generally the same across all groups, although some effects were significant for only the language-learning-disabled children. Several explanations for these findings are considered.
Slow-to-Recover Brain-Injured Patients
Authors: Ansell Barbara J.
Published: August 2014

Approximately 10–20% of head injury survivors sustain extensive neurological damage and remain minimally or inconsistently responsive to stimuli for 3–6 months postinjury. These patients, designated as slow to recover (STR), may be candidates for sensory stimulation programs rather than traditional rehabilitation. Medical and insurance personnel have resisted referral and payment for treatment because of the lack of objective measures of progress, a theoretical basis for treatment, and evidence of treatment efficacy. A valid, reliable assessment tool has recently been developed (Western Neuro Sensory Stimulation Profile) that assesses low-level cognitive/communicative function and documents improvement in STR patients. This article addresses the theoretical rationale for treatment. Evidence from four areas—sensory deprivation, enriched environments, nervous system plasticity, and sensitive periods of neurodevelopment— suggests that sensory stimulation programs are potentially beneficial for STR patients. Speech-language pathologists are encouraged to study the recovery patterns of STR patients and to determine the efficacy of treatment strategies.
Spontaneous Narrative-Discourse Performance of Parents of Autistic Individuals
Authors: Landa Rebecca , Folstein Susan E. , Isaacs Crystal
Published: August 2014

The spontaneous narrative-discourse performance of parents of autistic individuals was compared to controls. The narratives of autism parents were similar in length to controls’ narratives but were less complex and less coherent. A subgroup of autism parents produced either skeletal or rambling narratives that were not characterized by the type of simplifications that are reported to facilitate comprehension in very young or language-impaired children. The narrative-discourse deficits of this subgroup appeared to be consistent with the hypothesis of a genetic liability for autism that expresses in milder forms and may include impaired language abilities.
Comparison of Responses to Air, Water, and Closed-Loop Caloric Irrigators
Authors: Karlsen Elizabeth A. , Mikhail Hany H. , Norris C. W. , Hassanein Ruth S.
Published: August 2014

Three types of commercially available caloric irrigation units—air, water, and closed-loop—were evaluated for nystagmus response patterns and comfort. Electronystagmographic recordings were analyzed for slow-phase velocity, response duration, amplitude, frequency, and test-retest reliability. Significant differences were found among the three types of irrigators, between warm and cool irrigators, and between male and female subjects. Test-retest reliability was adequate for all three units. Subjects clearly favored the closed-loop system over the water and air irrigators, but the water irrigator yielded the most robust caloric response.
Cross-Cultural Attitudes Toward Speech Disorders
Authors: Bebout Linda , Arthur Bradford
Published: August 2014

Speech‐language pathologists serving multicultural populations may encounter unfamiliar beliefs about speech disorders among the members of different cultures. This study used a questionnaire to look at attitudes toward four disorders (cleft palate, dysfluency, hearing impairment, and misarticulations) among 166 university students representing English-speaking North American culture and several other cultures (e.g., Chinese, Southeast Asian, Hispanic). The results showed significant group differences on items involving the subjects’ beliefs about the emotional health of persons with speech disorders and about the potential ability of speech-disordered persons to change their own speech.
The Identification of Affective-Prosodic Stimuli by Left- and Right-Hemisphere-Damaged Subjects
Authors: Lancker Diana Van , sidtis John J.
Published: August 2014

Impairments in listening tasks that require subjects to match affective-prosodic speech utterances with appropriate facial expressions have been reported after both left- and right-hemisphere damage. In the present study, both left- and right-hemisphere-damaged patients were found to perform poorly compared to a nondamaged control group on a typical affective-prosodic listening task using four emotional types (happy, sad, angry, surprised). To determine if the two brain-damaged groups were exhibiting a similar pattern of performance with respect to their use of acoustic cues, the 16 stimulus utterances were analyzed acoustically, and the results were incorporated into an analysis of the errors made by the patients. A discriminant function analysis using acoustic cues alone indicated that fundamental frequency (FO) variability, mean FO, and syllable durations most successfully distinguished the four emotional sentence types. A similar analysis that incorporated the misclassifications made by the patients revealed that the left-hemisphere-damaged and right-hemisphere-damaged groups were utilizing these acoustic cues differently. The results of this and other studies suggest that rather than being lateralized to a single cerebral hemisphere in a fashion analogous to language, prosodic processes are made up of multiple skills and functions distributed across cerebral systems.
Operant Response in Infants as a Function of Time Interval Following Signal Onset
Authors: Primus Michael A.
Published: August 2014

This study investigated the hypothesis that estimates of infant auditory threshold are lowered by extending the duration of individual test trials such that infants have more time to detect and respond to the acoustic signal. Forty 8- and 12-month-old infants were evaluated with an operant procedure to determine response latencies at four near-threshold levels. Resulting data were used to estimate the effect of trial duration on threshold by calculating the response performance that occurred at several intervals following signal onset. Findings indicate that most detection responses occurred in the initial 4 sec of the test trial, and use of an 8-sec trial interval yielded little gain in performance. The data reflect an insignificant shift (<5.0 dB) in threshold as a function of extended trial intervals.
Preferences for Verb Interpretation in Children With Specific Language Impairment
Authors: Kelly Donna J. , Rice Mabel L.
Published: August 2014

This study examined initial preferences for verb interpretation by children with specific language impairment (SLI), MLU-matched children, and age-matched children. Each child watched motion and change-of-state activity scenes on videotape and was then asked to point to the scene that depicted a novel verb, thereby indicating a preferred interpretation. The children were also asked to label the same activity scenes on a second tape. The findings indicated that the 5-year-old age-matched children exhibited a significant verb interpretation preference for the change-of-state scenes, whereas the children with specific language impairment and their 3-year-old MLU-matched peers did not have an interpretation preference for either the motion or change-of-state scenes. The children’s labeling of the activity scenes yielded findings that further supported group differences on the two semantic verb categories. The findings suggest that children’s initial verb interpretation biases vary relative to age and language proficiency.
Laryngeal Airway Resistance of Older Men and Women as a Function of Vocal Sound Pressure Level
Authors: Holmes Lori C. , Leeper Herbert A. , Nicholson Ian R.
Published: August 2014

This study examined laryngeal airway resistance (RLAW) in 10 healthy male and 10 female subjects within three age groups (55:0–64:11; 65:0–74:11; and 75:0+ years). A noninvasive procedure (Smitheran & Hixon, 1981) was employed to investigate RLAW at four vocal sound pressure levels (SPL) (25th, 50th, 75th percentiles of the SPL range, and comfortable voice level [CV]). RLAW values for the oldest group of females were found to be higher at each SPL percentile than those of the two younger age groups. The oldest group of males differed from the youngest group of males in RLAW values only at the 75th percentile level of SPL. Laryngeal airway resistance values were higher for females than males. As a group, the females generally had transglottal airflow that increased or remained relatively steady, whereas males maintained more linear changes in transglottal airflow and transglottal pressure as relative SPL increased. The present results suggest that separate norms need to be employed for males and females when determining RLAW values. Further, consideration should be given to examining the underlying airflow and pressure values when evaluating or monitoring changes in aerodynamic activity during voice production.
Respiratory and Laryngeal Measures of Children and Women With Bilateral Vocal Fold Nodules
Authors: Sapienza Christine M. , Stathopoulos Elaine T.
Published: August 2014

Simultaneous assessment of laryngeal and respiratory function was completed on 8 children and 10 women with bilateral vocal fold nodules and compared to that of 8 children and 10 women with normal voice production. Laryngeal function for the individuals with bilateral vocal fold nodules was characterized by significantly higher peak, altemating, and minimum glottal airflow. The presence of the high glottal airflow was accompanied by a significantly larger lung volume excursion. Both the children with nodules and those with normal voice showed laryngeal and respiratory function differences when compared to adults. All subject groups demonstrated appropriate laryngeal and respiratory function when increasing intensity from comfortable to loud speech. Simultaneous measurement of laryngeal and respiratory function using a multidimensional analysis of voice production is advocated in the evaluation of voice disorders because it can provide specific information regarding which of the subsystems of voice production are compromised.
Storytelling in Chippewa-Cree Children
Authors: Bird Elizabeth Kay-Raining , Vetter Delores Kluppel
Published: August 2014

The structure and content of self-generated narratives were compared for 20 traditional and 20 nontraditional Chippewa-Cree children in four age groups (5, 7, 9, and 11 years). A majority of the stories contained temporally and causally related events and goal-based action. MLT-unit of the narratives was longer and highly structured stories were constructed more frequently with increasing age. The two traditionality groups differed developmentally in their use of obstacles and causally connected episodes. The stories of 11-year-old traditional children were significantly more likely to contain these elements than their 5-year-old counterparts, whereas similar comparisons for nontraditional children revealed no such developmental change. In terms of story content, intrapersonal obstacles were found to be employed by the oldest groups only and were used more frequently by these Chippewa-Cree children than had been previously reported (e.g., Stein, 1988). Several later-developing aspects of story content were identified that seemed to reflect a Cree cultural influence. These results provide evidence for the use of episodic structure by Chippewa-Cree children, but suggest that the developmental course for particular story structure and content can vary as a function of culture.
Effect of Familiarity on Word Duration in Children’s Speech: A Preliminary Investigation
Authors: Schwartz Richard G.
Published: August 2014

Young children’s productions of novel words were used to investigate the influence of word familiarity on vowel and word duration. Ten children, 18 to 21 months old, produced tokens of phonologically individualized words (from one to four words) over 12 experimental sessions. Comparisons of means for the individualized words revealed that productions in the second half of the sessions were significantly shorter (both in their vowel and overall duration) than those in the first six sessions. When mean durations of productions were derived for each child, the effect held for word durations. Vowel durations differed in the same direction, but the difference was not statistically significant. Under these controlled conditions, familiarity seemed to influence the duration of early productions of novel words. These findings are discussed as evidence of word-specific motor maturation in early lexical acquisition.
Derivation of Frequency-Gain Characteristics for Maximizing Speech Reception in Noise
Authors: Rankovic Christine M.
Published: August 2014

Hearing aid gain-assignment schemes known as "prescriptions" were
not
designed for fitting hearing aids that modify their frequency responses to reduce background noise interference. Rather, prescriptions were developed for hearing aids having single, fixed frequency responses and aim to optimize speech reception in relatively quiet environments. Even though prescriptions do not apply to noisy conditions specifically, they embody the trade between maximizing speech audibility and maintaining loudness comfort that is critical to frequency-gain characteristic selection independent of whether noise is present or absent. The articulation index (Al) was used to examine the extent to which prescriptions' deference to loudness comfort causes them to fall short of maximizing speech spectrum audibility, thereby revealing (roughly) the magnitude of the loudness control built into prescriptions. Als for speech amplified by an Al-maximizing rule (MAX Al) (Rankovic, Freyman, & Zurek, 1992) and according to several prescriptions were calculated as a function of hearing loss degree and configuration for quiet and noisy conditions. In quiet, Als for prescriptions were similar to one another when presented with the same audiogram but were drastically smaller than MAX Als, implying that prescriptions limit speech audibility to a large extent to prevent loudness discomfort. In noise, maximizing the Al required frequency-gain characteristics that were substantially different from prescription-assigned characteristics and that were unique to each noise/audiogram combination. A loudness constraint for the MAX Al scheme was developed to account for the gain discrepancy between prescription Als and MAX Als observed in the quiet condition, based on the highest comfortable loudness (HCL) equations presented by Cox (1989) in combination with a loudness model (von Paulus & Zwicker, 1972). The MAX Al scheme with the new loudness control was extended to specify frequency-gain characteristics expected to be optimal for several conditions containing noise, and examples are presented.
Time-Interval Measurement of Stuttering: Establishing and Modifying Judgment Accuracy
Authors: Cordes Anne K. , Ingham Roger J.
Published: August 2014

The purpose of this study was to determine whether accuracy training for interval judgments of stuttering might generalize to increased accuracy and/or interjudge agreement for intervals other than those used during training. Ten upper-division speech-language pathology students judged 5-s audiovisually recorded speech intervals as stuttered or nonstuttered in a series of group and single-subject experiments. Judgment accuracy was determined with respect to judgments provided previously by 10 recognized authorities on stuttering and its treatment. Training occurred within single-subject experiments that used multiple baselines across speakers and repeated generalization probes to assess training effects. Results showed that judgment accuracy tended to increase after training for speakers used during the training process as well as for unfamiliar speakers. Results also replicated previous findings of slight increases in interjudge and intrajudge agreement after interval-judgment training. The implications of these results for developing a valid and reliable stuttering measurement system are discussed.
Preference for and Performance With Damped and Undamped Hearing Aids by Listeners With Sensorineural Hearing Loss
Authors: Davis Lynne A. , Davidson Stephanie A.
Published: August 2014

This study investigated the relationship between acoustic damping of hearing aid responses and listeners’ speech discrimination and judgments of preference and sound quality. Eighteen subjects with essentially equivalent hearing impairments participated. Subjects’ speech discrimination was evaluated for a male talker in quiet and in noise and for a female talker in the same conditions with hearing aids with 0 dB, −5 dB, and −10 dB of damping. Subjects also compared the damping levels using eight bipolar adjective pairs and provided judgments of overall preference. Measurements of the hearing aid responses were made in a 2-cm
3
coupler and in the subjects’ ears using probe microphone techniques. Smoothness of the responses was quantified using the Index of Response Irregularity (IRI) and the Frequency Response Smoothness Quantification Index (FReSQI). Subjects preferred the two damped hearing aid responses to the undamped. They also had better speech discrimination with damped hearing aid responses. The bipolar adjectives were of limited use in comparing hearing aids. A few questions about hearing aid sound quality and preference appear adequate for evaluating listeners’ choice of hearing aids. Smoothness of the hearing aid responses in the test box was higher for the damped hearing aids than for the undamped. However, for real ear responses measured using a probe microphone, smoothness did not change as a function of damping level.
Effects of Age and Alzheimer's Disease on Recognition of Gated Spoken Words
Authors: Marshall Nancy B. , Duke Linda W. , Walley Amanda C.
Published: August 2014

This study investigated the effects of normal aging and Alzheimer's disease on listeners' ability to recognize gated spoken words. Groups of healthy young adults, healthy older adults, and adults with Alzheimer's disease were presented isolated gated spoken words. Theoretical predictions of the Cohort model of spoken word recognition (Marslen-Wilson, 1984) were tested, employing both between-group and within-group comparisons. The findings for the young adults supported the Cohort model's predictions. The findings for the older adult groups revealed different effects for age and disease. These results are interpreted in relation to the theoretical predictions, the findings of previous gating studies, and differentiating age from disease-related changes in spoken word recognition.
Selected Cognitive Factors and Speech Recognition Performance Among Young and Elderly Listeners
Authors: Gordon-Salant Sandra , Fitzgibbons Peter J.
Published: August 2014

The influence of selected cognitive factors on age-related changes in speech recognition was examined by measuring the effects of recall task, speech rate, and availability of contextual cues on recognition performance by young and elderly listeners. Stimuli were low and high context sentences from the R-SPIN test presented at normal and slowed speech rates in noise. Response modes were final word recall and sentence recall. The effects of hearing loss and age were examined by comparing performances of young and elderly listeners with normal hearing and young and elderly listeners with hearing loss. Listeners with hearing loss performed more poorly than listeners with normal hearing in nearly every condition. In addition, elderly listeners exhibited poorer performance than younger listeners on the sentence recall task, but not on the word recall task, indicating that added memory demands have a detrimental effect on elderly listeners' performance. Slowing of speech rate did not have a differential effect on performance of young and elderly listeners. All listeners performed well when stimulus contextual cues were available. Taken together, these results support the notion that the performance of elderly listeners with hearing loss is influenced by a combination of auditory processing factors, memory demands, and speech contextual information.
Effect of Fingerspelling Task on Temporal Characteristics and Perceived Naturalness of Speech in Simultaneous Communication
Authors: Schiavetti Nicholas , Whitehead Robert L. , Whitehead Brenda , Metz Dale Evan
Published: August 2014

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.
Evaluation of the Vocal Performance of Children Using a Voice Range Profile Index
Authors: Heylen Louis , Wuyts Floris L. , Mertens Fons , Bodt Marc De , Pattyn Jos , Croux Christophe , Heyning Paul H. Van de
Published: August 2014

Voice range profiles (VRPs) were analyzed according to 11 frequency, intensity, and morphological characteristics for 94 normal children and 136 children with vocal fold pathologies (ages 6–11 years). Normative data are presented showing marked differences between the groups. Using a specific combination of the child's age, the highest vocal fundamental frequency, the lowest intensity, and the slope of the upper VRP contour, a Voice Range Profile Index for Children (VRPIc) may be constructed using discriminant analysis. It is shown how the VRPIc can be used to screen children for vocal disorder or to quantitatively assess the effectiveness of voice treatment. Since the group means of the VRPIc for healthy and dysphonic children are scaled to +10 and –10, respectively, the VRPIc enables the clinician to rate a child's vocal performance with reference to healthy and dysphonic children in general. The sensitivity and specificity of this method was found to be 90% and 83%, respectively.
Phonological Words and Stuttering on Function Words
Authors: Au-Yeung James , Howell Peter , Pilgrim Lesley
Published: August 2014

Stuttering on function words was examined in 51 people who stutter. The people who stutter were subdivided into young (2 to 6 years), middle (6 to 9 years), and older (9 to 12 years) child groups; teenagers (13 to 18 years); and adults (20 to 40 years). As reported by previous researchers, children up to about age 9 stuttered more on function words (pronouns, articles, prepositions, conjunctions, auxiliary verbs), whereas older people tended to stutter more on content words (nouns, main verbs, adverbs, adjectives). Function words in early positions in utterances, again as reported elsewhere, were more likely to be stuttered than function words at later positions in an utterance. This was most apparent for the younger groups of speakers. For the remaining analyses, utterances were segmented into phonological words on the basis of Selkirk’s work (1984). Stuttering rate was higher when function words occurred in early phonological word positions than other phonological word positions whether the phonological word appeared in initial position in an utterance or not. Stuttering rate was highly dependent on whether the function word occurred before or after the single content word allowed in Selkirk’s (1984) phonological words. This applied, once again, whether the phonological word was utterance-initial or not. It is argued that stuttering of function words before their content word in phonological words in young speakers is used as a delaying tactic when the forthcoming content word is not prepared for articulation.
Nonword Repetition and Child Language Impairment
Authors: Dollaghan Chris , Campbell Thomas F.
Published: August 2014

A brief, processing-dependent, nonword repetition task, designed to minimize biases associated with traditional language tests, was investigated. In Study 1, no overlap in nonword repetition performance was found between a group of 20 school-age children enrolled in language intervention (LI) and a group of 20 age-matched peers developing language normally (LN). In Study 2, a comparison of likelihood ratios for the nonword repetition task and for a traditional language test revealed that nonword repetition distinguished between children independently identified as LI and LN with a high degree of accuracy, by contrast with the traditional language test. Nonword repetition may have considerable clinical utility as a screening measure for language impairment in children. Information on the likelihood ratios associated with all diagnostic tests of language is badly needed.
The Effects of Decreased Audibility Produced by High-Pass Noise Masking on N1 and the Mismatch Negativity to Speech Sounds /ba/ and /da/
Authors: Martin Brett A. , Kurtzberg Diane , Stapells David R.
Published: August 2014

This study investigated the effects of decreased audibility produced by high-pass noise masking on the cortical event-related potentials (ERPs) N1 and mismatch negativity (MMN) to the speech sounds /ba/ and /da/, presented at 65 dB SPL. ERPs were recorded while normal listeners (
N
=11) ignored the stimuli and read a book. Broadband masking noise was simultaneously presented at an intensity sufficient to mask the response to the speech sounds, and subsequently high-pass filtered. The conditions were QUIET (no noise); high-pass cutoff frequencies of 4000, 2000, 1000, 500, and 250 Hz; and broadband noise. Behavioral measures of discrimination of the speech sounds (
d
' and reaction time) were obtained separately from the ERPs for each listener and condition. As the cutoff frequency of the high-pass masker was lowered, ERP latencies increased and amplitudes decreased. The cutoff frequency where changes first occurred differed for N1 and MMN. N1 showed small systematic changes across frequency beginning with the 4000-Hz high-pass noise. MMN and behavioral measures showed large changes that occurred at approximately 1000 Hz. These results indicate that decreased audibility, resulting from the masking, affects N1 and the MMN in a differential manner. N1 reflects the presence of audible stimulus energy, being present in all conditions where stimuli were audible, whether or not they were discriminable. The MMN is present only for those conditions where stimuli were behaviorally discriminable. These studies of cortical ERPs in high/pass noise studies provide insight into the changes in brain processes and behavioral performance that occur when audibility is reduced, as in hearing loss.
An Acoustic Analysis of the Development of CV Coarticulation
Authors: Sussman Harvey M. , Duder Celeste , Dalston Eileen , Cacciatore Antonina
Published: August 2014

This study analyzed stop consonant-vowel productions from babbling to meaningful speech in a single female child spanning the period from age 7 months to age 40 months. A total of 7,888 utterances (3,103 [bV], 3,236 [dV], and 1,549 [gV]) were analyzed to obtain frequencies at F2 onset and F2 at vocalic center for each utterance. A linear regression line (“locus equation”) was fit to the cluster of F2 coordinates per stop place category produced during each month. The slope of the regression lines provided a numerical index of vowel-induced coarticulation on consonant productions. Labial, alveolar, and velar CV productions followed distinct articulatory paths toward adult-like norms of coarticulation. Inferences about the gradual emergence of segmental independence of the consonant and vowel in the three stop place environments were made from locus equation scatterplots and mean F2 onset and F2 midvowel frequencies obtained across babbling, early words, and natural speech.
Guiding Language Development
Authors: Hammer Carol Scheffner , Weiss Amy L.
Published: August 2014

This investigation explored how African American mothers and their infants at the single-word stage of development structured their play and communicated with one another. Six mother-child dyads of low socioeconomic status (SES) and six of middle SES were observed at play. Few group differences were found, with the majority of the differences involving language behaviors. The middle-SES dyads included language goals more often in their play. Middle-SES infants initiated play verbally more frequently and produced over twice as many vocalizations as their low-SES peers. In addition, middle-SES mothers used a wider variety of words when playing with their children than their low-SES counterparts. A range of play styles was found within both groups. These were categorized into three general play styles: mothers and children actively involved in play; mothers' involvement varied; and children actively engaged and mothers attentive.
Acoustic and Airflow Spectral Analysis of Voice Tremor
Authors: Jiang Jack , Lin Emily , Hanson David G.
Published: August 2014

Acoustic spectral analysis has been used to describe voice tremor with some success, but no feature distinguishing pathological from normal tremor has been clearly identified. To assist in monitoring voice tremor associated with neurological diseases, objective and quantifiable measures that can distinguish between normal and pathological tremor are desired. This study explored the plausibility of using airflow and acoustic signals to quantify the frequency and amplitude of voice tremor and potentially to distinguish pathological from normal tremor. Subjects were 10 individuals with pathological tremor, most of them individuals with Parkinson's disease, and 10 gender and age-matched individuals with no voice disorder. Simultaneous acoustic and airflow signals were recorded during sustained vowel phonation. The acoustic intensity contours and the airflow signals were submitted to spectral analysis. A peak prominence ratio, defined as the ratio of the spectral peak energy to the overall signal energy, was calculated for each spectral peak below 30 Hz. For each subject, the 6 spectral peaks with the highest peak prominence ratios were selected. Frequency values of the 6 selected acoustic or airflow spectral peaks failed to distinguish tremor group from control group. Peak prominence ratios of the 6 selected acoustic spectral peaks were significantly higher for tremor group than for control group. Although spectral analysis of airflow signals was not useful in differentiating tremor group from control group, acoustic intensity contours and airflow time waveforms were highly and positively correlated in more tremor subjects (90%) than control subjects (40%). This finding suggests that the relationship between acoustic intensity contours and airflow time waveforms may reflect the presence and the source of voice tremor.
Effects of Otitis Media With Effusion on Hearing in the First 3 Years of Life
Authors: Gravel Judith S. , Wallace Ina F.
Published: August 2014

Hearing sensitivity was examined prospectively in young children as a function of otitis media with effusion (OME) status in Years 1, 2, and 3. Hearing and OME status were sampled bimonthly from 5 to 36 months of age. Behavioral thresholds were obtained at 4 test frequencies (500, 1000, 2000, and 4000 Hz) using visual reinforcement audiometry and conditioned play audiometry techniques. The majority of children's audiograms were obtained using a computer-controlled test procedure. Thresholds for the test frequencies were averaged for each visit and then averaged across all visits in each year. Reference values were developed for infants and children in Years 1, 2, and 3 who were OME free. Results reveal that children who were classified as bilaterally OME positive in Years 1, 2, and 3 had significantly poorer hearing than children classified as bilaterally OME free in each of these time periods. There was no difference in hearing as a function of gender, socioeconomic status, or birth-risk status.
Acoustic Differences Between Content and Function Words in Amyotrophic Lateral Sclerosis
Authors: Turner Greg S. , Tjaden Kris
Published: August 2014

Studies describing acoustic characteristics of speech produced by individuals with dysarthria may help to explain intelligibility deficits for these speakers. One goal of the current study was to investigate the manner and extent to which nine speakers with mild to moderate dysarthria associated with amyotrophic lateral sclerosis (ALS) and nine healthy speakers acoustically distinguished /i/, / æ/, /u/, and /α/ in content and function words. A further aim was to evaluate the relationship between impaired speech in ALS and the magnitude of acoustic differences for vowels in content and function words. Speakers read the Farm Passage at a comfortable or habitual rate. F1 and F2 midpoint frequencies were measured, and vowel space areas were calculated. Vowel durations also were measured. The magnitude of F1, F2, vowel space area, and duration differences for vowels in content and function words was not statistically different for speakers with ALS and healthy controls. In addition, with the exception of /i/ produced by some speakers with ALS, vowel duration tended to be shorter in function words. Average F1 and F2 values for function words also tended to be centralized relative to content words. Although vowel space area differences for the two speaker groups were not statistically significant, there was a tendency for the difference in vowel space area for content and function words to be smaller for speakers with ALS than for controls. Regression analyses further indicated that the magnitude of temporal differences for vowels in content and function words was a better predictor of impaired speech than the magnitude of spectral differences for vowels in content and function words. One clinical implication is that individuals with ALS may benefit from therapy techniques targeting temporal properties of the acoustic signal.
Modulations in Respiratory and Laryngeal Activity Associated With Changes in Vocal Intensity During Speech
Authors: Finnegan Eileen M. , Luschei Erich S. , Hoffman Henry T.
Published: August 2014

We tested the hypothesis that different strategies are used to alter tracheal pressure (P
t
) during sustained and transient increases in intensity. It has been suggested that the respiratory system plays the primary role in P
t
changes associated with alteration in overall intensity, whereas laryngeal adjustment is primary for transient change in P
t
related to emphasis. Tracheal pressure, obtained via tracheal puncture, airflow (U), and laryngeal electromyography from the thyroarytenoid muscle (TA EMG) were collected from 6 subjects during sentence production at different intensity levels and with various stress patterns. Using a technique described in a previous study, we computed lower airway resistance (R
law
) from measures of P
t
and U obtained during a sudden change in upper airway resistance. We used this resistance value, together with direct measures of P
t
and U during speech, to derive a time-varying measure of alveolar pressure (P
a
), the pressure created by respiratory muscle activity and elastic recoil of the lungs. P
a
provided a measure of respiratory drive that was unaffected by laryngeal activity. Laryngeal airway resistance (R
lx
) and TA EMG provided measures of laryngeal activity. The results of this study indicated that, contrary to the outcome predicted by the hypothesis, there was no difference in the strategies used to alter P
t
during sustained and transient increases in intensity. Although changes in both P
a
and R
lx
contributed to increase in P
t
, the contribution of P
a
was substantially greater. On average, P
a
contributed to 94% and R
lx
to 6% of the increase in P
t
associated with vocal intensity. A secondary purpose of the study was to determine the extent to which laryngeal muscle activity was related to R
lx
during speech. We found TA EMG activity increased with intensity but was not well correlated with R
lx
, suggesting that when it contracts, the TA muscle may affect intensity by loosening the cover, which allows for greater amplitude of vocal fold vibration, without necessarily increasing laryngeal airway resistance.
Influence of Continuous Speaking on Ventilation
Authors: Hoit Jeannette D. , Lohmeier Heather L.
Published: August 2014

This study was conducted to explore the influence of speaking on ventilation. Twenty healthy young men were studied during periods of quiet breathing and prolonged speaking using noninvasive methods to measure chest wall surface motions and expired gas composition. Results indicated that all subjects ventilated more during speaking than during quiet breathing, usually by augmenting both tidal volume and breathing frequency. Ventilation did not change across repeated speaking trials. Quiet breathing was altered from its usual behavior following speaking, often for several minutes. Speaking-related increases in ventilation were found to be strongly correlated with lung volume expenditures per syllable. These findings have clinical implications for the respiratory care practitioner and the speech-language pathologist.
SIG 1 Perspectives Vol. 19, No. 2, March 2012
Authors: Mazefsky Carla A.
Published: August 2014

Sorry, this activity is no longer available for CEUs. Visit the SIG 1 page on the
ASHA Store
to see available CE activities.

Use the CE questions PDF here as study questions to guide your Perspectives reading.
SIG 3 Perspectives Vol. 22, No. 1, March 2012
Authors: Hapner Edie R.
Published: August 2014

Sorry, this activity is no longer available for CEUs. Visit the SIG 3 page on the
ASHA Store
to see available CE activities.

Use the CE questions PDF here as study questions to guide your Perspectives reading.
Using Popular Mobile Devices in Voice Therapy
Authors: van Leer Eva
Published: August 2014

Mobile tools are increasingly available to help individuals monitor their progress toward health behavior goals. Commonly known commercial products for health and fitness self-monitoring include wearable devices such as the Fitbit© and Nike + Pedometer© that work independently or in conjunction with mobile platforms (e.g., smartphones, media players) as well as web-based interfaces. These tools track and graph exercise behavior, provide motivational messages, offer health-related information, and allow users to share their accomplishments via social media. Approximately 2 million software programs or “apps” have been designed for mobile platforms (Pure Oxygen Mobile, 2013), many of which are health-related. The development of mobile health devices and applications is advancing so quickly that the Food and Drug Administration issued a Guidance statement with the purpose of defining mobile medical applications and describing a tailored approach to their regulation.
Two‐level scheme to maximise the number of guaranteed users in downlink femtocell networks
Authors: Wang Kan , Li Hongyan , Ma Jianpeng , Liu Peng , Pan Hao
Published: August 2014

In this study, the authors study the downlink resource allocation optimisation in femtocell networks, to maximise the number of guaranteed users whose data rate requirements are fully met. The spectral access of femtocell networks is based on orthogonal frequency division multiple access. In their work, two challenges are solved. The first is the intractable inter‐cell interference coordination brought about by the transmission delay in backhaul connections, and the second is the incorporation of physical interference model into problem formulations. To solve these problems, the authors propose a novel two‐level resource allocation scheme, implemented in both radio resource management controller and femtocell base stations, based on the maximisation of the number of guaranteed users. Notably, their proposed scheme is efficient and requires low overhead. Simulation results show that the proposed scheme offers significant performance improvement in both the percentage of guaranteed users and spectrum spatial reuse over existing methods proposed in the literature.
Improved maximum a posteriori signal detection for amplify‐and‐forward relay networks with imperfect channel state information
Authors: Zhang Yi , Khalighi Mohammad Ali , Sadough Seyed Mohammad‐Sajad , Bourennane Salah
Published: August 2014

In amplify‐and‐forward wireless relay networks, channel state information is required at the destination for signal detection when coherent distributed space‐time coding is performed at the relays. The authors consider in this study signal detection in the case of imperfect partial channel knowledge at the destination. For the case of maximum a posteriori signal detection, they propose a modified detector formulation that takes the variance of channel estimation errors into account, and reduces the impact of channel uncertainty on the receiver performance. They show that the proposed modification permits a significant performance improvement, while increasing only slightly the receiver's complexity. It is of special interest for non‐constant modulus signal constellations of relatively large size, as well as for relatively low pilot powers.