Relationship between the Discrimination of /w-r/ and /t-d/ Continua and the Identification of Distorted /r/

1988 ◽  
Vol 31 (2) ◽  
pp. 193-206 ◽  
Author(s):  
Donald J. Sharf ◽  
Ralph N. Ohde ◽  
Mark E. Lehman
Keyword(s):  
Category Boundary ◽  
Vowel Duration ◽  
Individual Subject ◽  
Group Response ◽  
Before And After ◽  
Response Choices ◽  
Subject Performance

The purpose of this study was to assess the extent to which listeners can perceive intraphonemic differences. In Experiment 1, subjects identified synthesized acoustic tokens of child-like speech that varied in second and third formant (F 2 and F 3 ) onset frequencies as /w/, /r/, or distorted /r/ in two conditions: (a) with and without feedback of the group response choices, and (b) before and after training to identify the best examples of /w/, /r/, and distorted /r/ based on their identification in the first condition. The results were: (a) some subjects consistently identified distorted /r/ above criterion, and (b) feedback was more effective in increasing distorted /r/ identification than was training. In Experiment 2, the same subjects participated in discrimination tasks using stimuli from a synthesized child /w-r/ continuum that varied in F 2 and F 3 onsets and from a synthesized adult /t-d/ continuum that varied in preconsonantal vowel duration. The results were: (a perception was not categorical for both continua, (b) little relation was found between distorted-/r/ identification and measures of /w-r/ discrimination, and (c) a high and significant correlation was found between identification of distorted /r/ and within-/d/ discrimination. In Experiment 3, different subjects identified the child manifold stimuli and discriminated stimuli in a synthesized child /w-r/ continuum and in a synthesized adult /t-d/ continuum. The results were: (a) neither /w-r/ or /t-d/ perception was categorical although the former came closer than the latter in terms of individual subject performance, (b) there was a high and significant correlation between distorted-/r/ identification and within-/r/ discrimination of /w-r/ stimuli, and (c) there were high and significant correlations between distorted-/r/identification and mean, cross-category boundary, and within-/t/discrimination of /t-d/ stimuli.

Temporal Characteristics of Speech in Simultaneous Communication

1995 ◽  
Vol 38 (5) ◽  
pp. 1014-1024 ◽  
Author(s):  
Robert L. Whitehead ◽  
Nicholas Schiavetti ◽  
Brenda H. Whitehead ◽  
Dale Evan Metz
Keyword(s):  
Pause Duration ◽  
Vowel Duration ◽  
Vowel Perception ◽  
Temporal Characteristics ◽  
Spoken English ◽  
Temporal Features ◽  
Before And After ◽  
Word Duration ◽  
Rate Of Speech ◽  
Speech Condition

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

Relationship between Rate of Preparation for, and Processing of, an Event Requiring a Choice Response

1989 ◽  
Vol 41 (1) ◽  
pp. 47-62 ◽  
Author(s):  
E. A. Maylor ◽  
P. M. A. Rabbitt
Keyword(s):  
Individual Differences ◽  
Response Time ◽  
Choice Response ◽  
Response Stimulus ◽  
Group Response ◽  
Before And After ◽  
Practice Trials ◽  
Experimental Trials ◽  
The Relationship ◽  
Speed And Accuracy

It is known that alcohol increases the time taken to identify signals and to make responses to them, but it is not known whether it also slows the rate of preparation for such events. These two performance parameters are not necessarily related, as age affects the former but not the latter. Twenty subjects participated in a 4-choice reaction time experiment in which they received no alcohol (NA) in the first session and either no alcohol (10 subjects) or 0.8 ml alcohol (A) per kg body weight (10 subjects) in the second session. In each session there were 300 practice trials, followed by 400 experimental trials at each one of five Response–Stimulus Intervals (RSI: 50, 100, 200, 400, and 800 msec). There was a significant effect of alcohol such that the reduction in response time from the first to the second session was 39 msec larger for the NA/NA group than for the NA/A group. Response time decreased significantly with increasing RSI, but there was no interaction between the effect of alcohol and RSI. Thus, alcohol slows the processing of an event requiring a choice response; however, like age and individual differences, but unlike practice, alcohol has no effect on the rate of preparation for that event. In addition, an analysis of what happened before and after an error revealed that practice and increasing RSI produce real improvements in performance rather than shifts in the tradeoff between speed and accuracy, whereas alcohol produces a real impairment. It is concluded that the relationship between the rate of preparation for, and processing of, a stimulus is not simple, as one factor (practice) influences both rates, whereas other factors (alcohol, individual differences, and age) influence the rate of processing only.

Training Effects on Vowel Production by Two Profoundly Hearing-Impaired Speakers

1987 ◽  
Vol 30 (2) ◽  
pp. 241-251 ◽  
Author(s):  
Mary Joe Osberger
Keyword(s):  
Normal Hearing ◽  
Hearing Impaired ◽  
The Other ◽  
Control Group ◽  
Vowel Duration ◽  
Vowel Production ◽  
Training Effects ◽  
Acoustic Measures ◽  
Before And After ◽  
Speech Training

Two profoundly hearing-impaired adolescents received systematic speech training to improve their production of the vowels /i/ and /æ/. Acoustic measures of F 1 , F 2 , and duration, and listener judgments of vowel acceptability, were used to quantify vowel production before and after training. Both subjects demonstrated significant changes in their production of the two vowels at the acoustic and perceptual levels following treatment. The changes were highly individualized. For some features, significant improvement occurred posttreatment with differences between the hearing-impaired subject and a control group of subjects with normal hearing no longer present. There was a significant improvement in the acceptability of the two vowels in each subject's speech after training. Vowel duration remained unchanged in the speech of one subject whereas it increased in the speech of the other subject following training. There was a trend toward reduced token-to-token variation in the posttreatment samples. Acoustic and perceptual measures also were obtained on two vowels not directly trained in the program. Significant changes occurred in the production of these segments but some of the changes resulted in greater deviation in the post- than in the pretreatment samples.

Perception/Production Relationships in the Development of the Vowel Duration Cue to Final Consonant Voicing

1989 ◽  
Vol 32 (4) ◽  
pp. 803-815 ◽  
Author(s):  
Mark E. Lehman ◽  
Donald J. Sharf
Keyword(s):  
Age Groups ◽  
Category Boundary ◽  
Pairwise Comparisons ◽  
Vowel Duration ◽  
Synthesized Speech ◽  
Boundary Width ◽  
Response Consistency ◽  
Correct Discrimination ◽  
Percentage Correct ◽  
Consonant Voicing

The purposes of this study were to assess: (a) the development of identification and discrimination in children for the vowel duration cue to final consonant voicing and (b) the perception/production relationships in children for the vowel duration cue to final consonant voicing. Subjects were 30 children divided equally into three age groups, and 10 adults. Productions consisted of 15 repetitions of two target syllables (beet, bead) analyzed acoustically for vowel duration. From these were calculated category boundary, category separation, and variability in production for each subject. Perceptual data were collected using a synthesized speech continuum that varied vowel duration. Identification responses were used to calculate category boundary, category separation (slope/boundary width) and variability (response consistency) for each subject. Mean percentage correct discrimination was derived by using two-step and three-step two-pair same-different paradigms. The results were as follows: (a) category boundary and category separation in production were adult-like by 8 years of age, (b) variability in production was not adult-like by 10 years of age, (c) perception categorization (category boundary and category separation) was adult-like at 5 years of age, (d) perceptual consistency was not adult-like until 10 years of age, (e) percentage correct discrimination was not adult-like by 10 years of age, (f) correlations between comparable perception and production measures were nonsignificant, and (g) a pairwise comparisons analysis indicated that perception was consistently more advanced than production.

scholarly journals Non-parametric Functional Muscle Network as a Robust Biomarker of Fatigue

2021 ◽  
Author(s):  
Rory O'Keeffe ◽  
Seyed Yahya Shirazi ◽  
Jinghui Yang ◽  
Sarmad Mehrdad ◽  
Smita Rao ◽  
...  
Keyword(s):  
Unmet Need ◽  
Clustering Coefficient ◽  
P Value ◽  
Median Frequency ◽  
Individual Subject ◽  
Before And After ◽  
Network Metrics ◽  
Fatigue Detection ◽  
First Time ◽  
Non Parametric

The possibility of muscle fatigue detection using surface electromyography has been explored and multiple biomarkers, such as median frequency, have been suggested. However, there are contradictory reports in the literature which result in an inconsistent understanding of the biomarkers of fatigue. Thus, there is an unmet need for a statistically robust sEMG-based biomarker for fatigue detection. This paper, for the first time, demonstrates the superior capability of a non-parametric muscle network to reliably detect fatigue-related changes. Seven healthy volunteers completed a lower limb exercise protocol, which consisted of the 30s of a sit-to-stand exercise before and after the completion of fatiguing leg press sets. A non-parametric muscle network was constructed, using Spearman's power correlation, and showed a very reliable decrease in network metrics associated with fatigue (degree, weighted clustering coefficient (WCC)). The network metrics displayed a significant decrease at the group level (degree, WCC: p-value<0.001), individual subject level (degree: p-value<0.035 WCC: p-value<0.004) and particular muscle level (degree: p-value<0.017). Regarding the decrease in mean degree connectivity at particular muscles, all seven subjects followed the group trend. In contrast to the robust results achieved by the proposed non-parametric muscle network, classical spectrotemporal measurements showed heterogeneous trends at the particular muscle and individual subject levels. Thus, this paper for the first time shows that a non-parametric muscle network is a reliable biomarker of fatigue and could be used in a broad range of applications.

scholarly journals Testing for Transition

2019 ◽  
Vol 38 (4) ◽  
pp. 76-97
Author(s):  
Ashley Lierman ◽  
Bethany Scott ◽  
Mea Warren ◽  
Cherie Turner
Keyword(s):  
Online Survey ◽  
User Needs ◽  
Individual Subject ◽  
Card Sort ◽  
Face To Face ◽  
Before And After ◽  
Library Resources ◽  
Testing Protocols ◽  
Insight Into ◽  
Large Research

This article describes multiple stages of usability testing that were conducted before and after a large research library’s transition to a new platform for its research guides. A large interdepartmental team sought user feedback on the design, content, and organization of the guide homepage, as well as on individual subject guides. This information was collected using an open-card-sort study, two face-to-face, think-aloud testing protocols, and an online survey. Significant findings include that users need clear directions and titles that incorporate familiar terminology, do not readily understand the purpose of guides, and are easily overwhelmed by excess information, and that many of librarians’ assumptions about the use of library resources may be mistaken. This study will be of value to other library workers seeking insight into user needs and behaviors around online resources.

Phonatory and Articulatory Changes Associated With Increased Vocal Intensity in Parkinson Disease: A Case Study

1995 ◽  
Vol 38 (4) ◽  
pp. 751-764 ◽  
Author(s):  
Christopher Dromey ◽  
Lorraine Olson Ramig ◽  
Antonia B. Johnson
Keyword(s):  
Parkinson Disease ◽  
Maximum Flow ◽  
Intensity Change ◽  
Vowel Duration ◽  
Acoustic Measures ◽  
Syllable Repetition ◽  
Before And After ◽  
Subglottal Pressure ◽  
Vocal Intensity ◽  
Whole Word

This study examined changes in voice and speech production in a patient with Parkinson disease as he increased vocal intensity following 1 month of intensive voice treatment. Phonatory function and articulatory acoustic measures were made before and after treatment as well as 6 and 12 months later. Pre- to post-treatment increases were documented in sound pressure level in sustained phonation, syllable repetition, reading, and monologue. Consistent with mechanisms of intensity change reported in normal speakers, corresponding improvements were measured in estimated subglottal pressure, maximum flow declination rate, laryngeal airway resistance, open quotient, EGGW-25, harmonic-spectral slope, and maximum vowel duration. Measures of phonatory stability in sustained phonation and semitone standard deviation in reading and speaking showed changes accompanying increased vocal intensity. In addition, changes were measured in articulatory acoustic parameters (vowel and whole word duration, transition duration, extent and rate, and frication duration and rise time) in single-word productions. These findings indicate that this patient increased his vocal intensity using phonatory mechanisms that have been associated with the nondisordered larynx. In addition, the increased vocal intensity led to changes in articulation that were not targeted in treatment.

Serum Complement Changes During Double-Blind Food Challenges in Children with a History of Food Sensitivity

PEDIATRICS ◽  
1984 ◽  
Vol 73 (4) ◽  
pp. 532-537
Author(s):  
Michael E. Martin ◽  
Lindsay A. Guthrie ◽  
S. Allan Bock
Keyword(s):  
Alternative Pathway ◽  
Food Challenge ◽  
Serum Levels ◽  
Serum Complement ◽  
Double Blind ◽  
Individual Subject ◽  
Food Sensitivity ◽  
Before And After ◽  
The Difference ◽  
Food Challenges

Serum levels of C3, C4, factor B, properdin, total hemolytic complement and alternative-pathway hemolytic activity were measured before and after double-blind food challenge in 23 children with impressive histories of adverse reactions to foods. The 23 subjects had 11 positive food challenges and 12 negative food challenges. Nine patients with reagin-mediated positive food challenges showed increases in all six complement assays after double-blind food challenge, while the group with negative food challenges showed decreases in five of the six assays. The difference between the two groups for complement changes after double-blind food challenge was significant only for the alternative-pathway assay. Individual subject analysis revealed markedly heterogeneous changes in direction and magnitude within both groups for all complement assays. Therefore, it is concluded that measurement of serum complement levels is not a useful test for the clinical evaluation of a patient with suspected food sensitivity.

Deformation Replication

1970 ◽  
Vol 28 ◽  
pp. 280-281
Author(s):  
J. Temple Black
Keyword(s):  
Cutting Speed ◽  
Machining Process ◽  
Depth Of Cut ◽  
Rake Face ◽  
Orthogonal Machining ◽  
Aluminum Chips ◽  
Before And After ◽  
Materials Used ◽  
Glass Knife ◽  
Very High

Tool materials used in ultramicrotomy are glass, developed by Latta and Hartmann (1) and diamond, introduced by Fernandez-Moran (2). While diamonds produce more good sections per knife edge than glass, they are expensive; require careful mounting and handling; and are time consuming to clean before and after usage, purchase from vendors (3-6 months waiting time), and regrind. Glass offers an easily accessible, inexpensive material ($0.04 per knife) with very high compressive strength (3) that can be employed in microtomy of metals (4) as well as biological materials. When the orthogonal machining process is being studied, glass offers additional advantages. Sections of metal or plastic can be dried down on the rake face, coated with Au-Pd, and examined directly in the SEM with no additional handling (5). Figure 1 shows aluminum chips microtomed with a 75° glass knife at a cutting speed of 1 mm/sec with a depth of cut of 1000 Å lying on the rake face of the knife.

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