Biomedical subjects

E B Holmberg

Publications and source records attributed to E B Holmberg.

8 recordsLinked to original sources

PubMed2001

Efficacy of a behaviorally based voice therapy protocol for vocal nodules.

The aim of this study was to assess the effects on vocal function of voice therapy for vocal nodules. Perceptual and physiological progressive changes were examined during a strictly structured, behaviorally based voice therapy protocol in which 11 women with vocal nodules participated. Randomized audio recordings from pretherapy and from each of the therapy approaches (vocal hygiene, respiration, direct facilitation, carryover) were used for perceptual evaluations. Six speech-language pathologists rated ten voice quality parameters. Two evaluation procedures were performed and compared. Interlistener reliability was sufficiently high in both tests. Significant effects of therapy were found for decreased overall dysphonia, press, instability, gratings, roughness, vocal fry, and "scrape." Nonsignificant group effects were found for breathiness, aphonic instances, and lack of sonority. No significant parameter changes occurred between baseline assessment and the completion of the initial (vocal hygiene) phase of therapy. Significant changes were found following the direct facilitation and respiration phases of therapy. Videostroboscopic evaluations made by two laryngologists showed that in no case were the nodules completely resolved. However, the nodules had decreased in size and edema was reduced after therapy for all clients, but one. Combined results suggest: (1) Alterations in vocal function were reflected in perceptual parameters, and (2) the voice therapy had a positive effect on voice quality, vocal status, and vocal function for the majority of the vocal nodule clients.

Adult↗

PubMed1995

Comparisons among aerodynamic, electroglottographic, and acoustic spectral measures of female voice.

This study examines measures of the glottal airflow waveform, the electroglottographic signal (EGG), amplitude differences between peaks in the acoustic spectrum, and observations of the spectral energy content of the third formant (F3), in terms of how they relate to one another. Twenty females with normal voices served as subjects. Both group and individual data were studied. Measurements were made for the vowel in two speech tasks: strings of the syllable /pae/and sustained phonation of /ae/, which were produced at two levels of vocal effort: comfortable and loud voice. The main results were: 1. Significant differences in parameter values between /pae/and/ae/were related to significant differences in the sound pressure level (SPL). 2. An "adduction quotient," measured from the glottal waveform at a 30% criterion, was sensitive enough to differentiate between waveforms reflecting abrupt versus gradual vocal fold closing movements. 3. DC flow showed weak or nonsignificant relationships with acoustic measures. 4. The spectral content in the third formant (F3) in comfortable loudness typically consisted of a mix of noise and harmonic energy. In loud voice, the F3 spectral content typically consisted of harmonic energy. 5. Significant differences were found in all measures between tokens with F3 harmonic energy and tokens with F3 noise, independent of loudness condition. 6. Strong relationships between flow- and EGG-adduction quotients suggested that these signals can be used to complement each other. 7. The amplitude difference between spectral peaks of the first and third formant (F1-F3) was found to add information about abruptness of airflow decrease (flow declination) that may be lost in the glottal waveform signal due to low-pass filtering. The results are discussed in terms of how an integrated use of these measures can contribute to a better understanding of the normal vocal mechanism and help to improve methods for evaluating vocal function.

Adult↗

PubMed1994

Relationships between intra-speaker variation in aerodynamic measures of voice production and variation in SPL across repeated recordings.

Intra-speaker variation in aerodynamic and acoustic measures of voice production across repeated recordings was studied in relation to cross-recording variation in SPL for three normal female and three normal male speakers. Group data for 15 females and 15 males served as the statistical reference. The speech material consisted of syllable strings in soft, normal, and loud voice. Measures were made of (a) parameters characterizing the inverse filtered oral airflow waveform, (b) the inferred average transglottal air pressure and glottal airflow, and (c) SPL. The results showed that intra-speaker parameter variation across recordings was generally less than 2 standard deviations relative to group mean values. In terms of relation to variation in SPL, the measures could be divided into two main groups: (a) For air pressure, AC flow, and maximum flow declination rate, both intra-speaker variation across recordings and inter-speaker (group) variation was related systematically to variation of SPL. For these measures, it is suggested that variation across recordings was due in part to SPL differences, which can be adjusted for statistically, thus facilitating comparisons between absolute values. (b) For other measures, neither intra-speaker variation across recordings nor inter-speaker group variation was systematically related to SPL. However, some of these latter measures changed with SPL in an orderly fashion across soft, normal, and loud voice for individual speakers. The results are discussed in terms of the clinical use of these measures in studies of voice disorders.

Adult↗

PubMed1994

Group differences in measures of voice production and revised values of maximum airflow declination rate.

In previous reports, aerodynamic and acoustic measures of voice production were presented for groups of normal male and female speakers [Holmberg et al., J. Acoust. Soc. Am. 84, 511-529 (1988); J. Voice 3, 294-305 (1989)] that were used as norms in studies of voice disorders [Hillman et al., J. Speech Hear. Res. 32, 373-392 (1989); J. Voice 4, 52-63 (1990)]. Several of the measures were extracted from glottal airflow waveforms that were derived by inverse filtering a high-time-resolution oral airflow signal. Recently, the methods have been updated and a new study of additional subjects has been conducted. This report presents previous (1988) and current (1993) group mean values of sound pressure level, fundamental frequency, maximum airflow declination rate, ac flow, peak flow, minimum flow, ac-dc ratio, inferred subglottal air pressure, average flow, and glottal resistance. Statistical tests indicate overall group differences and differences for values of several individual parameters between the 1988 and 1993 studies. Some inter-study differences in parameter values may be due to sampling effects and minor methodological differences; however, a comparative test of 1988 and 1993 inverse filtering algorithms shows that some lower 1988 values of maximum flow declination rate were due at least in part to excessive low-pass filtering in the 1988 algorithm. The observed differences should have had a negligible influence on the conclusions of our studies of voice disorders.

Air Pressure↗

PubMed1994

Individual variation in measures of voice.

Measures of inferred subglottal air pressure, glottal airflow waveform characteristics, sound pressure level (SPL) and the acoustic spectral slope were studied for individual speakers with normal voices. Combinations of different levels of subglottal air pressure and varying glottal configurations could result in the same SPL. Relatively high air pressure levels were associated with a steep spectral slope, reflecting a more sinusoidal glottal waveform and a relatively abducted membranous glottis, which would result in damping of F1. Data suggested that the interarytenoid glottal opening could vary without systematically affecting SPL or voice quality. The results indicate that the principles of production-related economy of effort and physiological, acoustic and perceptual constraints may apply to voice production.

Air Pressure↗

PubMed1991

A system for signal processing and data extraction from aerodynamic, acoustic, and electroglottographic signals in the study of voice production.

A software system, implemented in the MITSYN languages, is described for signal processing and data extraction from oral airflow, intra-oral air pressure, vocal fold contact area (EGG) and sound pressure signals. Signal processing algorithms are specified in the form of block diagrams; examples are shown for demultiplexing signals into bandwidth-specific, time-aligned signal stream files and for inverse filtering the oral airflow waveform to obtain an approximation of the glottal airflow waveform. Interactive and algorithmic data extraction is performed with a menu-driven procedure that displays the stages of analysis, graphical indications of the results of algorithmically made decisions, and derived results. The system has proven to be useful for obtaining quantities of detailed data on voice production.

Electrodiagnosis↗

PubMed1989

Objective assessment of vocal hyperfunction: an experimental framework and initial results.

This report describes the experimental design and initial results of an ongoing clinical investigation of voice disorders. Its major focus is the development and use of quantitative measures to provide objective descriptions of conditions referred to as "vocal hyperfunction." The experimental design for this project is based on a descriptive theoretical framework, which holds that there are different types and stages of hyperfunctionally related voice disorders. Data consist of indirect measures derived from noninvasive aerodynamic and acoustic recordings including (a) parameters derived from inverse filtered approximations of the glottal air flow waveform; (b) estimates of transglottal pressure, average glottal air flow, glottal resistance and vocal efficiency; and (c) measures of vocal intensity and fundamental frequency. Initial results (based on comparisons among 15 voice patients and 45 normal speakers) support major assumptions that underlie the theoretical framework, and indicate that the measurement approach being utilized is capable of differentiating hyperfunctional from normal voices and hyperfunctional conditions from one another. Organic manifestations of vocal hyperfunction (nodules, polyps, contact ulcers) are accompanied by abnormally high values for the glottal waveform parameters of AC flow and maximum flow declination rate, suggesting increased potential for vocal fold trauma due to high vocal fold closure velocities and collision forces. In contrast, nonorganic manifestations of hyperfunction (functional disorders) tend to be associated with abnormally high levels of unmodulated DC flow, without high values for AC flow and maximum flow declination rate, suggesting reduced potential for vocal fold trauma. Measures also suggest different underlying mechanisms for nodules and polyps as compared to contact ulcers. Results are discussed relative to predictions based on the theoretical framework for vocal hyperfunction.

Adult↗

PubMed1988

Glottal airflow and transglottal air pressure measurements for male and female speakers in soft, normal, and loud voice.

Measurements on the inverse filtered airflow waveform (the "glottal waveform") and of estimated average transglottal pressure and glottal airflow were made from noninvasive recordings of productions of syllable sequences in soft, normal, and loud voice for 25 male and 20 female speakers. Statistical analyses showed that with change from normal to loud voice, both males and females produced loud voice with increased pressure, accompanied by increased ac flow and increased maximum airflow declination rate. With change from normal voice, soft voice was produced with decreased pressure, ac flow and maximum airflow declination rate, and increased dc and average flow. Within the loudness conditions, there was no significant male-female difference in air pressure. Several glottal waveform parameters separated males and females in normal and loud voice. The data indicate higher ac flow and higher maximum airflow declination rate for males. In soft voice, the male and female glottal waveforms were more alike, and there was no significant difference in maximum airflow declination rate. The dc flow did not differ significantly between males and females. Possible relevance to biomechanical differences and differences in voice source characteristics between males and females and across loudness conditions is discussed.

Biomechanical Phenomena↗