Voice Perceptions and Quality of Life of Transgender People

Despite the plethora of research documenting that the voice and quality of life (QoL) are related, the exact nature of this relationship is vague. Studies have not addressed people who consider their voice to influence their life and identity, but would not be considered to have a voice “disorder” (e.g., transgender individuals). Individuals seeking vocal feminization may or may not have vocal pathology and often have concerns not addressed on the standard psychosocial measures of voice impact. Recent development of a voice-related QoL measure specific to the needs of transgender care (Transgender Self-Evaluation Questionnaire [TSEQ]) affords opportunity to explore relationships between self-perceived QoL and perceptions of femininity and likability associated with transgender voice. Twenty male-to-female transgender individuals living as a female 100% of the time completed the TSEQ and contributed a speech sample describing Norman Rockwell’s “The Waiting Room” picture. Twenty-five undergraduate listeners rated voice femininity and voice likability after audio-only presentation of each speech sample. Speakers also self-rated their voices on these parameters. For male-to-female transgender clients, QoL is moderately correlated with how others perceive their voice. QoL ratings correlate more strongly with speaker’s self-rated perception of voice compared with others’ perceptions, more so for likability than femininity. This study complements previous research reports that subjective measures from clients and listeners may be valuable for evaluating the effectiveness of treatment in terms of how treatment influences voice-related QoL issues for transgender people.     

Aerodynamic Analysis of Male-to-Female Transgender Voice

The attainment of a feminine-sounding voice is a highly desirable goal among male-to-female transgender (MFT) persons, but this goal may be difficult for many to accomplish. The characteristics associated with a feminine vocal quality include increases in fundamental frequency and in vocal breathiness. In this study, we used inverse-filtering of the airflow signal to indirectly assess vocal fold function in 13 MFT persons. Each participant was asked to sustain the vowel /a/ first in her biological male voice and then again in her female voice. In addition, these vowel productions were compared with vowels produced by age-matched biologic women and men. The results of the study revealed a significant increase in maximum flow declination rate during female voice production. Perceptual ratings of a feminine voice were associated with a fundamental frequency (F0) of 180 Hz or greater, although F0 did not differ significantly between male and female voice production. These results are discussed relative to the mechanisms that obtained a feminine-sounding voice.     

Changes in Children''s Voices: The Effect of Cognitive Cues

Variation in duration and frequency during two readings of each of four sentences by 15 normal 9- and 10-year-old children were compared. Instructions to the children included overt cues designed specifically to elicit durational and frequency changes. Children demonstrated increased sentence variability in their voices when they were cued. Specific key words in the four sentences were also analyzed and results indicated that semantic content in addition to parameter-specific cognitive cues provided a significant effect. The male 9 and 10-year-old subjects showed less variability in “no cue” readings than the females, but showed a greater increase in voice change during the “cognitive cue” readings. Implications for theory and practice are discussed.     

Dissimilarity and the Classification of Male Singing Voices

Traditionally, timbre has been defined as that perceptual attribute that differentiates two sounds when pitch and loudness are equal, and thus is a measure of dissimilarity. By such a definition, each voice possesses a set of timbres, and the ability to identify any voice or voice category across different pitch-loudness-vowel combinations must be due to an ability to "link" these timbres by abstracting the "timbre transformation," the manner in which timbre subtly changes across pitch and loudness for a specific voice or voice category. Using stimuli produced across the singing range by singers from different voice categories, this study sought to examine how timbre and pitch interact in the perception of dissimilarity in male singing voices. This study also investigated whether or not listener experience affects the perception of timbre as a function of pitch. The resulting multidimensional scaling (MDS) representations showed that for all stimuli and listeners, dimension 1 correlated with pitch, while dimension 2 correlated with spectral centroid and separated vocal stimuli into the categories baritone and tenor. Dimension 3 appeared highly idiosyncratic depending on the nature of the stimuli and on the experience of the listener. Inexperienced listeners appeared to rely more heavily on pitch in making dissimilarity judgments than did experienced listeners. The resulting MDS representations of dissimilarity across pitch provide a glimpse of the timbre transformation of voice categories across pitch.     

Acoustic Analysis of Pathological Voices Compressedwith MPEG System

The MPEG-1 Layer 3 compression schema of audio signal, commonly known as mp3, has caused a great impact in recent years as it has reached high compression rates while conserving a high sound quality. Music and speech samples compressed at high bitrates are perceptually indistinguishable from the original samples, but very little was known about how compression acoustically affects the voice signal. A previous work with normal voices showed a high fidelity at high-bitrate compressions both in voice parameters and the amplitude-frequency spectrum. In the present work, dysphonic voices were tested through two studies. In the first study, spectrograms, long-term average spectra (LTAS), and fast Fourier transform (FFT) spectra of compressed and original samples of running speech were compared. In the second study, intensities, formant frequencies, formant bandwidths, and a multidimensional set of voice parameters were tested in a set of sustained phonations. Results showed that compression at high bitrates (96 and 128 kbps) preserved the relevant acoustic properties of the pathological voices. With compressions at lower bitrates, fidelity decreases, introducing some important alterations. Results from both works, Gonzalez and Cervera and this paper, open up the possibility of using MPEG-compression at high bitrates to store or transmit high-quality speech recordings, without altering their acoustic properties.     

Voice Care Knowledge Among Clinicians and People With Healthy Voices or Dysphonia

An important clinical component in the prevention and treatment of voice disorders is voice care and hygiene. Research in voice care knowledge has mainly focussed on specific groups of professional voice users with limited reporting on the tool and evidence base used. In this study, a questionnaire to measure voice care knowledge was developed based on "best evidence." The questionnaire was validated by measuring specialist voice clinicians' agreement. Preliminary data are then presented using the voice care knowledge questionnaire with 17 subjects with nonorganic dysphonia and 17 with healthy voices. There was high (89%) agreement among the clinicians. There was a highly significant difference between the dysphonic and the healthy group scores (P = 0.00005). Furthermore, the dysphonic subjects (63% agreement) presented with less voice care knowledge than the subjects with healthy voices (72% agreement). The questionnaire provides a useful and valid tool to investigate voice care knowledge. The findings have implications for clinical intervention, voice therapy, and health prevention.     

Acoustic Changes in Student Actors' Voices After 12 Months of Training

This study was to evaluate acoustic changes in student actors' voices after 12 months of actor training. The design used was a longitudinal study. Eighteen students enrolled in an Australian tertiary 3-year acting program (nine male and nine female) were assessed at the beginning of their acting course and again 12 months later using a questionnaire, interview, maximum phonation time (MPT), reading, spontaneous speaking, sustained phonation tasks, and a pitch range task. Samples were analyzed for MPT, fundamental frequency across tasks, pitch range for speaking and reading, singing pitch range, noise-to-harmonic ratio, shimmer, and jitter. After training, measures of shimmer significantly increased for both male and female participants. Female participants' pitch range significantly increased after training, with a significantly lower mean frequency for their lowest pitch. The finding of limited or negative changes for some measures indicate that further investigation is required into the long-term effects of actor voice training and which parameters of voicing are most targeted and valued in training. Particular investigation into the relationship between training targets and outcomes could more reliably inform acting programs about changes in teaching methodologies. Further research into the relationship between specific training techniques, physiological changes, and vocal changes may also provide information on implementing more evidence-based training methods.     

Dissimilarity and the Classification of Female Singing Voices: A Preliminary Study

Traditionally, timbre has been defined as that perceptual attribute that differentiates two sounds when pitch and loudness are equal and thus is a measure of dissimilarity. By such a definition, each voice possesses a set of timbres, and the identity of any voice or voice category across different pitch-loudness-vowel combinations must be due to an abstraction of the pattern of timbre transformation. Using stimuli produced across the singing range by singers from different voice categories, this study sought to examine how timbre and pitch interact in the perception of dissimilarity. This study also investigated whether listener experience affects the perception of timbre as a function of pitch. The resulting multidimensional scaling (MDS) representations showed that for all stimuli and listeners, dimension 1 correlated with pitch, whereas dimension 2 correlated with spectral centroid and separated vocal stimuli into the categories mezzo-soprano and soprano. Dimension 3 appeared highly idiosyncratic depending on the nature of the stimuli and on the experience of the listener. Inexperienced listeners appeared to rely more heavily on pitch in making dissimilarity judgments than did experienced listeners. The resulting MDS representations of dissimilarity across pitch provide a glimpse of the timbre transformation of voice categories across pitch.     

Acoustical Aspects of Vocal Function Following Radiotherapy for Early T1a Laryngeal Cancer

We evaluated acoustic voice characteristics of 18 male patients undergoing radiotherapy. The subjects were seen for voice assessment preradiotherapy and at 1 month, 3 months, 6 months, and 1 year following radiotherapy. A multidimensional voice analysis computer program (IVANS, Avaaz Innovations, 1998) was employed to evaluate measures of traditional frequency and amplitude perturbation as well as time-based and linear prediction (LP) modeled "noise" parameters of the acoustic output in conjunction with perceptual judgments of overall vocal quality. The results indicate vocal deterioration of vocal function immediately following radiotherapy with gradual and significant improvement in acoustic and perceptual features over 9 to 12 months following the radiation treatment. Measures of glottal noise demonstrated higher sensitivity than frequency-based measures of voice perturbation, and with more consistent, less variable changes in acoustical voice output from the preradiation to the 12 month postradiation periods. Future research evaluating vowel type and acoustic perturbation measures with a larger sample of subjects over a longer time period seems warranted.     

Categorizing Normal and Pathological Voices: Automated and Perceptual Categorization

Objectives

The aims of the present study were to evaluate the accuracy of an elaborated automated voice categorization system that classified voice signal samples into healthy and pathological classes and to compare it with classification accuracy that was attained by human experts.

Material and Methods

We investigated the effectiveness of 10 different feature sets in the classification of voice recordings of the sustained phonation of the vowel sound /a/ into the healthy and two pathological voice classes, and proposed a new approach to building a sequential committee of support vector machines (SVMs) for the classification. By applying “genetic search” (a search technique used to find solutions to optimization problems), we determined the optimal values of hyper-parameters of the committee and the feature sets that provided the best performance. Four experienced clinical voice specialists who evaluated the same voice recordings served as experts. The “gold standard” for classification was clinically and histologically proven diagnosis.

Results

A considerable improvement in the classification accuracy was obtained from the committee when compared with the single feature type-based classifiers. In the experimental investigations that were performed using 444 voice recordings coming from 148 subjects, three recordings from each subject, we obtained the correct classification rate (CCR) of over 92% when classifying into the healthy-pathological voice classes, and over 90% when classifying into three classes (healthy voice and two nodular or diffuse lesion voice classes). The CCR obtained from human experts was about 74% and 60%, respectively.

Conclusion

When operating under the same experimental conditions, the automated voice discrimination technique based on sequential committee of SVM was considerably more effective than the human experts.