Assessment of the Formant Frequencies in Normal and Laryngectomized Individuals Using Linear Predictive Coding

Effect of total laryngectomy on vowel production: An acoustic study of vowels produced by alaryngeal speakers of Cantonese

Purpose: To investigate the effect of total laryngectomy on vowel production, the present study examined the change in vowel articulation associated with different types of alaryngeal speech in comparison with laryngeal speech using novel derived formant metrics.Method: Six metrics derived from the first two formants (F1 and F2) including the First and Second Formant Range Ratios (F1RR and F2RR), triangular and pentagonal Vowel Space Area (tVSA and pVSA), Formant Centralisation Ratio (FCR) and Average Vowel Spacing (AVS) were measured from vowels (/i, y, ɛ, a, ɔ, œ, u/) produced by oesophageal (ES), tracheoesophageal (TE), electrolaryngeal (EL), pneumatic artificial laryngeal (PA) speakers, as well as laryngeal speakers.Result: Data revealed a general reduction in articulatory range and a tendency of vowel centralisation in Cantonese alaryngeal speakers. Significant articulatory difference was found for PA and EL compared with ES, TE, and laryngeal speakers.Conclusion: The discrepant results among alaryngeal speakers may be related to the difference in new sound source (external vs internal). Sensitivity and correlation analyses confirmed the use of the matrix of derived formant metrics provided a more comprehensive profile of the articulatory pattern in the alaryngeal population.

Reconstruction of normal sounding speech for laryngectomy patients through a modified CELP codec

Whispered speech can be useful for quiet and private communication, and is the primary means of unaided spoken communication for many people experiencing voice-box deficiencies. Patients who have undergone partial or full laryngectomy are typically unable to speak anything more than hoarse whispers, without the aid of prostheses or specialized speaking techniques. Each of the current prostheses and rehabilitative methods for post-laryngectomized patients (primarily oesophageal speech, tracheo-esophageal puncture, and electrolarynx) have particular disadvantages, prompting new work on nonsurgical, noninvasive alternative solutions. One such solution, described in this paper, combines whisper signal analysis with direct formant insertion and speech modification located outside the vocal tract. This approach allows laryngectomy patients to regain their ability to speak with a more natural voice than alternative methods, by whispering into an external prosthesis, which then, recreates and outputs natural-sounding speech. It relies on the observation that while the pitch-generation mechanism of laryngectomy patients is damaged or unusable, the remaining components of the speech production apparatus may be largely unaffected. This paper presents analysis and reconstruction methods designed for the prosthesis, and demonstrates their ability to obtain natural-sounding speech from the whisper-speech signal using an external analysis-by-synthesis processing framework.

Caracteristicas vocais acústicas de homens com voz e laringe normal

TEMA: características vocais acústicas do filtro e das medidas da fonte vocal masculina. OBJETIVO: realizar uma revisão de literatura descrevendo e discutindo os aspectos que envolvem as características vocais acústicas de homens com laringe normal relacionadas às medidas da fonte e ao filtro vocal. CONCLUSÃO: as medidas de Jita, ShdB e NHR tendem a ser maiores nos homens, enquanto a f0, PHR/HNR e o ATRI tendem a ser menores. As espectrografias tendem a apresentar formantes graves, com média de alcance menor, com escurecimento variável e menos regular do que nas mulheres.

Objective estimation of tracheoesophageal speech ratings using an auditory model

Total laryngectomy is often the treatment of choice for many individuals diagnosed with advanced laryngeal cancer. This procedure alters the normal voice production mechanism, and tracheoesophageal (TE) speech is one alternative method of voicing postlaryngectomy. TE speech is created when pulmonary air is passed through the upper esophagus to create a vibratory source that is then articulated into speech. TE speech is often characterized by abnormal voice quality. Acoustic analysis of TE speech has the potential of quantifying the voice quality and assisting the speech language pathologist in facilitating rehabilitation. Motivated in part by the recent advances in telecommunication industry for speech quality estimation, this paper investigated the application of an auditory model in predicting the ratings of TE speech by normal hearing listeners. The Moore-Glasberg auditory model was employed to extract perceptually relevant features from the acoustic waveform, and these features were later combined to estimate the subjective ratings of TE speech. This approach was validated with a database of subjective ratings of speech samples recorded from 35 TE speakers. Results showed moderate correlations between the objective metrics and the subjective ratings, and these correlations were significantly better than those obtained with traditional methods used in the telecommunication applications.