Modelo incremental recursivo para el análisis de la mecánica del oido medio e interno

El presente trabajo propone la adopción de un modelo de línea de transmisión para la dinámica del oído interno con posible extensión al oído medio basado en una ecuación diferencial que explica la propagación de la energía a lo largo de la estructura modelizada. Se desarrolla un método numérico de integración de la citada ecuación que pone de relieve el papel jugado en la propagación por las funciones características de la línea de transmisión asociada. Se exploran posibles campos de aplicación del modelo en el diseño de ayudas a la audición en sujetos con fuertes deficiencias auditivas por estimulación intracoclea

Evaluating the forensic importance of glottal source features through the voice analysis of twins and non-twin siblings

In this study we have analyzed 853 tokens of the vowel filler [ei], extracted from spontaneous speech fragments of 54 male Spanish speakers (NorthCentral Peninsular variety), each one recorded on two separate sessions. The speakers — to be compared in a pairwise fashion - were divided in four groups: 24 monozygotic (MZ) twins, 10 dizygotic (DZ) twins, 8 non-twin brothers and 12 unrelated speakers. From the extracted vowel fillers, considered long enough for a glottal analysis (around 160 milliseconds), a vector of 68 glottal parameters was created. Our hypothesis that higher similarity values would be found in the intra-pair comparison ofMZ twins than in DZ twins, brothers or unrelated speakers was confirmed, which suggests that the glottal parameters under investigation are genetically influenced. This finding seems of great forensic importance, as a phonetic parameter is considered forensically robust provided that it exhibits large between-speaker variation while it remains as consistent as possible for each speaker (i.e. small within-speaker variation)

Exploring pause fillers in conversational speech for forensic phonetics: findings in a Spanish cohort including twins

Pause fillers occur naturally during conversational speech, and have recently generated interest in their use for forensic applications. We extracted pause fillers from conversational speech from 54 speakers, including twins, whose voices are often perceptually similar. Overall 872 tokens of the sound [e:] were extracted (7-33 tokens per speaker), and objectively characterised using 315 acoustic measures. We used a Random Forest (RF) classifier and tested its performance using a leaveone- sample-out scheme to obtain probabilistic estimates of binary class membership denoting whether a query token belongs to a speaker. We report results using the Receiver Operating Characteristic (ROC) curve, and computing the Area Under the Curve (AUC). When the RF was presented with at least 20 tokens in the training phase for each of the two classes, we observed AUC in the range 0.71-0.98. These findings have important implications in the potential of pause fillers as an additional objective tool in forensic speaker verification

Evaluation of the neo-glottal closure based on the source description in esophageal voice

The characteristics of esophageal voice render its study by traditional acoustic means to be limited and complicate. These limitations are even stronger when working with patients lacking minimal skills to control the required technique. Nevertheless the speech therapist needs to know the performance and mechanics developed by the patient in producing esophageal voice, as the specific techniques required in this case are not as universal and well-known as the ones for normal voicing. Each patient develops different strategies for producing esophageal voice due to the anatomical changes affecting the crico-pharyngeal sphincter (CPS) and the functional losses resulting from surgery. Therefore it is of fundamental relevance that practitioners could count on new instruments to evaluate esophageal voice quality, which on its turn could help in the enhancement of the CPS dynamics. The present work carries out a description of the voice of four patients after undergoing laryngectomy on data obtained from the study of the neo-glottal wave profile. Results obtained after analyzing the open-close phases and the tension of the muscular body on the CPS are shown

Glottal Source Cepstrum Coefficients Applied to NIST SRE 2010

Through the present paper, a novel feature set for speaker recognition based on glottal estimate information is presented. An iterative algorithm is used to derive the vocal tract and glottal source estimations from speech signal. In order to test the importance of glottal source information in speaker characterization, the novel feature set has been tested in the 2010 NIST Speaker Recognition Evaluation (NIST SRE10). The proposed system uses glottal estimate parameter templates and classical cepstral information to build a model for each speaker involved in the recognition process. ALIZE [1] open-source software has been used to create the GMM models for both background and target speakers. Compared to using mel-frequency cepstrum coefficients (MFCC), the misclassification rate for the NIST SRE 2010 reduced from 29.43% to 27.15% when glottal source features are use

Use of Mel Frequency Cepstral Coefficients for Automatic Pathology Detection on Sustained Vowel Phonations: Mathematical and Statistical Justification

This paper presents a justification for the use of MFCC parameters in automatic pathology detection on speech. While such an application has produced good results up to now, only partial explanations to this good performance had been given before. The herein exposed explanation consists of an interpretation of the mathematical transformations involved in MFCC calculation and a statistical analysis that confirms the conclusions drawn from the theoretical reasoning