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1.
J Acoust Soc Am ; 149(6): 4437, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34241468

RESUMEN

The glossectomy procedure, involving surgical resection of cancerous lingual tissue, has long been observed to affect speech production. This study aims to quantitatively index and compare complexity of vocal tract shaping due to lingual movement in individuals who have undergone glossectomy and typical speakers using real-time magnetic resonance imaging data and Principal Component Analysis. The data reveal that (i) the type of glossectomy undergone largely predicts the patterns in vocal tract shaping observed, (ii) gross forward and backward motion of the tongue body accounts for more change in vocal tract shaping than do subtler movements of the tongue (e.g., tongue tip constrictions) in patient data, and (iii) fewer vocal tract shaping components are required to account for the patients' speech data than typical speech data, suggesting that the patient data at hand exhibit less complex vocal tract shaping in the midsagittal plane than do the data from the typical speakers observed.


Asunto(s)
Glosectomía , Neoplasias de la Lengua , Humanos , Análisis de Componente Principal , Habla , Lengua/diagnóstico por imagen , Lengua/cirugía , Neoplasias de la Lengua/diagnóstico por imagen , Neoplasias de la Lengua/cirugía
2.
J Couns Psychol ; 67(4): 438-448, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32614225

RESUMEN

Artificial intelligence generally and machine learning specifically have become deeply woven into the lives and technologies of modern life. Machine learning is dramatically changing scientific research and industry and may also hold promise for addressing limitations encountered in mental health care and psychotherapy. The current paper introduces machine learning and natural language processing as related methodologies that may prove valuable for automating the assessment of meaningful aspects of treatment. Prediction of therapeutic alliance from session recordings is used as a case in point. Recordings from 1,235 sessions of 386 clients seen by 40 therapists at a university counseling center were processed using automatic speech recognition software. Machine learning algorithms learned associations between client ratings of therapeutic alliance exclusively from session linguistic content. Using a portion of the data to train the model, machine learning algorithms modestly predicted alliance ratings from session content in an independent test set (Spearman's ρ = .15, p < .001). These results highlight the potential to harness natural language processing and machine learning to predict a key psychotherapy process variable that is relatively distal from linguistic content. Six practical suggestions for conducting psychotherapy research using machine learning are presented along with several directions for future research. Questions of dissemination and implementation may be particularly important to explore as machine learning improves in its ability to automate assessment of psychotherapy process and outcome. (PsycInfo Database Record (c) 2020 APA, all rights reserved).


Asunto(s)
Investigación Biomédica/métodos , Aprendizaje Automático , Trastornos Mentales/terapia , Procesamiento de Lenguaje Natural , Psicoterapia/métodos , Alianza Terapéutica , Adolescente , Adulto , Investigación Biomédica/tendencias , Consejo/métodos , Consejo/tendencias , Femenino , Humanos , Aprendizaje Automático/tendencias , Masculino , Trastornos Mentales/psicología , Relaciones Profesional-Paciente , Procesos Psicoterapéuticos , Psicoterapia/tendencias , Universidades/tendencias , Adulto Joven
3.
Magn Reson Med ; 81(1): 234-246, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30058147

RESUMEN

PURPOSE: To improve the depiction and tracking of vocal tract articulators in spiral real-time MRI (RT-MRI) of speech production by estimating and correcting for dynamic changes in off-resonance. METHODS: The proposed method computes a dynamic field map from the phase of single-TE dynamic images after a coil phase compensation where complex coil sensitivity maps are estimated from the single-TE dynamic scan itself. This method is tested using simulations and in vivo data. The depiction of air-tissue boundaries is evaluated quantitatively using a sharpness metric and visual inspection. RESULTS: Simulations demonstrate that the proposed method provides robust off-resonance correction for spiral readout durations up to 5 ms at 1.5T. In -vivo experiments during human speech production demonstrate that image sharpness is improved in a majority of data sets at air-tissue boundaries including the upper lip, hard palate, soft palate, and tongue boundaries, whereas the lower lip shows little improvement in the edge sharpness after correction. CONCLUSION: Dynamic off-resonance correction is feasible from single-TE spiral RT-MRI data, and provides a practical performance improvement in articulator sharpness when applied to speech production imaging.


Asunto(s)
Imagen por Resonancia Magnética , Boca/diagnóstico por imagen , Paladar Blando/fisiología , Faringe/fisiología , Procesamiento de Señales Asistido por Computador , Habla/fisiología , Algoritmos , Simulación por Computador , Voluntarios Sanos , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Reproducibilidad de los Resultados , Lengua/fisiología
4.
J Child Psychol Psychiatry ; 57(8): 927-37, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27090613

RESUMEN

BACKGROUND: Machine learning (ML) provides novel opportunities for human behavior research and clinical translation, yet its application can have noted pitfalls (Bone et al., 2015). In this work, we fastidiously utilize ML to derive autism spectrum disorder (ASD) instrument algorithms in an attempt to improve upon widely used ASD screening and diagnostic tools. METHODS: The data consisted of Autism Diagnostic Interview-Revised (ADI-R) and Social Responsiveness Scale (SRS) scores for 1,264 verbal individuals with ASD and 462 verbal individuals with non-ASD developmental or psychiatric disorders, split at age 10. Algorithms were created via a robust ML classifier, support vector machine, while targeting best-estimate clinical diagnosis of ASD versus non-ASD. Parameter settings were tuned in multiple levels of cross-validation. RESULTS: The created algorithms were more effective (higher performing) than the current algorithms, were tunable (sensitivity and specificity can be differentially weighted), and were more efficient (achieving near-peak performance with five or fewer codes). Results from ML-based fusion of ADI-R and SRS are reported. We present a screener algorithm for below (above) age 10 that reached 89.2% (86.7%) sensitivity and 59.0% (53.4%) specificity with only five behavioral codes. CONCLUSIONS: ML is useful for creating robust, customizable instrument algorithms. In a unique dataset comprised of controls with other difficulties, our findings highlight the limitations of current caregiver-report instruments and indicate possible avenues for improving ASD screening and diagnostic tools.


Asunto(s)
Algoritmos , Trastorno del Espectro Autista/diagnóstico , Escalas de Valoración Psiquiátrica , Máquina de Vectores de Soporte , Adolescente , Adulto , Niño , Preescolar , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
5.
Curr Psychiatry Rep ; 18(5): 49, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27017830

RESUMEN

Empathy is an important psychological process that facilitates human communication and interaction. Enhancement of empathy has profound significance in a range of applications. In this paper, we review emerging directions of research on computational analysis of empathy expression and perception as well as empathic interactions, including their simulation. We summarize the work on empathic expression analysis by the targeted signal modalities (e.g., text, audio, and facial expressions). We categorize empathy simulation studies into theory-based emotion space modeling or application-driven user and context modeling. We summarize challenges in computational study of empathy including conceptual framing and understanding of empathy, data availability, appropriate use and validation of machine learning techniques, and behavior signal processing. Finally, we propose a unified view of empathy computation and offer a series of open problems for future research.


Asunto(s)
Empatía/fisiología , Modelos Teóricos , Humanos
6.
J Couns Psychol ; 63(3): 343-350, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26784286

RESUMEN

The dissemination and evaluation of evidence-based behavioral treatments for substance abuse problems rely on the evaluation of counselor interventions. In Motivational Interviewing (MI), a treatment that directs the therapist to utilize a particular linguistic style, proficiency is assessed via behavioral coding-a time consuming, nontechnological approach. Natural language processing techniques have the potential to scale up the evaluation of behavioral treatments such as MI. We present a novel computational approach to assessing components of MI, focusing on 1 specific counselor behavior-reflections, which are believed to be a critical MI ingredient. Using 57 sessions from 3 MI clinical trials, we automatically detected counselor reflections in a maximum entropy Markov modeling framework using the raw linguistic data derived from session transcripts. We achieved 93% recall, 90% specificity, and 73% precision. Results provide insight into the linguistic information used by coders to make ratings and demonstrate the feasibility of new computational approaches to scaling up the evaluation of behavioral treatments.


Asunto(s)
Consejo/métodos , Entrevista Motivacional/métodos , Procesamiento de Lenguaje Natural , Estudiantes/psicología , Terapia Conductista/métodos , Humanos , Cadenas de Markov
7.
J Acoust Soc Am ; 137(3): 1411-29, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25786953

RESUMEN

This study explores one aspect of the articulatory mechanism that underlies emotional speech production, namely, the behavior of linguistically critical and non-critical articulators in the encoding of emotional information. The hypothesis is that the possible larger kinematic variability in the behavior of non-critical articulators enables revealing underlying emotional expression goal more explicitly than that of the critical articulators; the critical articulators are strictly controlled in service of achieving linguistic goals and exhibit smaller kinematic variability. This hypothesis is examined by kinematic analysis of the movements of critical and non-critical speech articulators gathered using eletromagnetic articulography during spoken expressions of five categorical emotions. Analysis results at the level of consonant-vowel-consonant segments reveal that critical articulators for the consonants show more (less) peripheral articulations during production of the consonant-vowel-consonant syllables for high (low) arousal emotions, while non-critical articulators show less sensitive emotional variation of articulatory position to the linguistic gestures. Analysis results at the individual phonetic targets show that overall, between- and within-emotion variability in articulatory positions is larger for non-critical cases than for critical cases. Finally, the results of simulation experiments suggest that the postural variation of non-critical articulators depending on emotion is significantly associated with the controls of critical articulators.

8.
IEEE Trans Multimedia ; 17(7): 1107-1119, 2015 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-26557047

RESUMEN

This paper presents a computational study of head motion in human interaction, notably of its role in conveying interlocutors' behavioral characteristics. Head motion is physically complex and carries rich information; current modeling approaches based on visual signals, however, are still limited in their ability to adequately capture these important properties. Guided by the methodology of kinesics, we propose a data driven approach to identify typical head motion patterns. The approach follows the steps of first segmenting motion events, then parametrically representing the motion by linear predictive features, and finally generalizing the motion types using Gaussian mixture models. The proposed approach is experimentally validated using video recordings of communication sessions from real couples involved in a couples therapy study. In particular we use the head motion model to classify binarized expert judgments of the interactants' specific behavioral characteristics where entrainment in head motion is hypothesized to play a role: Acceptance, Blame, Positive, and Negative behavior. We achieve accuracies in the range of 60% to 70% for the various experimental settings and conditions. In addition, we describe a measure of motion similarity between the interaction partners based on the proposed model. We show that the relative change of head motion similarity during the interaction significantly correlates with the expert judgments of the interactants' behavioral characteristics. These findings demonstrate the effectiveness of the proposed head motion model, and underscore the promise of analyzing human behavioral characteristics through signal processing methods.

9.
J Acoust Soc Am ; 135(2): EL115-21, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25234914

RESUMEN

This paper describes a spatio-temporal registration approach for speech articulation data obtained from electromagnetic articulography (EMA) and real-time Magnetic Resonance Imaging (rtMRI). This is motivated by the potential for combining the complementary advantages of both types of data. The registration method is validated on EMA and rtMRI datasets obtained at different times, but using the same stimuli. The aligned corpus offers the advantages of high temporal resolution (from EMA) and a complete mid-sagittal view (from rtMRI). The co-registration also yields optimum placement of EMA sensors as articulatory landmarks on the magnetic resonance images, thus providing richer spatio-temporal information about articulatory dynamics.


Asunto(s)
Acústica , Fenómenos Electromagnéticos , Imagen por Resonancia Magnética , Boca/fisiología , Faringe/fisiología , Medición de la Producción del Habla , Habla , Puntos Anatómicos de Referencia , Fenómenos Biomecánicos , Bases de Datos Factuales , Femenino , Humanos , Boca/anatomía & histología , Faringe/anatomía & histología , Reproducibilidad de los Resultados , Factores de Tiempo
10.
Artículo en Inglés | MEDLINE | ID: mdl-39052383

RESUMEN

OBJECTIVE: Affective flexibility, the capacity to respond to life's varying environmental changes in a dynamic and adaptive manner, is considered a central aspect of psychological health in many psychotherapeutic approaches. The present study examined whether affective two-dimensional (i.e., arousal and valence) temporal variability extracted from voice and facial expressions would be associated with positive changes over the course of psychotherapy, at the session, client, and treatment levels. METHOD: A total of 22,741 mean vocal arousal and facial expression valence observations were extracted from 137 therapy sessions in a sample of 30 clients treated for major depressive disorder by nine therapists. Before and after each session, the clients self-reported their level of well-being on the outcome rating scale. Session-level affective temporal variability was assessed as the mean square of successive differences between consecutive two-dimensional affective measures. RESULTS: Session outcome was positively associated with temporal variability at the session level (i.e., within clients, between sessions) and at the client level (i.e., between clients). Importantly, these associations held when controlling for average session- and client-level valence scores. In addition, the expansion of temporal variability throughout treatment was associated with steeper positive session outcome trajectories over the course of treatment. CONCLUSIONS: The continuous assessment of both vocal and facial affective expressions and the ability to extract measures of affective temporal variability from within-session data may enable therapists to better respond and modulate clients' affective flexibility; however, further research is necessary to determine whether there is a causal link between affective temporal variability and psychotherapy outcomes. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

11.
J Acoust Soc Am ; 134(2): EL258-64, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23927234

RESUMEN

It is well-known that the performance of acoustic-to-articulatory inversion improves by smoothing the articulatory trajectories estimated using Gaussian mixture model (GMM) mapping (denoted by GMM + Smoothing). GMM + Smoothing also provides similar performance with GMM mapping using dynamic features, which integrates smoothing directly in the mapping criterion. Due to the separation between smoothing and mapping, what objective criterion GMM + Smoothing optimizes remains unclear. In this work a new integrated smoothness criterion, the smoothed-GMM (SGMM), is proposed. GMM + Smoothing is shown, both analytically and experimentally, to be identical to the asymptotic solution of SGMM suggesting GMM + Smoothing to be a near optimal solution of SGMM.


Asunto(s)
Acústica , Fenómenos Electromagnéticos , Acústica del Lenguaje , Sistema Estomatognático/fisiología , Calidad de la Voz , Fenómenos Biomecánicos , Femenino , Humanos , Masculino , Modelos Estadísticos , Procesamiento de Señales Asistido por Computador , Factores de Tiempo
12.
J Acoust Soc Am ; 134(2): 1378-94, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23927134

RESUMEN

This paper presents a computational approach to derive interpretable movement primitives from speech articulation data. It puts forth a convolutive Nonnegative Matrix Factorization algorithm with sparseness constraints (cNMFsc) to decompose a given data matrix into a set of spatiotemporal basis sequences and an activation matrix. The algorithm optimizes a cost function that trades off the mismatch between the proposed model and the input data against the number of primitives that are active at any given instant. The method is applied to both measured articulatory data obtained through electromagnetic articulography as well as synthetic data generated using an articulatory synthesizer. The paper then describes how to evaluate the algorithm performance quantitatively and further performs a qualitative assessment of the algorithm's ability to recover compositional structure from data. This is done using pseudo ground-truth primitives generated by the articulatory synthesizer based on an Articulatory Phonology frame-work [Browman and Goldstein (1995). "Dynamics and articulatory phonology," in Mind as motion: Explorations in the dynamics of cognition, edited by R. F. Port and T.van Gelder (MIT Press, Cambridge, MA), pp. 175-194]. The results suggest that the proposed algorithm extracts movement primitives from human speech production data that are linguistically interpretable. Such a framework might aid the understanding of longstanding issues in speech production such as motor control and coarticulation.


Asunto(s)
Laringe/fisiología , Modelos Teóricos , Boca/fisiología , Acústica del Lenguaje , Calidad de la Voz , Algoritmos , Fenómenos Biomecánicos , Simulación por Computador , Fenómenos Electromagnéticos , Femenino , Humanos , Masculino , Destreza Motora , Análisis Numérico Asistido por Computador , Reproducibilidad de los Resultados , Medición de la Producción del Habla , Factores de Tiempo
13.
J Acoust Soc Am ; 134(1): 510-9, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23862826

RESUMEN

This paper presents an automatic procedure to analyze articulatory setting in speech production using real-time magnetic resonance imaging of the moving human vocal tract. The procedure extracts frames corresponding to inter-speech pauses, speech-ready intervals and absolute rest intervals from magnetic resonance imaging sequences of read and spontaneous speech elicited from five healthy speakers of American English and uses automatically extracted image features to quantify vocal tract posture during these intervals. Statistical analyses show significant differences between vocal tract postures adopted during inter-speech pauses and those at absolute rest before speech; the latter also exhibits a greater variability in the adopted postures. In addition, the articulatory settings adopted during inter-speech pauses in read and spontaneous speech are distinct. The results suggest that adopted vocal tract postures differ on average during rest positions, ready positions and inter-speech pauses, and might, in that order, involve an increasing degree of active control by the cognitive speech planning mechanism.


Asunto(s)
Epiglotis/fisiología , Glotis/fisiología , Interpretación de Imagen Asistida por Computador/métodos , Labio/fisiología , Imagen por Resonancia Magnética/métodos , Paladar Blando/fisiología , Faringe/fisiología , Fonación/fisiología , Fonética , Habla/fisiología , Lengua/fisiología , Algoritmos , Femenino , Humanos , Contracción Muscular/fisiología , Ventilación Pulmonar/fisiología , Posición Supina/fisiología
14.
JMIR Ment Health ; 10: e45572, 2023 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-37463010

RESUMEN

BACKGROUND: Smartphones and wearable biosensors can continuously and passively measure aspects of behavior and physiology while also collecting data that require user input. These devices can potentially be used to monitor symptom burden; estimate diagnosis and risk for relapse; predict treatment response; and deliver digital interventions in patients with obsessive-compulsive disorder (OCD), a prevalent and disabling psychiatric condition that often follows a chronic and fluctuating course and may uniquely benefit from these technologies. OBJECTIVE: Given the speed at which mobile and wearable technologies are being developed and implemented in clinical settings, a continual reappraisal of this field is needed. In this scoping review, we map the literature on the use of wearable devices and smartphone-based devices or apps in the assessment, monitoring, or treatment of OCD. METHODS: In July 2022 and April 2023, we conducted an initial search and an updated search, respectively, of multiple databases, including PubMed, Embase, APA PsycINFO, and Web of Science, with no restriction on publication period, using the following search strategy: ("OCD" OR "obsessive" OR "obsessive-compulsive") AND ("smartphone" OR "phone" OR "wearable" OR "sensing" OR "biofeedback" OR "neurofeedback" OR "neuro feedback" OR "digital" OR "phenotyping" OR "mobile" OR "heart rate variability" OR "actigraphy" OR "actimetry" OR "biosignals" OR "biomarker" OR "signals" OR "mobile health"). RESULTS: We analyzed 2748 articles, reviewed the full text of 77 articles, and extracted data from the 25 articles included in this review. We divided our review into the following three parts: studies without digital or mobile intervention and with passive data collection, studies without digital or mobile intervention and with active or mixed data collection, and studies with a digital or mobile intervention. CONCLUSIONS: Use of mobile and wearable technologies for OCD has developed primarily in the past 15 years, with an increasing pace of related publications. Passive measures from actigraphy generally match subjective reports. Ecological momentary assessment is well tolerated for the naturalistic assessment of symptoms, may capture novel OCD symptoms, and may also document lower symptom burden than retrospective recall. Digital or mobile treatments are diverse; however, they generally provide some improvement in OCD symptom burden. Finally, ongoing work is needed for a safe and trusted uptake of technology by patients and providers.

15.
Front Digit Health ; 5: 1195795, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37363272

RESUMEN

Introduction: Intelligent ambulatory tracking can assist in the automatic detection of psychological and emotional states relevant to the mental health changes of professionals with high-stakes job responsibilities, such as healthcare workers. However, well-known differences in the variability of ambulatory data across individuals challenge many existing automated approaches seeking to learn a generalizable means of well-being estimation. This paper proposes a novel metric learning technique that improves the accuracy and generalizability of automated well-being estimation by reducing inter-individual variability while preserving the variability pertaining to the behavioral construct. Methods: The metric learning technique implemented in this paper entails learning a transformed multimodal feature space from pairwise similarity information between (dis)similar samples per participant via a Siamese neural network. Improved accuracy via personalization is further achieved by considering the trait characteristics of each individual as additional input to the metric learning models, as well as individual trait base cluster criteria to group participants followed by training a metric learning model for each group. Results: The outcomes of the proposed models demonstrate significant improvement over the other inter-individual variability reduction and deep neural baseline methods for stress, anxiety, positive affect, and negative affect. Discussion: This study lays the foundation for accurate estimation of psychological and emotional states in realistic and ambulatory environments leading to early diagnosis of mental health changes and enabling just-in-time adaptive interventions.

16.
Implement Res Pract ; 4: 26334895231187906, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37790171

RESUMEN

Background: Evidence-based parenting programs effectively prevent the onset and escalation of child and adolescent behavioral health problems. When programs have been taken to scale, declines in the quality of implementation diminish intervention effects. Gold-standard methods of implementation monitoring are cost-prohibitive and impractical in resource-scarce delivery systems. Technological developments using computational linguistics and machine learning offer an opportunity to assess fidelity in a low burden, timely, and comprehensive manner. Methods: In this study, we test two natural language processing (NLP) methods [i.e., Term Frequency-Inverse Document Frequency (TF-IDF) and Bidirectional Encoder Representations from Transformers (BERT)] to assess the delivery of the Family Check-Up 4 Health (FCU4Health) program in a type 2 hybrid effectiveness-implementation trial conducted in primary care settings that serve primarily Latino families. We trained and evaluated models using 116 English and 81 Spanish-language transcripts from the 113 families who initiated FCU4Health services. We evaluated the concurrent validity of the TF-IDF and BERT models using observer ratings of program sessions using the COACH measure of competent adherence. Following the Implementation Cascade model, we assessed predictive validity using multiple indicators of parent engagement, which have been demonstrated to predict improvements in parenting and child outcomes. Results: Both TF-IDF and BERT ratings were significantly associated with observer ratings and engagement outcomes. Using mean squared error, results demonstrated improvement over baseline for observer ratings from a range of 0.83-1.02 to 0.62-0.76, resulting in an average improvement of 24%. Similarly, results demonstrated improvement over baseline for parent engagement indicators from a range of 0.81-27.3 to 0.62-19.50, resulting in an approximate average improvement of 18%. Conclusions: These results demonstrate the potential for NLP methods to assess implementation in evidence-based parenting programs delivered at scale. Future directions are presented. Trial registration: NCT03013309 ClinicalTrials.gov.


Research has shown that evidence-based parenting programs effectively prevent the onset and escalation of child and adolescent behavioral health problems. However, if they are not implemented with fidelity, there is a potential that they will not produce the same effects. Gold-standard methods of implementation monitoring include observations of program sessions. This is expensive and difficult to implement in delivery settings with limited resources. Using data from a trial of the Family Check-Up 4 Health program in primary care settings that served Latino families, we investigated the potential to make use of a form of machine learning called natural language processing (NLP) to monitor program delivery. NLP-based ratings were significantly associated with independent observer ratings of fidelity and participant engagement outcomes. These results demonstrate the potential for NLP methods to monitor implementation in evidence-based parenting programs delivered at scale.

17.
J Magn Reson Imaging ; 35(4): 943-8, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22127935

RESUMEN

PURPOSE: To develop a real-time imaging technique that allows for simultaneous visualization of vocal tract shaping in multiple scan planes, and provides dynamic visualization of complex articulatory features. MATERIALS AND METHODS: Simultaneous imaging of multiple slices was implemented using a custom real-time imaging platform. Midsagittal, coronal, and axial scan planes of the human upper airway were prescribed and imaged in real-time using a fast spiral gradient-echo pulse sequence. Two native speakers of English produced voiceless and voiced fricatives /f/-/v/, /θ/-/ð/, /s/-/z/, /∫/- in symmetrical maximally contrastive vocalic contexts /a_a/, /i_i/, and /u_u/. Vocal tract videos were synchronized with noise-cancelled audio recordings, facilitating the selection of frames associated with production of English fricatives. RESULTS: Coronal slices intersecting the postalveolar region of the vocal tract revealed tongue grooving to be most pronounced during fricative production in back vowel contexts, and more pronounced for sibilants /s/-/z/ than for /∫/-. The axial slice best revealed differences in dorsal and pharyngeal articulation; voiced fricatives were observed to be produced with a larger cross-sectional area in the pharyngeal airway. Partial saturation of spins provided accurate location of imaging planes with respect to each other. CONCLUSION: Real-time MRI of multiple intersecting slices can provide valuable spatial and temporal information about vocal tract shaping, including details not observable from a single slice.


Asunto(s)
Imagen por Resonancia Cinemagnética/métodos , Imagen por Resonancia Magnética/métodos , Medición de la Producción del Habla/métodos , Lengua/fisiología , Pliegues Vocales/fisiología , Voz/fisiología , Adulto , Sistemas de Computación , Femenino , Humanos , Masculino , Lengua/anatomía & histología , Pliegues Vocales/anatomía & histología , Adulto Joven
18.
Magn Reson Med ; 65(5): 1365-71, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21500262

RESUMEN

In speech production research using real-time magnetic resonance imaging (MRI), the analysis of articulatory dynamics is performed retrospectively. A flexible selection of temporal resolution is highly desirable because of natural variations in speech rate and variations in the speed of different articulators. The purpose of the study is to demonstrate a first application of golden-ratio spiral temporal view order to real-time speech MRI and investigate its performance by comparison with conventional bit-reversed temporal view order. Golden-ratio view order proved to be more effective at capturing the dynamics of rapid tongue tip motion. A method for automated blockwise selection of temporal resolution is presented that enables the synthesis of a single video from multiple temporal resolution videos and potentially facilitates subsequent vocal tract shape analysis.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Habla/fisiología , Lengua/fisiología , Artefactos , Simulación por Computador , Análisis de Fourier , Humanos , Procesamiento de Imagen Asistido por Computador , Maxilares/fisiología , Labio/fisiología , Estudios Retrospectivos , Programas Informáticos , Factores de Tiempo
19.
Magn Reson Med ; 65(6): 1711-7, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21590804

RESUMEN

Upper airway MRI can provide a noninvasive assessment of speech and swallowing disorders and sleep apnea. Recent work has demonstrated the value of high-resolution three-dimensional imaging and dynamic two-dimensional imaging and the importance of further improvements in spatio-temporal resolution. The purpose of the study was to describe a novel 16-channel 3 Tesla receive coil that is highly sensitive to the human upper airway and investigate the performance of accelerated upper airway MRI with the coil. In three-dimensional imaging of the upper airway during static posture, 6-fold acceleration is demonstrated using parallel imaging, potentially leading to capturing a whole three-dimensional vocal tract with 1.25 mm isotropic resolution within 9 sec of sustained sound production. Midsagittal spiral parallel imaging of vocal tract dynamics during natural speech production is demonstrated with 2 × 2 mm(2) in-plane spatial and 84 ms temporal resolution.


Asunto(s)
Imagen por Resonancia Magnética/instrumentación , Sistema Respiratorio/anatomía & histología , Adulto , Algoritmos , Trastornos de Deglución/diagnóstico , Diseño de Equipo , Femenino , Humanos , Interpretación de Imagen Asistida por Computador , Imagenología Tridimensional/instrumentación , Masculino , Sensibilidad y Especificidad , Síndromes de la Apnea del Sueño/diagnóstico , Trastornos del Habla/diagnóstico
20.
J Acoust Soc Am ; 129(6): 4014-22, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21682422

RESUMEN

Understanding how the human speech production system is related to the human auditory system has been a perennial subject of inquiry. To investigate the production-perception link, in this paper, a computational analysis has been performed using the articulatory movement data obtained during speech production with concurrently recorded acoustic speech signals from multiple subjects in three different languages: English, Cantonese, and Georgian. The form of articulatory gestures during speech production varies across languages, and this variation is considered to be reflected in the articulatory position and kinematics. The auditory processing of the acoustic speech signal is modeled by a parametric representation of the cochlear filterbank which allows for realizing various candidate filterbank structures by changing the parameter value. Using mathematical communication theory, it is found that the uncertainty about the articulatory gestures in each language is maximally reduced when the acoustic speech signal is represented using the output of a filterbank similar to the empirically established cochlear filterbank in the human auditory system. Possible interpretations of this finding are discussed.


Asunto(s)
Vías Auditivas/fisiología , Cara/fisiología , Gestos , Lenguaje , Modelos Teóricos , Procesamiento de Señales Asistido por Computador , Percepción del Habla , Medición de la Producción del Habla , Estimulación Acústica , Fenómenos Biomecánicos , Simulación por Computador , Cara/diagnóstico por imagen , Femenino , Humanos , Masculino , Radiografía , Espectrografía del Sonido , Factores de Tiempo
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